Rice antioxidants: phenolic acids, flavonoids, anthocyanins, proanthocyanidins, tocopherols, tocotrienols, γ-oryzanol, and phytic acid

Accumulation patterns of anthocyanin and γ-oryzanol during black rice grain development

Pigmented rice, especially black rice, is gaining popularity as it is rich in antioxidants such as anthocyanins and γ-oryzanol. At present, knowledge about temporal control of biosynthesis and accumulation of antioxidants during grain development is limited. To address this, the accumulation patterns of anthocyanins and γ-oryzanol were assessed in two distinct black rice genotypes over the course of grain development, and the expression of known regulatory genes for anthocyanin biosynthesis was examined. The results indicated that total γ-oryzanol content increased continuously throughout grain development, while total anthocyanins peaked at dough stage (15 to 21 days after flowering) followed by a decline until grain maturity in both genotypes. However, the rate of decrease in anthocyanin content differed between genotypes, and a more prominent decline in cyanidin 3-O-glucoside (C3G) relative to peonidin 3-O-glucoside (P3G) was observed for both. Anthocyanin content was closely linked with the expression of key regulatory genes in the MBW (MYB-bHLH-WD40) complex. This improved knowledge of the genotype-specific biosynthesis (anthocyanins only) and accumulation patterns of anthocyanins and γ-oryzanol can inform subsequent research efforts to increase concentrations of these key antioxidants in black rice grains.

Sustainable valorisation of bioactive molecules from rice husks through hydrothermal extraction for chitosan-based bioplastic production

Rice husks are a low value byproduct, even though it possesses molecules with great potential, such as arabinoxylans, proteins, and silica. These molecules can be used to improve mechanical and physicochemical properties of materials for food packaging. In this work, hydrothermal treatment was used for a sustainable extraction of the valuable molecules present in rice husks. Various extraction temperatures (180, 200, and 220 °C) were performed targeting to extract fractions with distinct compositions. The water extract obtained at 220 °C demonstrated the highest extraction yield, 3 times superior to conventional hot water extraction. These extracts exhibited high content of proteins, phenolic compounds, and carbohydrates, particularly arabinoxylans. This extract was incorporated in chitosan-based films in different ratios, 1:0.1, 1:0.3, and 1:0.5 (chitosan:extract, w:v). The film with the lowest extract ratio presented the highest flexibility (higher elongation and lower Young's modulus) when compared to the pristine chitosan film. The antioxidant capacity was also increased, achieving an antioxidant capacity of >10-fold in comparison to control film. The results revealed that hydrothermal extraction emerges as an environmentally friendly and sustainable methodology for extracting valuable compounds from rice industry byproducts. This method exhibits significant potential to impart flexible and antioxidant properties to biobased materials.

Antioxidant Activity, Glycemic Response, and Functional Properties of Rice Cooked with Red Palm Oil

High rice consumption levels accompanied by a lifestyle lacking in physical activity leads to obesity and diabetes due to the rice consumed generally has high digestibility and high glycemic index. Red palm oil (RPO) is a vegetable oil suggested to have the potential to reduce starch digestibility and increase the bioactive compounds of rice. This research aimed to find out the best cooking method to produce rice with a sensory quality similar to regular rice and to study the effect of the best cooking method on the glycemic response and physicochemical properties of rice. The results showed that RPO addition increased the antioxidant activities and total carotenoid levels of rice. The addition of RPO after cooking has better antioxidant activity and total carotenoid than before cooking. Adding 2% RPO before or after cooking produced rice with similar or better sensory quality than regular rice. Rice cooked with 2% RPO added before cooking had a lower glycemic response than regular rice, which was suggested to be caused by the increasing formation of the amylose lipid complex and the triglycerides that protected the starch from amylase enzyme. The formation of the amylose lipid complex and triglyceride layers protecting rice starch was confirmed by the new peaks of the FTIR spectra, the appearance of oil-coated starch morphology, and the changes in the proportion of C and O atoms. In conclusion, the addition of 2% RPO before the cooking process can be considered as a cooking method to produce rice for diabetic patients.

Development of Germinated-Brown-Rice-Based Novel Functional Beverage Enriched with γ-Aminobutyric Acid: Nutritional and Bio-Functional Characterization

γ-aminobutyric acid (GABA), recognized as a primary inhibitory neurotransmitter within the brain, serves a crucial role in the aging process and in neurodegenerative conditions such as Alzheimer's disease. Research has demonstrated the beneficial effects of GABA, particularly for elderly individuals. Given that elderly individuals often encounter challenges with swallowing food, beverages designed to address dysphagia represent a preferable option for this demographic. Among the different processing techniques, the germination process triggers biochemical changes, leading to an increase in certain nutrients and bioactive compounds (e.g., GABA). Therefore, we attempted to develop a novel functional beverage utilizing germinated brown rice enriched with GABA and studied its nutritional and bio-functional characterization. The optimal conditions (X1, X2, X3 and X4.) were determined: powdered sugar (40 g), chocolate powder (20 g), sodium carboxymethyl cellulose (0.5 g), GBR (220 g), and water (440 mL). The results of storage studies indicated that the germinated-brown-rice-based beverage exhibited favorable nutritional attributes, including increased γ-oryzanol (52.73 ± 1.56%), total phenolic content (26.68 ± 1.56 mg GAE/100 g), niacin (5.17 ± 0.14%), and GABA (42.12 ± 0.63 mg/100 g) levels. Additionally, the beverage demonstrated notable antioxidant activity (74.23 ± 2.37 µmol TE/100 g), suggesting potential health-promoting effects. Sensory evaluation revealed satisfactory acceptability among consumers, highlighting its palatability. Overall, this study elucidates the development of a novel functional beverage utilizing germinated brown rice enriched with GABA, offering promising nutritional and bio-functional characteristics for health-conscious consumers.

Identification of biochemical indices for brown spot (Bipolaris oryzae) disease resistance in rice mutants and hybrids

Brown spot caused by Bipolaris oryzae is a major damaging fungal disease of rice which can decrease the yield and value of produce due to grain discoloration. The objectives of the current study were to investigate and understand the biochemical indices of brown spot disease resistance in rice. A total of 108 genotypes (mutant and hybrid) along with Super Basmati and parent RICF-160 were evaluated against brown spot disease. The genotypes exhibiting resistant and susceptible responses to brown spot disease according to the IRRI standard disease rating scale were screened and selected. To study the biochemical response mechanism, forty five selected genotypes along with Super Basmati and RICF-160 were analyzed using the biochemical markers. The physiological and biochemical analysis provided valuable insights and confirmed the resistance of rice hybrids and mutants against brown spot disease. Positive correlations were observed among stress bio-markers and disease response. Rice genotypes i.e. Mu-AS-8, Mu-AS-19, Mu-AS-20 and Mu-AS-35 exhibited moderate resistant response while Hy-AS-92, Hy-AS-98, Hy-AS-99, Hy-AS-101, Hy-AS-102 and Hy-AS-107 showed resistant response to brown spot disease. Brown spot resistant rice genotypes had lesser values of malondialdehyde and total oxidant status and higher antioxidant activities i.e. superoxide dismutase, peroxidase, total phenolic content and lycopene. The selected resistant rice genotypes had resistance capacity against Bipolaris oryzae stress. In conclusion, identified resistant mutants i.e. Mu-AS-8, Mu-AS-19, Mu-AS-20 and Mu-AS-35 and hybrids i.e. Hy-AS-92, Hy-AS-98, Hy-AS-99, Hy-AS-101, Hy-AS-102 and Hy-AS-107 could be used in rice breeding program to achieve sustainable rice production by coping the emerging challenge of brown spot disease under variable climate conditions.

Dietary rice bran attenuates hepatic stellate cell activation and liver fibrosis in mice through enhancing antioxidant ability

Various endogenous and exogenous stimuli can result in an inflammatory response and collagen deposition in the liver, which affect liver function and increase the risk of developing liver cirrhosis and cancer. Rice bran, the main by-product of rice milling, contains various nutrients which possess hepatoprotective activities. In this study, we investigated the effects of rice bran on carbon tetrachloride (CCl4)-induced liver fibrosis in mice. Mice were fed a rice-bran-containing diet (10% rice bran w/w) or a standard diet with or without an injection of 20% CCl4 to induce liver fibrosis. Our results showed that feeding a rice-bran-containing diet could alleviate CCl4-induced liver damage, collagen deposition, and expressions of fibrosis-related genes, including α-smooth muscle actin (α-SMA), collagen 1a2 (COL1A2), and transforming growth factor-β (TGF-β) in liver tissues. Moreover, consumption of rice bran enhanced phase II detoxification and antioxidant gene expressions, including Gsta3, Gstp1, Catalase, SOD1, SOD2, and SOD3. Treatment with γ-oryzanol, the major bioactive compound in rice bran, decreased the sensitivity of hepatic stellate cells (HSCs) to TGF-β1-induced α-SMA, COL1A2, and phosphorylated smad2 expressions. In conclusion, a rice-bran-containing diet may have beneficial effects on liver fibrogenesis through increased antioxidant and detoxification activities. γ-Oryzanol, the major bioactive compound of rice bran, can inhibit activation of HSCs.

Impact of soaking and cooking treatments on the physicochemical and antioxidant properties of parboiled and non-parboiled rice (Oryza sativa L.)

The effects of soaking and cooking on the physicochemical properties and bioactive compounds of two parboiled and non-parboiled rice cultivars (BRRI-28 and Katari bhog) were investigated in this study. Total phenolic content (TPC) increased significantly (p ≤ 0.5) after soaking, while total flavonoid content (TFC) and proanthocyanidin content (PC) decreased significantly (p ≤ 0.5) compared to untreated rice samples. TPC increased by around 23% and 20% in parboiled BRRI 28 and Katari bhog rice extracts, respectively, due to the cooking process, while TFC and PC decreased significantly. DPPH radical scavenging increased whereas reducing power activity decreased after soaking and cooking in parboiled BRRI 28. After processing, the protein, starch, and amylose content of all samples decreased in the majority of cases. After being soaked, all samples L * and b * values increased as compared to raw rice samples. As a result, it can be concluded that the treatment of soaking and cooking of parboiled rice (BRRI-28) was suitable to improve the antioxidant properties as compared to non-parboiled rice.

Evaluation of rheological, textural, and sensory characteristics of optimized vegan rice puddings prepared by various plant-based milks

Nowadays, plant-based milks are being considered as an alternative to dairy milk due to their advantages, such as sustainability, reduced allergenicity, health benefits, and lactose-free nature. Plant-based milks are widely used in the preparation of desserts, cheese-like products, and beverages, among other applications. The aim of the present study was to formulate vegan rice puddings using various commercially available plant-based milks as a sustainable alternative to dairy milk. For this aim, central composition design was applied to optimize the key processing parameters of the Thermomix®, including temperature (80-90°C), time (6-14 min), and the amount of rice flour (6-10%, w/v), using response surface methodology (RSM). According to the RSM results, the optimum conditions were found to be 90°C for 12.5 min with 6.5% rice flour, as they exhibited minimal phase separation and similar rheological and textural properties to dairy rice pudding. Soya milk pudding had the highest hardness value among the other plant-based milk puddings, and whole fat milk, soya, oat, coconut, and cow's milks showed the best gel unity, according to the cohesiveness results. Phase separation, an important parameter for storage stability, was not observed during 7-day storage at 4°C in all groups, except for pistachio milk rice pudding. Rheological results demonstrated that all vegan pudding samples exhibited a gel-like structure with storage modulus (G') exceeding loss modulus (G″) values. According to the descriptive sensory evaluation, coconut, oat, and soya milk rice puddings received the highest scores in overall acceptability. Our findings suggest that industrial plant-based rice puddings have great potential as a novel product that meets the dietary needs of the vegan community by offering acceptable flavor and texture.

Germination-induced changes in anthocyanins and proanthocyanidins: A pathway to boost bioactive compounds in red rice

This study aimed to investigate the specific changes in the anthocyanins and proanthocyanidins content of red rice during germination. Different methods including chemical detection, UPLC-QToF/MS, and metabolite analysis were used to examine these changes. The findings showed a significant increase in the overall levels of polyphenols and pigments in red rice as the germination period advanced. Specifically, the proanthocyanidins being the predominant pigments showed a significant increase during later stages of germination. Whereas, the anthocyanin levels reached their peak after 12 h of germination and subsequently declined. Furthermore, six anthocyanins and three proanthocyanidins were identified among the pigment constituents. Additionally, several significant precursor substances associated with pigments were identified, and their contents showed a significant increase, indicating that the proanthocyanidin synthesis pathway is activated by germination. These dynamic changes suggest that germination effectively stimulated the synthesis and accumulation of both anthocyanins and proanthocyanidins, thereby improving the nutritional value of red rice.

Effects of Parboiling on Chemical Properties, Phenolic Content and Antioxidant Capacity in Colored Landrace Rice

Parboiling influences chemical compositions in rice grains. The objectives of this study were to evaluate the change in chemical content, total phenolic content and antioxidant capacity of landrace rice genotypes under parboiling conditions and to identify the genotypes suitable for production of parboiled rice. Landrace rice varieties used in this study consisted of Glam Feang, Glam Tonkeaw, Kawgum, Glam Luem Phua, Medmakham, Deang Sakonnakhon, Sang Yod, Kawniewd-eang, Mali Deang, KDML105 and RD6. Parboiling reduced fiber content, total phenolic content and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical-scavenging activity in rice grains. Fiber contents were 1.46% in brown rice (unpolished rice) and 1.40% in parboiled rice (24 h of soaking and 48 h of incubation). Total phenolic contents were 205.67 mg/100 g seed in brown rice and 35.34 mg/100 g seed in parboiled rice. Antioxidant capacity (DPPH) reduced from 68.45% in brown rice to 26.23% in parboiled rice. Ash content and protein content were not significantly affected by the parboiling process. Medmakham cv. had the highest total phenolic content and antioxidant capacity in brown rice and parboiled rice. Gum Leamphea cv. and Medmakham cv. were the best genotypes for ash content, protein content, total phenolic content and antioxidant capacity (DPPH) in brown rice and parboiled rice. Glam Feang cv. had the highest protein contents in brown rice and parboiled rice although it had low total phenolic content and antioxidant capacity. Cluster analysis further showed variation among genotypes, revealing distinct groupings in brown rice and parboiled rice based on chemical properties, phenolic content and antioxidant capacity. This research significantly contributes to a better understanding on how parboiling affects rice compositions and nutritional values. It emphasizes the importance of nuanced comprehension of how different rice varieties respond to parboiling, aiding informed decisions in rice processing and selection to meet specific nutritional needs.

Abscisic Acid Affects Phenolic Acid Content to Increase Tolerance to UV-B Stress in Rhododendron chrysanthum Pall

The presence of the ozone hole increases the amount of UV radiation reaching a plant's surface, and UV-B radiation is an abiotic stress capable of affecting plant growth. Rhododendron chrysanthum Pall. (R. chrysanthum) grows in alpine regions, where strong UV-B radiation is present, and has been able to adapt to strong UV-B radiation over a long period of evolution. We investigated the response of R. chrysanthum leaves to UV-B radiation using widely targeted metabolomics and transcriptomics. Although phytohormones have been studied for many years in plant growth and development and adaptation to environmental stresses, this paper is innovative in terms of the species studied and the methods used. Using unique species and the latest research methods, this paper was able to add information to this topic for the species R. chrysanthum. We treated R. chrysanthum grown in a simulated alpine environment, with group M receiving no UV-B radiation and groups N and Q (externally applied abscisic acid treatment) receiving UV-B radiation for 2 days (8 h per day). The results of the MN group showed significant changes in phenolic acid accumulation and differential expression of genes related to phenolic acid synthesis in leaves of R. chrysanthum after UV-B radiation. We combined transcriptomics and metabolomics data to map the metabolic regulatory network of phenolic acids under UV-B stress in order to investigate the response of such secondary metabolites to stress. L-phenylalanine, L-tyrosine and phenylpyruvic acid contents in R. chrysanthum were significantly increased after UV-B radiation. Simultaneously, the levels of 3-hydroxyphenylacetic acid, 2-phenylethanol, anthranilate, 2-hydroxycinnamic acid, 3-hydroxycinnamic acid, α-hydroxycinnamic acid and 2-hydroxy-3-phenylpropanoic acid in this pathway were elevated in response to UV-B stress. In contrast, the study in the NQ group found that externally applied abscisic acid (ABA) in R. chrysanthum had greater tolerance to UV-B radiation, and phenolic acid accumulation under the influence of ABA also showed greater differences. The contents of 2-phenylethanol, 1-o-p-coumaroyl-β-d-glucose, 2-hydroxy-3-phenylpropanoic acid, 3-(4-hydroxyphenyl)-propionic acid and 3-o-feruloylquinic ac-id-o-glucoside were significantly elevated in R. chrysanthum after external application of ABA to protect against UV-B stress. Taken together, these studies of the three groups indicated that ABA can influence phenolic acid production to promote the response of R. chrysanthum to UV-B stress, which provided a theoretical reference for the study of its complex molecular regulatory mechanism.

OsGSTU34, a Bz2-like anthocyanin-related glutathione transferase transporter, is essential for rice (Oryza sativa L.) organs coloration

Anthocyanins are a flavonoid compound known as one of the most important chromogenic substances. They play several functions, including health promotion and sustaining plants during adverse conditions. They are synthesized at the endoplasmic reticulum and sequestered in the vacuole. In this work, we generated knock-out lines of OsGSTU34, a glutathione transporter's tau gene family, with no transgene line and off-target through CRISPR/Cas9 mutagenesis and highlighted the loss of pigmentation in rice flowers, leaves, stems, shoots, and caryopsis. The anthocyanin quantification in the wild-type BLWT and mutant line BLG34-8 caryopsis showed that cyanidin-3-O-glucoside (C3G) and peonidin-3-O-glucoside (P3G) were almost undetectable in the mutant line. A tandem mass tag (TMT) labeling proteomic analysis was conducted to elucidate the proteomic changes in the BLWT and BLG34-8. The result revealed that 1175 proteins were altered, including 408 that were down-regulated and 767 that were upregulated. The accumulation of the OsGSTU34-related protein (Q8L576), along with several anthocyanin-related proteins, was down-regulated. The enrichment analysis showed that the down-regulated proteins were enriched in different pathways, among which the phenylpropanoid biosynthesis pathway, flavonoid biosynthesis metabolites, and anthocyanin biosynthesis pathway. Protein interaction network prediction revealed that glutathione-S-transferase (Q8L576) was connected to the proteins involved in the flavonoid and anthocyanin biosynthesis pathways, such as flavanone 3-dioxygenase 1 (Q7XM21), leucoanthocyanidin dioxygenase 1 (Q93VC3), 4-coumarate-CoA ligase 2 (Q42982), phenylalanine ammonia-lyase (P14717), chalcone synthase 1 (Q2R3A1), and 4-coumarate-CoA ligase 5 (Q6ZAC1). However, the expression of the most important anthocyanin biosynthesis gene was not altered, suggesting that only the transport mechanism was affected. Our findings highlight new insight into the anthocyanin pigmentation in black rice and provide new perspectives for future research.

Anthocyanins-natural pigment of colored rice bran: Composition and biological activities

Rice by-products are a potential source of various bioactive substances with great processing potential, which are receiving increasing attention. Among them, rice bran is a by-product of rice milling, with high nutritional value and health benefits. Colored rice bran contains a large amount of anthocyanins responsible for color and bioactivities. And anthocyanins are often added to foods as a natural pigment, serving to enhance both the visual appeal and nutritional value. Recent advances in the composition and bioactivities of four common colored rice bran anthocyanins (black, purple, red, and purple red rice) are reviewed in this paper. Rice bran anthocyanins have been confirmed to exhibit biological potential for human health, with their main biological activities being antioxidant, anti-atherosclerosis, anti-cancer, neuroprotective, retinoprotective, immunomodulatory, anti-aging and anti-obesity effects. The structure of anthocyanins determines their biological activities. The anthocyanins composition of rice bran with different colors varied greatly, while that of rice bran with the same color is also slightly different, which is attributed to the rice varieties, growing environment and cropping conditions. However, it remains necessary to conduct further clinical studies to support the health activities of anthocyanins. The present review provides information value for the further development and comprehensive utilization of rice bran anthocyanins.

Potential roles of cereal bioactive compounds in the prevention and treatment of type 2 diabetes: A review of the current knowledge

Diabetes is one of the most common non-communicable diseases in both developed and underdeveloped countries with a 9.3% prevalence. Unhealthy diets and sedentary lifestyles are among the most common reasons for type 2 diabetes mellitus (T2DM). Diet plays a crucial role in both the etiology and treatment of T2DM. There are several recommendations regarding the carbohydrate intake of patients with T2DM. One of them is about reducing the total carbohydrate intake and/or changing the type of carbohydrate to reduce the glycaemic index. Cereals are good sources of carbohydrates in the diet with a significant amount of soluble and non-soluble fiber content. Apart from fiber, it has been shown that the bioactive compounds present in cereals such as proteins, phenolic compounds, carotenoids, and tocols have beneficial impacts in the prevention and treatment of T2DM. Moreover, cereal by-products especially the by-products of milling processes, which are bran and germ, have been reported to have anti-diabetic activities mainly because of their fiber and polyphenols content. Considering the potential functions of cereals in patients with T2DM, this review focuses on the roles of cereal bioactive compounds in the prevention and treatment of type 2 diabetes.

α-Glucosidase inhibitors from the husks of rice Oryza sativa L

Rice husk is one of the most plentiful agriculture by-products in rice producing areas, which harbors a substantial proportion of biological metabolites, however, it has not been well studied. As an attempt to utilize it as a productive manner, phytochemical investigation on rice husk has performed and led to the isolation of three undescribed (1, 2, and 7), along with twelve known components (3-6, and 8-15). Those chemical structures were elucidated based on massive spectroscopic methods. Among them, compounds 4, 6-8, and 10-13 have been shown to act as α-glucosidase inhibitors. Notably, the most active compounds, 10/11, demonstrated comparable α-glucosidase inhibitory effect (IC50 = 1.83 ± 0.11 μg/mL) to that of 1-deoxynojirimycin (IC50 = 1.02 ± 0.16 μg/mL). For the molecular docking simulation studies, compounds 10/11 showed relative binding interactions with α-glucosidase enzyme (PDB ID: 3A4A) that similar to those reference inhibitors. Additionally, the crude extract of O. sativa demonstrated better α-glucosidase inhibitory effect to that of isolated components, with the IC50 value at 1.25 ± 0.07 μg/mL.

Effect of Pigmented Rice Consumption on Cardiometabolic Risk Factors: A Systematic Review of Randomized Controlled Trials

PURPOSE OF REVIEW

Dietary patterns that include polyphenols may help manage cardiometabolic risk factors. Pigmented rice contains phenolic acids and flavonoids that contribute to its antioxidant properties. This review examined the effect of polyphenol-containing pigmented rice on antioxidant status, lipid profile, glucose/insulin, blood pressure, and weight among adults. Four electronic databases including PubMed, ProQuest, EBSCOhost, and Google Scholar were systematically searched for relevant articles published in English since 2000, using PRISMA guidelines (PROSPERO registration: CRD42022358132). Two-staged screening resulted in the inclusion of seventeen (seven acute, ten chronic) randomized controlled trials. A random effects model was conducted on cardiometabolic outcomes reported in at least three studies.

RECENT FINDINGS

Acute intake increased plasma antioxidant activity and lowered postprandial glucose and insulin levels. Chronic consumption was associated with reductions in fasting glucose (WMD: -1.60 mg/dL; 95% CI:-3.05,-0.14, p = 0.03, k = 5, n = 349), weight (WMD: -0.23 kg, 95% CI: -0.44, -0.02, p = 0.03, k = 3, n = 182), and diastolic blood pressure (WMD: -1.39 mmHg, 95% CI: -2.21, -0.56, p = 0.001, k = 3, n = 185). No effect on total cholesterol, low-density lipoprotein, high-density lipoprotein, triglycerides, body mass index, and systolic blood pressure was found. The consumption of pigmented rice may improve cardiometabolic risk factors. However, the small number of studies and differences in study design, including participants' health status, form of rice utilized, and duration of intervention, support the need for more high-quality trials to further investigate these findings.

Strategies to fortify the nutritional values of polished rice by implanting selective traits from brown rice: A nutrigenomics-based approach

Whole-grain cereals are important components of a healthy diet. It reduces the risk of many deadly diseases like cardiovascular diseases, diabetes, cancer, etc. Brown rice is an example of whole grain food, which is highly nutritious due to the presence of various bioactive compounds (flavonoids, phenolics, vitamins, phytosterols, oils, etc.) associated with the rice bran layer of brown rice. White rice is devoid of the nutritious rice bran layer and thus lacks the bioactive compounds which are the major attractants of brown rice. Therefore, to confer health benefits to the public at large, the nutrigenomic potential of white rice may be improved by integrating the phytochemicals associated with the rice bran layer of brown rice into it via biofortification processes like conventional breeding, agronomic practices, metabolic engineering, CRISPR/Cas9 technology, and RNAi techniques. Thus, this review article focuses on improving the nutritional qualities of white/polished rice through biofortification processes, utilizing new breeding technologies (NBTs).

Health-promoting germinated rice and value-added foods: a comprehensive and systematic review of germination effects on brown rice

Over the last 30 years, thousands of articles have appeared examining the effects of soaking and germinating brown rice (BR). Variable germination conditions and methods have been employed to measure different health-beneficial parameters in a diverse germplasm of BR. Research results may therefore appear inconsistent with occasional anomalies, and it may be difficult to reach consensus concerning expected trends. Herein, we amassed a comprehensive review on germinated brown rice (GBR), attempting to codify 133 peer-reviewed articles regarding the effects on 164 chemical parameters related to health and nutrition in BR and in value-added food products. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA-2020) approach was used to direct the flow of the literature search. A pair-wise comparison t-test was performed to deliver an overall approach indicating when a given compound has been found to significantly increase or decrease through germination, which was grouped into GABA and polyamines, γ-Oryzanol and phytosterols, phenolic compounds, vitamins, proteins and amino acids, starchy carbohydrates, free sugars, lipids, minerals and phytic acid. This resource will stimulate interest in germinating rice and optimistically help increase both production and consumption of highly nutritious, health-beneficial rice with pigmented bran.

Active compounds: A new direction for rice value addition

The development of rice active compounds is conducive to improving the added value of rice. This paper focused on the types and effects of active compounds in rice. Furthermore, it summarized the effect of rice storage and processing technology on rice active compounds. We conclude the following: Rice contains a large number of active compounds that are beneficial to humans. At present, the research on the action mechanism of rice active compounds on the human body is not deep enough, and the ability to deeply process rice is insufficient, greatly limiting the development of the rice active compound industry. To maximize the added value of rice, it is necessary to establish a dedicated preservation and processing technology system based on the physicochemical properties of the required active compounds. Additionally, attention should be paid to the development and application of composite technologies during the development of the rice active compound industry.

Stabilization of Vitamin A by Cereal Bran: The Importance of the Balance between Antioxidants, Pro-oxidants, and Oxidation-Sensitive Components

This study investigated the contribution of bran antioxidants and lipids to the stabilizing effect of cereal bran on vitamin A during accelerated storage. Hereto, wheat and rice bran samples subjected to a sequential extraction process were used. Vitamin A stabilization was more pronounced for wheat compared to rice bran. This was attributed to the higher antioxidant capacity and lower degree of lipid oxidation of wheat compared to rice bran. Removal of the chloroform/methanol-extractable fraction resulted in a substantial decrease in vitamin A retention from 78 to 26% for wheat bran and from 30 to 0% for rice bran after 2 weeks of accelerated storage. However, the vitamin A-stabilizing effect could not be attributed to specific components. The ability of cereal bran to stabilize vitamin A is therefore believed to be determined by the balance of antioxidants, pro-oxidants, and oxidation-sensitive components in the system.

Effect of processing methods and storage on the bioactive compounds of black rice (Oryza sativa L.): a review

Compared to brown and white rice, black rice contains more nutrients and numerous unique bioactive substances, such as essential amino acids, dietary fiber, γ-oryzanols, γ-aminobutyric acid, phenolic compounds, and anthocyanins, which makes it highly valuable for development and use. Whole-grain black rice typically requires a certain amount of processing prior to consumption, with the primary goal of enhancing the taste and texture of whole grains and their products. However, various new processing technologies have been effectively applied to the processing of black rice and the enhancement of its qualitative characteristics, but they also have both positive and negative effects on its nutritional quality. Therefore, evaluation of changes in concentrations of the bioactive substances as natural antioxidants due to processing and storage conditions is critical for establishing dietary guidelines for rice. This review highlights the primary bioactive components of black rice and provides a discussion of the impact of processing methods and storage on the bioactive components of black rice. Furthermore, we summarized the issues that currently exist in the processing and storage of black rice.

Discovery of new functions of food proteins and their structural development for multifunctional applications

Proteins and peptides derived from various food sources are used in a variety of applications, including functional foods, pharmaceuticals, and cosmetics. The three-dimensional structure of proteins provides useful insights into their functions and essential information for the creation of proteins with new functions. In this review, a series of functional conversion technologies based on protein structural information derived from foods traditionally consumed in Japan, such as natto (fermented soybeans) and rice, are introduced. For natto, we first identified 2 types of Bacillus subtilis-derived endolytic and exolytic enzymes with different modes of action on soybean cell wall polysaccharides and then focused on the technology used to create an endolytic enzyme from an exolytic enzyme. By applying this technology, a method for creating novel bioactive peptides from rice seed proteins was established. The modified peptides created could provide diverse options for the production of substances such as pharmaceuticals and cosmetic materials.

Explicating genetic architecture governing nutritional quality in pigmented rice

Rice is one of the most important staple plant foods that provide a major source of calories and nutrients for tackling the global hunger index especially in developing countries. In terms of nutritional profile, pigmented rice grains are favoured for their nutritional and health benefits. The pigmented rice varieties are rich sources of flavonoids, anthocyanin and proanthocyanidin that can be readily incorporated into diets to help address various lifestyle diseases. However, the cultivation of pigmented rice is limited due to low productivity and unfavourable cooking qualities. With the advances in genome sequencing, molecular breeding, gene expression analysis and multi-omics approaches, various attempts have been made to explore the genetic architecture of rice grain pigmentation. In this review, we have compiled the current state of knowledge of the genetic architecture and nutritional value of pigmentation in rice based upon the available experimental evidence. Future research areas that can help to deepen our understanding and help in harnessing the economic and health benefits of pigmented rice are also explored.

Artificial warming affects sugar signals and flavonoid accumulation to improve female willows' growth faster than males

Increasing global warming is severely affecting tree growth and development. However, research on the sex-specific responses of dioecious trees to warming is scarce. Here, male and female Salix paraplesia were selected for artificial warming (an increase of 4 °C relative to ambient temperature) to investigate the effects on morphological, physiological, biochemical and molecular responses. The results showed that warming significantly promoted the growth of female and male S. paraplesia, but females grew faster than males. Warming affected photosynthesis, chloroplast structures, peroxidase activity, proline, flavonoids, nonstructural carbohydrates (NSCs) and phenolic contents in both sexes. Interestingly, warming increased flavonoid accumulation in female roots and male leaves but inhibited it in female leaves and male roots. The transcriptome and proteome results indicated that differentially expressed genes and proteins were significantly enriched in sucrose and starch metabolism and flavonoid biosynthesis pathways. The integrative analysis of transcriptomic, proteomic, biochemical and physiological data revealed that warming changed the expression of SpAMY, SpBGL, SpEGLC and SpAGPase genes, resulting in the reduction of NSCs and starch and the activation of sugar signaling, particularly SpSnRK1s, in female roots and male leaves. These sugar signals subsequently altered the expression of SpHCTs, SpLAR and SpDFR in the flavonoid biosynthetic pathway, ultimately leading to the differential accumulation of flavonoids in female and male S. paraplesia. Therefore, warming causes sexually differential responses of S. paraplesia, with females performing better than males.

γ-Oryzanol ameliorates fine dust-induced premature endothelial senescence and dysfunction via attenuating oxidative stress

Various cardiovascular diseases are associated with endothelial senescence, and a recent study showed that fine dust (FD)-induced premature endothelial senescence and dysfunction is associated with increased oxidative stress. The aim of the present study was to investigate protective effect of rice bran extract (RBE) and its major component of γ-Oryzanol (γ-Ory) against FD-induced premature endothelial senescence. Porcine coronary artery endothelial cells (PCAECs) were treated with FD alone or with RBE or γ-Ory. Senescence-associated β-galactosidase (SA-β-gal) activity, expression of cell cycle regulatory proteins, and oxidative stress levels were evaluated. The results indicated that SA-β-gal activity in the FD-treated PCAECs was attenuated by RBE and γ-Ory. Additionally, γ-Ory inhibited FD-induced cell cycle arrest, restored cell proliferation, and reduced the expression of cell cycle regulatory proteins. γ-Ory also inhibited oxidative stress and prevented senescence-associated NADPH oxidase and LAS activity in FD-exposed ECs suggesting that γ-Ory could protect against FD-induced ECs senescence and dysfunction.

Integrative HPLC profiling and transcriptome analysis revealed insights into anthocyanin accumulation and key genes at three developmental stages of black rice (Oryza sativa. L) caryopsis

Introduction

Anthocyanins are plants' secondary metabolites belonging to the flavonoid class with potential health-promoting properties. They are greatly employed in the food industry as natural alternative food colorants for dairy and ready-to-eat desserts and pH indicators. These tremendous advantages make them economically important with increasing market trends. Black rice is a rich source of anthocyanin that can be used to ensure food and nutritional security around the world. However, research on anthocyanin accumulation and gene expression during rice caryopsis development is lacking.

Methods

In this study, we combined high-performance liquid chromatography (HPLC) and transcriptome analysis to profile the changes in anthocyanin content and gene expression dynamics at three developmental stages (milky, doughy, and mature).

Results

Our results showed that anthocyanin accumulation started to be visible seven days after flowering (DAF), increased rapidly from milky (11 DAF) to dough stage, then started decreasing after the peak was attained at 18 DAF. RNA-seq showed that 519 out of 14889, 477 out of 17914, and 1614 out of 18810 genes were uniquely expressed in the milky, doughy, and mature stages, respectively. We performed three pairwise comparisons: milky vs. dough, milky vs. mature, and dough vs. mature, and identified 6753, 9540, and 2531 DEGs, respectively. The DEGs' abundance was higher in milky vs. mature, with 5527 up-regulated genes and 4013 down-regulated genes, while it was smaller in dough vs. mature, with 1419 up-regulated genes and 1112 down-regulated DEGs. This result was consistent with the changes in anthocyanin profiling, and the expression of structural, regulatory, and transporter genes involved in anthocyanin biosynthesis showed their highest expression at the dough stage. Through the gene expression profile and protein interaction network, we deciphered six main contributors of the anthocyanin peak observed at dough stage, including OsANS, OsDFR, OsGSTU34, OsMYB3, OsbHLH015, and OsWD40-50.

Discussion

This study is the first to report the investigation of anthocyanin and gene expression at three developmental stages of black rice caryopsis. The findings of this study could aid in predicting the best harvesting time to achieve maximum anthocyanin content and the best time to collect samples for various gene expression analysis, laying the groundwork for future research into the molecular mechanisms underlying rice caryopsis coloration.

Food Composition Databases (FCDBs): A Bibliometric Analysis

Food composition databases (FCDBs) are important tools that provide information on the nutritional content of foods. Previously, it was largely unclear what nutritional contents and which FCDBs were involved in highly cited papers. The bibliometric study aimed to identify the most productive authors, institutions, and journals. The chemicals/chemical compounds with high averaged citations and FCDBs used by highly cited papers were identified. In July 2023, the online database Web of Science Core Collection (WoSCC) was queried to identify papers related to FCDBs. A total of 803 papers were identified and analyzed. The first paper indexed in WoSCC was published in 1992 by Pennington, which described the usefulness of FCDB for researchers to identify core foods for their own studies. In that paper, the FCDB described was the USDA 1987-88 NFCS (the United States Department of Agriculture 1987-88 Nationwide Food Consumption Survey). The most productive author was Dr. Paul M. Finglas, the Head of the Food Databanks National Capability at the Quadram Institute (Norwich, UK) and the Managing Director of EuroFIR. His most cited paper among this dataset was about the development of an online Irish food composition database together with EuroFIR. The most productive institutions were the USDA and the World Health Organization (WHO) instead of universities. Flavonoid was the most recurring chemical class among the highly cited ones. The anti-oxidative properties and protective effects against heart disease and cancer of flavonoids might be some of the reasons for their popularity in research. Among the highly cited papers, the most heavily used FCDBs were the USDA database for the flavonoid content of selected foods, Fineli, the USDA National Nutrient Database for Standard Reference (USNDB), EuroFIR eBASIS-Bioactive Substances in Food Information Systems, and Phenol-Explorer. High-quality national and international FCDBs should be promoted and made more accessible to the research and public communities to promote better nutrition and public health on a global scale.

Nutritional Profiles of Yoom Noon Rice from Royal Initiative of Southern Thailand: A Comparison of White Rice, Brown Rice, and Germinated Brown Rice

For long-term food sustainability and security, it is crucial to recognize and preserve Indigenous rice varieties and their diversity. Yoom Noon is one of the non-glutinous rice (Oryza sativa L.) varieties being conserved as part of the Phanang Basin Area Development Project, which is administered by the Royal Initiative of Nakhon Si Thammarat in Southern Thailand. The goal of this research was to compare the nutritional profiles of Yoom Noon white rice, brown rice, and germinated brown rice. The results indicated that carbohydrate content was found to be the most plentiful macronutrient in all processed Yoom Noon rice types, accounting for 67.1 to 81.5% of the total. White rice had the highest carbohydrate content (p < 0.05), followed by brown rice and germinated brown rice. Brown rice had more protein and fat than white rice (p < 0.05). The maximum protein, dietary fiber, and ash content were found in germinated brown rice, followed by brown rice and white rice (p < 0.05). White rice had the highest amylose content, around 24% (p < 0.05), followed by brown rice (22%), and germinated brown rice (20%). Mg levels in all white, brown, and germinated brown rice ranged from 6.59 to 10.59 mg/100 g, which was shown to be the highest among the minerals studied (p < 0.05). Zn (4.10-6.18 mg/100 g) was the second most abundant mineral, followed by Fe (3.45-4.92 mg/100 g), K (2.61-3.81 mg/100 g), Mn (1.20-4.48 mg/100 g), Ca (1.14-1.66 mg/100 g), and Cu (0.16-0.23 mg/100 g). Se was not found in any processed Yoom Noon rice. Overall, brown rice had the highest content of macro- and micronutrients (p < 0.05). In all processed rice, thiamin was found in the highest amount (56-85 mg/100 g), followed by pyridoxine (18-44 g/100 g) and nicotinamide (4-45 g/100 g) (p < 0.05). Riboflavin was not identified in any of the three types of processed Yoom Noon rice. Individual vitamin concentrations varied among processed rice, with germinated brown rice having the highest thiamine content by around 1.5 and 1.3 folds compared to white and brown rice, respectively. The GABA level was the highest in germinated rice (585 mg/kg), which was around three times higher than in brown rice (p < 0.05), whereas GABA was not detectable in white rice. The greatest total extractable flavonoid level was found in brown rice (495 mg rutin equivalent (RE)/100 g), followed by germinated brown rice (232 mg RE/100 g), while white rice had no detectable total extractable flavonoid. Brown rice had the highest phytic acid level (11.2 mg/100 g), which was 1.2 times higher than germinated brown rice (p < 0.05). However, phytic acid was not detected in white rice. White rice (10.25 mg/100 g) and brown rice (10.04 mg/100 g) had the highest non-significant rapidly available glucose (RAG) values, while germinated brown rice had the lowest (5.33 mg/100 g). In contrast, germinated brown rice had the highest slowly available glucose (SAG) value (9.19 mg/100 g), followed by brown rice (3.58 mg/100 g) and white rice (1.61 mg/100 g) (p < 0.05).

Spinel nanocomposite (nMnZnFe2O4) synchronously promotes grain yield and Fe-Zn biofortification in non-aromatic rice

Soils deficient in essential micro-nutrients produce nutritionally starved crops that do not fulfill human nutritional requirements. This is getting serious since progressively increasing nutritional disorders are being diagnosed in residents of third-world countries like Pakistan. During this study, we synthesized a spinel nanocomposite (nMnZnFe2O4) and investigated its effectiveness in improving the micronutrient status and yield traits of rice. The nMnZnFe2O4 exhibited a cubic structure at the most prominent peak (311); a crystallite size of 44 nm, and an average grain size ranging from 7 to 9 μm. Foliar application of this nanocomposite was performed to 45 days old plants at concentrations 0, 10, 20, 30, 40, and 50 mg L-1, and data from rice plant parts (straw, husk, and grain) was recorded at maturity. Agronomic traits like the number of tillers, straw dry weight, root dry biomass, and grain yield per plant were improved by nMnZnFe2O4 application (+34.4% yield). Whereas some biochemical traits like amino acids, soluble sugars, flavonoids, and phenolics varied significantly in rice plant parts compared to the control. Above all, the maximum Zn and Fe concentrations in rice grain were recorded through foliar application of spinel nanocomposite (40 and 50 mg L-1). Therefore, results indicated that micronutrient supply in the form of a nanocomposite could positively regulate nutritional quality and rice grain yield.

Drying kinetics and quality dynamics of ultrasound-assisted dried selenium-enriched germinated black rice

Black rice is a functional food due to its higher protein, fiber, iron, antioxidant compounds, and other health benefits than traditional rice. The ultrasonic (US) pretreatments (10, 20, and 50 min) followed by hot-air drying (50, 60, and 70 °C) were applied to study the drying kinetics, mathematical modeling, thermodynamics, microstructure, bioactive profile, volatile compounds and to lock the nutritional composition of selenium-enriched germinated black rice (SeGBR). Ultrasonic-treated samples exhibited a 20.5% reduced drying time than control ones. The Hii model accurately describes the drying kinetics of SeGBR with the highest R2 (>0.997 to 1.00) among the fifteen studied models. The activation energy values in US-SeGBR varied from 3.97 to 13.90 kJ/mol, while the specific energy consumption ranged from 6.45 to 12.32 kWh/kg, which was lower than untreated. The obtained thermodynamic attributes of dried black rice revealed that the process was endothermic and non-spontaneous. Gallic acid, kaempferol, and cyanidin 3-glucoside were present in high concentrations in phenolics, flavonoids, and anthocyanins, respectively. The HS-SPME-GC-MS investigation detected and quantified 55 volatile compounds. The US-treated SeGBR had more volatile compounds, which may stimulate the release of more flavorful substances. The scanning electronic micrograph shows that the US-treated samples absorbed high water through several micro-cavities. Selenium concentration was significantly higher in US-treated samples at 50 °C than in control samples. In conclusion, ultrasound-assisted hot-air drying accelerated drying and improved SeGBR quality, which is crucial for the food industry and global promotion of this healthiest rice variety.

Mining nutri-dense accessions from rice landraces of Assam, India

The Indian subcontinent is the primary center of origin of rice where huge diversity is found in the Indian rice gene pool, including landraces. North Eastern States of India are home to thousands of rice landraces which are highly diverse and good sources of nutritional traits, but most of them remain nutritionally uncharacterized. Hence, nutritional profiling of 395 Assam landraces was done for total starch, amylose content (AC), total dietary fiber (TDF), total protein content (TPC), oil, phenol, and total phytic acid (TPA) using official AOAC and standard methods, where the mean content for the estimated traits were found to be 75.2 g/100g, 22.2 g/100g, 4.67 g/100g, 9.8 g/100g, 5.26%, 0.40 GAE g/100g, and 0.34 g/100g for respectively. The glycaemic index (GI) was estimated in 24 selected accessions, out of which 17 accessions were found to have low GI (<55). Among different traits, significant correlations were found that can facilitate the direct and indirect selection such as estimated glycemic index (EGI) and amylose content (-0.803). Multivariate analyses, including principal component analysis (PCA) and hierarchical clustering analysis (HCA), revealed the similarities/differences in the nutritional attributes. Four principal components (PC) i.e., PC1, PC2, PC3, and PC4 were identified through principal component analysis (PCA) which, contributed 81.6% of the variance, where maximum loadings were from protein, oil, starch, and phytic acid. Sixteen clusters were identified through hierarchical clustering analysis (HCA) from which the trait-specific and biochemically most distant accessions could be identified for use in cultivar development in breeding programs.

Ethnoveterinary practises of medicinal plants used for the treatment of different cattle diseases: A case study in East Khasi Hill district of Meghalaya, North East India

Introduction

For generations, the inhabitants of Meghalaya have relied on medicinal plants to maintain the health of their livestock and treat various illnesses that may afflict their animals. Due to the lack of survey for use and documentation, these plants have never been undertaken. Therefore, it is imperative to explore the diversity, utilization, and phytochemical profile of these plants and quantitatively analyse the data to identify important medicinal plants. By doing so, we can better understand the potential of these plants for developing novel drugs.

Methods

Frequent field trips were made for the collection of ethnoveterinary data of medicinal plants from local animal-keepers, traditional healers (THs) and inhabitants of different age groups. This information was gathered through semi-structured interviews, individual discussions, direct field-use observation, and questionnaires. A total of 52 informants (35 females and 17 males) were interviewed from seven rural villages and the information obtained from them were quantitatively analysed using the informant consensus factor (ICF), and fidelity level (FL). Additionally, for each documented plant, available published literature was extensively surveyed to identify the presence of bioactive chemical compounds responsible for their therapeutic effects.

Results

During the present study, a total 96 plants, distributed into 87 genera and 43 families were identified and recorded for their use in ethnoveterinary practices against more than 25 diseases. Out of the recorded plant species, the Fabaceae family was found to be the most dominant with seven species, followed by Poaceae and Lamiaceae with six species each, and Moraceae with five species. The leaves (50.00%) and seeds (12.50%) were the most frequently used plant parts, while the paste (30 species) was the common mode of application. Aegle marmelos Correa exhibited a fidelity level (FL) of 100% for indigestion, while Tagetes erecta L. had a fidelity level of 94.11% for wound treatment, making them the most promising candidates for further study. The highest FIC value of 1.00 was recorded for the treatment of neurological disorder (1.00), followed by foot and mouth disease (FIC 0.91), which depicted that some species were frequently utilized to treat multiple livestock ailments.

Conclusion

The study presents trustworthy information about medicinal plants and their associated indigenous ethnoveterinary knowledge. It has been scientifically proven that these plants contain bioactive compounds responsible for their therapeutic properties. However, this knowledge is in danger of being lost due to factors like socioeconomic changes, environmental and technological alterations, and lack of interest from younger generations. Therefore, it is essential to document this empirical folklore knowledge systematically and take measures to protect and conserve it.

Salinity Treatments Promote the Accumulations of Momilactones and Phenolic Compounds in Germinated Brown Rice

This is the first investigation, conducted in a completely randomized design (CRD), to determine the effects of different salinity levels (75 and 150 mM) and germination periods (3, 4, and 5 days) on momilactone and phenolic accumulations in germinated brown rice (GBR) var. Koshihikari. Particularly, the identification of bioactive compounds was confirmed using electrospray ionization-mass spectrometry (ESI-MS) and nuclear magnetic resonance (NMR) spectroscopy (¹H and ¹³C). Momilactone A (MA) and momilactone B (MB) amounts were determined by ultra-performance liquid chromatography-electrospray ionization-mass spectrometry (UPLC-ESI-MS), whereas other compounds were quantified by spectrophotometry and high-performance liquid chromatography (HPLC). Accordingly, GBR under B2 treatment (75 mM salinity for 4 days) showed the greatest total phenolic and flavonoid contents (14.50 mg gallic acid and 11.06 mg rutin equivalents, respectively, per g dry weight). GBR treated with B2 also accumulated the highest quantities of MA, MB, ρ-coumaric, ferulic, cinnamic, salicylic acids, and tricin (18.94, 41.00, 93.77, 139.03, 46.05, 596.26, and 107.63 µg/g DW, respectively), which were consistent with the strongest antiradical activities in DPPH and ABTS assays (IC₅₀ = 1.58 and 1.78 mg/mL, respectively). These findings have implications for promoting the value of GBR consumption and rice-based products that benefit human health.

Comparative analysis of metabolite profiling and free radical scavenging activity in phenotypic variants of OsCOP1 colored rice mutant seed

Interest in colored rice has been increasing due to its health benefits. This study examined the metabolite profiling of CONSTITUTIVELY PHOTOMORPHOGENIC 1 (COP1) mutated rice seed (yel-mutant). The wild-type (WT) and the yel-mutant having yellow (y)- and purple (p)-pericarp variants from Chucheong (cc) and Samkwang (sk) cultivars were investigated for differences in bioactive metabolite profiles and free radical scavenging activity. The total fatty acid content decreased by >50% in the yel-mutant against the WT, while no significant difference was observed between yellow- and purple-pericarp variants (p < 0.05). The yel-mutant of both cultivars showed significantly higher flavone contents than their WT (non-detected). Most of the metabolites examined were highly produced in the yel-cc-p and the yel-sk-y than in the other phenotypic variants studied. This study provides further useful information for colored rice breeding by revealing the detailed biofunctional metabolic profile under COP1 mutation in colored rice.

Effect of Gamma-irradiation on the Physicochemical, Functional, and Antioxidant Properties of Unpigmented Brown Whole Rice Flour

Whole grain brown rice, being a rich source of fiber and other bioactive compounds like polyphenols is effective in reducing the risk of chronic diseases including cardiovascular diseases, hypercholesterolemia and Type II diabetes. The study was aimed to evaluate the effect of gamma irradiation on the physicochemical, functional and antioxidant properties of whole grain brown rice flour. The brown rice flour was conditioned to two different moisture contents of 10% and 12% and treated with gamma irradiation doses of 0 kGy (native or control), 2.5 kGy and 5 kGy. Moisture, protein, fat, ash and carbohydrate content of native flour was found as 10 g/100 g, 6.54 g/100 g, 1.54 g/100 g, 1.0 g/100 g, and 81.48 g/100 g, respectively. The hunter color 'L', 'a', and 'b' values of the native brown rice flour sample were found as 81.95, -0.97 and 17.36, respectively and were non-significantly (p ≥ 0.05) affected by gamma irradiation. Apparent amylose content was observed to decrease significantly (p ≤ 0.05) from 29.97 to 20.30 g/100 g with the increase in gamma irradiation dose and moisture content. The pasting properties such as peak viscosity, trough viscosity and final viscosity of all the flour samples decreased significantly (p ≤ 0.05) with the increase in irradiation dose. The functional properties such as water and oil absorption and emulsion capacities were increased while emulsion stability and foaming stability decreased upon irradiation. Irradiation led to an overall increase in the antioxidant activity of rice flours. In general, FTIR spectra revealed a decrease in the absorption intensities of the functional groups. Therefore, it can be concluded that gamma irradiation can be used as a tool to modify the physicochemical properties of rice flours as well as to improve their antioxidant properties.

Improving γ-Oryzanol and γ-Aminobutyric Acid Contents in Rice Beverage Amazake Produced with Brown, Milled and Germinated Rices

Rice is an important source of γ-oryzanol (GO) and γ-aminobutyric acid (GABA), which are bioactive compounds that may benefit blood lipid and pressure control. Both GO and GABA can be improved by germination and fermentation. Fermentation with A. oryzae produces Koji, a rice-based starter for Amazake, a naturally sweet beverage. Germinated rice (brown and milled rice), were tested to improve those bioactive compounds during the fermentation process. The resulting Koji was optimised to GO and GABA through a response surface methodology; α-amylase activity and starch content were also assessed. The different rice matrix resulting from the germination largely impacted the biosynthesis of GABA, α-amylase and starch contents. Amazake, obtained by germinated rice, has increased GO and GABA contents when compared to the one obtained from milled rice (from a non-detectable value to 27.65 ± 0.23 mg/100 g for GO and from 163.95 ± 24.7 to 271.53 ± 5.7 mg/100 g for GABA). A panel of 136 Portuguese consumers tasted the beverage in a blind overall tasting test followed by an informed test, using 9-point scales. The consumer scores had a mean value of 4.67 ± 1.9 and 4.9 ± 1.8, meaning that cultural differences may play an important role with regard to liking and accepting Amazake.

Composition, Microbiota, Mechanisms, and Anti-Obesity Properties of Rice Bran

Rice is a major cereal crop and a staple food for nearly 50% of people worldwide. Rice bran (RB) is a nutrient-rich by-product of rice processing. RB is rich in carbohydrates, fibers, proteins, lipids, minerals, and several trace elements (phosphorus, calcium, magnesium, potassium, and manganese). The extraction process and storage have influenced RB extracts and RB oil's quality. The RB composition has also varied on the rice cultivars. The color of RB indicates the richness of the bioactive compounds, especially anthocyanins. γ-oryzanol, tocopherols, tocotrienols, and unsaturated fatty acids are major components of RB oil. It has been established that RB supplementation could improve the host's health status. Several preclinical and clinical studies have reported that RB has antioxidant, anticancer, anti-inflammatory, anticolitis, and antidiabetic properties. The beneficial biological properties of RB are partially attributed to its ability to alter the host microbiome and help to maintain and restore eubiosis. Non-communicable diseases (NCDs), including heart disease, diabetes, cancer, and lung disease, account for 74% of deaths worldwide. Obesity is a global health problem and is a major reason for the development of NCDs. The medical procedures for managing obesity are expensive and long-term health supplements are required to maintain a healthy weight. Thus, cost-effective natural adjuvant therapeutic strategy is crucial to treat and manage obesity. Several studies have revealed that RB could be a complementary pharmacological candidate to treat obesity. A comprehensive document with basic information and recent scientific results on the anti-obesity activity of RB and RB compounds is obligatory. Thus, the current manuscript was prepared to summarize the composition of RB and the influence of RB on the host microbiome, possible mechanisms, and preclinical and clinical studies on the anti-obesity properties of RB. This study suggested that the consumption of RB oil and dietary RB extracts might assist in managing obesity-associated health consequences. Further, extended clinical studies in several ethnic groups are required to develop dietary RB-based functional and nutritional supplements, which could serve as an adjuvant therapeutic strategy to treat obesity.

Recent Developments in Polyphenol Applications on Human Health: A Review with Current Knowledge

Polyphenol has been used in treatment for some health disorders due to their diverse health promoting properties. These compounds can reduce the impacts of oxidation on the human body, prevent the organs and cell structure against deterioration and protect their functional integrity. The health promoting abilities are attributed to their high bioactivity imparting them high antioxidative, antihypertensive, immunomodulatory, antimicrobial, and antiviral activity, as well as anticancer properties. The application of polyphenols such as flavonoids, catechin, tannins, and phenolic acids in the food industry as bio-preservative substances for foods and beverages can exert a superb activity on the inhibition of oxidative stress via different types of mechanisms. In this review, the detailed classification of polyphenolic compunds and their important bioactivity with special focus on human health are addressed. Additionally, their ability to inhibit SARS-CoV-2 could be used as alternative therapy to treat COVID patients. Inclusions of polyphenolic compounds in various foods have demonstrated their ability to extend shelf life and they positive impacts on human health (antioxidative, antihypertensive, immunomodulatory, antimicrobial, anticancer). Additionally, their ability to inhibit the SARS-CoV-2 virus has been reported. Considering their natural occurrence and GRAS status they are highly recommended in food.

The Phenolic Compounds' Role in Beer from Various Adjuncts

BACKGROUND

The present article considers the influence of malt with various adjuncts on beer organic compounds and taste profile composition, with more attention paid to the phenol complex change. The topic under consideration is relevant since it studies the interactions of phenolic compounds with other biomolecules, and expands the understanding of the adjuncts organic compounds contribution and their joint effect on beer quality.

METHODS

Samples of beer were analyzed at a pilot brewery using barley and wheat malts, barley, rice, corn and wheat, and then fermented. The beer samples were assessed by industry-accepted methods and using instrumental analysis methods (high-performance liquid chromatography methods-HPLC). The obtained statistical data were processed by the Statistics program (Microsoft Corporation, Redmond, WA, USA, 2006).

RESULTS

The study showed that at the stage of hopped wort organic compounds structure formation, there is a clear correlation between the content of organic compounds and dry substances, including phenolic compounds (quercetin, catechins), as well as isomerized hop bitter resines. It is shown that the riboflavin content increases in all adjunct wort samples, and mostly with the use of rice-up to 4.33 mg/L, which is 9.4 times higher than the vitamin levels in malt wort. The melanoidin content in the samples was in the range of 125-225 mg/L and its levels in the wort with additives exceeded the malt wort. Changes in β-glucan and nitrogen with thiol groups during fermentation occurred with different dynamics and depending on the adjunct's proteome. The greatest decrease in non-starch polysaccharide content was observed in wheat beer and nitrogen with thiol groups content-in all other beer samples. The change in iso-α-humulone in all samples at the beginning of fermentation correlated with a decrease in original extract, and in the finished beer there was no correlation. The behavior of catechins, quercetin, and iso-α-humulone has been shown to correlate with nitrogen with thiol groups during fermentation. A strong correlation was shown between the change in iso-α-humulone and catechins, as well as riboflavin and quercetin. It was established that various phenolic compounds were involved in the formation of taste, structure, and antioxidant properties of beer in accordance with the structure of various grains, depending on the structure of its proteome.

CONCLUSIONS

The obtained experimental and mathematical dependences make it possible to expand the understanding of intermolecular interactions of beer organic compounds and take a step toward predicting the quality of beer at the stage of using adjuncts.

Biotechnological interventions for improving the seed longevity in cereal crops: progress and prospects

Seed longevity is a measure of the viability of seeds during long-term storage and is crucial for germplasm conservation and crop improvement programs. Also, longevity is an important trait for ensuring food and nutritional security. Thus, a better understanding of various factors regulating seed longevity is requisite to improve this trait and to minimize the genetic drift during the regeneration of germplasm. In particular, seed deterioration of cereal crops during storage adversely affects agricultural productivity and food security. The irreversible process of seed deterioration involves a complex interplay between different genes and regulatory pathways leading to: loss of DNA integrity, membrane damage, inactivation of storage enzymes and mitochondrial dysfunction. Identifying the genetic determinants of seed longevity and manipulating them using biotechnological tools hold the key to ensuring prolonged seed storage. Genetics and genomics approaches had identified several genomic regions regulating the longevity trait in major cereals such as: rice, wheat, maize and barley. However, very few studies are available in other Poaceae members, including millets. Deploying omics tools, including genomics, proteomics, metabolomics, and phenomics, and integrating the datasets will pinpoint the precise molecular determinants affecting the survivability of seeds. Given this, the present review enumerates the genetic factors regulating longevity and demonstrates the importance of integrated omics strategies to dissect the molecular machinery underlying seed deterioration. Further, the review provides a roadmap for deploying biotechnological approaches to manipulate the genes and genomic regions to develop improved cultivars with prolonged storage potential.

Dietary Fibre Impacts the Texture of Cooked Whole Grain Rice

Consumers' general preference for white rice over whole grain rice stems from the hardness and low palatability of cooked whole grain rice; however, strong links have been found between consuming a large amount of white rice, leading a sedentary lifestyle, and acquiring type 2 diabetes. This led us to formulate a new breeding goal to improve the softness and palatability of whole grain rice while promoting its nutritional value. In this study, the association between dietary fibre profiles (using an enzymatic method combined with high-performance liquid chromatography) and textural properties of whole grain rice (using a texture analyser) was observed. The results showed that a variation in the ratio of soluble dietary fibre (SDF) and insoluble dietary fibre (IDF) influenced the textural characteristics of cooked whole grain rice; found a strong association between SDF to IDF ratio and hardness (r = -0.74, p < 0.01) or gumminess (r = -0.69, p < 0.01) of cooked whole grain rice, and demonstrated that the SDF to IDF ratio was also moderately correlated with cohesiveness (r = -0.45, p < 0.05), chewiness (r = -0.55, p < 0.01), and adhesiveness (r = 0.45, p < 0.05) of cooked whole grain rice. It is suggested that the SDF to IDF ratio can be used as a biomarker for breeding soft and highly palatable whole grain rice of cultivated tropical indica rice to achieve consumer well-being. Lastly, a simple modified method from the alkaline disintegration test was developed for high-throughput screening of dietary fibre profiles in the whole grain indica rice samples.

Identification and Isolation Techniques for Plant Growth Inhibitors in Rice

Plant growth inhibitors (PGIs) in rice (Oryza sativa), or rice allelochemicals, are secondary metabolites that are either exudated by rice plants to cope with natural competitors or produced during the decomposition of rice by-products in the paddy fields. Of these, the major groups of rice PGIs include phenolics, flavonoids, terpenoids, alkaloids, steroids, and fatty acids, which also exhibit potential medicinal and pharmaceutical properties. Recently, the exploitation of rice PGIs has attracted considerable attention from scientists worldwide. The biosynthesis, exudation, and release of PGIs are dependent on environmental conditions, relevant gene expression, and biodiversity among rice varieties. Along with the mechanism clarification, numerous analytical methods have been improved to effectively support the identification and isolation of rice PGIs during the last few decades. This paper provides an overview of rice PGIs and techniques used for determining and extracting those compounds from rice. In particular, the features, advantages, and limitations of conventional and upgraded extraction methods are comprehensively reported and discussed. The conventional extraction methods have been gradually replaced by advanced techniques consisting of pressurized liquid extraction (PLE), microwave-assisted extraction (MAE), and solid-phase extraction (SPE). Meanwhile, thin-layer chromatography (TLC), liquid chromatography (LC), gas chromatography (GC), mass spectrometry (MS), nuclear magnetic resonance (NMR), high-resolution mass spectrometry (HR-MS), infrared spectroscopy (IR), near-infrared spectroscopy (NIRS), and X-ray crystallography are major tools for rice PGI identification and confirmation. With smart agriculture becoming more prevalent, the statistics of rice PGIs and extraction methods will help to provide useful datasets for building an autonomous model for safer weed control. Conceivably, the efficient exploitation of rice PGIs will not only help to increase the yield and economic value of rice but may also pave the way for research directions on the development of smart and sustainable rice farming methods.

Effect of different doses of nitrogen fertilization on bioactive compounds and antioxidant activity of brown rice

Brown rice as a whole grain food is associated with various chronic diseases' reduced risks. In this study, the effects of different doses of nitrogen fertilization (0, 160, 210, 260, 315, and 420 kg N/ 100 m²) on bioactive compounds and antioxidant activity of brown rice (yanfeng47) were investigated. At nitrogen level of 210-260 kg N/100 m², the content of TFC (302.65 mg/100 g), β-sitosterol (1762.92 mg/100 g), stigmasterol (1358.735 mg/100 g), DPPH (74.57%), and OH free radical scavenging (74.19%) was the highest. The major phenolic acid was p-hydroxybenzoic acid. There were significant positive linear relationships between TFC (0.872, 0.843), β-sitosterol (0.896, 0.657), stigmasterol (0.543, 0.771), p-hydroxybenzoic acid (0.871, 0.875), and DPPH, OH antioxidant activity. These indicated that TFC and phytosterols were the most important components in brown rice that had strong antioxidant activity. Composite score of principal components indicated 210 Kg N/100 m² exhibited a more ideal dose of nitrogen for nutritional composition and antioxidant activity of brown rice.

Comparative analysis of the efficiency of seed protein profiles in assessing genetic variation and population structure among indigenous Manipur black rice cultivars

BACKGROUND

The state of Manipur, North East India has distinct topology of hill and valley regions with vast agroclimatic variability, being considered as one of the centers of rice diversity. The indigenous Manipur black rice cultivars exhibit wide range of diversity in morphology, pericarp color, shape and size of grain, aroma, glutinous or non-glutinous features but remain less characterised. Many of these cultivars, such as those named Chakhao, are endowed with multiple health benefits due to high anthocyanins, and hold special importance for the local people. It is important to analyse the genetic diversity and population structure for this germplasm with unique allelic combinations to utilize in rice breeding programme.

METHODS AND RESULTS

We characterized total soluble seed protein fractions to not only fingerprint the 45 indigenous black rice cultivars but assess their genetic relatedness. Cluster analyses generated mainly two groups, complemented by PCoA scatter plot ascertaining geographical distinction. The hill black rice were more diverse. The population structure analysis revealed seven subpopulations indicating high genetic variability. The 24 polymorphic bands were scored in the range of 127.8 to 10.3 kDa comprised of four protein fractions. Three polypeptide bands each were ascribed to known fractions of glutelins and prolamins, while one band each could be described for albumin and globulin fractions, besides other diagnostic bands.

CONCLUSION

Some diverse cultivars were Amubi, Chedo Anal, Chipi Buh, Athebu, Poireton, BuPu Mui, Kotha Chahao II. These cultivars can be used in future black rice breeding programmes. This can further prevent genetic erosion and protect intellectual property rights.

Protective Effect of Red Rice Extract Rich in Proanthocyanidins in a Murine Colitis Model

Inflammatory bowel disease (IBD) has become a global concern. Proanthocyanidin-rich red rice extract (PRRE) has been shown to suppress the inflammatory response in cellular cultures. However, the anti-colitis effect of PRRE has never been investigated in animals. This study aimed to examine the protective effect of the PRRE against dextran sulfate sodium (DSS)-induced colitis in mice. Male mice were orally administrated with PRRE of 50, 250 and 500 mg/kg/day for 21 days. Acute colitis was subsequently induced by administrated 2.5% DSS in drinking water for the final seven days. Sulfasalazine-treated mice were the positive group. All doses of PRRE and sulfasalazine significantly ameliorated DSS-induced severity of colitis, as indicated by decreasing daily activity index and restoring colon shortening. Treatments with PRRE, but not sulfasalazine, significantly reduced the histopathological index and infiltration of inflammatory cells. Furthermore, the PRRE treatments effectively improved mucous in colonic goblet cells using PAS staining, and suppressed the production of pro-inflammatory cytokines TNF-α, IL-1β and IL-6 induced by DSS, while sulfasalazine reduced only IL-1β and IL-6. This study suggested that PRRE had a greater anti-colitis effect than sulfasalazine. Thus, PRRE has a potential anti-colitis effect, and should be developed in a clinical trial as a natural active pharmaceutical ingredient for IBD.

Phenolic Profile and In Vitro Antioxidant Activity of Different Corn and Rice Varieties

Celiac disease (CD) is an autoimmune disease. To date, the only universally recognized treatment for CD is the gluten-free diet (GFD). Despite the GFD, a state of inflammation and oxidative stress could remain at the intestinal level of celiac patients. Several components of the diet, such as phenolic compounds with known antioxidant properties, could play a protective role in the inflammatory state of patients with CD. The objective of this study was the characterization of the phenolic profile and the antioxidant capacity of pigmented cereals (rice and corn) from the Italian market and farms. Different in vitro methods were applied: Folin-Ciocalteu assay, pH differential method, DPPH assay, TEAC assay, and High-Performance Thin Layer Chromatography technique. According to the results, pigmented varieties are possible valuable sources of phenolic compounds and anthocyanins with high antioxidant activity. They could be used as alternative ingredients for the formulation of gluten-free products.

Effect of extrusion parameters on the interaction between rice starch and glutelin in the preparation of reconstituted rice

Reconstituted rice produced by extrusion has been attracted attention due to nutritional fortification and convenient production. Nevertheless, how to achieve desirable qualities and physicochemical properties of reconstituted rice nearly to natural rice by regulating extrusion process parameters is difficult. Herein, rice starch/glutelin mixture as raw material of reconstituted rice was extruded at varying extrusion conditions. Specific mechanical energy (SME) and sectional expansion index (SEI) dropped with rise in density (R² = 0.9117 and 0.8207). Solubility was enhanced with increase in product temperature (R² = 0.9085), color darkened and shifted to reddish and yellowish as extrusion temperature increased (R² = 0.8577). These trends were well fitted by sigmoid models. Furthermore, SME enhanced hydrophobic and electrostatic interactions between rice starch and glutelin and caused the reduction in crystallinity and thermal stability, promoting the formation of a bi-continuous matrix of protein aggregates with rice starch. The obtained results can be applied to guide the production of reconstituted rice with desirable qualities.

Nutrigenomic Effects of White Rice and Brown Rice on the Pathogenesis of Metabolic Disorders in a Fruit Fly Model

Consumption of white rice (WR) has been shown to predispose individuals to metabolic disorders. However, brown rice (BR), which is relatively richer in bioactive compounds, possesses anti-glycaemic and antioxidant effects. In this study, fifteen cultivars of paddy rice that are predominantly consumed in North West Nigeria were analysed for their nutritional composition, bioactive contents and effects on metabolic outcomes in a fruit fly model. Gene expression analyses were conducted on the whole fly, targeting dPEPCK, dIRS, and dACC. The protein, carbohydrate, and fibre contents and bioactives of all BR cultivars were significantly different (p < 0.05) from the WR cultivars. Moreover, it was demonstrated that the glucose and trehalose levels were significantly higher (p < 0.05), while glycogen was significantly lower (p < 0.05) in the WR groups compared to the BR groups. Similarly, the expression of dACC and dPEPCK was upregulated, while that of dIRS was downregulated in the WR groups compared to the BR groups. Sex differences (p < 0.05) were observed in the WR groups in relation to the nutrigenomic effects. Our findings confirm metabolic perturbations in fruit flies following consumption of WR via distortion of insulin signalling and activation of glycogenolysis and gluconeogenesis. BR prevented these metabolic changes possibly due to its richer nutritional composition.

Cycloartenyl Ferulate Is the Predominant Compound in Brown Rice Conferring Cytoprotective Potential against Oxidative Stress-Induced Cytotoxicity

Since brown rice extract is a rich source of biologically active compounds, the present study is aimed to quantify the major compounds in brown rice and to compare their cytoprotective potential against oxidative stress. The content of the main hydrophobic compounds in brown rice followed the order of cycloartenyl ferulate (CAF) (89.00 ± 8.07 nmol/g) >> α-tocopherol (αT) (19.73 ± 2.28 nmol/g) > γ-tocotrienol (γT3) (18.24 ± 1.41 nmol/g) > α-tocotrienol (αT3) (16.02 ± 1.29 nmol/g) > γ-tocopherol (γT) (3.81 ± 0.40 nmol/g). However, the percent contribution of CAF to the radical scavenging activity of one gram of whole brown rice was similar to those of αT, αT3, and γT3 because of its weaker antioxidant activity. The CAF pretreatment displayed a significant cytoprotective effect on the hydrogen peroxide-induced cytotoxicity from 10 µM, which is lower than the minimal concentrations of αT and γT required for a significant protection. CAF also enhanced the nuclear factor erythroid 2-related factor 2 (Nrf2) nuclear translocation coincided with the enhancement of the heme oxygenase-1 (HO-1) mRNA level. An HO-1 inhibitor, tin protoporphyrin IX (SnPP), significantly impaired the cytoprotection of CAF. The cytoprotective potential of CAF is attributable to its cycloartenyl moiety besides the ferulyl moiety. These results suggested that CAF is the predominant cytoprotector in brown rice against hydrogen peroxide-induced cytotoxicity.