Antiproliferative potential and DNA scission inhibitory activity of phenolics from whole millet grains

Exploring the bioactive components of millets for their nutraceutical potential

Millets have gained significant attention in recent days due to their potential as nutritious and bioactive-rich food sources. Beyond their macronutrient content such as carbohydrates, fats, protein and minerals, possess impressive array of bioactive compounds viz., polyphenols, flavonoids and antioxidants. Ferulic acid is predominantly found among all the millets followed by caffeic acid and soluble/bound fractions of whole grains contain flavonoids. Their prebiotic properties contribute to gut health by promoting growth of beneficial gut microbiota. Phenolic compounds contribute to their antioxidant, anticancer and antiviral properties. Millets are rich in dietary fibre (15-20%), which has water absorbing and bulking property thereby increases transit time of food in the gut and helps in reducing risk of inflammatory bowel disease and acts as detoxifying agent in the body. The bioavailability of minerals is however hindered by the antinutritional factors like tannins and phytates. This review focuses on the nutraceutical potential of millets by exploring its bioactive components and its enhancement through biofortification strategies which is essential for utilizing and harnessing their health-promoting properties for the benefit of global nutrition and well-being.

Chemical Profile and Potential Application of Agri-food Waste Products for Counteracting Diabetes Induced Neuropathy in Rats

This study aimed to prepare defatted ethanol extract of Abelmoschus esculentus leaves, Morus nigra leaves and Punica granatum peel, to identify the chemical composition of these extracts and to explore their efficacy in counteracting diabetic neuropathy. LC-ESI-MS spectrometry was the hyphenated tool for component identification of these extracts. Behavioral, biochemical, and histopathological investigations were carried out after treatments of diabetic rats. The phenolic contents in the extracts are 16.38, 34.75 and 40.57 mg GAE/g extract regarding A. esculentus leaves, M. nigra leaves and P. granatum peel respectively. Chemodiversity of the phenolic contents was observed from the LC/Mass, where A. esculentus extract contained isoflavonoids and flavanones, M. nigra extract consisted of benzofurans, prenylated flavonoids, stilbenes, and xanthones, and P. granatum extract was rich in ellagitanins, condensed tannins, and anthocyanins. The extracts normalize of blood glucose levels, enhance the explorative behavior of the rats and their response time to thermal pain, restore the oxidant/antioxidant balance, attenuate inflammation, augment brain monoamines levels and modulate MAO-A and Ache enzyme activity. Furthermore, they recovered brain histopathological alterations. Conclusively, this study offers experimental evidence for the neuroprotective impact of studied defatted ethanol extracts against diabetic neuropathy via their hypoglycemic effect, antioxidant activity, and anti-inflammatory potential.

Characterization of the active components and bioaccessibility of phenolics in differently colored foxtail millets

Differently colored foxtail millet (Setaria italica) cultivars were compared regarding their amylose, B-complex vitamin, vitamin E, and phenolic compositions, as well as the bioaccessibility of their phenolics in simulated in vitro digestion. Dark-colored foxtail millets contained more thiamine, pyridoxine, and tocopherols, but less riboflavin, than light-colored ones. Phenolics were more abundant in dark-colored cultivars. Insoluble bound fractions accounted for 75%-83% of the total phenolics, with ferulic acid detected as the most plentiful compound. The major bioaccessible phenolic was free ferulic acid, with 100%-120% bioaccessibility, depending on cultivar, followed by p-coumaric acid and isoferulic acid (50%-80%). These relatively high bioaccessibilities were likely due to the release of soluble conjugated or insoluble bound phenolics during digestion. However, the contents of other free phenolics were largely decreased following in vitro digestion, resulting in low bioaccessibility, which also means that the release from the conjugated and bound fractions was poor.

Finger millet (Eleusine coracana L.): from staple to superfood-a comprehensive review on nutritional, bioactive, industrial, and climate resilience potential

MAIN CONCLUSION

This review discusses the Finger millet's rich nutritional profile, bioactive potential, and industrial applications, combined with its climate resilience, which make it a promising crop for enhancing food security and promoting sustainable agriculture. This review also highlights its significant potential to address malnutrition and mitigate climate change impacts. The emergence of Finger millet from "poor man's staple food" to "a nutrient rich cereal" has encouraged the need to explore this crop at a wider scale. It is a highly significant crop due to its rich nutritional and bioactive profile, diverse biological activities, and promising industrial applications, along with the high climate resilience. This comprehensive review evaluates its nutritional composition by comparing favorably with other cereals and millets and emphasizing its potential to address malnutrition and enhance food security. Furthermore, it explores the phytochemical/bioactive potential and strategies to enhance their bioavailability followed biological activities of Finger millet by highlighting its various health-promoting properties. The review also discusses industrial potential of finger millet including its role in nutraceutical and functional food production, as well as bioenergy generation. In addition, role of Finger millet as a climate-resilient crop; specifically, the available genetic resources and identification of genes and quantitative trait loci (QTLs) associated with major stress tolerance traits have also been discussed. By providing a comprehensive synthesis of existing knowledge, this study offers valuable insights for researchers, policymakers, and stakeholders engaged in efforts to promote sustainable agriculture, enhance food and nutrition security, and mitigate the impacts of climate change.

Review on Nutritional Potential of Underutilized Millets as a Miracle Grain

The current situation, which includes changes in eating habits, an increasing population, and the unrestricted use of natural resources, has resulted in a lack of resources that could be used to provide nourishing food to everyone. Natural plant resources are quickly being depleted, so it is necessary to consider new alternatives. In addition to the staple grains of rice and wheat, many other crops are being consumed that need to be utilized to their full potential and have the potential to replace the staple crops. Millets are one of the most important underutilized crops that have the potential to be used as a nutricereal. Millets have a high nutritional value, do not produce acids, do not contain gluten, and can contribute to a healthy diet. Due to a lack of awareness regarding the nutritional value of millets, their consumption is still restricted to the population that adheres to conventional diets and is economically disadvantaged even though millets contain a significant amount of nutrients. Millets are becoming increasingly unpopular due to a lack of processing technologies, food subsidies, and the inconvenience of preparing food with millets. Millets are a Nutricereal rich in carbohydrates, dietary fibers, energy, essential fatty acids, proteins, vitamin B, and minerals such as calcium, iron, magnesium, potassium, and zinc. These nutrients help to protect against post-translational diseases such as diabetes, cancer, cardiovascular disease, and celiac disease, among others. Millets are beneficial for controlling blood pressure, blood sugar level, and thyroid function; however, despite these functional properties, millets consumption has declined. Utilizing millets and other staple food crops to develop alternative food sources has become a new area of focus for businesses in the food industry. In addition, millet consumption can help foster immunity and health, which is essential in strengthening our fight against malnutrition in children and adolescents. In this article, the authors examine the potential of millets in terms of their nutricereal qualities.

Polyphenols from whole millet grain (Setaria italica) alleviate glucose and lipid homeostasis in diet-induced obese mice by increasing endogenous GLP-1

BACKGROUND

Foxtail millet (Setaria italica) is a whole millet grain that has been considered for improving the disorder of glucose and lipid metabolism. The purpose of the work is to explore the extraction and enrichment of polyphenols from foxtail millets which can regulate the disorder of glucose and lipid metabolism by increasing endogenous GLP-1 (glucagon-like peptide-1).

RESULTS

The optimum ultrasound-assisted extraction (UAE) of foxtail millet polyphenols (FMPs) was as follows: 70 °C and 400 W and 70% ethanol concentration, further purification using macroporous resin. In vitro, the FMP eluent of 60% ethanol (FMP-60) has the best effect in promoting GLP-1 secretion from L cells among the different active components of FMP. Millet polyphenols (MPs) were obtained from finishing foxtail millet with the bran removed by the same extraction and purification method. Compared with MP-60, FMP-60 mainly included eight active phenolic constituents and contained more ferulic acid, p-coumaric acid, 2-hydroxycinnamic acid, and coniferaldehyde. After gavage treatment of diet-induced obese (DIO) mice with FMP-60, FMP-60 promoted endogenous GLP-1 secretion in mice and ameliorated disorders of glucolipid metabolism in DIO mice.

CONCLUSION

FMP-60 could improve glucose homeostasis and ameliorates metabolic disease by promoting the endogenous GLP-1 level and preventing weight gain in DIO mice. © 2023 Society of Chemical Industry.

Varietal and processing influence on nutritional and phytochemical properties of finger millet: A review

Food and nutrition insecurity is a problem for the majority of developing nations; incidentally, some underutilized crops have the potential to increase food security. A minor cereal grain called finger millet (Eleusine coracana L.) is widely cultivated in various regions of India and Africa and is consumed for its numerous health advantages. There is a wealth of research on the nutritional and health benefits of this crop, but little is known about how varietal difference and processing affect these qualities. Therefore, this study reviewed the effects of variety and different processing methods on the nutrition, antinutrients, phytochemicals, and antioxidative properties of finger millet and its probable uses in ensuring nutrition and food security. Finger millet is a nutritious cereal with relatively high values of protein, vitamins, minerals, fibre, and energy. The amount of minerals, particularly calcium and potassium, is larger than what is found in the most popular grains, including wheat and rice. The grain of finger millet is non-glutinous and contains only 1.3% fat; in contrast to other types of millet which are noticeably higher in dietary fibre, protein, ash, and fat. The coloured varieties particularly have high levels of minerals, antioxidants, and phytochemicals. The nutritional and phytochemical qualities of finger millet are affected by the cultivars, varieties, and geographical locations. This study elucidates the qualities of finger millet varieties and methods of processing which will help in the selection of appropriate cultivars for food applications.

Isoflavone and Antioxidant of Instant Cream Soup Made from Pumpkin and Tempeh and Their Active Compound in Ovariohysterectomy Rat-Induced Alzheimer’s Disease

Menopause period associated with brain function disorders can caused by decreasing estradiol levels and increasing oxidative stress in the body. Antioxidant agents are required to balance oxidative stress in the body. Instant cream soup made from pumpkin and tempeh is a supplementary food containing isoflavone and antioxidant agents. This study is aimed at analyzing the content of antioxidant level and isoflavones (genistein and daidzein) in instant cream soup and their effect on ovariohysterectomy (OVx) rats. Instant pumpkin cream soup with and without tempeh were subjected to isoflavone content and antioxidant analysis. Serum estradiol was analyzed using enzyme-linked immunosorbent assay. Liver concentration of malondialdehyde (MDA) and activities of superoxide dismutase (SOD) were measured by spectrophotometric methods. The study showed that the isoflavone content (genistein 370.86 g/100 g, daidzein 185.61 g/100 g) was only present in the pumpkin instant cream soup with tempeh (IPTS). IPTS has higher antioxidant levels (134.25 mg AEAC/100 g) than instant pumpkin cream soup without tempeh (IPS). In vivo study, experimental rats showed that OVx increased malondialdehyde (MDA) levels up to 5.85-6.07 nmol mL-1 as compared to control (4.47 nmol mL-1). Moreover, instant pumpkin cream soup with tempeh treatments significantly increased serum estradiol levels (2.37–3.63 μg) and superoxide dismutase (SOD) levels of 497.49-558.89 U mL-1. This study concluded that instant pumpkin cream soup and tempeh contained isoflavone and antioxidant, and it increased estradiol serum and SOD level.

The endophytic fungus Penicillium oxalicum isolated from Ligusticum chuanxiong Hort possesses DNA damage-protecting potential and increases stress resistance properties in Caenorhabditis elegans

The chemical composition and antioxidant activity of extracts (POE) of Penicillium oxalate isolated from Ligusticum chuanxiong Hort have been investigated. However, the biological activity of POE is limited, and its antioxidant, stress resistance and DNA protection effects in vivo are unclear. The current study aims to explore the beneficial effects of POE on DNA damage protection in pBR322 plasmid and lymphocytes and stress resistance in Caenorhabditis elegans. The results showed that POE increased the survival rate of C. elegans under 35°C, UV and H₂O₂ stress, attenuated ROS and MDA accumulation, and enhanced the activity of some important enzymes (SOD, CTA, and GSH-PX). In addition, the POE-mediated stress resistance involved the upregulation of the expression of the sod-3, sod-5, gst-4, ctl-1, ctl-2, daf-16, hsp-16.1, hsp-16.2, and hsf-1 genes and acted dependently on daf-16 and hsf-1 rather than skn-1. Moreover, POE also reduced lipofuscin levels, but did not prolong the lifespan or damage the growth, reproduction and locomotion of C. elegans. Furthermore, POE showed a protective effect against DNA scission in the pBR322 plasmid and lymphocytes. These results suggested that P. oxalate extracts have significant anti-stress and DNA protection potential and could be potential drug candidates in the pharmaceutical field, thus greatly broadening the understanding of the biological effects of the endophytic fungus P. oxalate.

Effect of processing on the antioxidant activities of porridges and Pittu prepared from finger millets (Eleusine coracana)

Finger millets are important coarse grains that exhibit high levels of phenolic compounds and antioxidant activities among other cereals. Grains are subjected to a number of thermal treatments and this could affect the contents and bioactivities of phenolic compounds. The aim of the present study was to determine the phenolic contents and antioxidant activities of finger millet flour and foods, namely porridges and Pittu subjected to several thermal treatments such as roasting, parboiling, and parboiled roasting of flour and open boiling and steaming of foods prepared using flour. The effect of the addition of spices on phenolic content and antioxidant activities to open boiled foods was determined. Antioxidant activities of phenolic extracts obtained from finger millet flour and foods were studied for their total phenolic, flavonoids and proanthocyanidins contents, radical scavenging capacities, reducing power, ferrous ion chelating capacity, and antioxidant activity in a β-carotene/linoleate emulsion. The roasted flour and foods had higher total phenolic content (TPC) than other counterparts and ranged from 21.58 to 28.63 µmol ferulic acid equivalents/g dry matter. All flour and food preparations exhibited effective inhibition of radicals, reducing power, ferrous ion chelating activity, and antioxidant activity in the β-carotene/linoleate emulsion and the degree of activity depended on the processing conditions adopted in food preparations.

Foods prepared using steaming showed lower phenolic content and antioxidant activities in general than those of open-boiled counterparts. The addition of spices, namely garlic and cinnamon improved the phenolic contents and antioxidant activities of open-boiled porridges. The knowledge generated from this study may help to exploit the use of finger millets as a functional food ingredient to promote health and wellness.

Graphical abstract

Recent Developments in Fermented Cereals on Nutritional Constituents and Potential Health Benefits

Fermentation is one of the most economical and safe methods to improve the nutritional value, sensory quality and functional characteristics of raw materials, and it is also an important method for cereal processing. This paper reviews the effects of microbial fermentation on cereals, focusing on their nutritional value and health benefits, including the effects of fermentation on the protein, starch, phenolic compounds contents, and other nutrient components of cereals. The bioactive compounds produced by fermented cereals have positive effects on health regulation. Finally, the future market development of fermented cereal products is summarized and prospected.

Comparing the LC-MS Phenolic Acids Profiles of Seven Different Varieties of Brown Rice (Oryza sativa L.)

Brown rice, an important material of whole-grain food, is increasingly popular for its health benefits. Thus, seven varieties of brown rice from southern China were analyzed in this study, concerning the free and bound phenolic compounds in the extract. The phenolic profiles of different brown rice were obtained and compared by the combination of HPLC and LC-MS analysis, in which eleven phenolic acids were identified. It was indicated that the total phenolic contents of different brown rice varied from 92.32 to 196.54 mg of gallic acid equivalent (GAE)/100 g DW. Ferulic acid and p-coumaric acid, free and bound, dominated within the phenolic acids. To be mentioned, the total phenols of Luotiangongmi (a kind of red rice) were significantly higher than the other six varieties. The high phenolic content of brown rice can further guide us to explore the functional properties of the crops.

Effect of High-Pressure Processing (HPP) on Phenolics of North Atlantic Sea Cucumber (Cucumaria frondosa)

Sea cucumber contains a wide range of bioactive compounds, including phenolics. This study investigated the free, esterified, and insoluble-bound phenolics of sea cucumber body wall as affected by high-pressure processing (HPP) pretreatment. Sea cucumber body wall was subjected to HPP (200, 400, and 600 MPa for 5, 10, and 15 min), followed by the extraction of phenolics. The contents of total phenolics and antioxidant activity were monitored. Compared to untreated samples, those treated with HPP exhibited significantly higher total phenolics, flavonoids, and antioxidant activities. Treatment of 600 MPa for 10 min offered the optimal results. The highest amount of phenolics was observed in the free phenolic fraction, followed by esterified and insoluble-bound phenolic fractions. Moreover, phenolic extracts showed inhibitory effects against cupric ion-induced low-density lipoprotein (LDL)-cholesterol oxidation, peroxyl and hydroxyl radical-induced DNA scission, α-glucosidase activity, and formation of advanced glycation end products (AGEs). Ultra-high-performance liquid chromatography equipped with a quadrupole time of fight and mass spectrometer (UHPLC-QTOF-MS/MS) identified 20 phenolic compounds, mainly phenolic acids and flavonoids, from the body wall of this species for the first time. Thus, sea cucumber may lead to the production of a multitude of value-added products.

Phenolic Compounds and Antioxidant Capacity of Sea Cucumber (Cucumaria frondosa) Processing Discards as Affected by High-Pressure Processing (HPP)

Sea cucumber processing discards, which include mainly internal organs, represent up to 50% of the sea cucumber biomass, and are a rich source of bioactive compounds, including phenolics. This work aimed to extract free, esterified, and insoluble-bound phenolics from the internal organs of the Atlantic sea cucumber (C. frondosa) using high-pressure processing (HPP) pre-treatment. The sea cucumber internal organs were subjected to HPP (6000 bar for 10 min), followed by the extraction and characterization of phenolics. Samples were evaluated for their total contents of phenolics and flavonoids, as well as several in vitro methods of antioxidant activities, namely, free radical scavenging and metal chelation activities. Moreover, anti-tyrosinase and antiglycation properties, as well as inhibitory activities against LDL cholesterol oxidation and DNA damage, were examined. The results demonstrated that HPP pre-treatment had a significant effect on the extraction of phenolics, antioxidant properties, and other bioactivities. The phenolics in sea cucumber internal organs existed mainly in the free form, followed by the insoluble-bound and esterified fractions. Additionally, UHPLC-QTOF-MS/MS analysis identified and quantified 23 phenolic compounds from HPP-treated samples, mostly phenolic acids and flavonoids. Hence, this investigation provides fundamental information that helps to design the full utilization of the Atlantic sea cucumber species and the production of a multitude of value-added products.

Antioxidant Activity and Cytotoxicity against Cancer Cell Lines of the Extracts from Novel Xylaria Species Associated with Termite Nests and LC-MS Analysis

Xylaria species associated with termite nests or soil have been considered rare species in nature and the few which have been reported upon have been found to act as a rich source of bioactive metabolites. This study evaluated 10 ethyl acetate extracts of five new Xylaria species associated with termite nests or soil for their antioxidant activity, and cytotoxicity against different cancer and normal cell lines. DPPH and ABTS radical scavenging activities of the extracts demonstrated strong capacity with low IC₅₀ values. The highest observed activities belonged to X. vinacea SWUF18-2.3 having IC₅₀ values of 0.194 ± 0.031 mg/mL for DPPH assay and 0.020 ± 0.004 mg/mL for ABTS assay. Total phenolic content ranged from 0.826 ± 0.123 to 3.629 ± 0.381 g GAE/g crude extract which correlated with antioxidant activities. The high total phenolic content could contribute to the high antioxidant activities. Cytotoxicity was recorded against A549, HepG2, HeLa and PNT2 and resulted in broad spectrum to specific activity depending on the cell lines. The highest activities were observed with X. subintraflava SWUF16-11.1 which resulted in 11.15 ± 0.32 to 13.17 ± 2.37% cell viability at a concentration of 100 µg/mL. Moreover, LC-MS fingerprints indicated over 61 peaks from all isolates. There were 18 identified and 43 unidentified compounds compared to mass databases. The identified compounds were from various groups of diterpenoids, diterpenes, cytochalasin, flavones, flavonoids, polyphenols, steroids and derivatives, triterpenoids and tropones. These results indicate that Xylaria spp. has abundant secondary metabolites that could be further explored for their therapeutic properties.

Quenching effects of (-)-Epigallocatechin gallate for singlet oxygen production and its protection against oxidative damage induced by Ce6-mediated photodynamic therapy in vitro

BACKGROUND

Singlet oxygen (¹O₂) is highly reactive to biological components such as lipids, proteins and DNA, which induces oxidative damage to cells and tissues. Natural antioxidants may function as ¹O₂ quencher to prevent ¹O₂ involved photosensitized oxidation in biological system.

METHODS

Time-resolved measurement of ¹O₂ luminescence was employed to evaluate the ¹O₂ quenching abilities of natural antioxidants in air-statured phosphate buffered saline (PBS), including (-)-Epigallocatechin gallate (EGCG), Proanthocyanidins, L-carnosine and Vitamin C. The ¹O₂ quenching effects and rate constant of EGCG were investigated by detecting the absorption, fluorescence and ¹H-NMR spectroscopy and ¹O₂ luminescence decay curves, respectively. In addition, the protective activity of EGCG against ¹O₂ oxidative damage caused by Ce6-mediated photodynamic therapy (PDT) was verified in cells.

RESULTS

EGCG, proanthocyanidins, L-carnosine and Vitamin C efficiently quenched ¹O₂ luminescence at 1270 nm. The triplet-state quenching rate constants of EGCG for Rose Bengal (RB), Chlorin e6, AlPcS and HiPorfin are 2.21 × 10⁹, 4.90 × 10⁸, 3.30 × 10⁸, 1.78 × 10⁹ M^-1s^-1, while the ¹O₂ quenching rate constants are 2.80 × 10⁸, 1.50 × 10⁸, 1.30 × 10⁸, 1.70 × 10⁸ M^-1s^-1, respectively. Furthermore, EGCG could effectively quench ¹O₂ production to prevent NIH/3T3 cells oxidative damage induced by Ce6-mediated PDT.

CONCLUSIONS

EGCG is an efficient quencher for both triplet-state photosensitizers and ¹O₂. The quenching ability of EGCG during photosensitization for selected photosensitizers is: RB > HiPorfin > Ce6 > AlPcS. EGCG could be used to protect normal cells and tissue against oxidative damage.

Unraveling the Bioactive Profile, Antioxidant and DNA Damage Protection Potential of Rye (Secale cereale) Flour

Six different solvents were used as extraction medium (water, methanol, ethanol, acidified methanol, benzene and acetone) to check their phenolics extraction efficacy from flour of two rye cultivars. Rye extracts with different solvents were further analyzed for the estimation of phytochemicals and antioxidant properties. Different tests (TPC, TAC, DPPH, FRAP, ABTS, RPA and CTC) were performed to check the antioxidant properties and tannin contents in extracts. A bioactive profile of a rye cultivar indicated the presence of total phenolic compounds (0.08-2.62 mg GAE/g), total antioxidant capacity (0.9-6.8 mg AAE/g) and condensed tannin content (4.24-9.28 mg CE/100 g). HPLC was done to check phenolics in rye extract with the best solvent (water), which indicated the presence of Catechol (91.1-120.4 mg/100 g), resorcinol (52-70.3 mg/100 g), vanillin (1.3-5.5 mg/100 g), ferulic acid (1.4-1.5 mg/100 g), quercetin (4.6-4.67 mg/100 g) and benzoic acid (5.3 mg/100 g) in rye extracts. The presence of DNA damage protection potential in rye extracts indicates its medicinal importance. Rye flour could be utilized in the preparation of antioxidant-rich health-benefiting food products.

Phenolics Profile and Antioxidant Activity Analysis of Kiwi Berry (Actinidia arguta) Flesh and Peel Extracts From Four Regions in China

The kiwi berry (Actinidia arguta) has been widely studied because of its rich phenolic, flavonoid, and vitamin C contents. Numerous reports have demonstrated that fruit peels contain higher phenolic content and antioxidant activity than that of flesh. In this study, the phytochemical content and antioxidant activities of peel and flesh extracts of six kiwi berries were analyzed from four regions (namely, Dandong, Benxi, Taian, and Tonghua) in China. The antioxidant activity was determined using the peroxyl radical scavenging capacity (PSC) and cellular antioxidant activity (CAA) assays. The phenolic, flavonoid, and vitamin C contents of kiwi berry peel were 10.77, 13.09, and 10.38 times richer than that of kiwi berry flesh, respectively. In addition, the PSC and CAA values of kiwi berry peel were higher than those of kiwi berry flesh. The analysis of the separation and contents of phenolics were performed by the high-performance liquid chromatography (HPLC)-diode-array detectormass spectrometry/mass (DAD-MS/MS) system, and the results illustrated that protocatechuic acid, caffeic acid, chlorogenic acid, and quinic acid were the major phenolic compounds. In conclusion, this study indicated that kiwi berry peel contains a rich source of antioxidants. These data are of great significance for the full development and utilization of kiwi berries in these four regions of China to produce nutraceutical and functional foods.

Whole grain cereals: the potential roles of functional components in human health

Whole grain cereals have been the basis of human diet since ancient times. Due to rich in a variety of unique bioactive ingredients, they play an important role in human health. This review highlights the contents and distribution of primary functional components and their health effects in commonly consumed whole grain cereals, especially dietary fiber, protein, polyphenols, and alkaloids. In general, cereals exert positive effects in the following ways: 1) Restoring intestinal flora diversity and increasing intestinal short-chain fatty acids. 2) Regulating plasma glucose and lipid metabolism, thereby the improvement of obesity, cardiovascular and cerebrovascular diseases, diabetes, and other chronic metabolic diseases. 3) Exhibiting antioxidant activity by scavenging free radicals. 4) Preventing gastrointestinal cancer via the regulation of classical signaling pathways. In summary, this review provides a scientific basis for the formulation of whole-grain cereals-related dietary guidelines, and guides people to form scientific dietary habits, so as to promote the development and utilization of whole-grain cereals.

Determination of soluble and insoluble-bound phenolic compounds in dehulled, whole, and hulls of green and black lentils using electrospray ionization (ESI)-MS/MS and their inhibition in DNA strand scission

The soluble and insoluble-bound phenolic fractions of hull, whole, and dehulled black and green lentil extracts were identified and quantified using electrospray ionization (ESI)-MS/MS. Several in vitro antioxidant tests and inhibition of DNA strand scission were conducted to assess different pathways of activity. The most abundant phenolics in the soluble fractions were caffeic acid (412.2 μg/g), quercetin, (486.5 μg/g) quercetin glucoside (633.6 μg/g) luteolin glucoside (239.1 μg/g) and formononetin (920 μg/g), while myricetin (534.1 μg/g) and catechin (653.4 μg/g) were the predominant phenolics in the insoluble bound fraction. Hulls of both lentil cultivars had the highest phenolic content and the strongest antioxidant activity followed by whole and dehulled samples. Thus, lentil hulls would serve as an excellent source for the production of functional foods. Moreover, ESI-MS/MS (direct infusion) analysis was the rapid and high-throughput approach for the determination of bioactives in lentils by reducing the analysis time.

Valorization of Heat-Treated Brewers' Spent Grain Through the Identification of Bioactive Phenolics by UPLC-PDA and Evaluation of Their Antioxidant Activities

Thermal processing not only disrupts cell membranes and cell walls, but also cleaves covalent bonds releasing low molecular phenolic. This study examined the impact of various heat treatments (100, 140, and 160°C) on the composition of phenolic acids and antioxidant activities in extracts obtained from defatted brewers spent grain (BSG) meal. Heating BSG at 160°C resulted in a 2-fold increase in total phenolic content [TPC, 172.98 ± 7.3 mg Gallic acid equivalent (GAE)/100 g defatted meal] and total flavonoid content [TFC, 16.15 ± 2.22 catechin equivalents (CE)/100 g defatted meal] compared to the untreated BSG extracts. The antioxidant activities of treated BSG extracts, determined by radical scavenging and ferric reducing antioxidant power (FRAP) were significantly (p < 0.5) higher than the corresponding untreated BSG extracts. Eleven phenolic acids were identified and quantified in BSG extracts by Ultra Performance Liquid Chromatography with Photodiode Array (UPLC-PDA). The amounts varied significantly (p < 0.05) depending on the degree of toasting BSG was subjected to. Chlorogenic acid, an ester of caffeic and quinic acid was the predominant phenolic acid present in all fractions. Significant (p < 0.05) increases in TPC, TFC, individual phenolic acids and antioxidant activity were observed in BSG extracts exposed to increasing oven temperatures. These results confirm the ability of heat processing to release bioactive phenolic from their bound forms thereby enhancing the phenolic acids and the digestibility of BSG meal in the intestinal tract.

Polyphenol from millet bran increases the sensitivity of colorectal cancer cells to oxaliplatin by blocking the ganglioside GM3 catabolism

The study implies that bound polyphenol from millet bran dramatically prevents ganglioside GM3 catabolism followed by the suppression of P-gp, which eventually reverse drug-resistance in colorectal cancer cells to oxaliplatin.

Identifying Anti-Oxidant Biosynthesis Genes in Pearl Millet [Pennisetum glaucum (L.) R. Br.] Using Genome-Wide Association Analysis

Pearl millet [Pennisetum glaucum (L.) R Br.] is an important staple food crop in the semi-arid tropics of Asia and Africa. It is a cereal grain that has the prospect to be used as a substitute for wheat flour for celiac patients. It is an important antioxidant food resource present with a wide range of phenolic compounds that are good sources of natural antioxidants. The present study aimed to identify the total antioxidant content of pearl millet flour and apply it to evaluate the antioxidant activity of its 222 genotypes drawn randomly from the pearl millet inbred germplasm association panel (PMiGAP), a world diversity panel of this crop. The total phenolic content (TPC) significantly correlated with DPPH (1,1-diphenyl-2-picrylhydrazyl) radical scavenging activity (% inhibition), which ranged from 2.32 to 112.45% and ferric-reducing antioxidant power (FRAP) activity ranging from 21.68 to 179.66 (mg ascorbic acid eq./100 g). Genome-wide association studies (GWAS) were conducted using 222 diverse accessions and 67 K SNPs distributed across all the seven pearl millet chromosomes. Approximately, 218 SNPs were found to be strongly associated with DPPH and FRAP activity at high confidence [-log (p) > 3.0-7.4]. Furthermore, flanking regions of significantly associated SNPs were explored for candidate gene harvesting. This identified 18 candidate genes related to antioxidant pathway genes (flavanone 7-O-beta-glycosyltransferase, GDSL esterase/lipase, glutathione S-transferase) residing within or near the association signal that can be selected for further functional characterization. Patterns of genetic variability and the associated genes reported in this study are useful findings, which would need further validation before their utilization in molecular breeding for high antioxidant-containing pearl millet cultivars.

Phenolic acid bound arabinoxylans extracted from Little and Kodo millets modulate immune system mediators and pathways in RAW 264.7 cells

The immunomodulating effect of Phenolic acid bound arabinoxylans (PCA-AXs) extracted from Little (PCA-AX-L) and Kodo (PCA-AX-K) millet seeds in RAW 264.7 cells were investigated. The PCA-AXs were extracted from millets and their chemical characterization were carried out by GC-MS, HPLC, and FT-IR. The immunomodulatory effect of PCA-AXs in RAW 264.7 cells were investigated by estimating ROS, NO, and cytokines TNF-α, IL-1β, IL-6, and evaluation of molecular mechanism by q-PCR & western blotting techniques. The xylose: arabinose ratio of PCA-AX-L and PCA-AX-K were 1.48:1.0 and 2.26:1.0, respectively. The phenolic acids content was higher in PCA-AX-K than PCA-AX-L determined by HPLC. FT-IR analysis confirms the presence of α-glucosidic linkage with the degree of substitution of xylan backbone by arabinose residues. The evaluation of immunomodulating effect of PCA-AXs revealed that the PCA-AX-L-treated cells showed higher release of NO, ROS and cytokines than PCA-AX-K-treated cells. The mRNA expressions of TNF-α, iNOS and COX-2 were upregulated by PCA-AX-L and downregulated by PCA-AX-K in dose-dependent manner. Furthermore, in western blotting, the ERK and NF-κB were found to be activated by PCA-AX-L and inhibited by PCA-AX-K. Our findings suggest that the high branched arabinoxylans of PCA-AX-L could modulate the immune response in RAW 264.7 cells through activation of ERK and NF-κB signaling pathways and acts as an immunostimulant. The higher phenolic content in PCA-AX-K could modulate the immune response by downregulation of ERK and NF-κB signaling pathways and thus, it could act as an immunomodulator. PRACTICAL APPLICATIONS: Millets are the richest source of arabinoxylans in which they are known to be bound with phenolic acids (PCA-AX). Arabinoxylans derived from rice and wheat is known immunomodulators. This study was focused to evaluate the immunomodulatory property of PCA-AX derived from two different millets little and kodo. The study results clearly indicated the immune stimulatory action of PCA-AX-L and immunomodulatory action of PCA-AX-K. The explored mechanism indicated that the PCA-AXs modulate NF-κB & ERK pathways for their immunomodulatory action.

Assessment of the phenolic compounds of pearl and finger millets obtained from South Africa and Zimbabwe

Millet grains are rich in phenolic compounds which have health benefits. This study aims to elucidate the phenolic properties of pearl and finger millet grown in South Africa and Zimbabwe. The milled samples were analyzed by Waters Synapt G2 Quadrupole time-of-flight (QTOF) mass spectrometer (MS). A total of eight phenolic compounds were detected and quantified in the millet varieties, which included derivatives of benzoic acid such as protocatechuic and p-hydroxybenzoic acids. Flavonoids such as catechin, epicatechin, procyanidin B1, procyanidin B2, and kaempferol glycoside were also detected. Generally, catechin was the dominant phenolic compound, followed by epicatechin. The mean values for catechin ranged from 2.50 to 12.6 mg/kg for the pearl millet and 610.4 to 675.1 mg/kg for the finger millet. While the epicatechin mean values ranged between 1.2 to 1.8 for pearl millet and 99.1 to 139.5 for finger millet. Procyanidins B1 and B2 were only detected and quantified in the finger millet types, While Kaempferol glycoside was only recorded in the pearl millets with mean values of 196.0 mg/kg for pearl millet South Africa and 213.6 mg/kg for pearl millet Zimbabwe. There was a difference among the varieties for the content of kaempferol glycoside. Protocatechuic and p-hydroxybenzoic acids were only present in the finger millet types, their mean values were (20.9, 23.7 mg/kg) and (16.8,13.5 mg/kg) respectively. It can be substantiated from the outcome of this study that millet can be used as a source of valuable phenolic compounds and that the variety of millet is the determining factor of the phenolic compound content.

Phenolic Profile, Antioxidant, and Antidiabetic Potential Exerted by Millet Grain Varieties

This study evaluated the potential antioxidant and antidiabetic properties in vitro of four millet grain varieties cultivated in South Korea. The free fractions were tested for their total antioxidant capacity using 2,2′-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS⁺) and 2,2′-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assays, followed by α-glucosidase, α-amylase, and advanced glycation endproducts (AGEs) formation inhibition assays. The total phenolics, flavonoids, and condensed tannins in the free fractions ranged from 107.8 to 136.4 mg ferulic acid equivalent (FAE)/100 g, 101.3 to 115.8 mg catechin equivalent (CE)/100 g, and 17.65 to 59.54 mg catechin equivalent (CE)/100 g, respectively. Finger Italian millet had the highest total phenolic content (136.4 mg FAE/100 g) and flavonoid content (115.8 mg CE/100 g). Barnyard and finger Italian millet showed the highest DPPH (IC₅₀ = 359.6 µg/mL and 436.25 µg/mL, respectively) and ABTS radical scavenging activity (IC₅₀ = 362.40 µg/mL and 381.65 µg/mL, respectively). Similarly, finger Italian millet also exhibited significantly lower IC₅₀ values for the percentage inhibition of α-glucosidase (18.07 µg/mL) and α-amylase (10.56 µg/mL) as compared with acarbose (IC₅₀ = 59.34 µg/mL and 27.73 µg/mL, respectively) and AGEs formation (33.68 µg/mL) as compared with aminoguanidine (AG) (52.30 µg/mL). All eight phenolic compounds identified in finger Italian millet were flavonoids, with flavanols being the predominant subclass. Taken together, millet flavonoids play important roles in the prevention and management of type 2 diabetes, and hence finger Italian millet has the potential to be developed as a functional food.

Screen for Potential Candidate Alternatives of Sargentodoxa cuneata from Its Six Adulterants Based on Their Phenolic Compositions and Antioxidant Activities

Daxueteng, the liana stem of Sargentodoxa cuneata, is a widely used Traditional Chinese Medicine facing the overflow of its commercial adulterants. A method for discriminating adulterants and screening potential candidate alternatives of S. cuneata was thus established. Total phenols and flavonoids of S. cuneata and its six adulterants and their abilities to scavenge DPPH^• and ABTS•+, to absorb peroxyl radicals (ORAC), and to inhibit AAPH-induced supercoiled plasmid DNA strand scission were comprehensively assessed. Polygonum cuspidatum and Bauhinia championii, two of the six adulterants of S. cuneate, shared considerably higher antioxidant activities as well as phenolic contents and, therefore, were considered as potential candidate alternatives. Phenolic compositions of the two potential candidate alternatives and S. cuneata itself were further determined by UPLC-QTOF-MS/MS. Totally 38 phenolics, including four hydroxybenzoic acids, two tyrosols, two caffeoylquinic acids, seven flavanol or its oligomers, two lignans, three hydroxycinnamic acids, six stilbenes, seven anthraquinones, and five flavanones were determined from three species. Furthermore, contents of different phenolic categories were semi-quantified and the major antioxidant contributors of S. cuneata and the two potential candidate alternatives were subsequently determined. It is concluded that tyrosols and caffeoylquinic acids were unique categories making great antioxidant contributions in S. cuneata and thus were considered as effective biomarkers in distinguishing its potential candidate alternatives.

An aqueous polyphenol extract from Rosa rugosa tea has antiaging effects on Caenorhabditis elegans

Rosa rugosa aqueous polyphenol (RAP) is a kind of polyphenol from Rosa rugosa flower tea. In this study, the antiaging activities of RAP were studied in the model organism Caenorhabditis elegans. UHPLC-HESI-MS/MS was employed to identify the specific phenolic profile, revealing that there were 23 types of phenolic compounds in RAP and that quercetin glycoside was the principal component. RAP increased the mean lifespan of C. elegans and enhanced the thermotolerance and resistance to oxidative stress of C. elegans in a concentration-dependent manner. Furthermore, RAP showed powerful antioxidant effects in vitro and strong protection against oxidative DNA damage. RAP significantly improved the levels of total superoxide dismutase and total antioxidant capacity of C. elegans. In conclusion, RAP has antiaging effects on C. elegans, which might be related to its powerful antioxidant effects both in vitro and in vivo. PRACTICAL APPLICATIONS: In recent years, chronic diseases associated with aging have had a profound impact on quality of life. Many healthy foods have antiaging properties, especially flower teas, such as those made from Rosa rugosa. Our results indicated that Rosa rugosa tea is good for health and that RAP could potentially be developed as a bioactive product that could be used to combat aging.

Transcriptome-wide identification of genes involved in Ascorbate-Glutathione cycle (Halliwell-Asada pathway) and related pathway for elucidating its role in antioxidative potential in finger millet (Eleusine coracana (L.))

Finger millet is being recognized as a potential future crop due to their nutrient contents and antioxidative properties, which are much higher compared to the other minor millets for providing health benefits. The synthesis of these nutritional components is governed by the expression of several gene(s). Therefore, it is necessary to characterize these genes for understanding the molecular mechanisms behind de novo synthesis of nutrient components. Apart from this, these important compounds could also serve as candidate genes for imparting stress tolerance in other crop plants also. In the present study, effort has been made to identify genes involved in Ascorbate-Glutathione cycle (Halliwell-Asada Pathway) and related pathway genes for elucidating its role in antioxidative potential mechanism through transcriptome data analysis. APX, DHAR, MDHAR, GR, and SOD have been identified as the key genes of the pathway in two genotypes GP-1 (low Ca²⁺) and GP-45 (high Ca²⁺) of finger millet with reference to rice as a model system, besides, 30 putatively expressed genes/proteins were also investigated. Furthermore, the sequences of identified genes were analyzed systematically; gene ontology (GO) annotation and enrichment analysis of assembled unitranscripts were also performed using Blast2GO. As a result, 49 GO terms, 5 Enzyme Commission (EC) numbers, and 2 KEGG pathway maps were generated. GO results revealed that these genes are mainly involved in two biological processes (BP), viz., oxidation-reduction process (GO:0055114) and cellular oxidant detoxification (GO:0098869), and showed oxidoreductase activity (GO:0016491). KEGG analysis showed that APX, DHAR, MDHAR, and GR are directly connected to biosynthetic pathways of secondary metabolites, mainly polyphenolic compounds (flavonoid, tannin, and lignin) involved in glutathione metabolism (KEGG:00480) and ascorbate and aldarate metabolism (KEGG:00053). While SOD, is indirectly connected and also has significant medicinal attributes and antioxidant properties. Moreover, Fragments Per Kilobase of transcript per Million mapped reads (FPKM) values were also calculated for expression analysis and found that the FPKM values of genes present in GP-1 are higher than that of GP-45. Thus, GP-1 genotype was found to have higher stress regulated gene expression in comparison to GP-45. Taken together, the present transcriptome-based investigation unlocks new avenues for systematic functional analysis of novel ROS scavenging candidate genes that could be effectively applied for improvising human health and nutrition.

Profile of phenolic compounds and antioxidant activity of finger millet varieties

The profiles of phenolic compounds and antioxidant capacities of four finger millet varieties harvested in northern Malawi were investigated. The total phenolics, flavonoids and condensed tannins in the free fractions ranged from 114.43 to 179.19 mg ferulic acid equivalent (FAE)/100 g, 90.24 to 202.94 mg catechin equivalent (CE)/100 g and 31.76 to 83.59 mg CE/100 g, respectively. Total phenolic contents of the bound fractions ranged from 58.27 to 123.23 mg FAE/100 g. Twenty phenolic compounds were identified in the free fractions including eighteen flavonoids, with catechin and epicatechin being the predominant flavonoids. Seventeen phenolic compounds were identified in the bound fractions, with ferulic acid being the predominant one. Ten of the identified polyphenols were firstly reported in finger millet. Darker colored finger millet varieties had higher phenolic contents and antioxidant properties than the lighter colored ones. Finger millet can be used as healthy food material and natural antioxidant resource.

A full utilization of rice husk to evaluate phytochemical bioactivities and prepare cellulose nanocrystals

Rice husks (RHs) as an agro-waste generated from rice production, while its application is limited. This study was designed to introduce a full utilization of rice husks, which extracted the phytochemical at first and then produced cellulose nanocrystals (CNCs) as the use of the residue. Furthermore, the phytochemicals extracted from rice husk was identified and its biological activity, including antioxidant activity, cellular antioxidant activity (CAA) and antiproliferative activity, had been detected as well. Results showed the bound fraction of rice husk had higher antioxidant than common fruit and grain. Free fraction of rice husk deserved to have further analysis in antiproliferative activity due to its low cytotoxicity. The CNCs produced by residue was using delignification process and acid hydrolysis treatments. The chemical composition of the residue obtained after phytochemical extraction was determined. CNCs morphological investigation was performed using an optical microscope and atomic force microscopy (AFM). Our strategy is to achieve a comprehensive utilization of rice husks with both economy and environment benefits.

African Orphan Crops under Abiotic Stresses: Challenges and Opportunities

A changing climate, a growing world population, and a reduction in arable land devoted to food production are all problems facing the world food security. The development of crops that can yield under uncertain and extreme climatic and soil growing conditions can play a key role in mitigating these problems. Major crops such as maize, rice, and wheat are responsible for a large proportion of global food production but many understudied crops (commonly known as "orphan crops") including millets, cassava, and cowpea feed millions of people in Asia, Africa, and South America and are already adapted to the local environments in which they are grown. The application of modern genetic and genomic tools to the breeding of these crops can provide enormous opportunities for ensuring world food security but is only in its infancy. In this review, the diversity and types of understudied crops will be introduced, and the beneficial traits of these crops as well as their role in the socioeconomics of Africa will be discussed. In addition, the response of orphan crops to diverse types of abiotic stresses is investigated. A review of the current tools and their application to the breeding of enhanced orphan crops will also be described. Finally, few examples of global efforts on tackling major abiotic constraints in Africa are presented.