Bound phenolics in foods, a review

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.

Plant- and Animal-Based Antioxidants' Structure, Efficacy, Mechanisms, and Applications: A Review

Antioxidants are compounds that normally prevent lipid and protein oxidation. They play a major role in preventing many adverse conditions in the human body, including inflammation and cancer. Synthetic antioxidants are widely used in the food industry to prevent the production of adverse compounds that harm humans. However, plant- and animal-based antioxidants are more appealing to consumers than synthetic antioxidants. Plant-based antioxidants are mainly phenolic compounds, carotenoids, and vitamins, while animal-based antioxidants are mainly whole protein or the peptides of meat, fish, egg, milk, and plant proteins. Plant-based antioxidants mainly consist of aromatic rings, while animal-based antioxidants mainly consist of amino acids. The phenolic compounds and peptides act differently in preventing oxidation and can be used in the food and pharmaceutical industries. Therefore, compared with animal-based antioxidants, plant-based compounds are more practical in the food industry. Even though plant-based antioxidant compounds are good sources of antioxidants, animal-based peptides (individual peptides) cannot be considered antioxidant compounds to add to food. However, they can be considered an ingredient that will enhance the antioxidant capacity. This review mainly compares plant- and animal-based antioxidants’ structure, efficacy, mechanisms, and applications.

Anti-Osteoporotic Effect of Viscozyme-Assisted Polysaccharide Extracts from Portulaca oleracea L. on H2O2-Treated MC3T3-E1 Cells and Zebrafish

This study aims to screen and characterize the protective effect of polysaccharides from Portulaca oleracea L. (POP) against H2O2-stimulated osteoblast apoptosis in vivo and in vitro. The enzymes viscozyme, celluclast, α-amylase, and β-glucanase were used to extract POPs. Among all enzyme-assisted POPs, the first participating fraction of viscozyme extract POP (VPOP1) exhibited the highest antioxidant activity. Hoechst 33342 and acridine orange/ethidium bromide staining and flow cytometry of MC3T3 cells revealed that VPOP1 inhibited apoptosis in a dose-dependent manner. Moreover, VPOP1 increased the expression levels of heme oxygenase-1 (HO-1) and NADPH quinine oxidoreductase 1 (NQO1) and decreased the expression levels of nuclear factor (erythroid-derived 2)-like 2 (Nrf2) and Kelch-like ECH-associated protein 1 (Keap1) in H2O2-induced cells compared with their controls. The results of an in vivo experiment show that VPOP1 significantly reduced reactive oxygen species generation and lipid peroxidation in zebrafish at 72 h post-fertilization and promoted bone growth at 9 days post-fertilization. Furthermore, VPOP1 was identified via 1-phenyl-3-methyl-5-pyrazolone derivatization as an acidic heteropolysaccharide comprising mannose and possessing a molecular weight of approximately 7.6 kDa. Collectively, VPOP1 was selected as a potential anti-osteoporotic functional food because of its protective activity against H2O2-induced damage in vitro and in vivo.

Comparison and Optimization of Different Extraction Methods of Bound Phenolics from Jizi439 Black Wheat Bran

Diet rich in phenolics would potentially associate with multiple health benefits. Response surface methodology (RSM) was introduced to optimize the process of ultrasound- and microwave-assisted extraction of bound phenolics from the bran of a newly developed black wheat breeding line Jizi439 and then compared with the traditional alkaline method. The optimum conditions were found to be 66 °C, 48 min, and power 240 W for ultrasound-assisted extraction (UAE), and 120 s, power 420 W for microwave-assisted extraction (MAE), respectively. Total bound phenolic contents (TBPCs), determined by Folin-Ciocalteu reagent, were 8466.7 ± 240.9 μg gallic acid equivalents per gram (μg GAE/g) bran for UAE and 8340.7 ± 146.7 μg GAE/g bran for MAE under optimized conditions, which were both significantly higher than that of the traditional method (5688.9 ± 179.6 μg GAE/g) (p < 0.05). Antioxidant activities (AAs) were determined by DPPH and ABTS methods. UAE extracts showed the highest DPPH scavenging activity (77.5 ± 0.9%), while MAE extracts showed the highest ABTS scavenging activity (72.1 ± 0.6%). Both were significantly higher than that of the traditional method (69.6 ± 1.1% for DPPH and 65.9 ± 0.5% for ABTS) (p < 0.05). Total bound phenolics (TBPs) profiles were further analyzed by HPLC, and results indicated that ferulic acid was dominant, followed by vanillic acid and p-coumaric acid. The contents of each identified individual phenolics were significantly increased by ultrasound and microwave. In conclusion, UAE and MAE were comparable with each other in TBP yields and AAs; however, when taking operation time and energy consumption into consideration, MAE was more efficient than UAE. Our study suggested efficiency extraction methods for further use of bound phenolics as a healthy food ingredient.

Uses of ionic liquids to obtain bioactive compounds: insights from the main international regulations for technological applications

Ionic liquids (IL) are innovative alternative solvents to recover bioactive compounds from plant-based sources to replace toxic volatile organic solvents (VOS). ILs are tailored-made solvents with chemical and thermal stabilities, nonvolatile and noninflammable. Although ILs are versatile, cost-effective, and sustainable solutions, the European Commission (EC) has no current regulation to approve extracts obtained with ILs to be applied in foods. Herein, this paper aims to assess the overview of ILs, regulamentation, applications, and its toxic effects, to be used as solvents for extract different bioactive compounds. Studies have suggested novel applications for ILs, such as 1-butyl-3-methylimidazolium bromide, 1-butyl-3-methylimidazolium chloride, 1-butyl-3-methylimidazolium tetrafluoroborate and others, to obtain bioactive compounds, for instance phenolic compounds, lignans, alkaloids, carotenoids, polysaccharides, using modern approaches as ultrasound and microwave-assisted extraction. New IL methods increase the efficiency of recovering target compounds and decrease the extraction time and VOS consumption regarding the traditional techniques. Furthermore, to promote the large-scale use of IL in foods, it is essential to investigate individually the toxicity of each IL used in the extraction processes, aiming to obtain a GRAS stamp, due to the currently lack of regulamentation.

Sweet corn cob as a functional ingredient in bakery products

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Incorporation of sweet corn cob flour (SCCF) in gluten free rice muffin was examined.

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SCCF contained a higher amount of ferulic acid and dietary fiber than rice flour.

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Muffin incorporated with 10% and 20% of SCCF showed an improvement in texture.

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Baking increases the free ferulic acid in muffin incorporated with SCCF.

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Muffin with SCCF showed higher mean overall liking scores in consumers liking test.

Gluten free (GF) products are often inferior in quality attributes, nutritional content and consumer acceptability. The use of GF by-products is a novel strategy to improve the structure and nutritional profile of these products. Sweet corn cob (SCC) is a by-product of sweet corn processing containing a considerable amount of fibre and ferulic acid. The effect of baking on ferulic acid content, colour, texture and physical characteristics on muffins incorporated with SCC flour (SCCF) as a value-added food ingredient was investigated using a GF model system. The freeze-dried SCCF, containing ferulic acid (6.02 mg g⁻¹) was used to replace the rice flour at varying levels of 10, 20, and 30%. In general, SCCF increased dietary fibre and free ferulic acid content of muffins. Inclusion of 20% SCCF showed an increase in terms of the height of the muffin and number of air cells in the crumb, along with a decrease in the hardness of muffins. Muffins with SCCF showed higher mean overall liking scores than rice flour muffin.

In Vitro Oxidative Stress Threatening Maize Pollen Germination and Cytosolic Ca2+ Can Be Mitigated by Extracts of Emmer Wheatgrass Biofortified with Selenium

In this work, we studied the effects of in vitro oxidative stress applied by H₂O₂ to maize pollen germination and cytosolic Ca²⁺, taken as an experimental model to test the biological activity of extracts of emmer (Triticum turgidum L. spp. dicoccum (Schrank ex Shubler) Thell.) wheatgrass obtained from grains sprouted with distilled water, or salinity (50 mM) or selenium (45 mg L^-1 of Na₂SeO₃). Wheatgrass extracts were obtained in two ways: by direct extraction in methanol, which represented the free phenolic fraction of extracts (Ef), and by residual content after alkaline digestion, which made it possible to obtain extracts with the bound fraction (Eb). Comparative tests on maize pollen were carried out by differently combining H₂O₂ and either wheatgrass extracts or pure phenolic acids (4-HO benzoic, caffeic, p-coumaric and salicylic). The cytosolic Ca²⁺ of maize pollen was influenced by either H₂O₂ or pure phenolic acids or Ef, but not by Eb. The negative effect of H₂O₂ on maize pollen germination and cytosolic Ca²⁺ was mitigated by Ef and, slightly, by Eb. The extent of the biological response of Ef depended on the sprouting conditions (i.e., distilled water, salinity or selenium). The extracts of Se-biofortified wheatgrass were the most effective in counteracting the oxidative stress.

Hydrolyzed Bound Phenolics from Rice Bran Alleviate Hyperlipidemia and Improve Gut Microbiota Dysbiosis in High-Fat-Diet Fed Mice

It has been confirmed the lipid-lowering effect of rice bran free phenolics, but it is unknown whether rice bran bound phenolics, the phenolic profile of which differs from the free ones, have a similar effect. Thus, the hypolipidemic effect and potential mechanism of hydrolyzed bound phenolics (HBP) from rice bran was investigated in this study. The results showed that HBP supplementation significantly improved serum lipid profiles of high-fat-diet fed mice. HBP inhibited the activation of nuclear receptors liver X receptor-α (LXRα), sterol regulatory element binding protein 1c (SREBP-1c), and peroxisome proliferators-activated receptors-γ (PPARγ), and, therefore, changed the expressions of their downstream genes, including LDLR, CD36, ACC1, FAS, and DGAT2 in the liver. Moreover, HBP supplementation reversed the high-fat-diet induced gut microbiota dysbiosis. These findings suggest that HBP might alleviate the hyperlipidemia via inhibiting the hepatic de novolipogenesis, regulating the uptake of cholesterol and fatty acid in the liver and their absorption in the gut. The attenuation of microbiota dysbiosis might contribute to the above effects.

Overview of fermentation process: structure-function relationship on protein quality and non-nutritive compounds of plant-based proteins and carbohydrates

Demands for high nutritional value-added food products and plant-based proteins have increased over the last decade, in line with the growth of the human population and consumer health awareness. The quality of the plant-based proteins depends on their digestibility, amino acid content, and residues of non-nutritive compounds, such as phenolic compounds, anti-nutritional compounds, antioxidants, and saponins. The presence of these non-nutritive compounds could have detrimental effects on the quality of the proteins. One of the solutions to address these shortcomings of plant-based proteins is fermentation, whereby enzymes that present naturally in microorganisms used during fermentation are responsible for the cleavage of the bonds between proteins and non-nutritive compounds. This mechanism has pronounced effects on the non-nutritive compounds, resulting in the enhancement of protein digestibility and functional properties of plant-based proteins. We assert that the types of plant-based proteins and microorganisms used during fermentation must be carefully addressed to truly enhance the quality, functional properties, and health functionalities of plant-based proteins.Supplemental data for this article is available online at here. show.

Relative Assessment of Biochemical Constituents and Antioxidant Potential of Fermented Wheat Grains Using Bacillus subtilis KCTC 13241

High antioxidant levels in food are gradually becoming popular because of enhanced risk of oxidative stress in humans. Bread wheat is rich in vital antioxidants, but a major portion of its bioactive compounds are not available to humans. This study was conducted with the aim to fulfill the antioxidants and nutrients gap between the available and potential levels of wheat grains through fermentation by Bacillus subtilis KCTC 13241. In this experiment, the whole wheat grains were used by keeping in consideration the importance of minerals and to measure an increase in their availability after fermentation. The antioxidants and nutritional potential of different wheat varieties was determined by DPPH (2,2-diphenyl-1-picryl- hydrazyl) and ABTS (3-ethyl-benzothiazo- line-6-sulfonic acid) radical scavenging assays as well as by the concentration of amino acids, flavonoids, minerals, carbohydrates and phenolic compounds. Different wheat varieties were showed different free radical scavenging potential after fermentation, which was significantly higher with respect to their corresponding unfermented wheat varieties. The highest nutritional and free radical scavenging potential was found in a fermented wheat variety, named Namhae, and this combination is highly useful for cereal-based food industries.

Effects of different extraction methods on contents, profiles, and antioxidant abilities of free and bound phenolics of Sargassum polycystum from the South China Sea

Total phenolic content (TPC), phenolic profiles, and antioxidant activity of free and bound extracts of Sargassum polycystum, obtained by different extraction solvents and hydrolysis methods, were investigated. Aqueous acetone afforded the highest free TPC and antioxidant ability, followed by aqueous ethanol and aqueous methanol. Twelve free phenolic compounds were identified by ultra-high-performance liquid chromatography-mass spectrometry (UHPLC-MS), including two hydroxycinnamic acids, seven flavonoids, one stilbene, and two phlorotannins. Three to nine different free phenolic compounds were extracted by these solvents with different compositions, including nine by 70% acetone and eight by 70% methanol, 70% ethanol, and 50% ethanol. The highest total content of free phenolic compounds determined by high-performance liquid chromatography-diode array detection was obtained from 70% ethanol. Alkaline hydrolysis afforded higher bound TPC (274.27 mg GAE/100 g DW) and antioxidant ability than acid hydrolysis. Five bound phenolic compounds were characterized by UHPLC-MS and five were released from alkaline hydrolysis, whereas two were released from acid hydrolysis. Total content of bound phenolic compounds released by alkaline hydrolysis was 14.68-fold higher than that by acid hydrolysis. The free and bound TPC, phenolic profiles, and antioxidant activities depended on the extraction solvent used. These results indicate that S. polycystum is a potentially useful antioxidant source and contribute to the development of seaweed-based functional foods. PRACTICAL APPLICATION: Phenolics are usually divided into free and bound forms based on their extractability and interaction with cell wall components. The nutritional effects of bound phenolics in algae have long been neglected. These topics contribute to the development of seaweed-based functional foods.

Neuroprotective potency of a soy whey fermented by Cordyceps militaris SN-18 against hydrogen peroxide-induced oxidative injury in PC12 cells

PURPOSE

Soy whey is a byproduct generated from the processing of several soybean products. Its valorization has continued to attract significant research interest in recent times due to the nutritional and bioactive potency of its chemical composition. Herein, the neuroprotective potency of a soy whey fermented by Cordyceps militaris SN-18 against hydrogen peroxide (H2O2)-induced oxidative injury in PC12 cells was investigated.

METHODS

The phenolic compositions were analyzed by high-performance liquid chromatography. Antioxidant activities were assessed by ABTS•+ scavenging assay, DPPH radical scavenging assay, reducing power assay, and ferric reducing antioxidant power assay. The neuroprotective effects of fermented soy whey (FSW) were investigated based on the oxidative injury model in PC12 cells.

RESULTS

FSW possessed higher total phenolic content and antioxidant activities compared with unfermented soy whey (UFSW) and that most of the isoflavone glycosides were hydrolyzed into their corresponding aglycones during fermentation. The extract from FSW exhibited a greater protective effect on PC12 cells against oxidative injury by promoting cell proliferation, restoring cell morphology, inhibiting lactic dehydrogenase leakage, reducing reactive oxygen species levels, and enhancing antioxidant enzyme activities compared with that from UFSW. Additionally, cell apoptosis was significantly inhibited by FSW through down-regulation of caspase-3, caspase-9, and Bax and up-regulation of Bcl-2 and Bcl-xL. S-phase cell arrest was attenuated by FSW through increasing cyclin A, CDK1 and CDK2, and decreasing p21 protein.

CONCLUSION

Fermentation with C. militaris SN-18 could significantly improve the bioactivity of soy whey by enhancing the ability of nerve cells to resist oxidative damage.

Nanoliposome-encapsulated phenolic-rich fraction from Alcea rosea as a dietary phytobiotic in mice challenged by Escherichia coli

Purpose

This research was performed to evaluate the antibacterial and health-promoting potentials of nanoliposome-encapsulated phenolic-rich fraction (PRF) from Alcea rosea leaves, as a dietary phytobiotic, in mice as challenged by enteropathogenic Escherichia coli (E. coli; O157: H7).

Method

The PEF was encapsulated in nanoliposomes (PEF-NLs), and the phenolic profiling of PEF-NLs was confirmed by HPLC. Next, 40 white male balb/c mice were assigned to four treatment groups to assess the antibacterial potential of PEF-NLs by measuring the blood parameters and the liver’s lipid peroxidation in the mice as a result of the infection caused by E. coli. Finally, the expression of cyclooxygenase 2 (COX2), inducible nitric oxide synthase (iNOS), superoxide dismutase (SOD), and glutathione peroxidase (GPx) were determined in the miceʼs ileum tissues. A real-time PCR was used to analyze the relative fold changes in the population of E. coli in the ileum.

Results

The overall results demonstrated that the nanoliposome-loaded PRF contained gallic acid, salicylic acid, pyrogallol, cinnamic acid, catechin, naringin, and ferulic acid. The E. coli intervention impaired the mice's weight gain, food intake, liver enzymes, lipid peroxidation, and the ileum’s morphometric characteristics. The challenge also upregulated the inflammatory genes (COX2, iNOS), downregulated the antioxidant-related genes (SOD and GPx), and increased the population of E. coli in the ileum. The dietary inclusion of the nonencapsulated PRF and the nanoliposome-encapsulated PRF, at the concentration of 10 mg TPC/kg BW/day, improved these parameters. However, compared to nonencapsulated PRF, the nanoliposome-encapsulated PRF appeared to be more effective in improving the health parameters in mice.

Conclusion

As a promising phytobiotic, the nanoliposome-encapsulated PRF could play a critical role against the E. coli infection in mice probably due to the increase in the higher intestinal solubility, bioavailability, and absorption of phenolic compounds encapsulated in the nanoliposome carrier.

Enzymes-Assisted Extraction of Plants for Sustainable and Functional Applications

The scientific community and industrial companies have discovered significant enzyme applications to plant material. This rise imparts to changing consumers' demands while searching for 'clean label' food products, boosting the immune system, uprising resistance to bacterial and fungal diseases, and climate change challenges. First, enzymes were used for enhancing production yield with mild and not hazardous applications. However, enzyme specificity, activity, plant origin and characteristics, ratio, and extraction conditions differ depending on the goal. As a result, researchers have gained interest in enzymes' ability to cleave specific bonds of macroelements and release bioactive compounds by enhancing value and creating novel derivatives in plant extracts. The extract is enriched with reducing sugars, phenolic content, and peptides by disrupting lignocellulose and releasing compounds from the cell wall and cytosolic. Nonetheless, depolymerizing carbohydrates and using specific enzymes form and release various saccharides lengths. The latest studies show that oligosaccharides released and formed by enzymes have a high potential to be slowly digestible starches (SDS) and possibly be labeled as prebiotics. Additionally, they excel in new technological, organoleptic, and physicochemical properties. Released novel derivatives and phenolic compounds have a significant role in human and animal health and gut-microbiota interactions, affecting many metabolic pathways. The latest studies have contributed to enzyme-modified extracts and products used for functional, fermented products development and sustainable processes: in particular, nanocellulose, nanocrystals, nanoparticles green synthesis with drug delivery, wound healing, and antimicrobial properties. Even so, enzymes' incorporation into processes has limitations and is regulated by national and international levels.

Functional implications of bound phenolic compounds and phenolics-food interaction: A review

Sizeable scientific evidence indicates the health benefits related to phenolic compounds and dietary fiber. Various phenolic compounds-rich foods or ingredients are also rich in dietary fiber, and these two health components may interrelate via noncovalent (reversible) and covalent (mostly irreversible) interactions. Notwithstanding, these interactions are responsible for the carrier effect ascribed to fiber toward the digestive system and can modulate the bioaccessibility of phenolics, thus shaping health-promoting effects in vivo. On this basis, the present review focuses on the nature, occurrence, and implications of the interactions between phenolics and food components. Covalent and noncovalent interactions are presented, their occurrence discussed, and the effect of food processing introduced. Once reaching the large intestine, fiber-bound phenolics undergo an intense transformation by the microbial community therein, encompassing reactions such as deglycosylation, dehydroxylation, α- and β-oxidation, dehydrogenation, demethylation, decarboxylation, C-ring fission, and cleavage to lower molecular weight phenolics. Comparatively less information is still available on the consequences on gut microbiota. So far, the very most of the information on the ability of bound phenolics to modulate gut microbiota relates to in vitro models and single strains in culture medium. Despite offering promising information, such models provide limited information about the effect on gut microbes, and future research is deemed in this field.

Bioactive Compounds from Pale Ale Beer Powder Attenuate Experimental Colitis in BALB/c Mice

Phenolic compounds (PCs) present in foods are associated with a decreased risk of developing inflammatory diseases. The aim of this study was to extract and characterize PCs from craft beer powder and evaluate their potential benefits in an experimental model of inflammatory bowel disease (IBD). PCs were extracted and quantified from pure beer samples. BALB/c mice received either the beer phenolic extract (BPE) or beer powder fortified with phenolic extract (BPFPE) of PCs daily for 20 days by gavage. Colon samples were collected for histopathological and immunohistochemical analyses. Dextran sodium sulfate (DSS)-induced mice lost more weight, had reduced colon length, and developed more inflammatory changes compared with DSS-induced mice treated with either BPE or BPFPE. In addition, in DSS-induced mice, the densities of CD4- and CD11b-positive cells, apoptotic rates, and activation of NF-κB and p-ERK1/2 MAPK intracellular signaling pathways were higher in those treated with BPE and BPFPE than in those not treated. Pretreatment with the phenolic extract and BPFPE remarkably attenuated DSS-induced colitis. The protective effect of PCs supports further investigation and development of therapies for human IBD.

Bound Polyphenols from Red Quinoa Prevailed over Free Polyphenols in Reducing Postprandial Blood Glucose Rises by Inhibiting α-Glucosidase Activity and Starch Digestion

Inhibiting α-glucosidase activity is important in controlling postprandial hyperglycemia and, thus, helping to manage type-2 diabetes mellitus (T2DM). In the present study, free polyphenols (FPE) and bound polyphenols (BPE) were extracted from red quinoa and their inhibitory effects on α-glucosidase and postprandial glucose, as well as related mechanisms, were investigated. HPLC-MS analysis showed that the components of FPE and BPE were different. FPE was mainly composed of hydroxybenzoic acid and its derivatives, while BPE was mainly composed of ferulic acid and its derivatives. BPE exhibited stronger DPPH and ABTS antioxidant activities, and had a lower IC50 (10.295 mg/mL) value in inhibiting α-glucosidase activity. The inhibition kinetic mode analysis revealed that FPE and BPE inhibited α-glucosidase in a non-competitive mode and an uncompetitive mode, respectively. Furthermore, compared to FPE, BPE delayed starch digestion more effectively. BPE at 50 mg/kg reduced postprandial glucose increases comparably to acarbose at 20 mg/kg in ICR mice. These results could provide perspectives on the potential of BPE from red quinoa, as a functional food, to inhibit α-glucosidase activity, delay postprandial glucose increases and manage T2DM.

Incorporation of phenolic-rich ingredients from integral valorization of Isabel grape improves the nutritional, functional and sensory characteristics of probiotic goat milk yogurt

This study elaborated different probiotic goat milk yogurt formulations with addition of a low-calorie Isabel "Precoce" grape preparation and flour from derived solid by-products. Physicochemical characteristics, probiotic counts, phenolic and protein/peptide molecular weight profile, antioxidant capacity (AC) and sensory acceptance of different yogurt formulations were evaluated. Yogurts with Isabel grape ingredients (IGI) had high nutritional value, distinct phenolic profile and high AC. High counts of probiotic Lactobacillus acidophilus La-05 were found in yogurts during storage. AC of yogurts with IGI increased during a simulated gastrointestinal digestion with breakdown of high molecular weight proteins and release of protein-bound phenolics. AC of yogurts with IGI should be linked to goat milk peptides and Isabel grape phenolics. Yogurts with IGI had enhanced sensory acceptance. Incorporation of Isabel grape preparation and derived by-product flour into probiotic goat milk yogurt resulted in an added-value product with multifunctional characteristics and improved sensory characteristics.

Hulless Black Barley as a Carrier of Probiotics and a Supplement Rich in Phenolics Targeting Against H2O2-Induced Oxidative Injuries in Human Hepatocarcinoma Cells

Lactic acid bacteria can provide benefits to human beings and transform phenolic substances to improve their potential functionality. It was of interest to develop black barley as a carrier of probiotics and nutraceutical supplement rich in more antioxidants. Due to fermentation, bacterial counting and free phenolic content in black barley increased to 9.54 ± 0.22 log cfu/mL and 5.61 ± 0.02 mg GAE/mL, respectively. Eleven phenolic compounds, including nine isoflavones and two nitrogenous compounds were characterized using UPLC-QTOF-MS, among which epicatechin, hordatine, and pelargonidin aglycone were largely enriched. Moreover, free phenolic extracts from fermented barley (F-BPE) played a greater role in scavenging DPPH radicals, reducing Fe3+ to Fe2+, and increasing oxygen radical absorbance capacity, compared phenolic extracts from unfermented barley [UF-BPE (1.94-, 1.71-, and 1.35-fold at maximum for F-BPE vs. UF-BPE, respectively)]. In hepatocarcinoma cells, F-BPE also better inhibited ROS production and improved cell viability, cell membrane integrity, SOD activity, and non-enzymatic antioxidant GSH redox status (2.85-, 3.28-, 2.05-, 6.42-, and 3.99-fold at maximum for F-BPE vs. UF-BPE, respectively).

Extraction, preparative monomer separation and antibacterial activity of total polyphenols from Perilla frutescens

Polyphenols exhibit potential functional activities, especially rosmarinic acid (RosA) and caffeic acid (CafA). In this study, two different methods, ultrasonic-assisted ethanol extraction (60%) and ultrasound-assisted cellulase (≥15 000 Ug-1, 2%) hydrolysis, were used for the extraction of the total phenolics from 44 species of Perilla frutescens. The Folin-Ciocalteu method of detection showed that the content of the total phenolics extracted by cellulase hydrolysis was the highest and attained up to 28.00 mgGAE per gextracts for ZB1. Continuously, the extracts were purified using XDA-8 macroporous resin and medium-pressure liquid chromatography (MPLC), and the content of the total phenolics improved to 66.62 mgGAE per gextract. A high-performance liquid chromatography (HPLC) assay showed that the total polyphenols were mainly composed of gallic acid, caffeic acid, rosmarinic acid, luteolin and apigenin. Besides, a sequential XDA-8 macroporous resin combined with high-speed counter-current chromatography (HSCCC)/MPLC system was established for the simultaneous isolation and preparation of RosA (purity 98.29%) and CafA (purity 97.01%) from the extracts. Furthermore, the antibacterial activities of the total polyphenols were evaluated by the disc diffusion method and scanning electron microscopy (SEM) observation. The results verified that the total polyphenols had effective antibacterial activity on three kinds of bacteria including E. coli, S. aureus, and B. subtilis in a concentration-dependent manner. All of these results demonstrated that the ultrasound-assisted cellulase hydrolysis extraction of the total polyphenols and the proposed three-step separation of RosA and CafA gave high yields and good purity, and they exhibited effective antibacterial ability.

The Progress of Nomenclature, Structure, Metabolism, and Bioactivities of Oat Novel Phytochemical: Avenanthramides

Oats are among the most commonly consumed whole grains and are widely grown worldwide, and they contain numerous nutrients, including proteins, lipids, vitamins, minerals, β-glucan, and unique phytochemical polyphenol avenanthramides (Avns). Recent studies have indicated that Avns play essential roles in mediating the health benefits of oats. This review systemically summarized the nomenclature and structures of Avns, effect of germination on promoting Avns production, and in vivo metabolites produced after Avns consumption. The classical functions and novel potential bioactivities of Avns were further elucidated. The classical functions of Avns in cancer prevention, antioxidative response, anti-inflammatory reaction, and maintaining muscle health were expounded, and the internal mechanisms of these functions were analyzed. The potential novel bioactivities of Avns in modulating gut microbiota, alleviating obesity, and preventing chronic diseases, such as atherosclerosis and osteoporosis, were further revealed. This review may provide new prospects and directions for the development and utilization of oat Avns.

Invitro bioprocessing of corn as poultry feed additive by the influence of carbohydrate hydrolyzing metagenome derived enzyme cocktail

The carbohydrate-hydrolyzing enzymes play a crucial role in increasing the phenolic content and nutritional properties of polysaccharides substrate, essential for cost-effective industrial applications. Also, improving the feed efficiency of poultry is essential to achieve significant economic benefits. The current study introduced a novel thermostable metagenome-derived xylanase named PersiXyn8 and investigated its synergistic effect with previously reported α-amylase (PersiAmy3) to enhance poultry feed utilization. The potential of the enzyme cocktail in the degradation of poultry feed was analyzed and showed 346.73 mg/g poultry feed reducing sugar after 72 h of hydrolysis. Next, the impact of solid-state fermentation on corn quality was investigated in the presence and absence of enzymes. The phenolic content increased from 36.60 mg/g GAE in control sample to 68.23 mg/g in the presence of enzymes. In addition, the enzyme-treated sample showed the highest reducing power OD 700 of 0.217 and the most potent radical scavenging activity against ABTS (40.36%) and DPPH (45.21%) radicals. Moreover, the protein and ash contents of the fermented corn increased by 4.88% and 6.46%, respectively. These results confirmed the potential of the carbohydrate-hydrolyzing enzymes cocktail as a low-cost treatment for improving the phenolic content, antioxidant activity, and nutritional values of corn for supplementation of corn-based poultry feed.

Effect of fermentation on biological functionality of cookies from fermented whole grain sorghum

Abstract This study aimed to obtain sorghum doughs subjected to two fermentation processes (backslopping and spontaneous fermentation techniques) with enhanced biological properties and to assess their influence on the bioaccessibility of phenolic compounds and Ferulic Acid (FA) of cookies formulated from fermented sorghum doughs. The best contents of Total Phenols (TP) (µgGAE/g) were 700.9 ± 7.6/36 h and 484.3 ± 6.1/48 h in sorghum doughs fermented by the backslopping and spontaneous fermentation techniques, respectively. The FA values (µg/g) in sorghum doughs fermented by backslopping techniques were significantly higher than those in spontaneous fermentation (21.2 ± 0.27/20 h versus 18.14 ± 0.12/12 h). Cookies formulated from selected sorghum-fermented doughs showed higher bioaccessibility of TP and FA than cookies formulated from nonfermented doughs. High bioaccessibility values for TP were found in cookie digests formulated from sorghum doughs fermented by backslopping and spontaneous processes at 36 h and 12 h, respectively. In contrast, high bioaccessibility values for FA were found in cookie digests formulated from sorghum doughs fermented by backslopping and spontaneous processes at 20 h and 48 h, respectively. The formulation of cookies with fermented sorghum doughs could be a suitable methodology for the prevention of several chronic nontransmissible diseases.

Traditional fermented foods and beverages in Iraq and their potential for large-scale commercialization

The tradition of making fermented foods and beverages in Iraq dates back to 7500 BC. These fermented foods and beverages are represented by meat-, milk-, vegetable-, and fruit-based products reflecting diversity of agricultural production in ancient Iraq (Mesopotamia). Although the recipes for some fermented foods and beverages were lost throughout history, those remaining foods and beverages occupy a noticeable position in modern Iraqi cuisine. In this review, knowledge and techniques for preparation of 5 traditional fermented foods, i.e. Basturma, Smoked Liban,Aushari cheese, Turshi, and Sour Khobz, and 3 fermented beverages, i.e. Shanina, Sharbet Zbeeb, and Erk Sous in Iraq, are documented. Traditional fermented foods and beverages have multiple health benefits because of high content of probiotics and bioactive compounds. Traditional fermented foods and beverages are made using the back-slopping technique which ensures safety of production and maintains organoleptic properties. The review highlights the potential of fermented foods and beverages for their large-scale commercialization.

Phytochemical profile, bioactivity and prebiotic potential of bound polyphenols released from Rosa Roxburghii fruit pomace dietary fiber during in vitro digestion and fermentation

The aim of this study was to elucidate liberation and phytochemical profile of bound polyphenols existed in dietary fiber (RPDF) isolated from Rosa roxburghii fruit pomace during in vitro simulated...

Impact of solid-state fermentation on factors and mechanisms influencing the bioactive compounds of grains and processing by-products

Cereal and legume grains and their processing by-products are rich sources of bioactives such as phenolics with considerable health potential, but these bioactives suffer from low bioaccessibility and bioavailability, resulting in limited use. Several studies have demonstrated that solid-state fermentation (SSF) with food-grade microorganisms is effective in releasing bound phenolic compounds in cereal and legume products. In this review, we discuss the effect of SSF on cereal and legume grains and their by-products by examining the role of specific microorganisms, their hydrolytic enzymes, fermentability of agri-food substrates, and the potential health benefits of SSF-enhanced bioactive compounds. SSF with fungi (Aspergillus spp. and Rhizopus spp.), bacteria (Bacillus subtilis and lactic acid bacteria (LAB) spp.) and yeast (Saccharomyces cerevisiae) significantly increased the bioactive phenolics and antioxidant capacities in cereal and legume grains and by-products, mainly through carbohydrate-cleaving enzymes. Increased bioactive phenolic and peptide contents of SSF-bioprocessed cereal and legume grains have been implicated for improved antioxidant, anti-inflammatory, anti-carcinogenic, anti-diabetic, and angiotensin-converting-enzyme (ACE) inhibitory effects in fermented agri-food products, but these remain as preliminary results. Future research should focus on the microbial mechanisms, suitability of substrates, and the physiological health benefits of SSF-treated grains and by-products.

Preparation and characterization of a dihydromyricetin-sugar beet pectin covalent polymer

A dihydromyricetin (DMY)-sugar beet pectin (SBP) covalent polymer was prepared using an alkaline method for the first time, and its structure and physicochemical properties were characterized. The results showed that the molecular weight, total phenol content, and ABTS radical scavenging ability of the polymer were positively correlated with DMY dosage. The polymer inhibited α-glucosidase in a mixed non-competitive and anti-competitive inhibition manner, and its inhibition performance depended on the total phenol content. Its maximum inhibitory activity was much higher than that of DMY, which was attributed to its strong protein binding capacity. The stability and β-carotene protective effects of the nano-emulsions stabilized with the DMY-SBP polymers were also positively correlated to the total phenol content and were superior to those stabilized by SBP. Therefore, the results obtained in this study may improve our functional understanding of natural polyphenol-polysaccharide polymers and promote the development of new nutraceuticals.

Effect of soaking and germination treatments on nutritional, anti-nutritional, and bioactive properties of amaranth (Amaranthus hypochondriacus L.), quinoa (Chenopodium quinoa L.), and buckwheat (Fagopyrum esculentum L.)

Pseudocereals have attracted the attention of nutritionists and food technologists due to their high nutritional value. In addition to their richness in nutritional and bioactive components, these are deficient in gluten and can serve as valuable food for persons suffering from gluten allergies. Processing treatments are considered an effective way to enhance the quality of food grains. Soaking and germination are traditional and most effective treatments for enhancing the nutritional and bioactive potential as well as reducing the anti-nutritional components in food grains. This study reflects the effect of soaking and germination treatments on nutritional, bioactive, and anti-nutritional characteristics of pseudocereals. There was a significant (p ≤ 0.05) increase in nutritional and bioactive components such as crude fiber, crude protein, phenolic components, antioxidant activity, and mineral content but reduced the anti-nutrients such as tannin and phytic acid. In amaranth, there was a significant increase (p ≤ 0.05) of 7.01, 74.67, 126.62, and 87.47% in crude protein, crude fiber, phenolic content, and antioxidant activity but significant (p ≤ 0.05) reduction of 32.30% and 29.57% in tannin and phytic acid contents, respectively. Similar changes in values of crude proteins, crude fiber, phenolic content, and antioxidant activity were observed in buckwheat and quinoa. While the anti-nutritional components such as tannin and phytic acid decreased by 59.91 and 17.42%, in buckwheat and 27.08% and 47.57%, in quinoa, respectively. Therefore, soaking and germination proved to be excellent techniques to minimize the anti-nutritional component and enhance the nutritional, bioactive, and antioxidant potential of these underutilized grains.

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Pseudocereals were found to be a rich source of nutritional and bioactive components.

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Processing treatments (soaking and germination) were found effective in improving the nutritional as well as bioactive components.

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The anti-nutrients such as tannin and phytic acid contents decreased significantly thereby enhancing the nutritional potential of these underutilized grains.