Phenolic composition and antioxidant activity of colored oats

Regulation of the phenolic release and conversion in oats (Avena sativa L.) by co-microbiological fermentation with Monascus anka, Saccharomyces cerevisiae and Bacillus subtilis

Microbial fermentation is an effective method to improve the functional activity of oats (Avena sativa L.), while there are some limitations to the advantages of single microbial fermentation. In this study, a microbial co-culture fermentation system with Monascus anka, Saccharomyces cerevisiae and Bacillus subtilis to release and conversion oat phenolics was established. Results showed that the optimal microbial co-fermentation system was obtained by adding Saccharomyces cerevisiae on the fourth day and Bacillus subtilis on the eighth day during Monascus anka fermentation (MF + 4S + 8B). The phenolic content was reached 26.93 mg GAE/g DW, which increased 41.08 times compared to un-fermented oats (UF). In the process of co-fermentation systems, cellulase and β-glucosidase (r2 = 0.97, p < 0.01) had a positive correlation with the release of phenolics. SEM combined with HPLC showed that the complex enzyme system produced by microbial co-fermentation enhanced the disruption of oat cell structure, as well as altered the phenolics fractions and facilitated the conversion of bound phenolics to free phenolics, especially the content of chlorogenic acid and vanillic acid in the free forms was increased 31.42 and 14.15 times, respectively. Additionally, the phenolic contents were increased and the components were changed with the microbial co-fermentation of crude enzyme solution further added, which validated the positive influence of complex enzyme system of MF + 4S + 8B in the phenolic release and transformation of oats. Therefore, this study systematically investigated the phenolic mobilization in oats during the co-fermentation period, which provides a viable option for improving the functional properties of cereal products, as well as the application of microbial cell factories.

Characterization and Potential Food Applications of Oat Flour and Husks from Differently Colored Genotypes as Novel Nutritional Sources of Bioactive Compounds

Oats are gluten-free cereals rich in dietary fiber, β-glucans, phenolic acids, flavonoids, carotenoids, vitamin E, and phytosterols. They have been used in traditional medicine for centuries to treat hyperacidity, acute pancreatitis, burns, and skin inflammation. This study assessed the nutritional and phenolic profile of oat flour (OF) and ground oat husks (OHs) from white, brown, and black hulled oat genotypes, as well as the antioxidant and antimicrobial activity of their extracts. The extracts were tested on six strains of gastrointestinal tract pathogens. OF samples had, on average, a high protein content (15.83%), fat content (6.27%), and β-glucan content (4.69%), while OH samples were rich in dietary fiber. OHs had significantly higher average total phenolic compounds compared to OF and had twice as high antioxidant capacity. Ferulic acid was predominant in all samples, followed by p-coumaric, isoferulic, vanillic, and syringic acid. The traditionally prepared OH extracts manifested the best bactericidal activity against Listeria monocytogenes, Escherichia coli, and Staphylococcus haemolyticus, while Salmonella typhimurium was the least sensitive to the bactericidal effect of all the investigated samples. Both OF and powdered OHs have potential applications in the functional food industry and pharmacy due to their bioactive compounds, their biological activity, as well as their overall nutritional profile.

Studies on the Enzymatic Synthesis and Antioxidant Properties of Phenolic Acid Glycerols

The potentially wide application of Phenolic acids (PAs) in industries was severely limited by their inadequate solubility and stability in polar/non-polar media. To overcome these limits, studies on the enzymatic esterification of PAs with glycerol were carried out to reach a yield of 95% of phenolic acid glycerols (PAGs) under the following reaction conditions: 1:150 molar ratio of PAs to glycerol; 25% of Lipozyme 435 relative to the weight of total substrates; 80°C, 500 rpm, 86.7 kPa and 10 h. Three resulting PAGs including caffeoyl glycerol (CG), feruloyl glycerol (FG), and p-hydroxycinnamoyl glycerol (p-HCG) were confirmed by MS, 1H NMR and 13C NMR. Among them, CG showed a comparative free radical scavenging ability to CA, indicating its potential use as a water-soluble antioxidant alternative to CA for food and cosmetic applications.

In vitro digestion and fermentation characteristics of soluble dietary fiber from adlay (Coix lacryma-jobi L. var. ma-yuen Staft) bran modified by steam explosion

Adlay bran is known for its nutrient-rich profile and multifunctional properties, and steam explosion (SE) is an emerging physical modification technique. However, the specific effects of SE on the activity composition and antioxidant capacity of adlay bran soluble dietary fiber (SDF) during in vitro digestion, as well as its influence on gut microbiota during in vitro fermentation, remain inadequately understood. This paper reports the in vitro digestion and fermentation characteristics of soluble dietary fiber from adlay bran modified by SE (SE-SDF). Compared with the untreated samples (0-SDF), most of the phenolic compounds and antioxidant capacity were significantly increased in the SE-SDF digests. Additionally, SE was beneficial for adlay bran SDF to increase the content of acetic acid, propionic acid and total short-chain fatty acids (SCFAs) in fermentation broth during in vitro fermentation. SE-SDF could promote the growth of beneficial bacteria while inhibiting the proliferation of pathogenic microbes. Our research indicates that SE-SDF shows strong antioxidant properties after in vitro digestion and plays a pivotal role in regulating gut microbiota during in vitro fermentation, ultimately enhancing human intestinal health.

Nutritional Traits, Pasting Properties and Antioxidant Profile of Selected Genotypes of Sorghum, Oat and Maize Eligible for Gluten-Free Products

The technological and nutritional traits of food-grade sorghum hybrids, hulled/naked oat varieties and maize genotypes of different colors were studied for novel and healthier gluten-free foods. Oat genotypes showed the highest protein content, followed by maize and sorghum. The total starch and the total dietary fiber content were quite similar among the three species. Great variation was found in the amylose content, and the highest was in sorghum (27.12%), followed by oat 16.71% and maize 10.59%. Regarding the pasting profile, the rank of Peak Viscosity was sorghum (742.8 Brabender Unit, BU), followed by maize (729.3 BU) and oat (685.9 BU). Oat and sorghum genotypes had similar average breakdown (407.7 and 419.9 BU, respectively) and setback (690.7 and 682.1 BU, respectively), whereas maize showed lower values for both parameters (384.1 BU and 616.2 BU, respectively). The total antioxidant capacity, only in maize, significantly correlated with total flavonoid, phenolic and proanthocyanidin contents, indicating that all the measured compounds contributed to antioxidant capacity. The study indicated the importance of sounding out the nutritional and technological characteristics of gluten-free cereals in order to select suitable cultivars to be processed in different gluten-free foods with better and healthier quality.

Combined Strategy Using High Hydrostatic Pressure, Temperature and Enzymatic Hydrolysis for Development of Fibre-Rich Ingredients from Oat and Wheat By-Products

Wheat bran (WB) and oat hull (OH) are two interesting undervalued cereal processing sources rich in total dietary fibre (TDF) and other associated bioactive compounds, such as β-glucans and polyphenols. The aim of this study was to optimise a combination chemical (enzymes) and physical (high hydrostatic pressure-temperature) strategies to increase the bioaccessibility of bioactive compounds naturally bound to the bran and hull outer layers. WB and OH were hydrolysed using food-grade enzymes (UltraFloXL and Viscoferm, for WB and OH, respectively) in combination with HPP at different temperatures (40, 50, 60 and 70 °C) and hydrolysis either before or after HPP. Proximal composition, phytic acid, β-glucans, total phenolics (TPs) and total antioxidant activity (TAC) were evaluated to select the processing conditions for optimal nutritional and bioactive properties of the final ingredients. The application of the hydrolysis step after the HPP treatment resulted in lower phytic acid levels in both matrices (WB and OH). On the other hand, the release of β-glucan was more effective at the highest temperature (70 °C) used during pressurisation. After the treatment, the TP content ranged from 756.47 to 1395.27 µmol GAE 100 g-1 in WB, and OH showed values from 566.91 to 930.45 µmol GAE 100 g-1. An interaction effect between the temperature and hydrolysis timing (applied before or after HPP) was observed in the case of OH. Hydrolysis applied before HPP was more efficient in releasing OH TPs at lower HPP temperatures (40-50 °C); meanwhile, at higher HPP temperatures (60-70 °C), hydrolysis yielded higher TP values when applied after HPP. This effect was not observed in WB, where the hydrolysis was more effective before HPP. The TP results were significantly correlated with the TAC values. The results showed that the application of optimal process conditions (hydrolysis before HPP at 60 or 70 °C for WB; hydrolysis after HPP at 70 °C for OH) can increase the biological value of the final ingredients obtained.

Oat Peptides Alleviate Dextran Sulfate Sodium Salt-Induced Colitis by Maintaining the Intestinal Barrier and Modulating the Keap1-Nrf2 Axis

The prevalence of inflammatory bowel disease (IBD) is progressively rising each year, emphasizing the significance of implementing rational dietary interventions for disease prevention. Oats, being a staple agricultural product, are abundant in protein content. This study aimed to investigate the protective effects and underlying mechanisms of oat peptides (OPs) in a mouse model of acute colitis induced by dextran sulfate sodium salt (DSS) and a Caco-2 cell model. The findings demonstrated that intervention with OPs effectively mitigated the symptoms associated with DSS-induced colitis. The physicochemical characterization analysis demonstrated that the molecular weight of the OPs was predominantly below 5 kDa, with a predominant composition of 266 peptides. This study provides further evidence of the regulatory impact of OPs on the Keap1-Nrf2 signaling axis and elucidates the potential role of WGVGVRAERDA as the primary bioactive peptide responsible for the functional effects of OPs. Ultimately, the results of this investigation demonstrate that OPs effectively mitigate DSS-induced colitis by preserving the integrity of the intestinal barrier and modulating the Keap1-Nrf2 axis. Consequently, these findings establish a theoretical foundation for the utilization of OPs as dietary supplements to prevent the onset of IBD.

Characterization of isogenic mutants with single or double deletions of four phenolic acid esterases in Lactiplantibacillus plantarum TMW1.460

In plants, hydroxycinnamic and hydroxybenzoic acids occur mainly as esters. This study aimed to determine the contribution of individual phenolic acid esterases in Lp. plantarum TMW1.460, which encodes for four esterases: TanA, Lp_0796, Est_1092 and a homolog of Lj0536 and Lj1228 that was termed HceP. To determine which of the phenolic acid esterases present in Lp plantarum TMW1.460 are responsible for esterase activity, mutants with deletions in lp_0796, est_1092, tanB, hceP, or hceP and est_1092 were constructed. The phenotype of wild type strain and mutants was determined with esters of hydroxycinnamic acids (chlorogenic acid and ethyl ferulate) and of hydroxybenzoic acids (methyl gallate, tannic acid and epigallocatechin-3-gallate). Lp. plantarum TMW1.460 hydrolysed chlorogenic acid, methyl ferulate and methyl gallate but not tannic acid or epigallocatechin gallate. The phenotype of mutant strains during growth in mMRS differed from the wild type as follows: Lp. plantarum TMW1.460ΔhceP did not hydrolyse esters of hydroxycinnamic acids; Lp. plantarum TMW1.460ΔtanB did not hydrolyse esters of hydroxybenzoic acids; disruption of est_1092 or Lp_0796 did not alter the phenotype. The phenotype of Lp. plantarum TMW1.460ΔΔhceP/est_1092 was identical to Lp. plantarum TMW1.460ΔhceP. The metabolism of phenolic acids during growth of the mutant strains in broccoli puree and wheat sourdough did not differ from metabolism of the wild type strain. In conclusion, esters of hydroxycinnamic and hydroxybenzoic acids each are hydrolysed by dedicated enzymes. The hydroxycinnamic acid esterase HceP is not expressed, or not active during growth of Lp. plantarum TMW1.460 in all food substrates.

Impact of Oats on Appetite Hormones and Body Weight Management: A Review

PURPOSE OF REVIEW

This study aims to review the hunger hormones in obesity management and the impact of oats in regulating these hormones for hunger suppression and body weight management. In this review, the impact of various edible forms of oats like whole, naked, sprouted, or supplemented has been investigated for their appetite hormones regulation and weight management.

RECENT FINDINGS

The onset of obesity has been greatly associated with the appetite-regulating hormones that control, regulate, and suppress hunger, satiety, or energy expenditure. Many observational and clinical studies prove that oats have a positive effect on anthropometric measures like BMI, waist circumference, waist-to-hip ratio, lipid profile, total cholesterol, weight, appetite, and blood pressure. Many studies support the concept that oats are rich in protein, fiber, healthy fats, Fe, Zn, Mg, Mn, free phenolics, ß-glucan, ferulic acid, avenanthramides, and many more. Beta-glucan is the most important bioactive component that lowers cholesterol levels and supports the defense system of the body to prevent infections. Hence, several clinical studies supported oats utilization against obesity, appetite hormones, and energy regulation but still, some studies have shown no or little significance on appetite. Results of various studies revealed the therapeutic potentials of oats for body weight management, appetite control, strengthening the immune system, lowering serum cholesterol, and gut microbiota promotion by increased production of short-chain fatty acids.

Conversion of (poly)phenolic compounds in food fermentations by lactic acid bacteria: Novel insights into metabolic pathways and functional metabolites

Lactobacillaceae are among the major fermentation organisms in most food fermentations but the metabolic pathways for conversion of (poly)phenolic compounds by lactobacilli have been elucidated only in the past two decades. Hydroxycinnamic and hydroxybenzoic acids are metabolized by separate enzymes which include multiple esterases, decarboxylases and hydroxycinnamic acid reductases. Glycosides of phenolic compounds including flavonoids are metabolized by glycosidases, some of which are dedicated to glycosides of plant phytochemicals rather than oligosaccharides. Metabolism of phenolic compounds in food fermentations often differs from metabolism in vitro, likely reflecting the diversity of phenolic compounds and the unknown stimuli that induce expression of metabolic genes. Current knowledge will facilitate fermentation strategies to achieve improved food quality by targeted conversion of phenolic compounds.

Sprouting and Hydrolysis as Biotechnological Tools for Development of Nutraceutical Ingredients from Oat Grain and Hull

Oat consumption has increased during the last decade because of the health benefits associated with its soluble dietary fiber (β-glucan), functional proteins, lipids, and the presence of specific phytochemicals, such as avenanthramides. Oat is consumed mainly as whole grain, and the hull (seed coat), comprising 25–35% of the entire grain, is removed, generating a large amount of waste/by-product from the milling industry. The objective of this study was to evaluate the use of biotechnological strategies, such as sprouting for oat grain (OG) and hydrolysis for oat hull (OH), to enhance antioxidant and anti-inflammatory properties and lower the glycemic index (GI). Sprouting produced significant (p ≤ 0.05) increases in free (32.10 to 76.62 mg GAE (100 g)−1) and bound phenols (60.45 to 124.36 mg GAE (100 g)−1), increasing significantly (p ≤ 0.05) the avenanthramide (2c, 2p and 2f) soluble phenolic alkaloid content and anti-inflammatory properties of OG. On the other hand, the hydrolysis of OH using Viscoferm (EH2-OH) and Ultraflo XL (EH21-OH) increased by 4.5 and 5-fold the release of bound phenols, respectively; meanwhile, the use of Viscoferm increased the 4.55-fold soluble β-glucan content in OH, reaching values close to those of OG (4.04 vs. 4.46 g (100 g)−1). The study shows the potential of both strategies to enhance the nutritional and bioactive properties of OG and OH and describes these processes as feasible for the industry to obtain an ingredient with high antioxidant and anti-inflammatory activities. Single or combined biotechnological tools can be used on oat grains and hulls to provide nutraceutical ingredients.

Micronized Oat Husk: Particle Size Distribution, Phenolic Acid Profile and Antioxidant Properties

Oat husk (OH; hull) is a by-product generated from oat processing and is rich in insoluble fibre and phenolic compounds. The aim of this work was to study the particle size distribution, antioxidant activity, and phenolic profile of micronized OH. For this purpose, the hull was first sterilized using superheated steam and was then ground using an impact classifier mill. The particle size distribution (PSD) of the ground husk was determined using the laser diffraction method and the parameters characterizing the PSD of the ground husk, and its antioxidant activity were calculated. In addition, UPLC-MS/MS analysis of phenolic acids was also performed. Micronization of the sterilized husk effectively decreased the size of the particles, and with the increasing speed of the rotor and classifier, the median size of the particles (d50) decreased from 63.8 to 16.7 µm. The following phenolic acids were identified in OH: ferulic, caffeic, p-hydroxybenzoic, vanillic, syringic, and synapic acid. Ferulic acid constituted about 95% of total phenolic acids. The antioxidant activity of the obtained extracts increased as the particle size of the micronized husk decreased. The highest half maximal inhibitory concentration (EC50 index) was found for chelating power, and the lowest was found in the case of radical scavenging activity against DPPH.

Chemical and biochemical bleaching of oat hulls: The effect of hydrogen peroxide, laccase, xylanase and sonication on optical properties and chemical composition

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Alkaline hydrogen peroxide is a mild and robust bleaching method for oat hulls.

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The lignocellulose content is not altered during alkaline H₂O₂ bleaching.

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Neither phenolic acids nor coniferaldehyde structures are removed during bleaching.

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Laccase, xylanase and sonication are not suitable for biobleaching of oat hulls.

Oat hulls are an excellent dietary fibre source for food supplements due to their rich lignocellulose composition as well as their great abundance as low-value agricultural side stream. For the production of white fibre supplements, a mild, but effective bleaching of the hulls is required. Chemical bleaching with hydrogen peroxide and sodium hydroxide was here found to be a suitable method increasing the CIE L* value (corresponds to a lightness value) above 85. The developed method is mild, retaining the hull’s chemical composition. Only a minor decrease in coniferaldehyde structures upon bleaching was detected. Colour and chemical variabilities of oat hulls from different growth seasons did not influence the required bleaching conditions to achieve the desired optical properties. The inclusion of biochemical bleaching steps utilizing the xylanase Pentopan Mono BG, the laccase NS51003 and sonication was industrially not feasible as they could not reduce the required amount of subsequently applied bleaching chemicals significantly.

Polyphenols and avenanthramides extracted from oat (Avena sativa L.) grains and sprouts modulate genes involved in glucose and lipid metabolisms in 3T3 L1 adipocytes

This study aimed to evaluate the effect of polyphenol (PE) and avenanthramide (AE) extracts from oat grains (OG) and sprouts (OS) on genes related to glucose and lipid metabolisms in 3T3 L1 adipocytes. The AE-OS exerted the greatest effect on genes involved in glucose metabolism, increasing Glut4, Irs1, and Pi3k expression by 3.0- to 3.9-fold. Conversely, the PE-OS exerted the greatest effect on genes involved in lipid metabolism, decreasing Fasn and Acaca expression by 0.2- to 0.3-fold, and increasing Cpt1a and Acadm expression by 2.7- to 3.0-fold. These effects were mainly related to their high content of avenanthramides A (2p), B (2f), and C (2c), quercetin 3-O-rutinoside, kaempferol, sinapoylquinic acid, and apigenin and luteolin derivatives according to the chemometric analysis. In conclusion, this study demonstrated that oat sprouts extract exerts a greater effect than oat grains on the regulation of genes involved in glucose and lipid metabolisms in adipocytes. PRACTICAL APPLICATIONS: This study demonstrates that polyphenols and avenanthramides extracted from oat (Avena sativa L.) grains and sprouts modulate key genes involved in glucose and lipid metabolisms in adipocytes and that oat sprouts exert a greatest health beneficial effect than oat grains due to their higher content of bioactive compounds. In addition, the chemometric analysis identified the bioactive compounds that can be associated with the beneficial effects of oat grains and sprouts, which can be further used for the identification of oat varieties and oat-derived products with high content of these bioactive compounds and, thus, with high nutraceutical potential.

In Vitro Assessment of Enteric Methane Emission Potential of Whole-Plant Barley, Oat, Triticale and Wheat

The study determined in vitro enteric methane (CH₄) emission potential of whole-plant cereal (WPC) forages in relationship to nutrient composition, degradability, and rumen fermentation. Two varieties of each WPC (barley, oat, triticale, and wheat) were harvested from two field replications in each of two locations in central Alberta, Canada, and an in vitro batch culture technique was used to characterize gas production (GP), fermentation, and degradability. Starch concentration (g/kg dry matter (DM)) was least (p < 0.001) for oat (147), greatest for wheat (274) and barley (229), and intermediate for triticale (194). The aNDF concentration was greater for oat versus the other cereals (531 vs. 421 g/kg DM, p < 0.01). The 48 h DM and aNDF degradabilities (DMD and aNDFD) differed (p < 0.001) among the WPCs. The DMD was greatest for barley, intermediate for wheat and triticale, and least for oat (719, 677, 663, and 566 g/kg DM, respectively). Cumulative CH₄ production (MP; mL) from 12 h to 48 h of incubation was less (p < 0.001) for oat than the other cereals, reflecting its lower DMD. However, CH₄ yield (MY; mg of CH₄/g DM degraded) of barley and oat grown at one location was less than that of wheat and triticale (28 vs. 31 mg CH₄/g DM degraded). Chemical composition failed to explain variation in MY (p = 0.35), but it explained 45% of the variation in MP (p = 0.02). Variation in the CH₄ emission potential of WPC was attributed to differences in DMD, aNDFD, and fermentation end-products (R² ≥ 0.88; p < 001). The results indicate that feeding whole-plant oat forage to ruminants may decrease CH₄ emissions, but animal performance may also be negatively affected due to lower degradability, whereas barley forage may ameliorate emissions without negative effects on animal performance.

Release of characteristic phenolics of quinoa based on extrusion technique

Quinoa is rich in phenolics which are benefit for human health for their outstanding antioxidant capacity, anti-inflammatory property and special biological functions. However, most of phenolics existed as bound form that with low bioavailability in quinoa. In this study, extrusion technique was applied for the release of bound phenolics in red quinoa (RQ), and effects of extruded temperature (120 °C, 140 °C, 160 °C and 180 °C) on the release of characteristic phenolics of RQ was investigated as well. Phenolics both presented as free and bound forms were identified in RQ and extruded quinoa samples, and result showed rutin, ferulic acid and vanillic acid were most common. The content of bound phenolics in RQ was 155.52 mg/kg, however, in extruded red quinoa (ERQ) was 77.25 mg/kg (ERQ-140 °C)-84.08 mg/kg (ERQ-120 °C). In corresponding, free phenolics in RQ was 22.15 mg/kg, while in ERQ was 41.04 mg/kg (ERQ-140 °C)-47.25 mg/kg (ERQ-160 °C). In conclusion, extrusion was excellent for the release of bound phenolics in quinoas and the best extruded temperature was 160 °C. Extrusion technique was potential in the processing of quinoa.

Warming weather changes the chemical composition of oat hulls

The current threats of climate change are driving attention away from the petrochemical industry towards more sustainable and bio-based production processes for fuels and speciality chemicals. These processes require suitable low-cost starting material. One potential material assessed here is the oat hull. Its overall chemical composition has so far not been fully characterized. Furthermore, it is not known how it is affected by extreme weather events. Oat hulls (Kerstin and Galant varieties) grown during 'normal' weather years (2016 and 2017) are compared to the harvest of the warmer and drier year (2018). Standard methods for determination of plant chemical composition, with focus on carbohydrate composition, are utilized. Oat hulls grown in 'normal' weather conditions (2017) are rich in lignocellulose (84%), consisting of 35% hemicellulose, 25% lignin and 23% cellulose. Arabinoxylan was found to be the major biopolymer (32%). However, this composition is greatly influenced by weather variations during the oat growth phase. A lignocellulose reduction of 25% was recorded in the warmer and drier 2018 harvest. Additionally, a 6.6-fold increase in starch content, a four-fold increase in protein content and a 60% decrease in phenolic content was noted. Due to its high lignocellulose composition, with an exceptionally large hemicellulose fraction, the chemical composition of oat hulls is unique among agricultural by-products. However, this characteristic is significantly reduced when grown in warmer and drier weather, which could compromise its suitability for use in a successful biorefinery.

A systematic review of phytochemicals in oat and buckwheat

Consumption of oat and buckwheat have been associated with various health benefits that may be attributed to their nutritional composition. We performed a systematic review to evaluate the profile and quantity of bioactive compounds present in oat and buckwheat. Among 154 studies included in final analysis, 113 and 178 bioactive compounds were reported in oat and buckwheat, respectively. Total phytosterols, tocols, flavonoids and rutin content were generally higher in buckwheat, β-glucans were significantly higher in oat, while avenanthramides and saponins were characteristically present in oat. The majority of studies included in current review were published before 2010s. The heterogeneous methodological procedures used across the studies precluded our possibility to meta-analyse the evidence and raises the need for harmonization of separation and extraction methods in future studies. Our findings should further stimulate the exploration of metabolites related to identified phytochemicals and their roles in human health.

Green synthesis of CuO- and Cu2O-NPs in assistance with high-gravity: The flowering of nanobiotechnology

This study, for the first time, reports the synthesis of CuO- and Cu2O nanoparticles (NPs) using the Salvia hispanica extract by a high-gravity technique. The original green synthesis procedure led to the formation of nanoparticles with promising catalytic and biological properties. The synthesized nanoparticles were fully characterized and their catalytic activity was evaluated through a typical Azide-Alkyne Cycloaddition (AAC) reaction. The potential antibacterial activity against gram positive (S. aureus) and gram negative (E. coli) bacteria were investigated. It was shown that the antibacterial properties were independent of the NP morphology as well as of the texture of the synthesis media. As a result, the presently synthesized nanoparticles showed very good photocatalytic and catalytic activities in comparison with the literature. From a biological perspective, they showed lower cytotoxicity in comparison with the literature, and also showed higher antioxidant and antibacterial activities. Thus, these present green CuO and Cu2O nanoparticles deserve further attention to improve numerous medical applications.

Comprehensive analysis of oat avenanthramides using hybrid quadrupole-Orbitrap mass spectrometry: Possible detection of new compounds

RATIONALE

Avenanthramides (AVNs) are constituents unique to oats and have many outstanding health benefits. AVNs are antioxidants and possess anti-inflammatory, antifungal and antibacterial activity. The number of known AVNs increased recently because of the latest developments in high-resolution tandem mass spectrometry (HRMS/MS) techniques.

METHODS

Oat seed extract from 10 oat cultivars was analysed using ultra-high-performance liquid chromatography (UHPLC) and Q Exactive hybrid quadrupole-Orbitrap mass spectrometry (HRMS/MS) with positive heated electrospray ionization.

RESULTS

Thirty-five AVNs were identified and characterized in seed extracts, and the structures of 10 novel AVNs were tentatively elucidated, among which were AVNs bearing a cinamoyl or sinapoyl moiety. These AVNs are reported in oats for the first time. The method was validated using AVN standards (AVNs 2c, 2f and 2p), with limits of detection and quantitation at low picomole levels. Recovery of AVN standards varied from 83% to 106%, and relative standard deviations ranged from 2% to 9%. The total AVNs in the selected oat varieties ranged from 36.0 to 302.5 μg/g (dry weight), with AVN 2c, AVN 2f and AVN 2p representing approximately 65%-70% of that total.

CONCLUSIONS

Our comprehensive method for detecting the full avenanthramide spectrum can contribute to better understanding the chemical and biological properties of individual AVNs for utilization in developing new oat cultivars and novel functional foods.

Anti-Inflammatory and Cytotoxic Potential of New Phenanthrenoids from Luzula Sylvatica

Phenanthrenoids have been widely described, in the Juncaceae family, for theirbiological properties such as antitumor, anxiolytic, anti-microbial, spasmolytic, and antiinflammatoryactivities. The Juncaceae family is known to contain a large variety ofphenanthrenoids possessing especially anti-inflammatory and cytotoxic properties. Luzulasylvatica, a Juncaceae species, is widely present in the Auvergne region of France, but has neverbeen studied neither for its phytochemical profile nor for its biological properties. We investigatedthe phytochemical profile and evaluated the potential anti-inflammatory activities of L. sylvaticaaerial parts extracts. A bioassay-guided fractionation was carried out to identify the most activefractions. Nine compounds were isolated, one coumarin 1 and eight phenanthrene derivatives (2-9), including four new compounds (4, 5, 8 and 9), from n-hexane and CH2Cl2, fractions. Theirstructures were established by HRESIMS, 1D and 2D NMR experiments. The biological properties,especially the anti-inflammatory/antioxidant activities (ROS production) and antiproliferativeactivity on THP-1, a monocytic leukemia cell line, of each compound, were evaluated. Threephenanthrene derivatives 4, 6, and 7 showed very promising antiproliferative activities.Phenanthrene derivatives.

Natural Products, Traditional Uses and Pharmacological Activities of the Genus Biebersteinia (Biebersteiniaceae)

Medicinal plants have been known as a rich source of natural products (NPs). Due to their diverse chemical structures and remarkable pharmacological activities, NPs are regarded as important repertoires for drug discovery and development. Biebersteinia plant species belong to the Biebersteiniaceae family, and have been used in folk medicines in China and Iran for ages. However, the chemical properties, bioactivities and modes of action of the NPs produced by medicinal Biebersteinia species are poorly understood despite the fact that there are only four known Biebersteinia species worldwide. Here, we reviewed the chemical classifications and diversity of the various NPs found in the four known Biebersteinia species. We found that the major chemical categories in these plants include flavonoids, alkaloids, phenylpropanoids, terpenoids, essential oils and fatty acids. We also discussed the anti-inflammatory, analgesic, antibacterial, antioxidant, antihypertensive and hypoglycemic effects of the four Biebersteinia species. We believe that the present review will facilitate the exploration of traditional uses and pharmacological properties of Biebersteinia species, extraction of the NPs and elucidation of their molecular mechanisms, as well as the development of novel drugs based on the reported properties and mode-of-action.

In vitro digestion effect on mineral bioaccessibility and antioxidant bioactive compounds of plant-based beverages

Consumption of plant-based beverages (PBB) is a growing trend; and have been used as viable substitutes for dairy based products. To date, no study has comparatively analyzed mineral composition and effect of in vitro digestion on the bioaccessibility of different PBB. The aim of this research was to investigate the content of essential minerals (calcium (Ca), magnesium (Mg), iron (Fe), zinc (Zn)) and to estimate the effect of in vitro digestion in plant-based beverages, and their antioxidant bioactive compounds (phenolic compounds and antioxidant capacity). Moreover, the presence of antinutritional factors, such as myo-inositol phosphates fractions, were evaluated. Samples of PBB (rice, cashew nut, almond, peanut, coconut, oat, soy, blended or not with another ingredients, fortified with minerals or naturally present) and milk for comparison were evaluated. TPC ranged from 0.2 mg GAEq/L for coconut to 12.4 mg GAEq/L for rice and, the antioxidant capacity (DPPH) ranged from 3.1 to 306.5 µmol TE/L for samples containing peanut and oat, respectively. Only a few samples presented myo-inositol phosphates fractions in their composition, mostly IP5 and IP6, especially cashew nut beverages. Mineral content showed a wide range for Ca, ranging from 10 to 1697.33 mg/L for rice and coconut, respectively. The Mg content ranged from 6.29 to 251.23-268.43 mg/L for rice and cashew nut beverages, respectively. Fe content ranged from 0.76 mg/L to 12.89 mg/L for the samples of rice. Zinc content ranged from 0.57 mg/L to 8.13 mg/L for samples of oat and soy, respectively. Significant variation was observed for Ca (8.2-306.6 mg/L) and Mg (1.9-107.4 mg/L) dialyzed between the beverages, with lower concentrations of Fe (1.0 mg/L) and Zn (0.5 mg/L) in dialyzed fractions. This study provides at least 975 analytically determined laboratory results, providing important information for characterization and comparison of different plant-based beverages.

Enhancement of Antioxidant Activity in O/W Emulsion and Cholesterol-Reducing Capacity of Epigallocatechin by Derivatization with Representative Phytosterols

In this study, derivatization of epigallocatechin (EGC) by representative phytosterols (stigmasterol and β-sitosterol) was performed employing Steglich esterification. The structural identity and purity of epigallocatechin β-sitosterol (ESi) and epigallocatechin stigmasterol (ESt) were confirmed by NMR, FT-IR, and HPLC-MS. Further evaluation of ESi and ESt revealed their extraordinary antioxidant activities in O/W emulsion. Two different radical sources in oil or aqueous phase were applied to explore the antioxidant behavior in O/W emulsion. The mechanism was further investigated by fluorescent microscopy and transmission electron microscopy (TEM). Furthermore, incorporation of EGC with stigmasterol and β-sitosterol notably enhanced the cholesterol-reducing activity. TEM studies suggested the hydrogen bonding of EGC strengthened the aggregation network of ESi and ESt in the bile salt micelle. The exceptional properties of ESi and ESt signified their intriguing utilization in the food industry.

Optimized hydrolytic methods by response surface methodology to accurately estimate the phenols in cereal by HPLC-DAD: The case of millet

Extraction of free and bound phenols from millet in acidic and basic hydrolytic conditions were compared for the first time. Acidic hydrolysis was able to extract the highest amount of total phenolic compounds (up to 178 mg/100 g) while the basic hydrolysis underestimates the phenolic concentration. Our findings pointed out for the first time that methyl ferulate is naturally present as bound phenol in millet. Response Surface Methodology was then applied to both acidic and basic hydrolytic extractive conditions: the acidic procedure, optimized in terms of extractive time and temperature and concentration of the acidic mean, gave the best results, allowing definition of Method Operable Design Region and quantitation of the total amount of phenols in millet samples in a single extractive step. This optimized method is suitable for further accurate investigations of the typical phenols of the numerous varieties of this recently re-discovered minor cereal.