Individual Phenolic Acids Research Articles

Influence of germination time on free amino acids, phenolic compounds and γ-aminobutyric acid in pigeon pea (Cajanus cajan (L.) Huth) seeds

This research studied the influence of phytochemical compounds on the germination time of pigeon pea (Cajanus cajan (L.) Huth). Over the 72 hours germination period, the contents of total and most individual free amino acids, particularly histidine, showed substantial increases. The content of γ-aminobutyric acid (GABA) was also greatly increased, from 0.24 µg/g to 2.7 µg/g, representing a nearly ninefold increase. The total phenolic content (TPC) and total flavonoid content (TFC) were positively related with germination time, with TPC highest at 62.49 mg GAE/100 g DW at 72 h, and TFC increased from 18.87 mg RE/100 g DW to 30.05 mg RE/100g.DW at 72 hours. The contents of individual phenolic acids and flavonoids, such as, protocatechuic acid, p-coumaric acid, ferulic acid and rutin, experienced noticeable increases. However, vanillic and catechin were only detectable at 72 hours, respectively. Antioxidant capacity measured by DPPH and FRAP assays increased from 102.30 to 128.95 mgTE/100g DW and 694.13 to 836.93 mg FeSO4/100g DW mmol/g, respectively, and therefore highlighting the enhanced antioxidant potential of germinated pigeon pea. The results from Fourier-transform infrared spectroscopy (FTIR) supported these findings. The study emphasizes the potential of germination to enhance the phytochemical compounds of pigeon pea seeds.

The functional and nutritional properties of a novel Monascus fermented rice rich in resistant starch

Rice high in resistant starch (RS) showed great benefits in preventing diabetes. Red mold rice (RMR) is a traditionally functional food in China, preparing RMR with high-RS rice might produce a novel RMR with better nutrients and promote the utilization of high-RS rice in the food industry. R4 with the highest RS content was the most prone to be fermented by Monascus. After fermentation, the total starch and protein contents were significantly decreased, while the RS, lipid, free glucan, total free amino acids (FAAs), and γ-aminobutyric acid (GABA) contents were remarkably increased. Concurrently, the phenolic content and antioxidation activity were enhanced greatly. The individual phenolic acids such as ferulic acid showed significantly positive correlations with the antioxidant activity. Besides the abundant lipids, FAAs, GABA, and strong antioxidant capacity, fermented R4 had the highest ferulic acid content. This study provided alternatives for producing novel RMR and widened applications of high-RS rice in innovative functional foods.

In Vitro Digestion of Polyphenolic Compounds and the Antioxidant Activity of Acorn Flour and Pasta Enriched with Acorn Flour

Acorn flour is a rich source of nutrients and is beneficial to human health due to, among other things, its low glycemic index and polyphenol content. In order to obtain more accurate data on the levels and activities of the substances tested after ingestion and digestion, it may be beneficial to use a simulated in vitro digestion method. Therefore, the objective of the present study was to elucidate the content of polyphenols, individual phenolic acids, flavonoids and antiradical properties of acorn flour and pasta enriched with acorn flour before and after simulated in vitro gastrointestinal digestion. The results indicate that the total polyphenol content (TPC), flavonoid content and radical scavenging activity exhibited an increasing trend following the initial digestion stage and a decreasing trend following the second stage. Nevertheless, the levels of phenolic acids demonstrated an increase in both digestion phases. The digestion processes of polyphenols in acorn flour differ significantly from those in pasta. In the case of pasta, total polyphenols, phenolic acids and flavonoids, as well as free radical scavenging properties, demonstrated a decreasing trend following each digestion stage.

Investigating the Anti-Inflammatory Properties and Skin Penetration Ability of Cornelian Cherry (Cornus mas L.) Extracts.

Plant extracts can be a valuable source of biologically active compounds in many cosmetic preparations. Their effect depends on the phytochemicals they contain and their ability to penetrate the skin. Therefore, in this study, the possibility of skin penetration by phenolic acids contained in dogwood extracts of different fruit colors (yellow, red, and dark ruby red) prepared using different extractants was investigated. These analyses were performed using a Franz chamber and HPLC-UV chromatography. Moreover, the antioxidant properties of the tested extracts were compared and their impact on the intracellular level of free radicals in skin cells was assessed. The cytotoxicity of these extracts towards keratinocytes and fibroblasts was also analyzed and their anti-inflammatory properties were assessed using the enzyme-linked immunosorbent assay (ELISA). The analyses showed differences in the penetration of individual phenolic acids into the skin and different biological activities of the tested extracts. None of the extracts had cytotoxic effects on skin cells in vitro, and the strongest antioxidant and anti-inflammatory properties were found in dogwood extracts with dark ruby red fruits.

Unveiling the distribution of free and bound phenolic acids, flavonoids, anthocyanins, and proanthocyanidins in pigmented and non-pigmented rice genotypes.

The total phenolic content, phenolic acid profile, anthocyanins, proanthocyanidins, flavonoids, and antioxidant capacity of the whole-grain and bran portion of sixteen distinct rice genotypes that correspond to three distinct pericarp bran colors-black, red, and non-pigmented (NP)-were examined. Ten free and bound phenolic acids, as well as two flavonoids, were analyzed using HPLC-PDA. The flavonoids included kaempferol and catechin hydrate, and the free phenolic acids included gallic acid, 2,5-dihydroxybenzoic acid, vanillic acid, syringic acid, p-coumaric acid, chlorogenic acid, trans-cinnamic acid, trans-ferulic acid, p-coumaric acid, and sinapic acid. Trans-ferulic acid (207.39 mg/kg), p-hydroxybenzoic acid (94.36 mg/kg), and p-coumaric acid (59.75 mg/kg) were the principal bound phenolic acids in pigmented rice genotypes, whereas in NP genotypes they were trans-ferulic acid (95.61 mg/kg) and p-hydroxybenzoic acid (58.32 mg/kg). The main free phenolic acid was syringic acid (120.43 mg/kg) in all genotypes. 2,5-dihydroxybenzoic acid was also detected in NP genotypes, mainly in the bound form (4.88 mg/kg). NP genotypes Basmati 386 and Punjab Basmati 7 also displayed high content of bran flavonoids (1001 and 1028 mg CE/100g). The bound form of phenolics had significant DPPH and ABTS + activity. This study found wide diversity in the phenolic acid profile, total phenolic constituents, and antioxidant activity in the bran and whole grain of pigmented and NP rice. The individual phenolic acids in free and bound forms in different fractions of the grain were found to exert their antioxidant activity differently. The results obtained will provide new opportunities to improve the nutritional quality of rice with enhanced levels of phytochemicals in the ongoing breeding programs. Black rice bran contains a high level of phytochemicals and thus has a potent pharmaceutical role. This information would enhance the use of whole-grain and bran of pigmented rice in food product development by food technologists. Further studies may be focused on clinical trials with respect to cancer and diabetes.

Microwave hydrodistillation of Pelargonium graveolens L’Her leaves: Essential oil profile, phytochemical composition of wastewater, histo-anatomical structure

By-products with remarkable bioactive properties are formed in extraction processes of essential oils from plant materials. In present study, it was aimed to determine the concentration of individual phenolic and organic acid compounds by LC-MS/MS of the by-product (wastewater) collected after the essential oil isolation from Pelargonium graveolens L. and to determine some bioactive properties of this by-product. In addition, the chemical analysis and antibacterial activity of the essential oil extracted from P. graveolens were determined and the histo-anatomical characterization of the glandular trichomes in the leaf sample was performed. As a result, quercetin (95862.22 μg/kg), myricetin (59834.32 μg/kg) and rutin (36522.90 μg/kg) were the phenolic compounds determined in the highest concentrations in the by-product extracted using two different extraction techniques (non-hydrolysis and hydrolysis methods). Moreover, the individual organic acids of the by-product screened in LC-MS/MS was found to be 4487.17 mg/kg in total. When the essential oil component profile of the plant sample was examined, the citronellol (38.78%) compound was found to be dominant, and it was also detected that the essential oil had remarkable bioactive properties. In conclusion, it can be stated that both the essential oil obtained from P. graveolens and the by-product obtained during essential oil isolation can be considered as a source of some bioactive components in many different industrial applications.

General characteristics of lavender biomass (Lavandula angustifolia Mill.) before and after industrial distillation

The aim of the present study was to evaluate and compare three types of lavender (Lavandula angustifolia Mill.) biomasses for their content of biologically active substances and potential application. The first one was from unprocessed lavender (L-UNTR22_Z) and the other two were industrial steam-distilled lavender solid residues (L-SD22_Z and L-SD22_M). Ash, protein, polyuronide content and the degree of esterification of the pectic substances in the biomass were investigated. 70% ethanolic extracts of the residues were prepared and their total polyphenol content and antioxidant activity were evaluated by four methods. Individual phenolic acids, flavonoids, polar non-volatile compounds and polar volatile compounds were also determined by chromatographic analyses. The highest degree of esterification (83.9±0.5%) and protein content (8.15±1.6%) were found in L-SD22_Z extract. L-SD22_M extract demonstrated the highest polyphenolic content and antioxidant activity. Six phenolic acids (protocatehuic, syringic, p-coumaric, ferulic, salicylic, and gallic acid) and five flavonoids ((+)-catechin, (-)-epicatechin, rutin, hesperidin, and quercetin) were detected by HPLC analyses. The detail information about amino acids, sugars, organic and phenolic acids, as well as polar volatile compounds was obtained by GC-MS. The results suggested that the lavender (untreated and residual biomass) are a good source of dietary antioxidants and compounds with potent biological activity.

Flavonoid-Phenolic Acid Hybrids Are Potent Inhibitors of Ferroptosis via Attenuation of Mitochondrial Impairment.

Cinnamic acid, ferulic acid, and the flavonoids quercetin and taxifolin (dihydroquercetin) are naturally occurring compounds found in plants. They are often referred to as polyphenols and are known, among others, for their pharmacological effects supporting health through the inhibition of aging processes and oxidative stress. To improve their bioavailability, pharmacological activities, and safety, the creation of novel flavonoid-phenolic acid hybrids is an area of active research. Previous work showed that such hybridization products of phenolic acids and flavonoids enhanced the resilience of neuronal cells against oxidative stress in vitro, and attenuated cognitive impairment in a mouse model of Alzheimer's disease (AD) in vivo. Notably, the therapeutic effects of the hybrid compounds we obtained were more pronounced than the protective activities of the respective individual components. The underlying mechanisms mediated by the flavonoid-phenolic acid hybrids, however, remained unclear and may differ from the signaling pathways activated by the originating structures of the respective individual phenolic acids or flavonoids. In this study, we characterized the effects of four previously described potent flavonoid-phenolic acid hybrids in models of oxidative cell death through ferroptosis. Ferroptosis is a type of iron-dependent regulated cell death characterized by lipid peroxidation and mitochondrial ROS generation and has been linked to neurodegenerative conditions. In models of ferroptosis induced by erastin or RSL3, we analyzed mitochondrial (lipid) peroxidation, mitochondrial membrane integrity, and Ca2+ regulation. Our results demonstrate the strong protective effects of the hybrid compounds against ROS formation in the cytosol and mitochondria. Importantly, these protective effects against ferroptosis were not mediated by radical scavenging activities of the phenolic hybrid compounds but through inhibition of mitochondrial complex I activity and reduced mitochondrial respiration. Our data highlight the effects of flavonoid-phenolic acid hybrids on mitochondrial metabolism and further important mitochondrial parameters that collectively determine the health and functionality of mitochondria with a high impact on the integrity and survival of the neuronal cells.

Influence of industrial blanching, cutting, and freezing treatments on in vitro gastrointestinal digestion stability of orange (Citrus sinensis L.) and lemon (Citrus limon L.) peel polyphenols.

Citrus peels, which are often discarded as waste in the food-processing industry, are rich sources of polyphenols. The aim of the current study was to investigate the influence of an industrial freezing process along with blanching and cutting pretreatments on the in vitro gastrointestinal digestion stability of orange (Citrus sinensis L.) and lemon (Citrus limon L.) peel polyphenols. The major polyphenols were identified and quantified with ultra-performance liquid chromatography-electrospray tandem mass spectrometry (UPLC-ESI-MS/MS) and high performance liquid chromatography-photodiode array detector (HPLC-PDA), respectively. The results revealed that hesperidin and chlorogenic acid were the predominant flavonoid and phenolic acids in orange peels whereas, for lemon peels, eriocitrin and caffeic acid were the dominant flavonoid and phenolic acids, respectively. Blanching pretreatment enhanced the levels of major flavonoids in orange and lemon peels (by 39-82% and 54-146%, respectively) (P < 0.05) after in vitro gastrointestinal digestion. On the other hand, the application of cutting treatment after blanching significantly reduced the levels of flavonoids (23-62%) (P < 0.05); however, there was no statistically significant difference between the phenolic acid levels of cut and uncut citrus peels. Overall, the bioaccessibility of individual flavonoids and phenolic acids from frozen orange peels was generally slightly lower than that of untreated peels (9-34% and 9-49%, respectively). Nevertheless, frozen lemon peels contained higher bioaccessible flavonoids and phenolic acids in comparison with untreated peels (40-172% and 32-98%, respectively). These results suggest that industrial freezing steps could largely preserve the bioaccessibility of polyphenols in orange and lemon peels. © 2023 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

CaCl2 promoted phenolics accumulation via the CmCAMTA4-mediated transcriptional activation of phenylpropane pathway and energy metabolism in fresh-cut cantaloupe

Phenolics are secondary metabolites in plants. Calcium chloride (CaCl2) application could promote phenolics accumulation whereas the molecular mechanism remains uncertain. In this study, CaCl2 treatment reinforced the increase of individual phenolic acid content, PAL, C4H and 4CL activities and activated related expressions of CmPAL1, CmPAL2, CmPAL3, CmC4H1, CmC4H2, CmC4H3, Cm4CL1 and Cm4CL2 in fresh-cut cantaloupe. The total phenolics, total flavonoids content and antioxidant capacity in CaCl2-treated fresh-cut cantaloupe were 39.53%, 33.33% and 23.08% higher than those in control fruit after 24 h of storage, respectively. In the meantime, CaCl2 application elevated of H+-ATPase, Ca2+-ATPase, SDH, CCO activities and elicited the transcription of CmH+-ATPase4, CmCa2+-ATPase2, CmSDH5 and CmCCO6 genes in fresh-cut cantaloupe. Moreover, CmCAMTA4, an up-regulated calmodulin-binding transcription activator (CAMTA) induced by CaCl2 was identified in fresh-cut cantaloupe. Further study suggested that CmCAMTA4 could bind the CG-box in the promoter region of CmPAL3, Cm4CL1 and CmCCO6 to activate their transcription. In summary, these findings indicated that CaCl2 treatment could activate the transcription of CmPAL3, Cm4CL1 and CmCCO6 mediated by CmCAMTA4, which stimulated the phenylpropane pathway and maintained higher energy status, thus facilitating the biosynthesis of phenolics in fresh-cut cantaloupe during storage.

Polyphenol-rich diet mediates interplay between macrophage-neutrophil and gut microbiota to alleviate intestinal inflammation

Dietary phenolic acids alleviate intestinal inflammation through altering gut microbiota composition and regulating macrophage activation. However, it is unclear how individual phenolic acids affect the interactions between intestinal microbiota and macrophages in the context of inflammatory bowel disease (IBD). Here, we aim to elucidate the mechanism by which phenolic acids alleviate gut inflammation. Mice with or without depletion of macrophages were administered with four individual phenolic acids including chlorogenic, ferulic, caffeic, and ellagic acids, following dextran sulfate sodium (DSS) treatment. Gut microbiota depletion and fecal microbiota transplantation were further performed in mice to investigate the role of the gut microbiota in phenolic acid-mediated protective effect. Colitis severity was evaluated using histological, serological, and immunological measurements. Absence of intestinal microbiota and macrophage deteriorate the epithelial injury in DSS colitis. Chlorogenic acid mitigated colitis by reducing M1 macrophage polarization through suppression of pyruvate kinase M 2 (Pkm2)-dependent glycolysis and inhibition of NOD-like receptor protein 3 (Nlrp3) activation. However, ferulic acid-mediated reduction of colitis was neutrophil-dependent through diminishing the formation of neutrophil extracellular traps. On the other hand, the beneficial effects of caffeic acid and ellagic acid were dependent upon the gut microbiota. In fact, urolithin A (UroA), a metabolite transformed from ellagic acid by the gut microbiota, was found to alleviate colitis and enhance gut barrier function in an IL22-dependent manner. Overall, our findings demonstrated that the mechanisms by which phenolic acid protected against colitis were resulted from the interaction between gut microbiota and macrophage-neutrophil.

Contribution of Insoluble Bound Antioxidants from Germinated Seeds of Wheat and Spelt to the Nutritional Value of White Bread.

This research aimed to study the dynamic changes in phenolic antioxidants between the germ and the rest of the germinated seed of wheat and spelt and to evaluate the whole grain flour from germinated seeds as a functional supplement. Longer germination resulted in higher TPC, DPPH, and ABTS values when considering the entire germinated seed, while the optimal germination time was not consistent when considering the germ and the remaining germinated seed separately. While in the germinated seed (without germ) the majority of TPC was determined to be bound phenolics (up to 92%), the extractable form dominated in the germ (up to 69%). The most abundant phenolic antioxidants in germinated wheat and spelt seeds, trans-ferulic acid, cis-ferulic acid, and p-coumaric acid, increased significantly with germination. Only breads with 5% germinated spelt or wheat flour were suitable for the production of a food product, showing higher extractable TPC, antioxidant activity, individual phenolic acids, and improved specific volume, and were preferred because of their appearance, aroma, and color. The PCA biplot showed that the addition of 15% and 30% germinated flours had the greatest positive impact on phenolic properties, while breads with the addition of 5% germinated flour had the greatest positive impact on specific volume and color.

Phenolic profile of whole seeds and seed fractions of lentils and its impact on antioxidant activity

Seed color and size are the major traits influencing consumer's acceptability and market class of lentils worldwide. In this paper we assessed the in vitro antioxidant capacity of whole seeds, hulls, and cotyledons of five lentil varieties in relation to their phenolic profile. The samples were evaluated for total polyphenol content and different phenolic classes, such as condensed tannin content, total monomeric anthocyanins, and phenolic acids. Individual phenolic compounds, including flavonols, flavanols, flavones, anthocyanins, and phenolic acids, were further quantitatively investigated by HPLC-DAD. Total antioxidant capacity was evaluated by ABTS and ORAC assays, and a direct measurement (ABTSdir) was used to evaluate the antioxidant capacity of the bioactive compounds present in the whole-meal flours without extraction. The five genotypes showed considerable variations in their phenolic content and profile as well as antioxidant activities. The results showed a preferential accumulation of phenolic compounds with antioxidant activity in the hulls compared to cotyledons. Delphinidin and cyanidin were the most abundant flavonoids in the hulls, while epicatechin and catechin were the most concentrated in the cotyledons. A highly significant correlation was observed between ABTS, ORAC and ABTSdir and total polyphenols. The antioxidant capacities were highly correlated with several individual phenolics detected in hulls and cotyledons. The overall results showed that the lentil fractions and extracts with higher phenolics had also higher antiradical activity which was independent on seed size and color. Identifying lentil genotypes with diverse phenolic profile in cotyledons and whole seeds could meet diverse consumers preferences and health requirements.

Investigating the Content and Bioaccessibility of Phenolic Compounds In Roots of Rosa canina L. and Rosa pimpinellifolia L.

Rosehip is among the most important plants with high economic value, mainly used in foods and beverages from ancient times to the present. In this study, Rosa canina L. and Rosa pimpinellifolia L. roots, consumed as tea in Aktoprak Village of Erzurum province, were collected together with the fruits. The main goal of the study was to investigate the in vitro bioaccessibility of phenolic compounds in the roots and fruits of R. canina and R. pimpinellifolia by a simulated gastrointestinal digestion procedure. Methanolic and aqueous extracts were prepared for the analysis of phenolic compounds in roots, whereas only methanolic extracts were used for the analyses of fruits. Total phenolic and total flavonoid contents were evaluated spectrophotometrically, while four different methods were used for antioxidant capacity measurements. The quantification of individual phenolic acids, flavonoids, and anthocyanins was performed with HPLC-PDA. Results demonstrated that R. canina and R. pimpinellifolia have high levels of total phenolics, total flavonoids, and antioxidant capacity. The roots of R. pimpinellifolia and R. canina were observed to contain higher amounts of phenolics compared to the fruits. Epicatechin, 4-hydroxybenzoic acid, gallic acid, syringic acid, p-coumaric acid, naringenin, and ellagic acid were not determined in the fruit extracts of R. pimpinellifolia and R. canina, while they were detected in aqueous extracts of roots. Bioaccessibility analyses carried out on aqueous root extracts showed total phenolic recovery was 12.73% in R. canina, 10.71% in R. pimpinellifolia, and total flavonoid recovery was 0% in both species.

Effects of methionine treatment on storage quality and antioxidant activity of postharvest jujube fruit

Jujube fruits usually suffer from physiological disorders or infectious diseases during storage, leading to quality deterioration, softening, or rotting. Therefore, this study aims to investigate the effect of methionine soaking treatment on the postharvest jujube fruit decay rate and storage quality. Methionine treatment significantly reduced the decay rate of postharvest jujube fruit and effectively maintained fruit color and titratable acid. Methionine treatment effectively delayed the decrease of firmness, soluble solids, ascorbic acid, and lignin contents in jujube fruit. Methionine treatment reduced the content of alanine and phenylalanine, and increased the content of glycine in jujube fruit, but displayed no significant effect on total amino acid content. In addition, jujube fruits in the methionine treatment group had a higher total phenolic and flavonoid content and antioxidant capacity, both in free and bound forms. Compared with the control, methionine treatment also significantly increased the content of individual phenolic acid fractions (gallic acid, vanillic acid, and syringic acid) and flavonoid fractions (catechin, epicatechin, rutin) in free form as well as individual phenolic acid fractions in bound form (gallic acid and ferulic acid) in jujube fruits. Overall, this study suggested that the methionine treatment could be used as a prospective preservative to reduce the postharvest decay of jujube fruit and alleviate its nutritional quality deterioration during cold storage at 4°C.

The Use of Carbon Dioxide as a Green Approach to Recover Bioactive Compounds from Spent Coffee Grounds.

Spent coffee grounds (SCG) contain bioactive compounds. In this work, given the increasing demand to valorize waste and use green technologies, SCG were submitted to extraction by carbon dioxide (CO2) in supercritical and liquid conditions. The extraction parameters were varied to obtain the maximum yield with the maximum antioxidant activity. The use of supercritical and liquid CO2 with 5% ethanol for 1 h provided yields (15 and 16%, respectively) comparable to those obtained by control methods for 5 h and extracts with high total polyphenolic contents (970 and 857 mg GAE/100 g oil, respectively). It also provided extracts with DPPH (3089 and 3136 μmol TE/100 g oil, respectively) and FRAP (4383 and 4324 μmol TE/100 g oil, respectively) antioxidant activity levels higher than those of hexane extracts (372 and 2758 μmol TE/100 g oil, respectively) and comparable to those of ethanol (3492 and 4408 μmol TE/100 g oil, respectively). The SCG extracts exhibited linoleic, palmitic, oleic, and stearic acids (predominant fatty acids) and furans and phenols (predominant volatile organic compounds). They were also characterized by caffeine and individual phenolic acids (chlorogenic, caffeic, ferulic, and 3,4-dihydroxybenzoic acids) with well-known antioxidant and antimicrobial properties; therefore, they could be used in the cosmetic, pharmaceutical, and food sectors.

Conversion of endogenous phenolic acid in brown rice by bioextrusion of mesophilic α-amylase

Thermomechanical process is the most commonly used for treating grains but inevitably cause loss of endogenous bioactive ingredients such as phenolics. This work investigated the phenolic retention of brown rice via bioextrusion at different concentration gradients of mesophilic α-amylase (MαA, 0–2000 U/g), and determined the conversion of individual phenolic acids at both free and bound forms. Results showed that extrusion promoted the release of phenolics but lead to a great loss of them. While the phenolic retention of brown rice was significantly increased with increasing MαA levels up to 1000 U/g (twice more than that of traditional extrudate), which simultaneously modified rice matrix from big granules to small ones by SEM observation. The viscosity of bioextruded brown rice was decreased significantly but negatively relating to phenolic retention. Extrusion kinetics revealed that mechanical input and residence time had obvious effects on starch gelatinization which ultimately influence the presence of phenolics.

The combined effect of cold plasma pretreatment and germination on nutritional quality and texture properties of brown rice cakes

SummaryThis work evaluated the combined influence of cold plasma pretreatment and germination on phytic acid, GABA, γ‐oryzanol, phenolics, antioxidant activity, in vitro starch digestibility and texture characteristics of brown rice cakes. The contents of GABA, total γ‐oryzanol, total phenolics, total flavonoids, individual phenolic acid, individual flavonoid and antioxidant activity in germinated brown rice cake with cold plasma pretreatment (CGRC) were significantly higher than those in white rice cake (WRC) and brown rice cake (BRC), and the phytic acid content of CGRC was lower than that in BRC. Compared with WRC and BRC, CGRC had the highest content of resistant starch and the lowest starch in vitro digestibility. Additionally, the textural characteristics of CGRC were enhanced with lower hardness and higher elasticity compared to WRC and BRC. The combination of cold plasma pretreatment and germination may be the prospective approach for enhancing the nutritional quality and textural properties of brown rice cakes.

The profile of phenolic compounds by HPLC-MS in Spanish oak (Quercus) honeydew honey and their relationships with color and antioxidant activity

Due to the importance of the authentication of the botanical and geographical origin of honey, this document is focused on the use of phenols as potential chemical markers in an attempt to distinguish and characterize one of the non-floral honey types, oak (Quercus sp.) honey, from other honeydew honeys produced in other regions. The development and validation of ultra-high-performance liquid chromatography with mass spectrometry detection enables the identification of 23 phenolic compounds in 58 Spanish oak honeydew honey samples. The proposed compounds, above all salicylic acid (mean = 24.31 mg 100 g−1), but also p-coumaric acid, p-hydroxybenzoic acid, syringic acid, naringenin, and galangin could further contribute as a helpful tool in the quality control of this non-floral honey, and therefore distinguish it from European honeydew honey and those from other regions. Furthermore, many positive correlations between phenolic compounds, CIELAB color parameters, and antioxidant activity are established. This research presents a complete phenolic composition and the largest sampling of one of the most appreciated honeydew honey varieties. This is also one of the singular studies that have successfully linked individual phenolic acids and flavonoids with physicochemical parameters within the same unifloral honey.

Phenolic Acids Profiles and Phenolic Concentrations of Emmer Cultivars in Response to Growing Year under Organic Management.

Phenolic compounds, especially phenolic acids (PAs), are believed to be one of the major contributors to the antioxidant activity of cereal grains. This study determined and compared phenolic concentration, radical scavenging activities, individual PA concentrations of emmer cultivars, and breeding lines to common wheat in a three-year controlled field experiment under organic management. It was found that common wheat had the highest ability to scavenge DPPH radicals (51.7%), followed by emmer Farvento (35.4%). DPPH scavenging activity of bound phenolic extracts was higher compared to free ones. Total phenolic concentration was the highest for common wheat (1902.6 µg FAE g-1 DM) compared to the highest level of all emmer cultivars-Farvento (1668.3 µg FAE g-1 DM). The highest PAs concentration was determined for emmer Farvento (431.3 µg g-1 DM) and breeding line PN 4-41 (424.5 µg g-1 DM). Free PAs concentration was the lowest for common wheat (29.5 µg g-1 DM). The dominant free PA was ferulic (66.3%), followed by syringic (11.7%), sinapic (7.4%), p-hydroxybenzoic (5.3%), salicylic (3.8%), p-coumaric (3.6%), and caffeic (2.1%). Bound ferulic acid accounted for 94.0% of total bound PAs, followed by p-coumaric (2.8%), p-hydroxybenzoic (0.8%), syringic (0.8%), caffeic (0.6%), sinapic (0.6%), and salicylic (0.4%). Emmer cultivar Farvento was distinguished by the highest concentration of individual free and bound forms of PAs. Effect of growing year was more evident on the concentration of free PAs compared to bound PAs. Extremely dry and hot weather during maturity stages has a negative impact on analysed free and bound PAs.