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Chlorogenic acid (CGA) is a well-known plant secondary metabolite exhibiting multiple physiological functions. The present study focused on screening for synergistic antibacterial combinations containing CGA. The combination of CGA and p-coumaric acid (pCA) exhibited remarkably enhanced antibacterial activity compared to that when administering the treatment only. Scanning electron microscopy revealed that a low-dose combination treatment could disrupt the Shigella dysenteriae cell membrane. A comprehensive analysis using nucleic acid and protein leakage assay, conductivity measurements, and biofilm formation inhibition experiments revealed that co-treatment increased the cell permeability and inhibited the biofilm formation substantially. Further, the polyacrylamide protein- and agarose gel-electrophoresis indicated that the proteins and DNA genome of Shigella dysenteriae severely degraded. Finally, the synergistic bactericidal effect was established for fresh-cut tomato preservation. This study demonstrates the remarkable potential of strategically selecting antibacterial agents with maximum synergistic effect and minimum dosage exhibiting excellent antibacterial activity in food preservation.

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Melanins are dark-brown to black-colored biomacromolecules which have been thoroughly studied in animals and microorganisms. However, the biochemical and molecular basis of plant melanins are poorly understood. We first characterized melanin from the black radish (Raphanus sativus var. niger) 'HLB' through spectroscopic techniques. p-Coumaric acid was identified as the main precursor of radish melanin. Moreover, a joint analysis of transcriptome and coexpression network was performed for the two radish accessions with black and white cortexes, 'HLB' and '55'. A set of R2R3-type RsMYBs and enzyme-coding genes exhibited a coexpression pattern, and were strongly correlated with melanin formation in radish. Transient overexpression of two phenol oxidases RsLAC7 (laccase 7) or RsPOD22-1 (peroxidase 22-1) resulted in a deeper brown color around the infiltration sites and a significant increase in the total phenol content. Furthermore, co-injection of the transcriptional activator RsMYB48/RsMYB97 with RsLAC7 and/or RsPOD22-1, markedly increased the yield of black extracts. Spectroscopic analyses revealed that these extracts are similar to the melanin found in 'HLB'. Our findings advance the understanding of structural information and the transcriptional regulatory mechanism underlying melanin formation in radish.

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Unripe tomatoes are among the main waste produced during tomato cultivation and processing. In this study, unripe tomatoes from seven different Italian cultivars have been investigated to evaluate their nutraceutical potential. Phytochemical investigation allowed shedding light on the identification of seventy-five bioactive compounds. The highest amount of polyphenolic and glycoalkaloids along with the high level of antioxidant activities was found in the Datterini tomatoes variety. The peculiarity of this variety is the high chlorogenic acid content, being ten times higher compared to the other cultivars examined. Moreover, the total α-tomatine amount has been found substantially higher (34.699 ± 1.101 mg/g dry weight) with respect to the other tomato varieties analyzed. Furthermore, the cultivars metabolomic profiles were investigated with the PCA approach. Based on Datterini cultivar's metabolomic profile, its waste-recovery could represent a good option for further added value products in pharmaceutical and nutraceutical areas with a high α-tomatine content.

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Pyranoanthocyanins are anthocyanin-derived pigments with vivid colors and enhanced stability, making them promising food colorants. We evaluated two 4-vinylphenols, decarboxylated p-coumaric (pCA) and ferulic acid (FA), as cofactors for pyranoanthocyanin formation. Cyanidin-3-glycosides from saponified black carrot were incubated with 4-vinylphenol or 4-vinylguaiacol in different anthocyanin-to-cofactor molar ratios (1:1-1:30) to form pyranoanthocyanins. Formation efficiency (45 °C, ≤96 h) was compared to their respective precursors at a 1:30 ratio. Composition changes were monitored using uHPLC-PDA-ESI-MS/MS. Pyranoanthocyanin yields with 4-vinylphenol (13.8-33.4%) were ∼12× higher than with pCA and yields with 4-vinylguaiacol (8.1-31.0%) were ∼6.5× higher than with FA. Molar ratios of 1:5 and 1:10 yielded significantly more pyranoanthocyanins. Pyranoanthocyanin formation with 4-vinylphenols followed first-order kinetics, whereas formation with hydroxycinnamic acids followed zero-order kinetics. Detection of intermediate compounds was consistent with a nucleophilic addition and aromatization formation mechanism. Overall, pyranoanthocyanin formation with 4-vinylphenols was more efficient than with hydroxycinnamic acids.

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Interspecific metabolite transfer (ISMT) is a novel approach for plants biofortification. In this study, the effect of tea (Camellia sinensis; Cs), with or without membrane permeabilizers EDTA and Tween, as a donor plant on broccoli, cauliflower and kale sprouts was investigated. As a result, caffeine- and catechin-enriched broccoli, cauliflower and kale microgreens were produced. Kale sprouts were most permeable for catechins from Cs, while cauliflower was most permeable for caffeine. Cs + EDTA significantly increased vitamin C in broccoli and kale. Among the tested enzymes activity, pancreatic lipase was the most affected by the treatment with broccoli and cauliflower biofortified with Cs or Cs combined with permeabilizers. Broccoli sprouts biofortified with Cs most significantly inhibited α-amylase, while those biofortified with Cs combined with permeabilizers most significantly inhibited α-glucosidase. Results point to ISMT combined with membrane permeabilizers as a promising and eco-friendly biofortification strategy to improve the biopotential of Brassica microgreens.

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An environmentally friendly physical processing method, hydrothermal treatment (HT), was used to increase the content of specific compounds and antioxidant activities of seed-used pumpkin byproducts. The influence of hydrothermal temperature (80 °C-160 °C) and time (30-150 min) on changes in polyphenols and antioxidation was evaluated. The results revealed that the maximum free polyphenol content (140 °C for 120 min) was 3.96-fold higher than the untreated samples. Elevated temperature and long duration changed phenolic acid contents. For example, p-coumaric acid, rutin and chlorogenic acid exhibited a decreasing trend, and p-hydroxybenzoic acid, quercetin and cinnamic acid showed an increasing trend. Compared to controls, HT was significantly associated with increased antioxidant activities. To comprehensively reveal the influence of hydrothermal temperature and time on changes in polyphenolic content, back propagation artificial neural network (BP-ANN) models with accurate prediction ability were developed, and the results exhibited well-fitted and strong approximation ability (R2 > 0.95 and RMSE < 2 %) and stability.

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Experiments were performed to determine the effect of roasting whole wheat flours at 80 °C, 100 °C and 120 °C for 30 min on four forms of phenolics, Maillard reaction products (MRPs), and the DPPH scavenging activity (DSA) at 15, 30 and 45 days after flowering (15-DAF, 30-DAF, and 45-DAF). Roasting increased the phenolic content and antioxidant activity of the wheat flours, which were the dominant contributions to the formation of Maillard reaction products. The highest total phenolic content (TPC) and total phenolic DSA (TDSA) were determined in the DAF-15 flours at 120 °C/30 min. The DAF-15 flours exhibited the highest browning index and fluorescence of free intermediate compounds and advanced MRPs, suggesting that a substantial quantity of MRPs were formed. Four forms of phenolic compounds were detected with significantly different DSAs in the roasted wheat flours. The insoluble-bound phenolic compounds exhibited the highest DSA, followed by the glycosylated phenolic compounds.

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This study aims to explore whether ultra-high pressure (UHP) pre-treatment strengthened the bioaccessibility and bioactivities of the free (QF), esterified (QE) and insoluble-bound phenolics (QIB) from Que Zui tea (QT). The results revealed that the extraction yields, the total phenolic (TPC) and total flavonoid contents (TFC) of three phenolic fractions from QT were markedly increased after ultra-high pressure (UHP) processing (p < 0.05). A total of 19 and 20 compounds were characterized and quantified in non- and UHP-treated QT, respectively, including the content of 6'-O-caffeoylarbutin (11775.68 and 13248.87 µg/g of dry extract) was highest in QF, the content of caffeic acid was highest in QE (2131.58 and 7362.99 µg/g of dry extract) and QIB (9151.89 and 10930.82 µg/g of dry extract). QF, QE and QIB from QT after UHP processing had better antioxidant, ROS scavenging, and anti-apoptosis effects. The possible mechanism of cytoprotective effect was related to Keap1-Nrf2 pathway.

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ETHNOPHARMACOLOGICAL RELEVANCE: Rubus idaeus Linnaeus (RI) is a Chinese herbal medicine that has been widely used in China for a long time to reinforce the kidney, nourish the liver, improve vision, and arrest polyuria. AIM OF THE STUDY: This work aims to evaluate the recent progress of the chemical composition, pharmacological activity, pharmacokinetics, metabolism, and quality control and of Rubus idaeus, which focuses on the insufficiency of existing research and will shed light on future studies of Rubus idaeus. METHODS: Literatures about "Rubus idaeus","Red raspberry" and "Fupenzi"are retrieved by browsing the database, such as Web of Science (http://www.webofknowledge.com/wos), Pubmed (https://pubmed.ncbi.nlm.nih.gov/), CNKI (http://www.cnki.net/), and Wanfang Data (http://www.wanfangdata.com.cn). In addition, related textbooks and digital documents are interrogated to provide a holistic and critical review of the topic. The period of the literature covered from 1981 to 2022. RESULTS: Approximately 194 compounds have been isolated from Rubus idaeus, which is rich in phenols, terpenoids, alkaloids, steroids, and fatty acids. Numerous investigations have demonstrated that Rubus idaeus exhibits many pharmacological activities, including hypoglycemic and hypolipidemic, anti-Alzheimer effect, anti-osteoporosis, hepatoprotective, anti-cancer, neuroprotective, anti-bacteria and skin care, etc. However, it is worth noting that most of the research is not associated with the conventional effect, such as reducing urination and treating opacity of the cornea. CONCLUSION: The effectiveness of Rubus idaeus has been proved by its long-term clinical application. The research on the pharmacological activity of Rubus idaeus has flourished. In many pharmacological experiments, only the high-dose group can achieve the corresponding efficacy, so the efficacy of Rubus idaeus needs to be further interrogated. Meanwhile, the relationship between pharmacological activity and specific compounds of Rubus idaeus has not been clarified yet. Last but not least, studies involving toxicology and pharmacokinetics are very limited. Knowledge of bioavailability and toxicological behavior of Rubus idaeus can help understand the herb's pharmacodynamic and safety profile.

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A promising drying technology, namely combined freeze-drying and far-infrared drying (FD-FIRD) was employed to dehydrate seed-used pumpkin (SUP) and its effects on physical characteristics (color, microstructure, texture, shrinkage), bioactive components (phenolics and carotenoids) of SUP were evaluated. The low-field nuclear magnetic resonance (LF-NMR) was used to analyze moisture state and distribution during FD process, which is beneficial for choosing appropriate moisture transfer point. Results showed that most free water (87.29 %) was removed when drying time reached 25 h, thus retaining original tissue structure of sample with almost no deformation during later FIRD process. Therefore, FD for 25 h followed by FIRD for 2 h (FD25-FIRD2) sample exhibited similar appearance with FD sample. The free phenolics content of FD-FIRD samples was 14.97 %-26.60 % higher than that of FD depending on FIRD duration. Especially, p-coumaric acid content of FD25-FIRD2 sample increased of 32.23 %. Besides, FD-FIRD performed higher retention for carotenoids showing 3.00-3.39 folds than FIRD.

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Pickled radish is a general source of natural bioactive compounds that include phenols. Here, we used molecular docking, fluorescence quenching, circular dichroism spectroscopy and molecular dynamics simulations to identify potential inhibitors against xanthine oxidase from a library of pickled radish compounds. The most effective compounds were selected for validation through in vitro experiments including enzyme activity inhibition tests, and cell-based assays. Molecular docking results revealed that 2,6-Dihydroxyacetophenone, 4-Hydroxyphenethyl alcohol, and 4-Hydroxybenzaldehyde exhibited significant effects on xanthine oxidase inhibition. Three phenols have varying degrees of inhibition on xanthine oxidase, which is driven by hydrophobic interactions and hydrogen bonds and affects the secondary structure and hydrophobic homeostasis of xanthine oxidase. The stability of xanthine oxidase inhibition by three phenols was analyzed by molecular dynamics simulation. Finally, cellular experiments confirmed that three phenols reduced uric acid levels by inhibiting the xanthine oxidase enzyme activity of BRL 3A cells.

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Phenolics are a class of chemical compounds possessing antioxidant activity, which are mainly located in the wheat (Triticum aestivum) bran. Different approaches have been used in food industry to increase the availability of phenolics. Compared to these methods, however, genetic improvement of the wheat antioxidant potential, is a cost-effective, easier and safer approach. Here, we showed a single premature stop mutation in the keto-acythiolase-2 (kat-2b) gene, which significantly improved the antioxidant potential of pasta by a 60 ± 16% increase in its antioxidant potential by increasing the accumulation of ferulic acid. These changes are likely determined by the increased transcription (46% higher) and activity (120% higher) of the phenylalanine lyase genes observed in the mutated line compared to the control. Even if more studies will need to be done, overall, this study suggested that the kat-2b mutant could represent an excellent genetic resource to improve wheat's antioxidant and health-promoting potential.

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Brown rice bound phenolics extracts (BRBPE) have been reported to possess α-glucosidase inhibitory effects, the specific enzyme inhibitors involved in this process were unknown. Here, α-glucosidase inhibitors in BRBPE were screened using bioaffinity ultrafiltration methods, and seven phenolic compounds - three monomers (p-coumaric acid, ferulic acid and methyl ferulate), three dimers (8-5', 5-5' and 8-O-4' diferulic acid) and a trimer (5-5'/8-O-4″ dehydrotriferulic acid) were identified as exact inhibitors, among which 5-5'/8-O-4″ dehydrotriferulic acid and 5-5'diferulic acid exhibited the best inhibitory activity. Enzyme kinetic analysis suggested that the inhibitory mechanism of these seven inhibitors including competitive, noncompetitive, uncompetitive and mixed manner. Molecular docking analysis revealed that the seven inhibitors bind with α-glucosidase mainly by hydrogen bonding interaction, hydrophobic force and ionic bond. Molecular dynamics simulation further explored the structure and molecular property of phenolic-glucosidase complex. This work provided a deep insight into brown rice bound phenolics acting as potent α-glucosidase inhibitors.

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Enzymatic browning control of cloudy fruit juice with natural substances has received much attention for improving its nutritional and commercial value. This study explored the anti-browning potential of Rosa roxburghii in apple juice. The anti-browning effects and mechanisms were evaluated by serial measurements of appearance, browning index, polyphenol oxidase (PPO) activity, UPLC-QE-Orbitrap-MS identification, inhibition kinetics and molecular docking. The results showed that Rosa roxburghii juice (0.25%-1.25% w/w) could effectively inhibit browning and PPO activity of apple juice. Ascorbic acid (1.67 g/100 g) as a reducing agent was a main anti-browning factor. Furthermore, seven phenolic compounds in Rosa roxburghii were screened as PPO inhibitors. Representative phenolic inhibitors induced mixed or competitive inhibition of PPO, mainly driven by hydrophobic forces and hydrogen bonds. This work demonstrates that Rosa roxburghii is a promising natural anti-browning ingredient to control the browning of cloudy apple juice due to abundant ascorbic acid and PPO inhibitors.

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Chemical profiles, distribution, and antioxidant activity of bound phenolics from brown rice were investigated. Four new dehydrodiferulic acid dimers (DFA) along with eighteen known phenolics were isolated from brown rice bound phenolic extracts and their structures were determined by multiple spectroscopic methods. Among them, ferulic acid and 8-5' DFA were the most abundant monomeric and dimeric bound phenolics in brown rice, rice bran and polished rice. In whole brown rice, polished rice contributed more than 50% of three phenolic monomers and six phenolic dimers, while rice bran contributed more than half of the other thirteen phenolics including eight monomers, four dimers, and one trimer. All the isolated compounds exhibited oxygen radical absorbance capacity. Thomasidioic acid, caffeic acid, methyl caffeate, and 8-5' DC DFA displayed potent peroxyl radical scavenging capacity, and the last three compounds also showed moderate cellular antioxidant activity.

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4-Coumaroyl-CoA ligase (Al4CL) and chalcone synthase (AlCHS) genes were found in grape endophyte Alternaria sp. MG1, but were not functional verified. A cross-validation method was used in Saccharomyces cerevisiae to identify their functions. AlCHS was identified to synthesize both naringenin and resveratrol, while Al4CL synthesized p-coumaroyl CoA. Co-culture of S. cerevisiae strains separately containing AlCHS and Al4CL resulted in the simultaneous production of naringenin (18.5 mg/L) and resveratrol (113.2 µg/L). Strain S. cerevisiae containing Al4CL was used in winemaking and the chemical and aroma compounds in wine were detected by HPLC and SPME-GC-MS. Results showed that the total contents of polyphenols, anthocyanins, flavonol, ethyl esters and fatty acids significantly increased, while the 4-vinylphenol content decreased, and the fruit and cheese flavour increased but the green aroma declined. This study indicated the potential application of Al4CL and AlCHS genes from Alternaria sp. MG1 for improvement of wine nutrients and flavour.

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Photoperiod and temperature are vital environmental factors that regulate plant developmental processes. However, the roles of these factors in garlic bulb enlargement are unclear. In this report, responses of garlic bulb morphology and physiology to combinations of photoperiod (light/dark: 10/14 h, 12/12 h, 14/10 h) and temperature (light/dark: 25/18 °C, 30/20 °C) were investigated. For garlic cultivar G103, bulb characteristics, phytohormones (IAA, ABA, ZT, tZR, JA), allicin and phenolic acids (p-coumaric and p-hydroxybenzoic) were highest under a photoperiod of 14 h at 30 °C. Maximum GA was observed under 14 h + 30 °C for cv. G2011-5. Maximum caffeic, ferulic and vanillic acids were detected for cv. G2011-5 at 14 h + 30 °C, 12 h + 25 °C and 14 h + 25 °C, respectively. Flavonoids (myricetin, quercetin, kaempferol and apigenin) were not detected in this trial. This is the first report describing the impact of long periods of light duration and higher temperatures on garlic morphology, phytohormones, phenolic acids and allicin content.

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Phenolic acids (caffeic acid, p-coumaric acid,) and carotenes (ß-carotene, lycopene) were mixed in different ratios to investigate antioxidant interactions on H2O2-induced H9c2 cells with ezetimibe (inhibitor of carotenes membrane transporters). Cellular uptake of carotenes, expression of membrane transporters, reactive oxygen species (ROS), nuclear factor erythroid 2-related factor 2 (Nrf2), NAD(P)H dehydrogenase quinone1 (NQO1), heme oxygenase-1 (HO-1), glutamate-cysteine ligase catalytic subunit (GCLC) were analyzed. Results revealed that phenolic acids increased cellular uptake of carotenes and expression of their membrane transporters. Combination groups contained more phenolic acids showed synergistic effects. For example, ß-carotene: caffeic acid = 1:2 significantly suppressed the intracellular ROS (+EZT, 66.34 ±â€¯51.53%) and enhanced the accumulation of nucleus-Nrf2 (+EZT, 30.23 ±â€¯5.30) compared to the groups contained more ß-carotene (+EZT, ROS: 75.48 ±â€¯2.55%, nucleus-Nrf2: 19.48 ±â€¯4.22). This study provided an implication of functional foods formulation and demonstrated that antioxidant synergism may due to the up-regulation of carotenes membrane transporters by phenolic acids.

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Non-centrifugal cane sugar (NCS) samples obtained by traditional moulding and granulation, and also via a novel spray-drying powdering process without additives, were assessed to characterise their sugar and phenolic profiles, flavonoid content, as well as colour parameters. As expected, sucrose was the predominant sugar (91.9-95.5%), followed by glucose (2.9-4.6%), and fructose (1.6-3.7%). Total phenolic content was between 0.4 and 0.6% and total flavonoid content into the range of 0.2-0.4%. Six phenolic acids were found in all NCS samples: protocatechuic acid (0.36-0.94 µg/100 g), vanillic acid (0.70-1.45 µg/100 g), chlorogenic acid (2.08-3.82 µg/100 g), syringic acid (1.08-2.80 µg/100 g), p-coumaric acid (0.69-1.35 µg/100 g), and ferulic acid (0.50-0.95 µg/100 g). The thermal treatment under high temperatures required in the production of granulated products was related with darker colours and changes in phenol and flavonoid contents. In contrast, spray drying generates clearer products, but with slightly less phenol and flavonoid contents.

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In this study, fermentations were performed using simulated grape juice supplemented with terpene glycosides (TGs), extracted from Vitis vinifera L. Meili, and phenolic acids (gallic acid or p-coumaric acid). Free terpenes were detected using solid phase microextraction-gas chromatography-mass spectrometry (SPME-GC-MS) every day during the fermentation, and the aromas of final wines were evaluated by panelists. Quantum mechanical (QM) calculations performed at density functional level of theory were used to uncover the structural and thermodynamic properties of the binding between phenolic acids and free terpenes (or TGs). Results showed that phenolic acids remarkably inhibited TG hydrolysis and free terpene volatilization, and affected wine aroma perception. QM calculations revealed that phenolic acids can bind to linalool and its glycoside spontaneously (ΔG < 0) via hydrogen bonding and dispersive forces. These findings indicate that the matrix effect of phenolic acids can effectively control the release and modulate the global feature of wine aromas.

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