The combined effect of protein hydrolysis and Lactobacillus plantarum fermentation on antioxidant activity and metabolomic profiles of quinoa beverage

Metabolite profiling, antioxidant and anti-glycemic activities of Tartary buckwheat processed by solid-state fermentation(SSF)with Ganoderma lucidum

The aim of this study was to investigate the effect of Ganoderma lucidum fermentation on antioxidant and anti-glycemic activities of Tartary buckwheat. Xylanase, total cellulase (CMCase and FPase) and β-glucosidase in fermented Tartary buckwheat (FB) increased significantly to 242.06 U/g, 17.99 U/g and 8.67 U/g, respectively. And the polysaccharides, total phenols, flavonoids and triterpenoids, which is increased by 122.19%, 113.70%, 203.74%, and 123.27%, respectively. Metabolite differences between non-fermented Tartary buckwheat (NFB) and FB pointed out that 445 metabolites were substantially different, and were involved in related biological metabolic pathways. There was a considerable rise in the concentrations of hesperidin, xanthotoxol and quercetin 3-O-malonylglucoside by 240.21, 136.94 and 100.77 times (in Fold Change), respectively. The results showed that fermentation significantly increased the antioxidant and anti-glycemic activities of buckwheat. This study demonstrates that the fermentation of Ganoderma lucidum provides a new idea to enhance the health-promoting components and bioactivities of Tartary buckwheat.

Use of Transcriptomics to Reveal the Joint Immunotoxicity Mechanism Initiated by Difenoconazole and Chlorothalonil in the Human Jurkat T-Cell Line

It is very important to evaluate the immunotoxicity and molecular mechanisms of pesticides. In this study, difenoconazole and chlorothalonil were evaluated for immunotoxicity by using the human Jurkat T-cell line, and the EC50 were 24.66 and 1.17 mg/L, respectively. The joint exposure of difenoconazole and chlorothalonil showed a synergistic effect at low concentrations (lower than 10.58 mg/L) but an antagonistic effect at high concentrations (higher than 10.58 mg/L). With joint exposure at a concentration of EC10, the proportion of late apoptotic cells was 2.26- and 2.91-fold higher than that with exposure to difenoconazole or chlorothalonil alone, respectively. A transcriptomics analysis indicated that the DEGs for single exposure are associated with immunodeficiency disease. Single exposure to chlorothalonil was mainly involved in cation transportation, extracellular matrix organization, and leukocyte cell adhesion. Single exposure to difenoconazole was mainly involved in nervous system development, muscle contraction, and immune system processes. However, when the joint exposure dose was EC10, the DEGs were mainly involved in the formation of cell structures, but the DEGs were mainly involved in cellular processes and metabolism when the joint exposure dose was EC25. The results indicated that the immunotoxicological mechanisms underlying joint exposure to difenoconazole and chlorothalonil are different under low and high doses.

Effect of lactic acid bacteria co-fermentation on antioxidant activity and metabolomic profiles of a juice made from wolfberry and longan

Lactic acid bacteria (LAB) fermentation is frequently employed to improve the nutritional, functional, and sensory characteristics of foods. Our study explored the effects of co-fermentation with Lacticaseibacillus paracasei ZH8 and Lactococcus lactis subsp. lactis YM313 on the physicochemical properties, antioxidant activity, and metabolomic profiles of wolfberry-longan juice (WLJ). Fermentation was carried out at 35 °C for 15 h. The results suggest that WLJ is a favorable substrate for LAB growth, reaching a total viable count exceeding 8 log CFU/mL after fermentation. LAB fermentation increased acidity, reduced the sugar content, and significantly impacted the juice color. The total phenolic and flavonoid contents of the WLJ and the antioxidant capacities based on 2,2-diphenyl-1-picrylhydrazyl (DPPH), ABTS radical scavenging abilities and FRAP were significantly improved by LAB fermentation. Nontargeted metabolomics analysis suggested that the contents of small molecule substances in WLJ were considerably affected by LAB fermentation. A total of 374 differential metabolites were identified in the juice before and after fermentation, with 193 significantly upregulated metabolites and 181 siginificantly downregulated metabolites. The regulation of metabolites is important for improving the flavor and functions of juices, such as L-eucylproline, Isovitexin, Netivudine, 3-Phenyllactic acid, vanillin, and ethyl maltol, ect. This study provides a theoretical foundation for developing plant-based foods fermented with LAB.

Effects of grafting methods and raw materials on the physicochemical properties and biological activities of phenolic acids grafted oat β-glucan

Phenolic acids are commonly used as food biological preservatives. Grafting phenolic acids onto polysaccharides could effectively enhance their biological activities and environmental stability to varying degrees. However, grafting methods and raw materials could affect the physical properties and biological activities of the phenolic acid-grafted polysaccharides. In this study, caffeic acid (CA) and gallic acid (GA) were grafted onto oat β-glucan (OG) and hydrolyzed oat β-glucan (OGH) through N,N'-carbonyldiimidazole-mediated (CDI) and 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide hydrochloride coupling N-hydroxysuccinimide (EDC/NHS) methods. Graft modification decreased the crystallinity and thermal stability of the conjugates, but retained good bioactivities for the conjugates. The antioxidant and bacteriostatic activities of the conjugates prepared by the EDC method were better than those of the CDI method, and the OGH-conjugates showed better biological activities than OG-conjugates. EDC-GAOGH showed best DPPH (89.78%) and ABTS (92.32%) scavenging activities. The inhibitory effect of EDC-GAOGH on Escherichia coli was significantly better than that of EDC-CAOGH, but for Staphylococcus aureus, the results are opposite, which indicating that different phenolic acid grafting products have different inhibitory effects on pathogenic microbes. In general, grafting phenolic acids onto OGH using EDC method is an effective strategy for preparing food biological preservative.

Untargeted Metabolomics and Physicochemical Analysis Revealed the Quality Formation Mechanism in Fermented Milk Inoculated with Lactobacillus brevis and Kluyveromyces marxianus Isolated from Traditional Fermented Milk

Traditional fermented milk from the western Sichuan plateau of China has a unique flavor and rich microbial diversity. This study explored the quality formation mechanism in fermented milk inoculated with Lactobacillus brevis NZ4 and Kluyveromyces marxianus SY11 (MFM), the dominant microorganisms isolated from traditional dairy products in western nan. The results indicated that MFM displayed better overall quality than the milk fermented with L. brevis NZ4 (LFM) and K. marxianus SY11 (KFM), respectively. MFM exhibited good sensory quality, more organic acid types, more free amino acids and esters, and moderate acidity and ethanol concentrations. Non-targeted metabolomics showed a total of 885 metabolites annotated in the samples, representing 204 differential metabolites between MFM and LFM and 163 between MFM and KFM. MFM displayed higher levels of N-acetyl-L-glutamic acid, cysteinyl serine, glaucarubin, and other substances. The differential metabolites were mainly enriched in pathways such as glycerophospholipid metabolism, arginine biosynthesis, and beta-alanine metabolism. This study speculated that L. brevis affected K. marxianus growth via its metabolites, while the mixed fermentation of these strains significantly changed the metabolism pathway of flavor-related substances, especially glycerophospholipid metabolism. Furthermore, mixed fermentation modified the flavor and quality of fermented milk by affecting cell growth and metabolic pathways.

Effect of conventional and microwave heating treatment on antioxidant activity of quinoa protein after simulated gastrointestinal digestion

Effects of microwave and traditional water bath treatment at different temperatures (70, 80, 90 ℃) on in vitro digestion rate and antioxidant activity of digestion products of quinoa protein were investigated. The results indicated microwave treatment at 70 ℃ produced the highest quinoa protein digestion rate and the strongest antioxidant activities of its digestion products (P < 0.05), which was further verified by the results of free amino, sulfhydryl group, gel electrophoresis, amino acid profiles and the molecular weight distribution of the digestion products. However, limited exposure of active groups induced by water bath treatment might decrease the susceptibility of digestive enzymes and subsequently lower the digestibility and antioxidant activities of quinoa protein. The results suggested that a moderate microwave treatment could be used as a potential way to enhance the in vitro digestion rate of quinoa protein, as well as increase the antioxidant activities of its digestion products.

Effect of honeysuckle leaf extract on the physicochemical properties of carboxymethyl konjac glucomannan/konjac glucomannan/gelatin composite edible film

Honeysuckle leaves are rich in bioactive ingredients, but often considered as agro-wastes. In this study, honeysuckle leaf extract (HLE) was added to the carboxymethyl konjac glucomannan/konjac glucomannan/gelatin composite edible film (CMKH). Compared to films without HLE addition (CMK), the water vapor barrier properties of CMKH slightly decreased, but the transmittance of the CMKH films in UV region (200-400 nm) as low as zero. The elongation at break of CMKH film was 1.39 ∼ 1.5 fold higher than those of CMK films. The DPPH and ABTS scavenging activity of CMKH-Ⅱ was 85.75% and 90.93%, respectively, which is similar to the equivalent content of Vc. The inhibition rate of CMKH-Ⅰ and CMKH-Ⅱ against Escherichia coli and Listeria monocytogenes were close to 90%, and the inhibition rate against Staphylococcus aureus were up to 96%. The results emphasized that the composite film containing 25% (v/v) HLE has potential application value in food preservation.

Dynamics changes in physicochemical properties, volatile metabolites, non-volatile metabolites, and physiological functions of barley juice during Bifidobacterium infantis fermentation

The purpose of this research was to explore the potential of Bifidobacterium infantis fermentation to modify the composition and physiological properties of barley juices. B. infantis JFM12 showed a potent capability to decrease the total sugar contents from 0.39 ± 0.01 mg/mL to 0.35 ± 0.01 mg/mL within 24 h of fermentation. The volatile metabolite profiles were enriched after B. infantis JFM12 fermentation, leading to the changes of 13 aldehydes, 11 ketones, 10 acids, 7 alcohols, and 6 esters. A total of 98 key non-volatile metabolites were identified in the barley juice between before and after B. infantis JFM12 fermentation, including 80 non-volatile metabolites that were remarkably increased and 18 non-volatile metabolites that were remarkably reduced. Furthermore, the antioxidant activities and lipase inhibitory activities of fermented barley juice were higher than those of unfermented barley juice. Overall, B. infantis JFM12 was beneficial in increasing the quality of barley juice.

Determining the changes in metabolites of Dendrobium officinale juice fermented with starter cultures containing Saccharomycopsis fibuligera FBKL2.8DCJS1 and Lactobacillus paracasei FBKL1.3028 through untargeted metabolomics

BACKGROUND

The present study aimed to investigate the changes in volatile components and metabolites of Dendrobium officinale (D. officinale) juice fermented with starter cultures containing Saccharomycopsis fibuligera and Lactobacillus paracasei at 28 ℃ for 15 days and post-ripened at 4 ℃ for 30 days using untargeted metabolomics of liquid chromatography-mass spectrometry (LC-MS) and headspace solid-phase microextraction-gas chromatography (HS-SPME-GC-MS) before and after fermentation.

RESULTS

The results showed that the alcohol contents in the S. fibuligera group before fermentation and after fermentation were 444.806 ± 10.310 μg/mL and 510.999 ± 38.431 μg/mL, respectively. Furthermore, the alcohol content in the fermentation broth group inoculated with the co-culture of L. paracasei + S. fibuligera was 504.758 ± 77.914 μg/mL, containing a significant amount of 3-Methyl-1-butanol, Linalool, Phenylethyl alcohol, and 2-Methyl-1-propanol. Moreover, the Ethyl L (-)-lactate content was higher in the co-culture of L. paracasei + S. fibuligera group (7.718 ± 6.668 μg/mL) than in the L. paracasei (2.798 ± 0.443 μg/mL) and S. fibuligera monoculture groups (0 μg/mL). The co-culture of L. paracasei + S. fibuligera significantly promoted the metabolic production of ethyl L (-)-lactate in D. officinale juice. The differential metabolites screened after fermentation mainly included alcohols, organic acids, amino acids, nucleic acids, and their derivatives. Twenty-three metabolites, including 11 types of acids, were significantly up-regulated in the ten key metabolic pathways of the co-culture group. Furthermore, the metabolic pathways, such as pentose and glucuronate interconversions, the biosynthesis of alkaloids derived from terpenoid and polyketide, and aminobenzoate degradation were significantly up-regulated in the co-culture group. These three metabolic pathways facilitate the synthesis of bioactive substances, such as terpenoids, polyketides, and phenols, and enrich the flavor composition of D. officinale juice.

CONCLUSIONS

These results demonstrate that the co-culture of L. paracasei + S. fibuligera can promote the flavor harmonization of fermented products. Therefore, this study provides a theoretical basis for analyzing the flavor of D. officinale juice and the functional investigation of fermentation metabolites.

An overview of the nutritional profile, processing technologies, and health benefits of quinoa with an emphasis on impacts of processing

Consumers are becoming increasingly conscious of adopting a healthy lifestyle and demanding food with high nutritional values. Quinoa (Chenopodium quinoa Willd.) has attracted considerable attention and is consumed worldwide in the form of a variety of whole and processed products owing to its excellent nutritional features, including richness in micronutrients and bioactive phytochemicals, well-balanced amino acids composition, and gluten-free properties. Recent studies have indicated that the diverse utilization and final product quality of this pseudo-grain are closely related to the processing technologies used, which can result in variations in nutritional profiles and health benefits. This review comprehensively summarizes the nutritional properties, processing technologies, and potential health benefits of quinoa, suggesting that quinoa plays a promising role in enhancing the nutrition of processed food. In particular, the effects of different processing technologies on the nutritional profile and health benefits of quinoa are highlighted, which can provide a foundation for the updating and upgrading of the quinoa processing industry. It further discusses the present quinoa-based food products containing quinoa as partial or whole substitute for traditional grains.

Simultaneously enhanced stability and biological activities of chlorogenic acid by covalent grafting with soluble oat β-glucan

Chlorogenic acid (CA) has a wide range of biological activities but the chemical structure is extremely unstable. In this study, CA was grafted onto a soluble oat β-glucan (OβGH) to improve the stability. Although the crystallinity and thermal stability of CA-OβGH conjugates reduced, the storage stability of CA significantly improved. The DPPH and ABTS scavenging ability of CA-OβGH IV (graft ratio 285.3 mg CA/g) were higher than 90 %, which is closed to activities of equivalent concentration of Vc (93.42 %) and CA (90.81 %). The antibacterial abilities of CA-OβGH conjugates are improved compared to the equivalent content of CA and potassium sorbate. Particularly, the inhibition rate of CA-OβGH for gram-positive bacteria (Staphylococcus aureus and Listeria monocytogenes) are significantly higher than that of gram-negative bacteria (Escherichia coli). The results demonstrated that covalent grafted CA with soluble polysaccharide is an effective strategy to enhance its stability and biological activities.

Comparative Transcriptome Analysis to Investigate the Immunotoxicity Mechanism Triggered by Dimethomorph on Human Jurkat T Cell Lines

Dimethomorph (DMM) is a broad-spectrum fungicide used globally in agricultural production, but little is known regarding the immunotoxicity of DMM in humans. In this study, the immunotoxicity of DMM on human Jurkat T cells was evaluated in vitro. The results indicated that the half-effective concentration (EC₅₀) of DMM for Jurkat cells was 126.01 mg/L (0.32 mM). To further elucidate the underlying mechanism, transcriptomics based on RNA sequencing for exposure doses of EC₂₅ (M21) and EC₁₀ (L4) was performed. The results indicated that compared to untreated samples (Ctr), 121 genes (81 upregulated, 40 downregulated) and 30 genes (17 upregulated, 13 downregulated) were significantly differentially regulated in the L4 and M21 samples, respectively. A gene ontology analysis indicated that the significantly differentially expressed genes (DEGs) were mostly enriched in the negative regulation of cell activities, and a KEGG pathway analysis indicated that the DEGs were mainly enriched in the immune regulation and signal transduction pathways. A quantitative real-time PCR for the selected genes showed that compared to the high-dose exposure (M21), the effect of the low-dose DMM exposure (L4) on gene expression was more significant. The results indicated that DMM has potential immunotoxicity for humans, and this toxicity cannot be ignored even at low concentrations.

Biological functions of active ingredients in quinoa bran: Advance and prospective

Quinoa is known to be a rich source of nutrients and bioactive components. Quinoa bran, used mainly as animal feed in processing by-products, is also a potential source of bioactive ingredients being conducive to human health. The importance of nutrition and function of quinoa seed has been discussed in many studies, but the bioactive properties of quinoa bran often are overlooked. This review systemically summarized the progress in bioactive components, extraction, and functional investigations of quinoa bran. It suggests that chemically assisted electronic fractionation could be used to extract albumin from quinoa bran. Ultrasound-assisted extraction method is a very useful method for extracting phenolic acids, triterpene saponins, and flavonoids from quinoa bran. Based on in vitro and in vivo studies for biological activities, quinoa bran extract exhibits a wide range of beneficial properties, including anti-oxidant, anti-diabetes, anti-inflammation, anti-bacterial and anti-cancer functions. However, human experiments and action mechanisms need to investigate. Further exploring quinoa bran will promote its applications in functional foods, pharmaceuticals, and poultry feed in the future.