Increase In Flavonoid Content Research Articles

Effects of Peanut Shell Flavonoids on Composite Film Properties and Cherry Tomato Preservation

ABSTRACTThis study investigated the effects of varying concentrations of peanut shell flavonoids (PSFs) on the properties of peanut meal extract‐tilapia skin protein composite films and their impact on cherry tomatoes preservation. Peanut meal alcohol extract (Pe) and tilapia skin protein (Co) were used as base materials, combined with PSFs to prepare composite films with excellent antioxidant properties. The results demonstrated that the optimized composite films exhibited superior mechanical properties, with a tensile strength of 9.83 MPa and an elongation at break of 204.04%. Increased flavonoid content enhanced the films' antioxidant capacity, achieving superoxide anion and DPPH radical scavenging rates of 15.08% and 21.37%, respectively. The microstructure, IR spectra, and circular dichroism spectra of the composite films are also significantly different with the change of flavonoid content. In the cherry tomato preservation experiment, the PeCo‐0.5 composite film treatment group maintained a low weight loss rate (11.18%) and malondialdehyde content (13.33 μmol/g) after 15 days, delayed the peak respiration rate, and significantly reduced the peak respiration intensity (3.43 mgCO2∙ mg−1∙gh−1). At the same time, the activity of polyphenol oxidase in the tissue of Cherry Tomatoes was significantly inhibited, and the decrease rate of Vc content was also significantly decreased, which effectively preserving the bright color, smooth appearance, and good aroma of the cherry tomatoes. This study not only provides new insights into the comprehensive utilization of tilapia skin and peanut by‐products but also opens new avenues for the development and application of fruit and vegetable preservation films.

Secondary Metabolite of Bacopa monnieri Under Plant Growth Regulators Treatment on Fibroblast and Cancer Cells

Background: Bacopa monnieri L. is a significant medicinal herb with high economic and social value. Objectives: This study aimed to enhance the growth rate and the production of flavonoids and polyphenols using plant growth regulators (PGRs). Additionally, the study evaluated the effects of these metabolites on the viability of skin cancer cells (A375) and human fibroblast cells (HDF) in a completely randomized design with three replicates. Methods: For flavonoid extraction, samples were dried at 50°C. A total of 0.25 g of finely powdered dried sample was extracted with 20 mL of 60% (v/v) aqueous ethanol. The total phenolic and flavonoid content of B. monnieri was calculated. Human fibroblast cell lines (IBRC No. C10506) and skin cancer cells (A375; IBRC No. C11337) were cultured in an incubator maintained at 37°C, with 5% CO2 and high humidity. Results: The study found that 1 mg/L NAA yielded the highest flavonoid (1.76 mg/g DW) and polyphenol (35.17 mg/g DW) content. Among the cytokinins, 0.8 mg/L BAP produced the highest flavonoid (1.61 mg/g DW) and polyphenol (32.51 mg/g DW) content. The maximum viability of HDF cells (135%) was observed at 0.4 mg/L 2IP. The findings suggest that increasing flavonoid content in B. monnieri through various hormones is not recommended for skin cancer treatment. However, the use of 0.5 μg/mL 2IP significantly enhanced the growth of fibroblast cells. Conclusions: The results suggest that the application of 2IP in tissue culture of the B. monnieri plant can be beneficial for increasing fibroblast cell viability, making it a promising ingredient in cosmetics and health products. Further research is necessary to confirm these findings and optimize applications.

Ultraviolet-B Radiation Stimulates Flavonoid Biosynthesis and Antioxidant Systems in Buckwheat Sprouts.

Abiotic stress not only elevates the synthesis of secondary metabolites in plant sprouts but also boosts their antioxidant capacity. In this study, the mechanisms of flavonoid biosynthesis and antioxidant systems in buckwheat sprouts exposed to ultraviolet-B (UV-B) radiation were investigated. The findings revealed that UV-B treatment significantly increased flavonoid content in buckwheat sprouts, with 3-day-old sprouts exhibiting a flavonoid content 1.73 times greater than that of the control treatment. UV-B radiation significantly increased the activities of key enzymes involved in flavonoid biosynthesis (phenylalanine ammonia-lyase, 4-coumarate-CoA ligase, cinnamate 4-hydroxylase, and chalcone synthase) and the relative expression levels of the corresponding genes. Although UV-B radiation caused damage to the cell membranes of buckwheat sprouts, promoting increases in hydrogen peroxide and malondialdehyde content and inhibiting the growth of sprouts, importantly, UV-B radiation also significantly increased the activities of catalase, peroxidase, and superoxide dismutase as well as the relative expression levels of the corresponding genes, thus enhancing the antioxidant system of buckwheat sprouts. This enhancement was corroborated by a notable increase in ABTS, DPPH, and FRAP radical scavenging activities in 3-day-old sprouts subjected to UV-B radiation. Additionally, UV-B radiation significantly increased chlorophyll a and chlorophyll b contents in sprouts. These results suggest that UV-B radiation is advantageous for cultivating buckwheat sprouts with increased flavonoid content and enhanced antioxidant capacity.

Effects of exogenous calcium on flavonoid biosynthesis and accumulation in peanut roots under salt stress through multi-omics.

Flavonoids possess antioxidant properties and are crucial in enhancing plant resistance to abiotic stress. Exogenous calcium has been found to regulate the biosynthesis and accumulation of secondary metabolites, including flavonoids. However, the mechanism by which exogenous calcium influences flavonoid regulation in peanut roots under salt stress remains unclear. In this study, four treatment conditions were established: no salt stress, salt stress, exogenous calcium, and a combination of salt stress and exogenous calcium. The peanut root flavonoid profile was comprehensively analyzed using both a broadly targeted metabolomic approach and an absolute quantitative flavonoid metabolome. A total of 168 flavonoids were identified in the broad-target metabolome, while 68 were quantified in the absolute quantification analysis. The findings revealed that salt stress generally increased flavonoid content in peanut roots, while co-treatment with exogenous calcium significantly reduced this accumulation. Additionally, the activities of key enzymes and the expression of genes involved in the flavonoid biosynthesis pathway were upregulated under salt stress, but downregulated following the combined treatment. This study offers valuable insights into the physiological and ecological roles of flavonoids in response to environmental stressors in economically important crops.

Optimizing Greenhouse Cucumber Fertigation Through Grafting: Improving Yield, Bioactive Compounds, and Antioxidant Activity

Consumers prefer cucumbers (Cucumis sativus) with high antioxidant content, which is often at odds with farmers’ goals of maximizing yield. Therefore, this study aims to explore new methods for fertigation and grafting to optimize the yield and quality of cucumbers. In a greenhouse experiment, we tested fertigation with three different nutrient solutions: the standard as a control (CF) and two new formulations (NF1 and NF2). We also examined grafting in three variants: non-grafted (CG), grafting onto Cucurbita moschata × Cucurbita moschata (G1), and grafting onto Lagenaria siceraria (G2). Our results showed that the highest increase in phenolic content in the flesh of cucumber was observed in the NF2 × G1 treatment (↑ 22.4%). In contrast, grafting and the new fertigation methods generally reduced the phenolic content in the peel. Grafting with G1 significantly increased flavonoid content in the flesh (↑ 59.4% and ↑ 77.3%) but significantly decreased it in the peel. The NF2 × G1 treatment achieved the most significant increases in antioxidant activity indicators, DPPH (↑ 25.9%) and FRAP (↑ 39.4%). For farmers seeking to achieve high yields of greenhouse cucumbers, the combination of NF1 × G1 is recommended, as it resulted in the highest yield increase (↑ 45.3%). Consumers are advised to eat cucumbers with the peel, as this study found higher levels of antioxidant compounds in the peel compared to the flesh.

The Eliciting Effect of Aqueous Extracts from Ascophyllum nodosum Algae on the Cultivation of Arugula (Eruca sativa Mill.) Microgreens

This study showed the eliciting effect of aqueous extracts from Ascophyllum nodosum on the development of Eruca sativa microgreens in a quartz-based substrate. There is no information in the literature on the impact of its use on the quality, bioactive compound content, and nutritional value of arugula microgreens. Assays that have been made include the following: total phenolic content (TPC), total flavonoid content (TFV), enzymes such as phenylalanine ammonia (PAL) and polyphenol oxidase (PPO), and enzymes involved in the scavenging of reactive oxygen species such as catalase (CAT) and superoxide dismutase (SOD). The antioxidant activity against DPPH (2,2-diphenyl-1-picrylhydrazyl) was also evaluated. The total phenolic content of arugula microgreens increased significantly after an application of aqueous extracts of A. nodosum to the substrate. The greatest increase in flavonoid content (89%) and antioxidant activity against DPPH (82%) was observed at a concentration of 2.5%. The highest increase in activity of CAT (68.2%), SOD (25%), PAL (13-fold), and PPO (84.2%) was observed with the application of 5% extract. In conclusion, the use of Ascophyllum nodosum algae affects TPC and TFV, antioxidant activity, PAL, PPO, SOD, and CAT in the microgreens studied. By prioritising organic and environmentally friendly extracts, growers can contribute to a more sustainable and healthier food system, especially in the case of the production of Eruca sativa microgreens.

Developing a Symbiotic Fermented Milk Product with Microwave-Treated Hawthorn Extract

The rising interest in functional foods has increased the use of probiotics and prebiotics in fermented dairy products to enhance gut health. This study focuses on developing a symbiotic fermented milk product using Lactobacillus acidophilus and Bifidobacterium bifidum activated with hawthorn extract as a prebiotic. Three versions of the product were tested: a control and two variants with B. bifidum activated with 10−5 g/cm3 and 10−10 g/cm3 hawthorn extract, respectively. Key characteristics such as microbiological safety, sensory properties, amino acid profile, vitamin and mineral content, antioxidant capacity, and nutritional values were evaluated. Results showed that products enriched with hawthorn extract had favorable sensory properties and sustained high levels of lactic acid bacteria while being free of pathogens. Product 1 based on L. acidophilus and enriched with B. bifidum activated with hawthorn extract at a concentration of 10−5 g/cm3 demonstrated significant increases in L. acidophilus (24.1%) and B. bifidum (14.7%) after 7 days compared to the control. Both enriched products exhibited slower titratable acidity increases and higher viscosities over 14 days, indicating better preservation and texture stability. Product 1 was notably enriched with essential amino acids, vitamins, and minerals, alongside enhanced antioxidant properties due to increased flavonoid content. The technology developed ensures probiotic viability at 109–1010 CFU/cm3 after 14 days, making it viable for dairy production.

Flavonoid Biosynthesis in Scutellaria baicalensis Georgi: Metabolomics and Transcriptomics Analysis

Scutellaria baicalensis Georgi (SB), a plant of the Lamiaceae family, contains flavonoids with potent human health benefits. The full mechanistic details and regulatory networks related to the biosynthesis of these compounds in SB have been the focus of recent research but are still fragmented. Similarly, a complete account of the metabolites produced, specifically flavonoids, and their distribution in different parts of the plant is incomplete. To provide a more complete picture, herein we have explored the SB metabolites and differentially expressed genes in underground and aerial tissues. Of the 947 metabolites identified, 373 were differentially accumulated flavonoids (DAFs), and 147 of these were differentially accumulated in roots relative to other tissues. Interestingly, roots accumulated more baicalin and baicalein than aboveground tissues, but they were low in scutellarein and wogonoside, in contrast to previous reports. These differences may be attributed to either plant variety, age of the plants, or the extraction protocol. Transcriptomics analysis identified 56 key genes from the flavonoid synthesis pathway in all six SB plant tissues. A weighted gene correlation network analysis conducted using four DAFs (baicalin, baicalein, scutellarein and wogonoside) produced 13 modules. Baicalin and baicalein were positively correlated with one of these modules, whereas wogonoside and scutellarein were correlated with three other modules. Gene expression in these modules was consistent with the observed accumulation of these compounds in plant tissues. Fourteen structural genes were highly correlated with baicalin, baicalein and scutellarein, and 241 transcription factors (TFs) associated to these four compounds. The 13 highly correlated structural genes and 21 highly correlated TFs were used to construct correlation networks, where genes were identified to be highly correlated with flavonoid biosynthesis genes. Overexpression of some of these genes, namely, SbMYB8 (Sb02g25620), SbMYB14 (Sb09g00160) and SbbHLH94 (Sb07g11990), in SB callus increased flavonoid content and regulated the expression of genes involved in the flavonoid biosynthesis pathway, confirming their association to flavonoid production. Overall, the present work contributes to delineating the differences in flavonoid biosynthesis among different SB tissues.

The physiochemical characteristics and glycerolipid profile of Cycas panzhihuaensis in response to individual and combined drought and freezing temperature stress

The frequency and intensity of the occurrence of drought (D) events during winter are increasing in most areas of China. To explore the interactive effects of D and freezing temperature (F) on plants of endangered Cycas panzhihuaensis, some physiochemical characteristics and the lipid profile were determined. Drought and F stress had no or little impact on the traits of leaves, which, however, bleached following a combination of D and F treatment (DF). Drought treatment did not affect the chlorophyll fluorescence parameters and the flavonoid content of C. panzhihuaensis. Besides the increase in flavonoid content, a decrease of photochemical efficiency and an increase of heat dissipation were induced by both F and DF treatment, with the effects being greater in the latter treatment. The malondialdehyde content decreased significantly and the total antioxidant capacity increased significantly in the plants exposed to both D and DF treatments. The D treatment did not impact the amount of phospholipids but led to an accumulation of saccharolipids. Additionally, the amount of both phospholipids and saccharolipids remained unchanged following F treatment but decreased significantly following DF treatment compared with those of the control. The unsaturation level did not change significantly in most lipid classes of membrane glycerolipids following various stresses but increased significantly in phosphatidylserine, monogalactosylmonoacylglycerol, digalactosyldiacylglycerol and sulphoquinovosyldiacylglycerol following D or both D and F treatments. Generally, plants of C. panzhihuaensis showed relatively strong tolerance to individual D stress, while D aggravated the F-induced damage, which was likely caused by the degradation of the membrane glycerolipids.

Bacillus B2 promotes root growth and enhances phosphorus absorption in apple rootstocks by affecting MhMYB15.

Due to the chelation of phosphorus in the soil, it becomes unavailable for plant growth and development. The mechanisms by which phosphorus-solubilizing bacteria activate immobilized phosphorus to promote the growth and development of woody plants, as well as the intrinsic molecular mechanisms, are not clear. Through the analysis of microbial communities in the rhizosphere 16S V3-V4 and a homologous gene encoding microbial alkaline phosphomonoesterase (phoD) in phosphate-efficient (PE) and phosphate-inefficient apple rootstocks, it was found that PE significantly enriched beneficial rhizobacteria. The best phosphorus-solubilizing bacteria, Bacillus sp. strain 7DB1 (B2), was isolated, purified, and identified from the rhizosphere soil of PE rootstocks. Incubatingwith Bacillus B2 into the rhizosphere of apple rootstocks significantly increased the soluble phosphorus and flavonoid content in the rhizosphere soil. Simultaneously, this process stimulates the root development of the rootstocks and enhances plant phosphorus uptake. After root transcriptome sequencing, candidate transcription factor MhMYB15, responsive to Bacillus B2, was identified through heatmap and co-expression network analysis. Yeast one-hybrid, electrophoretic mobility shift assay, and LUC assay confirmed that MhMYB15 can directly bind to the promoter regions of downstream functional genes, including chalcone synthase MhCHS2 and phosphate transporter MhPHT1;15. Transgenic experiments with MhMYB15 revealed that RNAi-MhMYB15 silenced lines failed to induce an increase in flavonoid content and phosphorus levels in the roots under the treatment of Bacillus B2, and plant growth was slower than the control. In conclusion, MhMYB15 actively responds to Bacillus B2, regulating the accumulation of flavonoids and the uptake of phosphorus, thereby influencing plant growth and development.

Abscisic acid enhances alkaline stress tolerance in grapevines: Physiological and transcriptional profiling

Abscisic acid (ABA) is a crucial signaling regulator governing plant growth and survival during adverse conditions. However, the mechanism by which ABA mediates grapevine tolerance to alkali stress has not yet been elucidated. Here, we investigated the role of ABA in regulating physiological characteristics and transcriptome of grapevines under alkali stress through the application of exogenous ABA and fluridone (an ABA biosynthesis inhibitor). The results revealed that alkali stress led to significant reductions in the net photosynthetic rate (Pn), stomatal conductance (Gs), intercellular CO2 concentration (Ci), transpiration rate (Tr), chlorophyll content, the maximum quantum yields of primary photochemistry of PSII (Fv/Fm), nonphotochemical quenching (NPQ), which were greatly alleviated by exogenous ABA (50 and 100 μM) application. Specifically, the application of exogenous ABA (50 μM) increased Pn, chlorophyll content and Fv/Fm by 28.39 %, 30.45 % and 17.29 %, respectively, compared with alkali stress alone. Furthermore, exogenous ABA treatment reduced alkali stress-induced superoxide anions (O2∙−) and hydrogen peroxide (H2O2), malondialdehyde (MDA), and electrolyte leakage, as well as higher proline content and activities of superoxide dismutase (SOD), catalase (CAT), and ascorbate peroxidase (APX). Additionally, exogenous ABA (50 μM) decreased O2∙−, H2O2, MDA, electrolyte leakage by 38.64 %, 28.16 %, 39.29 % and 39.42 %, respectively, respect to alkali stress alone. Moreover, exogenous ABA reduced the Na+, increased K+ and K+/Na+ ratio, as well as the phenylalanine ammonia-lyase (PAL), chalcone synthase (CHS), chalcone isomerase (CHI) activities and flavonoid content, and increased zeaxanthin epoxidase (ZEP) and 9-cis-epoxy carotenoid dioxygenase (NCED) activities and endogenous ABA levels in alkali stress-treated grapevines. Exogenous ABA (50 μM) increased flavonoid content and endogenous ABA content by 74.03 % and 20.84 %, compared with alkali stress alone, respectively. Conversely, exogenous fluridone exacerbated alkali stress-induced physiological damage in grapevine plants. Transcriptome analysis revealed that exogenous ABA (50 μM) and fluridone significantly induced the ‘Plant hormone signal transduction (ko04075)’, the ‘MAPK signaling pathway-plant (ko04016)’, ‘ABC transporters (ko02010)’, ‘Photosynthesis-antenna proteins (ko00196)’, ‘Flavonoid biosynthesis (ko00941)’, ‘Phenylpropanoid biosynthesis (ko00940)’ and other biological pathways and key gene involved in chlorophyll metabolism and ion transport. In conclusion, ABA markedly enhanced grapevines tolerance to alkali stress by modulating key biological pathways and physiological characteristics.

Analysis of Bioactive Components of Pakcoy Microgreens (Brassica rapa L.) on Variations of Planting Media

Microgreens are new foods with bioactive compounds that are beneficial for human health. Microgreens Brassica rapa L. are small-scale, naturally occurring vegetable crops that possess a high antioxidant value and natural nutrient density.The profile of bioactive compounds is influenced by variations in growing media on microgreens Brassica rapa L. including rice husk charcoal, cocopeat, and top soil.The purpose of this study was to analyze the increase in flavonoid, chlorophyll and carotenoid compounds in several variations of growing media: This research was conducted using a Non-Factorial Randomized Group Design (RAK) with three treatment levels, namely top soil, top soil + rice husk charcoal, top soil + cocopeat with five replications. Parameters measured were flavonoid compounds, chlorophyll a b, and carotenoids. Results: the analysis showed that the best planting media were rice husk charcoal, cocopeat, and top soil, respectively had a significant effect on the increase in Chlorophyll (42.12 mg L-1) and Carotenoids (10.63 µmol/L) Flavonoids (19.19 µmol g-1). Conclusion: The best recommended planting medium is rice husk charcoal which shows a significant effect on increasing Chlorophyll (42.12 mg L-1) Carotenoids (10.63 µmol/L) and cocopeat which shows a significant effect on increasing flavonoid content (19.19 µmol g-1).

A novel MYB transcription factor from durian (Durio zibethinus), DzMYB1, regulates flavonoid biosynthesis in fruit pulp

Flavonoids are phenolic substances and exhibit strong antioxidant properties. The biosynthesis of flavonoids is regulated by various transcription factors (TFs), with MYB TFs playing a key role in controlling essential genes within this pathway. In this study, we identified candidate MYB TFs from our pulp transcriptome database of durian ‘Monthong’ cultivar. MYBs exhibiting upregulation during the ripe stage were considered transcriptional activators, due to their positive correlation with flavonoid gene expression and flavonoid accumulation in ripe durian pulps. One candidate MYB activator, DzMYB1, which was highly expressed at the ripe stage, was selected for functional characterization. Studies involving transient expression of DzMYB1 in Solanum lycopersicum cv. Micro-Tom fruit demonstrated increased flavonoid content, as analyzed by LC–MS/MS, compared with the GFP control. Moreover, we showed that DzMYB1 controls flavonoid biosynthesis by interacting with the promoters of various flavonoid biosynthetic genes, including chalcone synthase, chalcone isomerase, and flavanone 3-hydroxylase, resulting in their transcriptional activation. Additionally, we found that DzMYB1 functions as a homodimer and binds to a homodimerized DzbHLH1 in the intricate regulation of flavonoid biosynthesis. These findings provide comprehensive insights into the functional roles of MYB protein in the regulation of the flavonoid pathway within durian pulps.

Effect of Light Conditions, Trichoderma Fungi and Food Polymers on Growth and Profile of Biologically Active Compounds in Thymus vulgaris and Thymus serpyllum.

The research investigates the influence of different lighting conditions and soil treatments, in particular the application of food polymers separately and in combination with spores of Trichoderma consortium, on the growth and development of herbs-Thymus vulgaris and Thymus serpyllum. The metabolic analysis focuses on detecting changes in the levels of biologically active compounds such as chlorophyll a and b, anthocyanins, carotenoids, phenolic compounds (including flavonoids), terpenoids, and volatile organic compounds with potential health-promoting properties. By investigating these factors, the study aims to provide insights into how environmental conditions affect the growth and chemical composition of selected plants and to shed light on potential strategies for optimising the cultivation of these herbs for the improved quality and production of bioactive compounds. Under the influence of additional lighting, the growth of T. vulgaris and T. serpyllum seedlings was greatly accelerated, resulting in an increase in shoot biomass and length, and in the case of T. vulgaris, an increase in carotenoid and anthocyanin contents. Regarding secondary metabolites, the most pronounced changes were observed in total antioxidant capacity and flavonoid content, which increased significantly under the influence of additional lighting. The simultaneous or separate application of Trichoderma and food polymers resulted in an increase in flavonoid content in the leaves of both Thymus species. The increase in terpenoid content under supplemental light appears to be related to the presence of Trichoderma spores as well as food polymers added to the soil. However, the nature of these changes depends on the thyme species. Volatile compounds were analysed using an electronic nose (E-nose). Eight volatile compounds (VOCs) were tentatively identified in the vapours of T. vulgaris and T. serpyllum: α-pinene, myrcene, α-terpinene, γ-terpinene; 1,8-cineole (eucalyptol), thymol, carvacrol, and eugenol. Tendencies to increase the percentage of thymol and γ-terpinene under supplemental lighting were observed. The results also demonstrate a positive effect of food polymers and, to a lesser extent, Trichoderma fungi on the synthesis of VOCs with health-promoting properties. The effect of Trichoderma and food polymers on individual VOCs was positive in some cases for thymol and γ-terpinene.

Consecutive Pruning Enhances Leaf Flavonoids, Leaf Yield, and Cutting Rooting in Ginkgo biloba

Ginkgo biloba L. is a valuable medicinal plant known for its high content of flavonoids and terpenoids in the leaves of young trees. Pruning can increase leaf yield in ginkgo plantations; however, it is unclear how the intensity of pruning affects leaf yield and quality. In addition, G. biloba exhibits low cutting rooting rates, which limits its efficiency in asexual propagation. In our study, we compared consecutive pruning with varying levels of intensity, including top pruning, light pruning, and heavy pruning, to evaluate the effects of pruning on leaf yield and cutting rooting. The results showed that these three pruning methods all contributed to an increase in the number of new branches, the leaf weight, and the flavonoid content in five-year-old trees. Among them, the effect of light pruning was the best, with a 150% increase in branch number, a 130% increase in leaf weight, and a 40.6% increase in flavonoid content. The secondary pruning further increased leaf area by 22.3%, indicating that secondary pruning further enhanced the rejuvenation of plants and increased leaf yield. At the transcriptional level, pruning can significantly change the expression of genes related to bud sprouting, resulting in a particularly significant increase in SHR expression in the buds. Pruning also promoted the expression of important genes related to flavonoid synthesis, including chalcone synthase (CHS), flavonoid 3′-hydroxylase (F3′H), flavonol synthase (FLS), and dihydroflavonol reductase (DFR). Furthermore, we demonstrated a significant increase in the rooting rate of these second-pruned branch cuttings and screened the optimal hormone ratio for rooting, which is 1.5 μM MeJA + 400 mg/L NAA + 100 mg/L Uniconazole-P. These results suggest that secondary pruning can effectively rejuvenate plants to promote cutting rooting in G. biloba. This method can not only be used to improve the yield and quality of ginkgo leaves, but also for cutting propagation.

The Effect of Fermented Jicama Extract with Lactobacillus plantarum B1765 as the Culture Starter on the Product Quality and Flavonoid Contents

Jicama (Pachyrhizus erosus) is a functional food containing phenolic compounds, with the main compounds being flavonoids. However, the presence of polyphenol oxidase and the structure of flavonoid compounds are still bound in the form of glycosides, so the bioactivity of jicama is not maximized. This study aims to determine the effects of jicama extract fermentation on product quality and increased flavonoid content in jicama. Fermentation was performed for 0, 12, 24, and 36 hours with 5% (v/v) of the starter culture, Lactobacillus plantarum B1765, at 37ºC. The result showed that fermentation times could increase Total Lactic Acid Bacteria (LAB), Total Tertitrable Acid (TTA), Total Phenolic Content (TPC), and Total Flavonoid Content (TFC). It also influenced a decrease in pH. The total LAB count was determined using the Total Plate Count method, the Total Tertitrable Acid was determined using acid-base titration, and the pH was determined using a pH meter. Total Phenolic Content was measured using the Folin-Ciocalteu method, and Total Flavonoid Content was measured using AlCl3 and potassium acetate. The analysis of the data revealed that jicama extract fermented optimum after 24 hours, with a total LAB count of 9.7x107±0.31 CFU/mL, a pH value of 4.21±0.22, a TTA of 0.376±0.025%, but TPC and TFC still increasing until 24 hours of fermentation to 16.22±0.312 mg GAE/g, and of 29.01±0.641 mg QE/g respectively. Fermentation of jicama extract with Lactobacillus plantarum B1765 increased total phenolic and total flavonoid contents and could be used as a functional food product.

Growth and Phytochemistry of Cymbopogon citratus Stapf Inoculated with Plant Growth-Promoting Bacteria under Different Lead Levels.

This study aimed to investigate the phytochemistry of lemongrass (Cymbopogon citratus) inoculated with Azospirillum brasilense and grown in lead (Pb)-contaminated soil to assess its responses to inoculation under different Pb levels. The experimental design was completely randomized in a 2 × 5 factorial scheme: two levels of A. brasilense (absence or presence) and five Pb levels. After four months of treatment, the following were analyzed: total and reducing sugars, total phenolic content, flavonoids, antioxidant activity, antioxidant enzymes, proline, and essential oil (EO) content and composition. Soil Pb levels and A. brasilense inoculation affected phytochemicals in lemongrass plants. Azospirillum inoculation reduced total sugars in the roots at all soil Pb levels, while increasing Pb levels favored a rise in sugar contents. There was an increase in flavonoid content in treatments associated with Pb and inoculated with A. brasilense. Antioxidant capacity was lower at lower Pb levels, regardless of bacterial inoculation. Enzymatic response was mainly affected by Pb concentrations between 50 and 100 mg kg-1 soil. EO content was influenced by soil Pb levels, with higher EO production at 500 mg Pb kg-1 soil and without A. brasilense inoculation. Overall, lemongrass cultivation in Pb-contaminated areas can be an alternative to phytoremediation and EO production for the industry.

ДИНАМИКА НАКОПЛЕНИЯ САХАРОВ И ФЛАВОНОИДОВ В ЛИСТЬЯХ ГРУШИ ПРИ МОДЕЛИРОВАННОМ ОСМОТИЧЕСКОМ СТРЕССЕ

The purpose of the study is to conduct a comparative assessment of three pear varieties in terms of the content of soluble sugars and flavonoids under simulated osmotic stress. The objects of the study are three varieties of pear Pyrus communis L.: two varieties Williams and Conference of European origin and one domestic variety Flamenco selected by the North Caucasus Federal Scientific Center for Horticulture, Viticulture, and Winemaking. Drought was simulated in two ways. In the first case, the leaves were cut into leaf disks with a diameter of 1 cm, then immersed in a 20 % solution of polyethylene glycol (PEG-6000) for 2 hours at room temperature. Control is buffer solution not containing polyethylene glycol. The second method is to place pear shoots in a solution of 15 % sorbitol for a day at room temperature, where water was the control. Exposure to 15 % sorbitol caused more intense synthesis of primary and secondary metabolites compared to 20 % PEG solution. In July, an increase in the accumulation of sugars compared to the control was noted in the Conference variety (25.6 mg glucose equivalent/g fresh weight), in August this figure sharply increased in the Flamenco and Williams varieties to 24.3 and 25.7 mg equivalent. glucose/g wet weight, respectively. A significant increase in flavonoid content in response to sorbitol stress was detected in August for the Flamenco and Conference varieties, in which the average values changed from 2.1 and 2.5 to 3.6 and 4.2 mg/g fresh weight, respectively. Treatment of leaf disks with PEG did not initiate an increase in the synthesis of primary and secondary metabolites. A more effective way to create osmotic stress in the tissues of pear leaves was treatment with a sorbitol solution.

Enhancement of nutraceutical components of mushroom by uv exposure and extension of their shelf-life using edible coating material adopting online assessment of keeping quality by Magnetic Resonance Imaging (MRI) technique

To enhance the nutraceutical value and preservation of mushrooms, this study focused on augmenting two widely consumed mushroom varieties in India namely the Button Mushroom (Pleurotus ostreatus) and Oyster Mushroom (Agaricus bisporus). These mushrooms were subjected to UV light exposure to evaluate their impact on phytochemical content, including phenolics, flavonoids, folic acid, and Vitamin D2. The percent increase in phenolic content after 120 minutes of UV treatment was 0.6-fold for Agaricus bisporus and 0.7-fold for Pleurotus ostreatus. Notably, A. bisporus exhibited a particularly high phenolic content of up to 13.5 mg per gram dry weight of mushroom after 120 minutes of UV exposure, in contrast to P. ostreatus, which displayed 8.7 mg per gram dry weight of mushroom under the same conditions. This study also revealed a threefold increase in flavonoid content in Pleurotus ostreatus, rising from 1.2 mg of quercetin/g in the control to 4.1 mg of quercetin/g after UV exposure for 120 minutes. Conversely, a sevenfold increase in quercetin content was observed in Agaricus bisporus, surging from 0.45 g (control) to 3.2 g following 120 minutes of UV exposure. The exposure of UV light for 60 minutes resulted in the highest absorbance of vitamin D2 at 0.81 OD in Pleorotus osteatus compared to 0.46 in Agaricus bisporus. Additionally, applying agar or gelatine coatings led to a shelf-life extension of up to 14 days under standard storage conditions. The use of MRI for quality determination of mushrooms by evaluating the lipid profile in the samples was reported for the first time. This study has shown a significant enhancement of nutraceutical components of mushrooms with special reference to phenolics, flavonoids, folic acid, and vitamin D2 for value addition, with a simple intervention of UV treatment. Moreover, the shelf life of mushrooms could be enhanced by agar and gelatin coating thereby extending the keeping quality. The use of MRI for evaluating the quality of mushrooms has also been the hallmark of this study. The practical utility of all the above findings has immense industrial application in the large-scale production of highly nutritive mushrooms.

Molecular and metabolic insights into purplish leaf coloration through the investigation of two mulberry (Morus alba) genotypes

BackgroundLeaf coloration in plants, attributed to anthocyanin compounds, plays a crucial role in various physiological functions, and also for pharmaceutical and horticultural uses. However, the molecular mechanisms governing leaf coloration and the physiological significance of anthocyanins in leaves remain poorly understood.ResultsIn this study, we investigated leaf color variation in two closely related mulberry genotypes, one with purplish-red young leaves (EP) and another with normal leaf color (EW). We integrated transcriptomic and metabolomic approaches to gain insights into the metabolic and genetic basis of purplish-red leaf development in mulberry. Our results revealed that flavonoid biosynthesis, particularly the accumulation of delphinidin-3-O-glucoside, is a key determinant of leaf color. Additionally, the up-regulation of CHS genes and transcription factors, including MYB family members, likely contributes to the increased flavonoid content in purplish-red leaves.ConclusionThese findings enhance our understanding of the molecular mechanisms responsible for the purplish coloration observed in mulberry leaves and also offer supporting evidence for the hypothesis that anthocyanins serve a protective function in plant tissues until the processes of light absorption and carbon fixation reach maturity, thereby ensuring a balanced equilibrium between energy capture and utilization.