Flavonoid Compounds Research Articles

Influence of temperature, solvent and extraction procedure on the content of phenolic compounds and antioxidant activity of <i>Aloysia citriodora</i> Palau leaves

Introduction: The leaves of Aloysia citriodora Palau are a source of phenolic compounds that have antioxidant properties. Objective: The objective of this study was to compare the effects of temperature, type of solvent, maceration, and ultrasound processes in the extraction of phenolic compounds from A. citriodora Palau leaves that allow for maintaining the highest antioxidant capacity. Methods: In this study, phenolic compounds were extracted from A. citriodora by two methods, maceration, and ultrasonic treatment, using water and 80% ethanol as solvents and extraction temperatures of 25 °C, 45 °C, and 65 °C. Total phenolic compounds (TPhen), total flavonoid compounds (TFlav), and antioxidant capacity, evaluated by DPPH and ABTS assay, were characterized and reported as inhibition concentration (IC50). Results: The highest CPhen content was obtained with ethanolic extract using the ultrasonic method at 65 °C, with a value of 15.32 mg EAG/mL at 65 °C. For TFlav, the highest value was obtained with the ultrasonic treatment at 45 °C using ethanol as solvent, obtaining a value of 6.52 mg EQ/mL. The best antioxidant capacity was shown by the sonication with ethanol at 65 and 45 °C, with IC50 values of 27.10 µg/mL and 20.40 µg/mL, respectively. Conclusion: Ultrasound extraction at higher temperatures (45°C and 65°C) proved more effective than maceration, yielding greater amounts of phenolic and flavonoid compounds and exhibiting better antioxidant capacity.”. Keywords: Aloysia citrodora, phenolic compounds, antioxidant activity, inhibitory concentration IC50.

Anti- psoriatic effect and phytochemical evaluation of Iraqi Scabiosa palaestina ethyl acetate extract

The purpose of this study was to confirm the antipsoriasis activity of Scabiosa palaestina (S. palaestina) ariel component extract and identify the active compound(s) responsible for this activity using a developed RP-HPLC technology. The active ethyl acetate extract of S. palaestina was extracted and fractionated by the hot continuous Soxhlet apparatus method. Psoriasis was induced in experimental animals after 4 days of imiquimod (IMQ) cream application on dorsal skin rats of 3 treated groups (6 rats for each) and the normal group (6 rats) left without treatment. Two of the psoriatic-induced groups were treated with ethyl acetate (EA) extract or methotrexate (MTX) for 12 days, starting from day 4 of the IMQ application. Assessment of psoriatic lesions was done during the experiment, depending on the psoriasis area severity index (PASI). At the end of the study (day 15), animals were sacrificed and 2 skin specimens were collected for histopathological examination and cytokine measurement. Compared with the positive control group, ethyl acetate extract shows significant improvement in PASI (p-value < 0.05) and histopathological changes exerted by IMQ. On the other hand, no significant reduction has been seen in the psoriatic and angiogenic mediator (IL-17 and VEGF) with a P-value > 0.05 compared with the positive control group, which may be attributed to other cytokines that could be affected by the ethyl acetate extract of S. palaestina. These results suggest that the antipsoriasis properties of ethyl acetate extract may possibly be due to the presence of flavonoid compounds (luteolin, apigenin, quercetin, vitexin and kaempferol).

Fabrication of interfacial crystallized oleogel emulsion for quercetin delivery with enhanced environmental stability and bioaccessibility.

Quercetin is a flavonoid compound with numerous bioactivities. However, the low solubility, easy degradation and low bioaccessibility limit its application. In this study, a novel interfacial crystallized oleogel emulsion was fabricated, where beeswax was used as the oleogelator, for quercetin encapsulation with enhanced stability and bioaccessibility. The process of interfacial crystallization was investigated using interfacial rheology and polarized microscopy, with a positive correlation between crystal density and beeswax content in the oil phase. Emulsion stability was directly linked to beeswax concentration in the oil phase, with 100 mg g-1 showing enhanced stability under storage, UVB light exposure and ionic conditions. Beeswax addition significantly increased the quercetin loading capacity of the emulsion; particularly, at a 200 mg g-1 beeswax concentration, the loading capacity was improved by 285.55%, and the environmental stability was enhanced against UV light and Ca2+. Ultimately, in vitro simulated digestion experiment indicated improved bioaccessibility of quercetin. This strategy significantly enriched the formulation of oleogel emulsion and its potential applications in delivering bioactive ingredients with high environmental vulnerability. © 2024 Society of Chemical Industry.

Isolation of Flavonoid Compound from Kareumbi Fruit (Homalanthus populneus (Geiseler) Pax)

Flavonoid compounds were isolated from Kareumbi fruit (Homalanthus populneus) using a sequential extraction and purification process. Methanol-concentrated extract was partitioned with ethyl acetate and n-hexane. The concentrated methanol extract was separated by column chromatography using a gradient elution of chloroform and methanol, varying the ratio 90:10; 80:20; 70:30; and 60:40 (v/v). Subsequent column chromatography yielded a yellowish-orange paste (19.6 mg, Rf = 0.73) from the chloroform:methanol (70:30) fraction. UV-visible, FT-IR, and 1H-NMR spectroscopic analysis confirmed that the isolated compounds belonged to the flavonol class of flavonoids.

Luteolin inhibits orthodontic tooth movement and relapse

Luteolin is a natural flavonoid compound that widely exists in human food. Studies have demonstrated luteolin has powerful anti-inflammatory properties and can affect bone remodeling in an inflammatory environment. This study aimed to investigate the effect of luteolin on orthodontic tooth movement (OTM) and relapse after OTM. Male Sprague Dawley rats were randomly divided into 3 groups (n= 8): OTM, 50 mg/kg/d luteolin, and 100 mg/kg/d luteolin. Then, 50 g of orthodontic force was applied to all animals. A saline solution or corresponding concentration of luteolin was given orally. For the OTM experiment, after 14 days of force application, rats were killed, the maxilla was dissected, and then microcomputed tomography, histologic staining, and western blotting were performed. For the relapse experiment, the spring was removed, and a silicone impression was made to record the relapse status. Compared with the OTM alone group, systemic administration of luteolin inhibited OTM and tooth relapse (P<0.05). Increased bone volume, reduced osteoclast activity, and a decrease in osteoclastogenesis-related protein expression were observed in luteolin-treated groups. These effects may be attributed to the inhibition of the nuclear factor-kappa B pathway. Luteolin can significantly inhibit OTM and relapse after OTM. Thus, luteolin is a prospective candidate for enhancing tooth anchorage and preventing relapse in orthodontic treatment.

Selenium Nanoparticles Regulate Antioxidant Enzymes and Flavonoid Compounds in Fagopyrum dibotrys

Fagopyrum dibotrys is a herbal plant. Selenium (Se) is a beneficial element for plants; selenium nanoparticles (SeNPs) are gaining importance in food and agriculture due to their low toxicity and high activity. This study revealed that foliar application of SeNPs enhanced superoxide dismutase, glutathione peroxidase, and peroxisome activities and significantly enhanced the flavonoid compound content in F. dibotrys. SeNPs with a concentration of 5.0 mg L−1 also promoted the growth of F. dibotrys. The foliar application of SeNPs could be absorbed by pores in leaves of F. dibotrys and mainly transformed to selenomethionine (32.5–43.2%) and selenocysteine (23.4–38.4%) in leaves and tubers of F. dibotrys. Consequently, this study offers a profound understanding of plants’ uptake and biotransformation of SeNPs. Furthermore, the findings of this study have suggested that SeNPs can be applied to improve the quantity and quality of the herbal plant of F. dibotrys.

Flavonoids attenuate inflammation of HGF and HBMSC while modulating the osteogenic differentiation based on microfluidic chip

BackgroundWhen inflammation occurs in periodontal tissues, a dynamic cellular crosstalk interacts between gingival fibroblasts and bone marrow mesenchymal stem cells (BMSCs), which plays a crucial role in the biological behaviour and differentiation of the cells. Recently, flavonoids are increasingly recognized for their therapeutic potential in modulating inflammation and osteogenic differentiation. Owing to their varied molecular structures and mechanisms, there are more needs that flavonoid compounds should be identified by extensive screening. However, current drug research mostly relies on static, single-type cell cultures. In this study, an innovative bionic microfluidic chip system tailored for both soft and hard tissues was developed to screen for flavonoids suitable for treating periodontitis.MethodsThis study developed a microfluidic system that bionically simulates the soft and hard structures of periodontal tissues. Live/dead staining, reactive oxygen species (ROS) staining, and RT-qPCR analysis were employed. These techniques evaluated the effects of flavonoid compounds on the levels of inflammatory factors and ROS contents in HGF and HBMSC under LPS stimulation. Additionally, the impact of these compounds on osteogenic induction in HBMSC and the exploration of the underlying mechanisms were assessed.ResultsThe microfluidic chip used in this study features dual chambers separated by a porous membrane, allowing cellular signal communication via bioactive factors secreted by cells in both layers under perfusion. The inflammatory response within the chip under LPS stimulation was lower compared to individual static cultures of HGF and HBMSC. The selected flavonoids-myricetin, catechin, and quercetin-significantly reduced cellular inflammation, decreased ROS levels, and enhanced osteogenic differentiation of BMSCs. Additionally, fisetin, silybin, and icariside II also demonstrated favorable outcomes in reducing inflammation, lowering ROS levels, and promoting osteogenic differentiation through the Wnt/β-catenin pathway.ConclusionsThe bionic microfluidic chip system provides enhanced capabilities for drug screening and evaluation, delivering a more precise assessment of drug efficacy and safety compared to traditional in vitro methods. This study demonstrates the efficacy of flavonoids in influencing osteogenic processes in BMSCs primarily through the Wnt/β-catenin pathway. These results uncover the potential of flavonoids as therapeutic medicine for treating periodontitis, meriting further research and development.Graphical

Spirulina Unleashed: A Pancreatic Symphony to Restore Glycemic Balance and Improve Hyperlipidemia and Antioxidant Properties by Transcriptional Modulation of Genes in a Rat Model

Hyperlipidemia is the root cause of numerous chronic conditions, leading to high mortality rates around the globe. Spirulina (Arthrospira platensis) microalgae serve as a promising reservoir of bioactive compounds with diverse pharmacological properties. The current study examined the nutritional profile of spirulina powder in relation to strict glycemic control, specifically focusing on its potential to lower lipid levels. In an in vivo investigation, normal healthy male Wistar albino rats (n = 60) were divided into two groups: a negative control group (NC) of ten rats and a high-fat diet group (n = 50) that were fed a cholesterol-rich diet until their cholesterol levels reached or exceeded 250 mg/dL. Subsequently, the hypercholesterolemic rats were then randomly allocated to several treatment groups: a positive control (PC); a standard treatment diet (STD) involving fenofibrate at a dose of 20 mg/kg body weight; and three experimental groups (T1, T2, and T3) that received spirulina powder supplementation at doses of 300, 600, and 900 mg per kg body weight, respectively, for the period of 12 weeks. Blood samples were analyzed for oxidative stress biomarkers, insulin levels, lipid profiles, liver function, and expression of gene levels in the diabetogenic pathway. The study utilized spectrophotometric colorimetric methods to identify oxidative stress biomarkers, serum kit methods to measure lipid profiles and liver enzymes, and the assessment of qPCR for mRNA quantity. According to the research findings, spirulina powder has certain noteworthy features. It had the greatest quantity of chlorogenic acid (4052.90 µg/g) among seven phenolics and two flavonoid compounds obtained by HPLC-UV analysis. Furthermore, the proximate analysis demonstrated that spirulina is high in protein (16.45 ± 0.8%) and has a significant energy yield of 269.51 K-calories per 100 g. A maximal spirulina dose of 900 mg/kg/wt significantly lowered oxidative stress, cholesterol, triglyceride, low-density lipoproteins (LDL), and insulin levels (p ≤ 0.05). In contrast, high-density lipoprotein (HDL) and total antioxidant capacity (TAC) levels increased significantly (p ≤ 0.05) compared to all other groups, except the NC group. The study provides remarkable proof about the pharmacological impact of spirulina powders. Significant reductions (p ≤ 0.05) in liver enzymes {alanine aminotransferase (ALT) and aspartate aminotransferase (AST)} were observed across all treatment groups, with the exception of the NC, compared to the positive control. The treatment groups had significantly greater gene expression levels of INS-1, PDX-1, IGF-1, and GLUT-2 than the positive control group (p ≤ 0.05). These findings highlight spirulina’s potential as a long-term regulator of hyperglycemia in rat models with induced hyperlipidemia, owing to its phenolic bioactive components that serve as antioxidants.

Caenorhabditis elegans as an Outstanding Model to Explore Flavonoids Under Stress Conditions

Abstract: Plants produce promising chemicals called secondary metabolites in response to stress, which protect against oxidative damage in both plants and humans. Reactive oxygen species (ROS) levels combined with an imbalance in the antioxidant responses can trigger oxidative stress that is related to many conditions such as Alzheimer's disease, diabetes, and cancer. One way to counteract or avoid the stress excess is by flavonoid administration, a class of plant metabolites with a consistent antioxidant action and the ability to inactivate the free radical excess. The mechanisms, as well as the benefits and toxicity of antioxidant products, can be tested in alternative animal models. The mechanisms, as well as the benefits and toxicity of antioxidant products, can be tested in alternative animal models. In this review, we explored how Caenorhabditis elegans, a nematode with high genetic similarity to human genes and the antioxidant response pathway conserved, can be considered an attractive model organism for testing flavonoid compounds. Here, we emphasize the crucial results regarding C. elegans and the flavonoid quercetin, focusing on oxidative stress and aging investigations. Also, this review highlights the quercetin benefits in C. elegans lifespan, healthspan, neurodegeneration, and impacts on insulin/IGF-1 signaling (IIS).

UNDERSTANDING THE BENEFITS OF STEVIA REBAUDIANA BERTONI FOR DIABETES: A COMPREHENSIVE REVIEW

Diabetes Mellitus (DM) is a complicated metabolic condition defined by long-term elevated blood glucose levels. This chronic hyperglycemia induces metabolic dysfunctions that cause structural and functional disruptions in the vasculature, leading to macrovascular and microvascular complications. Stevia rebaudiana Bertoni, commonly known as Stevia, is a perennial shrub that contains various bioactive constituents responsible for its sweetness and several other activities. Many studies on Stevia have shown that it possesses various beneficial effects on health, including being zero-calorie, anti-obesity, anti-diabetic, anti-hypertensive, antioxidant, antimicrobial and anti-tumor. Several studies have found that neither gastric juice nor digestive enzymes decompose stevioside. The presence of bioactive phenolic and flavonoid compounds supports Stevia's medicinal properties and its potential use in both the food/nutraceutical and pharmaceutical industries. A significant antioxidant capacity of Stevia has been identified recently. It can also help limit essential nutrient supply to tumor cells. Research on Stevia's effects on the human body has largely found no negative side effects. The growing body of evidence underscores Stevia's potential role in managing various health conditions, particularly for diabetic patients, due to its minimal impact on blood sugar levels. However, to fully harness its benefits and meet the increasing global demand, further scientific research is essential to optimize its cultivation, enhance its chemical constituents and ensure its safety. Overall, Stevia stands out as a promising natural sweetener with significant health benefits for diabetic patients. In this review article, we explore different aspects of Stevia and its beneficial effects on diabetic patients.

Isoliquiritigenin alleviates SLC7A11-mediated efferocytosis inhibition to promote wounds healing in diabetes

The healing process of chronic wounds often progresses slowly and is fraught with challenges, imposing increasing economic burdens and physical suffering on patients. Managing persistent wound inflammation and stimulating angiogenesis are crucial elements in promoting wound healing. Plants have been playing a key role in traditional medicine, and their abundant bioactive components continually inspire the development and innovation of new drugs. Isoliquiritigenin (ISL), a flavonoid compound derived from licorice roots known as chalcone, has demonstrated multifaceted pharmacological potential. However, its effects on diabetic wounds and the detailed mechanisms remain to be investigated. Through in-depth exploration using network pharmacology, we successfully predicted potential therapeutic targets of ISL for ischemic diseases. The revealed mechanisms primarily focused on the critical pathway of efferocytosis. Subsequent in vivo experiments demonstrated that ISL significantly enhanced the efferocytosis of dendritic cells (DC), improving the functional behaviors of endothelial cells. Further research indicated that ISL promoted DC efferocytosis by regulating SLC7A11-mediated glycolysis. Notably, the overexpression of SLC7A11 diminished the positive effects of ISL, suggesting a potential antagonistic role of SLC7A11 in the regulatory process. In the wounds of diabetic mice, we observed that ISL accelerated DC efferocytosis and angiogenesis, resulting in faster wound closure and better tissue repair. In summary, this study not only demonstrates the broad potential of ISL in managing diabetic wounds but also delves deeply into its mechanisms, laying a solid theoretical foundation for future clinical applications.

Luteolin prevents cadmium-induced PC12 cell death by suppressing the Akt/mTOR signaling pathway.

Cadmium (Cd) is an environmental pollutant that can cause neurodegenerative disorders. Luteolin (Lut) is a natural flavonoid compound. However, whether Lut protects against Cd-induced nerve cell death remains unclear. In the present study, PC12 cells were used to investigate the neuroprotective effect of Lut against Cd poisoning. Changes in cell viability, apoptosis, B-cell lymphoma-2 (Bcl-2) and Bcl-2-associated X protein expression, and protein kinase B (Akt)/mammalian target of rapamycin (mTOR) pathway activity were analyzed by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, Hoechst 33258 staining, flow cytometry, and western blotting. Lut markedly attenuated the Cd-induced reduction in cell viability, nuclear fragmentation, condensation, and the decrease in the Bcl-2/Bcl-2-associated X protein ratio in PC12 cells. Furthermore, Lut blocked the Cd-mediated activation of the Akt/mTOR signaling pathway. Moreover, inhibition of the Akt/mTOR signaling pathway with LY294002 (a PI3K inhibitor) enhanced the protective effect of Lut against Cd-induced cell death by suppressing Cd-induced activation of Akt, mTOR, and eukaryotic initiation factor 4E binding protein 1. The results showed that Lut prevented Cd-induced cell death partly by blocking the Akt/mTOR signaling pathway. Lut may be a potential agent for preventing Cd-induced nerve cell damage and neurodegenerative diseases.

Formulasi dan Evaluasi Ekstrak Aseton Kulit Putih Semangka Merah Non Biji (Citrullus Vulgaris S) dengan Niacinamide sebagai Gel Pelembab Kulit dengan Uji Kelembapan

This research was carried out with the aim of identifying the content of phytochemical compounds of alkaloids, flavonoids, tannins and saponins in the acetone extract of seedless red watermelon rind (Citrullus vulgaris), knowing the results of evaluating the physical properties of the acetone extract gel of seedless red watermelon rind (Citrullus vulgaris) with niacinamide against various concentrations of moisturizing gel preparations, and comparing the best moisture test concentration on acetone extract gel preparations of seedless red watermelon rind (Citrullus vulgaris) in providing optimal results. This research is a laboratory study of the experimental formulation of acetone extract of seedless red watermelon rind (Citrullus vulgaris) to determine the formulation and concentration of the best extract produced. The research results showed that acetone extract from the white skin of red seedless watermelon (Citrullus vulgaris) contained phytochemical compounds alkaloids, flavonoids, and polyphenol as well as lycopene in the white skin of red seedless watermelon (Citrullus vulgaris). The results of the evaluation of the physical properties of the acetone extract gel of seedless red watermelon rind (Citrullus vulgaris) in the negative control, 2.5% concentration, 5% concentration, and 7.5% concentration met the test requirements but did not meet the spreadability test requirements. And the best concentration of water content test in the acetone extract gel preparation of seedless red watermelon rind (Citrullus vulgaris) in providing optimal results is found in the gel preparation with a concentration of 7.5%.

Investigating Flavonoids by HPTLC Analysis Using Aluminium Chloride as Derivatization Reagent

This is the first study to report on high performance thin layer chromatography (HPTLC) generated spectrophotometric data to systematically capture flavonoid compounds using optimized derivatization with either AlCl3 or NaNO2-AlCl3-NaOH as visualisation reagents. While the traditional AlCl3 colorimetric method using UV–Vis analysis provides valuable insights into the presence of flavonoids and allows derivation of the total flavonoid content (TFC) of a sample, HPTLC fingerprints obtained after spraying with AlCl3 or NaNO2-AlCl3-NaOH enable the visualization of the various flavonoids present in a sample based on their respective absorption shifts, thus complementing the traditional TFC assay. In this study, 40 different flavonoids representing different classes (flavonols, flavanolols, flavan-3-ol, flavones, flavanones, and isoflavonoids) were analysed. Upon derivatization with AlCl3 most of the investigated flavonoids recorded bathochromic shifts, yielding characteristic λmax values between 370 and 420 nm, while spraying with NaNO2-AlCl3-NaOH triggered hyperchromic shifts, and thus an increase in absorbance intensity in flavonoids with particular substitution patterns. A few non-flavonoid components with structural similarities to flavonoids (e.g., rosmarinic acid, gallic acid, aspirin, salicylic acid) served as the negative control in this study to determine whether the derivatization reagents allowed exclusive detection of flavonoids. The method was then applied to the analysis of flavonoid containing supplements as well as red clover honey to demonstrate the method’s application in the analysis of natural products.

Determination of Total Flavonoid Content from Extract and Fractions of Mangrove Leaves (Rhizopora mucronata)

Indonesia is an archipelagic country with a very wide coastal area. Lombok Island has a coastal area with quite extensive mangrove forest areas. Rhizopora mucronata was the most dominant species found in the region. The Rhizopora mucronata species was a plant from the Rhizoporaceae family reported to have antibacterial, antifungal, and antioxidant activity. These biological activities were caused by the presence of secondary metabolite compounds in R. mucronata, one of which is flavonoids. Research regarding the flavonoid content of R. mucronata leaves has not been explored. Therefore, the study aimed to determine the total flavonoid content in extracts and fractions of R. mucronata leaves using the spectrophotometric UV-Vis method. R. mucronata mangrove leaves simplicia were extracted using the sonication method using 96% ethanol solvent, then fractionated using the liquid-liquid extraction method with n-hexane, ethyl acetate, and water. The percentage yield of 96% ethanol extract, water fraction, ethyl acetate fraction, and n-hexane fraction respectively were 42.33%; 43.147%; 40.49%; 9.74%; and 32.49%. The TLC test showed the presence of flavonoid compounds detected in the extract and fractions which were marked with blue spots. The total flavonoid contents in the 96% ethanol extract, water fraction, ethyl acetate fraction, and n-hexane fraction were respectively (12,980; 14,160; 23,880; and 25,350) mg Quercetin equivalent/gram sample (mg QE/ g). The total flavonoid content of the extract and fractions of R. mucronata leaves were analyzed using the One-way ANOVA test method. The total flavonoid content in the n-hexane fraction and ethyl acetate fraction was significantly higher than the 96% ethanol extract and water fraction. The total flavonoid content of R. mucronata leaves was relatively high, which contributes to several of its biological activities.

Activities of Chalcone Derivatives from Boesenbergia rotunda Against Human Estrogen Receptor Alpha of Breast Cancer by In Silico

The high prevalence of cancer must be overcome with prompt and appropriate prevention and treatment. New drug design is an effort to develop existing drugs, and their molecular structure and biological activity have been known through structural modification. It encourages researchers to explore Indonesia's natural resources, especially plants with anticancer activity, namely by synthesizing chalcone-derived compounds derived from the isolation of Fingerroot rhizomes (Boesenbergia rotunda). The most common flavonoid compound found in rhizomes fingerroot plants is pinostrobin. Pinostrobin compounds and their derivatives are synthesized, resulting in chalcone compounds and their derivative modifications. The author conducted an in-silico test on pinostrobin compounds and 19 of their derivatives, chalcone compounds, and 18 derivatives using estrogenic-a receptors with PDB codes 3ERD and 1G50. The author hoped that from this silico test, compounds with more potential as anticancer for breast cancer would be obtained based on the results of docking with 3ERD and 1G50 receptors and can then be synthesized. In the results of this study, the compounds Bis-4-bromobenzyoxychalcone and Bis-4-chlorobenzyloxychalcone are the most appropriate compounds to be synthesized. It is hoped that in the future, they can be continued with activity tests of these compounds, both in vitro and in vivo, because these compounds are predicted to have the best activity and do not have hepatotoxic or other toxicity effects

VviMYB24 positively regulates flavonol biosynthesis in response to moderate drought stress in ‘Cabernet Sauvignon’ grape seedlings

Drought is a kind of adversity that has always severely restricted the growth of grapes. Flavonols, as flavonoid compounds, are abundant in grapes and have an indispensable function in resisting drought. Hereafter, the objectives of this investigation were to identify key drought-induced transcription factors in grape and explore their roles and regulatory networks in the flavonol-mediated drought response mechanism. In this study, one-year-old cutting seedlings of ‘Cabernet Sauvignon’ grape were used as experimental materials, cultivated in a solar greenhouse, and subjected to moderate drought treatment. The physiological and biochemical parameters related to stress and flavonol content in plant tissues were determined, and gene expression, functional validation, and transcriptional regulation relationships were explored. The results showed that the growth of grape plants was affected under drought conditions, the flavonol accumulation and the expression level of VviMYB24 were significantly induced by drought stress. Overexpression of VviMYB24 reduced the degree of cytoplasmic membrane damage and induced flavonol biosynthesis to confer drought tolerance in Arabidopsis plants and grape callus. Further study revealed that VviMYB24 can interact with the bHLH transcription factor VviMYC2b, which was positively responsive to drought, and they could activate VviFLS5 expression individually and/or in combination in the form of a complex. Interestingly, VviMYB24 could positively regulate VviMYC2b expression to form a transcriptional cascade, enhancing the function of the complex. Transient overexpression of VviMYB24, VviMYC2b, and VviFLS5 in grape leaves promoted the drought-responsive flavonol accumulation. Overall, the above data elucidated that the VviMYB24-VviMYC2b-VviFLS5 module positively regulates drought-induced flavonol biosynthesis in response to drought stress in grape, which contributes to further grape drought resistant breeding and variety improvement through biotechnology.

Combined Transcriptome and Metabolome Analyses Provide New Insights into the Changes in the Flesh Color of Anthocyanins in Strawberry (Fragaria × ananassa (Weston) Duchesne ex Rozier)

Background: Strawberries are bright in color, sweet and sour in taste, and rich in nutrients and flavonoid compounds such as anthocyanins and proanthocyanidins. The synthesis and accumulation of anthocyanins are the decisive factors that make strawberries appear bright red. From the perspective of plant breeding, a change in flesh color is an important goal. Methods: In this study, two strawberry plants with different flesh colors were selected, and transcriptome and metabolome analyses were performed during the color change period (S1) and ripening period (S2). Results: RNA-seq revealed a total of 13,341 differentially expressed genes (DEGs) between and within materials, which were clustered into 5 clusters. A total of 695 metabolites were detected via metabolome analysis, and 243 differentially regulated metabolites (DRMs) were identified. The anthocyanin biosynthesis, starch and sucrose metabolism and glycolysis/gluconeogenesis pathways were determined to be important regulatory pathways for changes in strawberry flesh color through a joint analysis of RNA-seq data and the metabolome. The leucoanthocyanidin reductase (LAR) and chalcone synthase (CHS) gene is a key gene related to anthocyanins, cinnamic acid, and phenylalanine. In addition, through joint RNA-seq and metabolome analyses combined with weighted gene co-expression network analysis (WGCNA), we identified 9 candidate genes related to strawberry flesh color. Conclusions: Our research findings have laid the groundwork for a more comprehensive understanding of the molecular mechanisms governing the color transformation in strawberry flesh. Additionally, we have identified novel genetic resources that can be instrumental in advancing research related to strawberry color change.

Application of Dietary Anthocyanins in Type 2 Diabetes Mellitus Treatment

Type 2 diabetes mellitus (T2DM) is a common metabolic disorder characterized by impaired glucose control around the world that causes huge health challenges globally with increased morbidity and mortality. Inadequate insulin secretion and decreased insulin sensitivity are considered as main contributors to T2DM. Anthocyanin, a type of flavonoid compound, is one potentially feasible dietary intervention for T2DM treatment in addition to clinical drug interference. Dietary anthocyanins can be found in various berries, vegetables, and beverages, which provide vibrant colors. Anthocyanins are also increasingly used as colorants in the food industry. It is also seen as a supplement because of its antioxidation properties. Meanwhile, several evidence demonstrate the potential relationship between dietary anthocyanin intake and T2DM management. In this work, recent epidemiologic studies on the potential effects of anthocyanins in controlling T2DM have been reviewed, especially focusing on the typical indexes such as glycemic levels, insulin levels, etc. Many studies illustrate that appropriate intake of dietary anthocyanins could control glycemic levels, adjust insulin levels, and reduce insulin resistance. Because of these functions, dietary anthocyanins may trigger positive effects on T2DM treatment. Dietary anthocyanins could be seen as a good dietary intervention in T2DM control that meets the requirement of long-term management for the specific chronic disease.

Investigation of antibacterial and anticancer activities of biosynthesized metal-doped and undoped zinc oxide nanoparticles.

Over the past 10 years, nanotechnology has emerged as a very promising technique for a wide range of biomedical applications. Green synthesized metal and metal oxide nanoparticles (NPs) are cheap, easy to produce in large quantities, and safe for the environment. Currently, efforts are being made to dope ZnO in order to improve its optical, electrical, and ferromagnetic qualities as well as its crystallographic quality. Actually, doping is one of the simplest methods for enhancing an NP's physicochemical characteristics because it involves introducing impure ions into the crystal lattice of the particle. In this study, the biosynthesis of zinc oxide NPs (ZnONPs) and metal-doped (Mg2+ and Ag+) ZnONPs was carried out by using aqueous and water-alcoholic extracts of Cynara scolymus L. leaves, Carthamus tinctorius L. flowers, and Rheum ribes L. (RrL) plant, which are rich in phytochemical content. Plant extracts act as a natural reducing, capping, and stabilizing agent in the production. The produced NPs were characterized using a variety of methods, such as ultraviolet-visible spectroscopy, Fourier transform infrared (FTIR) spectroscopy, dynamic light scattering (DLS), and scanning electron microscopy (SEM). The produced metal-doped and undoped ZnONPs exhibited characteristic absorption peaks between 365 and 383nm due to their surface plasmon resonance bands. SEM analysis revealed that the NPs were oval, nearly spherical, and spherical. In the FTIR spectra, the Zn-O bonding peak ranges from 400 to 700cm-1. The peaks obtained in the range of 407-562cm-1 clearly represent the Zn-O bond. In addition, the FTIR results showed that there were notable amounts of phenol and flavonoid compounds in both the prepared extract and ZnONPs. According to DLS analysis results, the size distribution of produced NPs is between 120 and 786nm. The antibacterial properties of green produced NPs on Gram-positive (Staphylococcus aureus RN4220) and Gram-negative (Escherichia coli DH10B) bacterial strains were investigated by agar well diffusion method. In studies investigating the anticancer activities of biosynthesized NPs, mouse fibroblast cells (L929) were used as healthy cells and human cervical cancer cells (HeLa) were used as cancer cells. Only the produced Ag-ZnONPs showed potent dose-dependent antibacterial activity (at concentrations higher than 100µg/mL) against Gram-positive and Gram-negative bacteria. RrL-ZnONP-600 and RrL-ZnONP-800 NPs produced with water-ethanol extract of RrL plant and calcined at 600 and 800°C were effective at high concentrations in healthy cells and at low concentrations in HeLa cancer cells, showing that they have the potential to be anticancer agents. The study's findings highlight the potential of green synthesis techniques in the production of medicinal nanomaterials for the treatment of cancer and other biological uses.