Glycoside Content Research Articles

Evaluation of Bioactive Compounds and Chemical Elements in Herbs: Effectiveness of Choline Chloride-Based Deep Eutectic Solvents in Ultrasound-Assisted Extraction.

In this study, the effectiveness of three choline chloride (ChCl)-based deep eutectic solvents (DESs) formed using malonic acid (MalA), glycerol (Gly), and glucose (Glu) as hydrogen bond donors and two conventional solvents (50% methanol and 50% ethanol) for ultrasonic-assisted extraction (UAE) of antioxidant compounds from four herbs (chamomile, lemon balm, nettle, and spearmint) were estimated. The antioxidant capacity (AC) of the obtained herb extracts was determined by the modified 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), 2,2-diphenyl-1-picrylhydrazyl (DPPH), and cupric reducing antioxidant capacity (CUPRAC) methods. Profiles of phenolic acids, flavonoid aglycones, and flavonoid glycosides in the green and conventional herb extracts were quantitatively analyzed using ultra-performance liquid chromatography (UPLC). Among the prepared DESs, the highest antioxidant potential and total contents of phenolic acids, flavonoid aglycones, and flavonoid glycosides in herb extracts were achieved using ChCl:MalA (1:1). Unexpectedly, the selected green solvents extracted significantly lower amounts of total antioxidants from the investigated herbs than 50% alcohols. Additionally, macroelements (K, Na, Ca, Mg), micronutrients (Mn, Zn, Fe, Cu), and a toxic element (Cd) in four herbs were analyzed using inductively coupled plasma-mass spectrometry (ICP-MS). Determining the compositions of antioxidants and elements in herbs is essential for understanding their nutritive importance when applied in the food, cosmetic, and pharmaceutical industries.

Bottle Aging of Smoke-Affected Wines: Changes in Smoke Flavor and Chemical Composition.

Winegrapes exposed to environmental wildfire smoke during ripening can be identified through analysis of volatile phenols and phenolic glycosides. While elevated concentrations of these smoke marker compounds in grapes have been shown to be predictive of composition and smoke flavor in young wines, recent research has demonstrated that not every wine produced from smoke-exposed grapes will inevitably have discernible smoke flavor when assessed as young wine 6 weeks after bottling. This is supported by anecdotal reports from wine producers that wines that do not appear noticeably smoky when young become noticeably smoky during aging. Yet there is little data available to date on the chemical composition and sensory attributes of aged wines produced from grapes exposed to environmental wildfire smoke. Data are largely limited to smoke-affected wines from model studies with deliberately smoked vines, and suggest that the concentrations of volatile phenols and glycosides may remain relatively unchanged after 5 to 6 years of bottle aging. To address the gap in knowledge, this study followed 49 wines made from grapes exposed to wildfire smoke during the 2019-2020 ripening season and reports the results obtained from monitoring chemical composition and smoke flavor intensity up for to three years after bottling. Notably, the concentrations of volatile phenols and glycosides did not change significantly over 39 months in the bottle, with the exception of syringol, which increased in both smoke-affected and control wines. Significant smoke flavor ratings were consistent over the three years for the majority of the wines (73%). For nine mildly smoke-affected wines, smoke flavor became apparent in older wines, while it had not been apparent in the young wines, likely due to masking by other attributes. These data represent a substantial database of smoke marker concentrations in wine and smoke flavor to provide context when interpreting smoke marker analysis in the future.

ISOLATION AND IDENTIFICATION OF ALLELOPATHIC COMPOUNDS FROM THE RESIDUES OF SOME SUNFLOWER CULTIVARS USING HPLC TECHNOLOGY

This research was conducted to detect some of the allelopathic chemical class in plant residues of nine cultivars of sunflower, including Zahret Al-Iraq, Luleo, Turkie, Al-Isaqi 1, Al-Isaqi 2, Tarzan, Akmar, Shumoos, and Sin Al-Theeb, using appropriate chemical reagents. Some of these chemical were furthered analysed for their content of allelopathic comopounds using High-Performance Liquid Chromatography (HPLC). Results revealed the presence of glycosides, alkaloids, tannins, terpenes, steroids and flavonoids the plant residues of the test sunflower cultivars. Concentrations of glycosides, tannins, alkaloids, and flavonoids were measured, were found to be highter in Shumoos and Tarzan 1018 cultivar residues. The analysis with the High-Performance Liquid Chromatography (HPLC) indicated the presence of several allelopathic compounds of phenolic in nature in the different sunflower cultivar residues, namely Rutin, Vanillin, Resorcinol, and Quercetin.

Membrane-Bound Bisindolyl-Based Chromogenic Probes: Analysis of Cyanogenic Glycosides in Agricultural Crops for Possible Remediation.

Cyanogenic glycosides are plant-derived, nitrogen-containing secondary metabolites that release toxic cyanide ions upon hydrolysis by glycosidic enzymes. Therefore, consuming food items enriched with such compounds without proper remediation can cause acute cyanide intoxication. Thus, in this work, we utilize cyanide-responsive oxidized bisindole-based chromogenic probes to detect cyanogenic glycosides, such as amygdalin and linamarin (LOD: 0.12 μM), in phospholipid membranes. The bilayer surface, owing to its distinct microenvironment, enhances both the sensitivity and specificity of the probes toward amygdalin. The chromogenic response (red to yellow) is influenced by the nature of the lipid membrane (order, polarity, and interfacial hydration) as well as the number of bis-indolyl units in the probe molecules. Semiquantitative analysis of food samples before and after cooking revealed that soaking in water at room temperature significantly reduces the cyanogenic glycoside content. The ability to directly detect cyanogenic glycosides in food samples without pretreatment is a notable aspect of this investigation.

The effect of supplemental LED lighting in the range of UV, blue, and red wavelengths at different ratios on the accumulation of phenolic compounds in pak choi and swiss chard

Phenolic compounds are known for their health-promoting effects on humans. Pak choi (Brassica rapa ssp. chinensis) and Swiss chard (Beta vulgaris subsp. vulgaris) are used here as model plants, as they are eaten raw as baby leaf lettuce and differ in their phenolic compound profile while showing similar morphology. In a greenhouse an artificial light source with UV-B (215 mW m−2), blue (104 μmol/m−2 s−1) and red (245 μmol/m−2 s−1) LEDs was implemented to increase phenolic compounds during the last days before harvest. Pak choi shows an increase or trend towards an increase in the monoacylated triglycosides of kaempferol and quercetin after 4 days of irradiation for 4 h each. For example kaempferol-3-caffeoyl-sophoroside-7-glucoside was increased at low PAR values in the third run and red-dominated light treatment by up to 120 %. In addition, it was observed that the red variety ‘Amur’ has higher concentrations of quercetin glycosides which were increased often. In swiss chard, on the other hand, there was only a sporadic increase in vitexin glycosides. Despite very different concentrations in some samples, 2″-glucosyl-vitexin and 2′′-glucosyl-6′′-malonyl-vitexin showed significant increases of up to 350 % in the two chard varieties Lukullus and Rhubarb chard. The results suggest that the exposure time or intensity of UV-B radiation needs to be optimized for each species and has not yet consistently led to an increase but trends in phenolic compounds and in antioxidant activity in this study.

Enhanced Growth Performance and Steviol Glycosides Content in Stevia Rebaudiana Under Elevated Carbon Dioxide

In the current climate-changing scenario with a steadily rising CO2 concentration, there is a chance that crop performance will be affected in terms of growth, yield, and quality. Therefore, an experiment was conducted in a glasshouse using a randomized complete block design with four replications to investigate the effect of short and long-term elevated CO2 on growth performance and chemical markers of Stevia rebaudiana Bertoni. The CO2 in the glasshouse was gradually elevated from 400 ppm to 1800 ppm weekly. The plants were exposed to elevated CO2 for four months (T1), two months (T2), and one month (T3), while the control plants (T4) were grown under ambient CO2 (aCO2) levels to assess the effect of elevated atmospheric carbon dioxide (eCO2) on stevia crop growth performance and steviol glycosides content. The number of branches per plant, plant height, number of leaves per branch, and plant biomass were found to be significantly increased under eCO2 treatment over aCO2 treatment. The eCO2 increased photosynthetic rate by 46% for T1, 45% for T2, and 29% for T3 over control plants (T4) at 3rd month of planting. The enhancement in photosynthesis is attributed to an increase in stevioside; with a 33% increase for T1 28.83% for T2 and 11% for T3 over aCO2. Similarly, the rebaudiosides A were also significantly increased by 32.8% for T1, 25% for T2, and 15% for T3 compared to the control under aCO2. Based on our findings, we concluded that eCO2 levels positively influenced the growth, biomass, and glycoside content by enhancing the physiological performance of Stevia rebaudiana Bertoni.

Determination of the Content of Hairy Vetch Isoflavone Glucoside in Qianliekang Tablets

Objective: To determine the content of maohui isoflavone glycoside based on its composition in Qianliekang tablets. Methods: High-Performance Liquid Chromatography (HPLC) was employed for the determination, with a detection wavelength set at 260 nm; column temperature maintained at 25°C; and mobile phase consisting of acetonitrile-0.1% formic acid solution (14:86). The flow rate was standardized to 1.0 ml/minute. Results: A good linear relationship between sample content and peak area was observed within the range of 0.051 μg to 0.816 μg for maohui isoflavone glycoside, with a relative standard deviation (RSD) of repeatability reaching 1.47%. The average recovery rate was found to be 98.21%, with an RSD of 2.31%. Conclusion: This method demonstrates excellent stability, high accuracy, precision, and reproducibility, making it suitable for quality control of Qianliekang tablets.

Differential expression of steviol glycoside pathway genes in NaCl-treated stevia genotypes with varied SG contents

The rebaudioside-A/stevioside (R/S) ratio influences the breeding and commercial values of stevia genotypes. Three stevia genotypes, “High Sugar,” “Levan,” and “ShouA3-2,” with respectively high, medium, and low steviol glycoside (SG) contents were investigated to answer the following questions: how do SG contents change when NaCl induces gene expression? Is SG-content positively correlated with NaCl tolerance? Does the genotype, with a high R/S ratio, exhibit higher expression of SG genes; compared to the genotype, with a low R/S ratio? Growth parameters, through our results, were decreased in “High Sugar” and “ShouA3-2” relative to “Levan” who showed better performance under the severe 200 mM NaCl treatment. Extendedly, “High Sugar” decreased the expression of SG-genes (cpps, ks, kh, and ugt74) under the low 50 NaCl treatments, while the “ShouA3-2” has upregulated all the genes (except ks) under the moderate (100 mM) NaCl treatments. Overall, the antioxidant sod1 gene was upregulated, similarly, the “Levan” has upregulated the cpps, while differentially expressed ks and kh across the NaCl treatments. In conclusion, high R/S ratio does not necessarily mean enhancement in responses to abiotic stresses in stevia. The R/S ratio in stevia does not solely rely on the expression of SG-pathway genes thus; other ancestral genetic elements may independently regulate them. Under salinity, the rooting characteristics improved when R/S ratio was low, while when moderate the shooting characteristics were superior. We recommend breeding for moderate R/S ratios to assure probable resilience to challenging climates (such as salinity) and potent higher agronomic traits.

Development and Validation of an Analytical Procedure for Determining Convallatoxin in Medicinal Products Containing Cardiac Glycosides of Lily of the Valley

INTRODUCTION. The safe use of lily-of-the-valley medicinal products requires adequately controlling the content of cardiac glycosides. The State Pharmacopoeia of the Russian Federation stipulates that the content of cardiac glycosides in lily-of-the-valley medicinal products should be quantified using bioassays and spectrophotometry. However, the determination of cardiac glycosides needs more accurate and selective physicochemical methods, such as high-performance liquid chromatography (HPLC).AIM. This study aimed to develop and validate an HPLC analytical procedure for the quantitative determination of cardiac glycosides (convallatoxin) in lily-of-the-valley herbal medicinal products.MATERIALS AND METHODS. The study examined the Lily-of-the-Valley Tincture, Zelenin Drops, Valocormid, Carniland®, and Lily-of-the-Valley Extract Reference Standard samples. The content of cardiac glycosides was determined by comparison with a reference standard for convallatoxin by HPLC and spectrophotometry. The samples were prepared as outlined in Monograph 3.4.0003.18 Lily-of-the-Valley Herb Tincture of the State Pharmacopoeia of the Russian Federation. Mixed cardiac glycosides were separated on a Luna 5 µm C18(2) column by gradient elution with 0.1% orthophosphoric acid in water and acetonitrile. The analysis was performed using an autoinjector with sample cooling to 5 °C.RESULTS. The developed analytical procedure met the acceptance criteria for specificity, intermediate precision, linearity (correlation coefficient of 0.99985), and repeatability (relative standard deviation of convallatoxin measurements of 1.61%). The analytical procedure is suitable for the quantitative determination of convallatoxin in lily-of-the-valley herbal medicinal products because it produces reliable and repeatable results.CONCLUSIONS. The authors developed a highly sensitive and selective HPLC analytical procedure for the quantitative determination of convallatoxin in lily-of-the-valley herbal medicinal products. The content of convallatoxin ranged from 0.012 to 0.018 mg/mL in the liquid active substance Lily-of-the-Valley Tincture, from 0.004 to 0.013 mg/mL in the medicinal product Zelenin Drops, and from 0.005 to 0.007 mg/mL in the medicinal products Carniland® and Valocormid. For the Lily-of-the-Valley Extract Reference Standard, the content of convallatoxin amounted to 0.029 mg/mL.

매실 추숙에 따른 매실 및 매실청의 시안배당체 함량 변화

This study investigated the yellowing phenomenon of maesil (Prunus mume), changes in organic acid (OA), and cyanogenic glycoside (CN-Glc) contents during post-harvest ripening, and the potential use of ripened maesil as raw material for CN-Glc-reduced maesil chungs. Ripening conditions were as follows: 5℃ for Ripening I, 20–22℃ with 50–60% RH for Ripening II, 20–22℃ with 50–60% RH after ultrasonic washing of maesil for Ripening II-US, and 35℃ and 80–90% RH for Ripening III. Yellowing did not occur in maesil under Ripening I even after 7 days, but was observed after 7 days of Ripening II and Ripening II-US, and after 3 days under Ripening III. The OA content slightly decreased under all ripening conditions, while CN-Glc content significantly decreased, with ripening under all ripening conditions, with Ripening II and Ripening II-US being the most effective at reducing CN-Glc levels. In maesil chungs prepared from ripened maesil CN-Glc content was significantly lower than that of those made with untreated maesil. These results demonstrate that ripening under the conditions tested in this study significantly reduces CN-Glc content in maesil with minimal reduction in OA content, enabling the preparation of CN-Glc-reduced processed maesil products.

The Cost of Self-Defense: Browsing Effects in the Rare Plant Species Salix arizonica.

Coevolution between plants and their animal predators has led to diverse defensive adaptations. Multiple theories of defense propose that there are resource allocation costs associated with producing chemical defenses. One leading hypothesis, optimal defense theory (ODT), suggests that natural selection will result in the allocation of resources to defenses that optimize the cost-to-benefit ratio between defense and other functional processes. The population decline of the rare subalpine wetland species, Arizona willow (Salix arizonica), has been attributed to various biotic and abiotic factors, with browsing from wild and domestic ungulates as a significant concern for at least three decades. In a field experiment using natural populations, we compare the relationship between phytochemical defense and height in Arizona willows with and without long-term protection from browsing via browse exclosures. Consistent with the predictions of ODT, individuals with physical protection from ungulate browsing for multiple years had significantly lower phenolic glycoside (PG) concentrations and increased plant height compared to unprotected individuals. A similar pattern was found across all individuals, whereby total PG concentration and height were negatively correlated. In a short-term experiment in natural populations, changes in levels of defense were not observed when plants received protection for only one growing season. The contrasting pattern of defense plasticity in response to long-term versus short-term physical protection suggests a differential plastic response in this long-lived species. Delayed reduction in PG concentration may serve as a benefit to avoid mismatches between environmental cues and responses. Our research sheds light on the intricate dynamics between plant-defense strategies, environmental pressures, and evolutionary adaptations in shaping plant-browser interactions.

THE EFFECT OF DİFFERENT PROCESSİNG METHODS ON AMYGDALİN LEVELS AND SOME PHYSİCOCHEMİCAL PROPERTİES OF APRİCOT KERNELS

Apricot seeds, particularly bitter seeds, pose health risks due to their cyanogenic glycosides content. Therefore, determining the amount of amygdalin in seeds is important for the food industry. In this study, the amygdalin content of sweet apricot varieties Hacıhaliloğlu and Kabaaşı, as well as bitter apricot (zerdali), was determined using LS-MS/MS devices. Methods to reduce the amygdalin levels in raw apricot seeds to safe consumption limits were established. The treatments to remove bitterness included sodium bicarbonate alkalinization (4-10% NaHCO3 for 7-15 min), ultrasonic waves (30-50°C for 30-60 min), microwave (240W-560W for 2-5 min), and roasting (120-160°C for 10-20 min). After all treatments, samples were analyzed for fat content, protein, amygdalin content via HCN, antioxidant activity, phenolic compounds, and color values (L, a*, b*, Chroma, Hue) using Soxhlet extraction. The fat content (42.99, 44.35, 40.75 ), protein content (34.14, 30.36, 29.27), and hydrocyanic acid content (mg/kg) (24.56, 30.31, 1630.66) of Hacıhaliloğlu, Kabaaşı, and zerdali varieties were found, respectively. Among the methods used to reduce or eliminate the amygdalin content of raw apricot seeds, roasting emerged as the most effective. For raw zerdali seeds, the amygdalin content was 27.64 mg/g, which decreased to 9.77 after 10 min of roasting at 160°C. In terms of total phenolic content, sweet and bitter seeds had similar values. The antioxidant activity (mg TE/100g) was 82.59 for raw zerdali seeds, with the lowest being for sodium bicarbonate (81.72), ultrasonic (57.5), microwave (52.65), and roasting (97.04) treatments.

Geographical distribution of caudatoside and ptaquiloside in bracken ferns in Northern Europe

Bracken ferns (genus Pteridium) are among the most prevalent plants worldwide, with their distribution expanding due to their invasive nature. The environmental implications of their proliferation in areas affected by human activity, natural disasters, or land-use changes are concerning, primarily because of the carcinogenic illudane glycosides they produce. These compounds cause domestic and wildlife animal poisoning, as well as contamination of dairy products and drinking water. Several illudane glycosides are known, but usually only ptaquiloside (PTA) is monitored. This study investigates the spatial and temporal variations in illudane glycosides PTA, caudatoside (CAU) and ptesculentoside (PTE) across two phenotypes of Pteridium aquilinum (vars. aquilinum and latiusculum) over a broad geographic range spanning Denmark, Sweden, and Finland, encompassing 66 locations. We analysed different parts of the fern fronds (the tips and the lowest pinnae) using LC–MS and statistically explored the influence of phenotype, frond part, geographic location, sunlight exposure, and the surrounding ecosystem on glycoside content. Our findings reveal that PTA accounts for approximately two-thirds of the total illudane glycoside content, followed by CAU at nearly one-third, and a minor contribution from PTE. Glycoside levels were not influenced by phenotypic varieties or the studied environmental factors, but were significantly affected by geographic location. Specifically, CAU levels increased progressively towards the northeast, while PTA concentrations were highest in Denmark and markedly decreased in northeastern countries by over threefold, presumably due to climatic gradient. It has been further supported by temporal analysis in selected PTA-dominant regions indicating a reduction in PTA towards the end of the growing season, aligning its levels with those of CAU. Our study highlights that CAU concentrations in bracken ferns may equal or surpass PTA, contesting the prevailing view that PTA is the only notable illudane glycoside in Bracken. To provide unbiased assessment of the potential risks posed by P. aquilinum in the region, environmental and toxicological research should include measurements of not only PTA, but also CAU and, if possible, PTE.

Methyl jasmonate mitigates biochemical and phytochemical changes in salt stressed Stevia rebaudiana plants

This study explored the effects of salt stress on growth, oxidative stress, and steviol glycoside content in Stevia rebaudiana Bertoni plants cultivated in soil supplemented with methyl jasmonate (MeJA). Stevia plants were cultivated under normal and salt stress conditions, with and without MeJA supplements of 30 ?M, 60 ?M, and 120 ?M. Samples were harvested after the 1st, 3rd, 5th, 10th, and 15th day of treatment. The levels of chlorophyll (p<0.0001), carotenoids (p<0.0001), and antioxidant enzymes such as catalase (p<0.0001), superoxide dismutase (p<0.0001), APX (p<0.0001), and glutathione reductase (p<0.0001) were observed. The quantification of steviol glycosides, including stevioside (p<0.0001) and rebaudioside-A (p<0.0001), was studied by the most advanced hyphenated technique, LC-MS/MS. The study revealed that the oxidative stress responses were significantly improved in MeJA-treated plants compared to salt-stress control plants. The level of production of phenols (p<0.0001), flavonoids, total sugar, reducing sugar, and steviol glucosides was significantly altered in salt-stress plants. MeJA showed a dose- and time-dependent significant effect on the improvement of these factors over salt stress. In conclusion, MeJA not only improves the growth of plants but also reduces oxidative stress and enhances the level of phytochemicals under saline stress.

Identification of bHLH transcription factors and screening of anthocyanin-related genes in Lagerstroemia indica.

The basic helix-loop-helix (bHLH) family is one of the three major transcription factor families that play important transcriptional regulatory roles in plant growth and development. One of the most crucial elements in defining Lagerstroemia indica's decorative qualities is flower color. However, the function of the bHLH transcription factor family in L. indica anthocyanin glycoside synthesis has not been clarified. Using the transcriptome data of flower color, 79 LibHLH genes were found in this study. Phylogenetic analysis showed that the LibHLH genes can be divided into 16 subfamilies, and most of the genes in the same subfamily have similar conserved motifs. The total anthocyanin glycoside content of L. indica 'Zihua Guifei' petals was determined during three developmental stages of the petals' growth. The results showed that the total anthocyanin glycoside content grew gradually with growth and development, and that it accumulated most during the full bloom stage. By using gene expression analysis, protein interaction network analysis, and bioinformatics, it was possible to determine which member of the III f family, LibHLH29, is important for the synthesis of anthocyanin glycosides in L. indica. Its expression was confirmed by qRT-PCR, and the results were essentially compatible with the transcriptome data. It was more prominent in the light-colored bloom stage the color-transition stage of L. indica 'Zihua Guifei'. It can be further investigated as a major candidate gene for regulating anthocyanin glycoside synthesis in L. indica, thus laying the foundation for an in-depth study of the interactions among transcription factors.

Comparison in Bioactive Compounds and Antioxidant Activity of Cheonggukjang Containing Mountain-Cultivated Ginseng Using Two Bacillus Genus.

In this study, the nutrients, phytochemicals (including isoflavone and ginsenoside derivatives), and antioxidant activities of cheonggukjang with different ratios (0%, 2.5%, 5%, and 10%) of mountain-cultivated ginseng (MCG) were compared and analyzed using microorganisms isolated from traditional cheonggukjang. The IDCK 30 and IDCK 40 strains were confirmed as Bacillus licheniformis and Bacillus subtilis, respectively, based on morphological, biological, biochemical, and molecular genetic identification, as well as cell wall fatty acid composition. The contents of amino acids and fatty acids showed no significant difference in relation to the ratio of MCG. After fermentation, isoflavone glycoside (such as daidzin, glycitin, and genistin) contents decreased, while aglycone (daidzein, glycitein, and genistein) contents increased. However, total ginsenoside contents were higher according to the ratio of MCG. After fermentation, ginsenoside Rg2, F2, and protopanaxadiol contents of cheonggukjang decreased. Conversely, ginsenoside Rg3 (2.5%: 56.51 → 89.43 μg/g, 5.0%: 65.56 → 94.71 μg/g, and 10%: 96.05 → 166.90 μg/g) and compound K (2.5%: 28.54 → 69.43 μg/g, 5.0%: 41.63 → 150.72 μg/g, and 10%: 96.23 → 231.33 μg/g) increased. The total phenolic and total flavonoid contents were higher with increasing ratios of MCG and fermentation (fermented cheonggukjang with 10% MCG: 13.60 GAE and 1.87 RE mg/g). Additionally, radical scavenging activities and ferric reducing/antioxidant power were significantly increased in fermented cheonggukjang. This study demonstrates that the quality of cheonggukjang improved, and cheonggukjang with MCG as natural antioxidants may be useful in food and pharmaceutical applications.

Bioefficacy of Methanolic Leaf Extracts from Coleus amboinicus and Mentha spicata against Aedes aegypti Mosquitoes

Mosquito-borne diseases (MBDs) pose significant public health challenges globally, with India and Sub-Saharan Africa accounting for the majority of cases. Aedes aegypti, a primary vector of dengue fever, thrives in an environment with inadequate water supply and poor waste management. The increasing resistance of mosquito population to chemical insecticides necessitates the exploration of alternative control strategies, such as botanical extracts. This study evaluates the adulticidal efficacy of methanolic leaf extracts of Coleus amboinicus and Mentha spicata against the adults of Ae. aegypti. Fresh leaves of both plants were collected, dried, and extracted with methanol. Phytochemical screening revealed a moderate presence of alkaloids, flavonoids, saponins, terpenoids, and glycosides in C. amboinicus, while phenols are highly prevalent, indicating significant biological activity. In contrast, M. spicata displayed a high concentration of alkaloids, flavonoids, and terpenoids, though saponins, phenols, and glycosides were less abundant. Adulticidal bioassays demonstrated that C. amboinicus achieved higher mortality rates across all concentrations compared to M. spicata. The LC50 value for C. amboinicus was 202.00 ppm, while M. spicata exhibited an LC50 of 230.00 ppm. Similarly, the LC90 values were 428.51 ppm and 457.40 ppm for C. amboinicus and M. spicata, respectively. These findings suggest that C. amboinicus has a more balanced and diverse phytochemical profile, which likely contributes to its superior adulticidal activity against Ae. aegypti. This study highlights the potential of C. amboinicus as a natural alternative for mosquito control, warranting further exploration and development for effective vector management.

Improving organoleptic and antioxidant properties by inhibition of novel miRstv_7 to target key genes of steviol glycosides biosynthetic pathway in Stevia rebaudiana Bertoni.

Stevioside (5-10%) and rebaudioside-A (2-4%) are well-characterized diterpene glycosides found in leaves of Stevia rebaudiana known to have natural sweetening properties with zero glycaemic index. Stevioside has after-taste bitterness, whereas rebaudioside-A is sweet in taste. The ratio of rebaudioside-A to stevioside needs to be changed in order to increase the effectiveness and palatability of this natural sweetener. Plant-specific miRNAs play a significant role in the regulation of metabolic pathways for the biosynthesis of economically important secondary metabolites. In this study inhibition of miRNA through antisense technology was employed to antagonize the repressive action of miRstv_7 on its target mRNAs involved in the steviol glycosides (SGs) biosynthesis pathway. In transgenic plants expressing anti-miRstv_7, reduced expression level of endogenous miRstv_7 was observed than the non-transformed plants. As a result, enhanced expression of target genes, viz. KO (Kaurene oxidase), KAH (Kaurenoic acid-13-hydroxylase), and UGT76G1 (UDP-glycosyltransferase 76G1) led to a significant increase in the rebaudioside-A to stevioside ratio. Furthermore, metabolome analysis revealed a significant increase in total steviol glycosides content as well as total flavonoids content. Thus, our study can be utilized to generate more palatable varieties of Stevia with improved nutraceutical values including better organoleptic and antioxidant properties.

Assesment of quality of Ginkgo biloba extract and dietary supplements in Vietnam market based on flavonol glycoside content and flavonoid ratio

Ginkgo biloba is one of the oldest medicinal herbs in the world. It is commonly used as a dietary supplement to protect against blood circulation disorders, improve memory, and prevent cognitive decline. Currently, Vietnam and other countries have regulations in place to ensure the quality of Ginkgo biloba extract in their pharmacopoeia. In this study, the quality of 11 raw materials and 120 dietary supplement products containing ginkgo extract was evaluated based on flavonol glycoside content and the ratio of component flavonoids. The results revealed a significant number of unsatisfactory samples, highlighting the need for closer monitoring of quality products to protect consumer rights.

Push-Pull Intercropping Increases the Antiherbivore Benzoxazinoid Glycoside Content in Maize Leaf Tissue.

Push-pull technology refers to a promising mixed cropping practice for sustainable agricultural intensification, which uses properties of intercrop and border crop species to defend a focal crop against pests. Currently, the most widely practiced system uses Desmodium spp. as intercrop and Brachiaria or Napier grass as border crops to protect maize (Zea mays) against both insect pests and parasitic weeds. Several previous studies have demonstrated the efficacy of the push-pull system, but research on the underlying chemical mechanisms has mostly been limited to laboratory and glasshouse experiments that may not fully reproduce the complexity of the system under natural conditions. To address this limitation, we performed a large-scale study in farmer-operated push-pull maize fields in three east African countries. We compared maize leaf extracts from plants grown on push-pull fields with maize from fields employing conventional agricultural practices to assess the influence of push-pull cultivation on the maize metabolome. We identified two benzoxazinoid glycosides, which are known to have antiherbivore properties and were present in greater relative abundance in push-pull-cultivated maize leaves across three countries. Our data thus suggest that maize cultivated under push-pull has an increased resistance to herbivore attack compared to maize grown under conventional local agricultural practices.