Total Proanthocyanidin Contents Research Articles

Evaluation of the Secondary Metabolites and Bioactivity of South African Bulbine Natalensis Under Simultaneous Elevated Carbon Dioxide and Temperatures

The secondary metabolism in medicinal plants are responsible for their protection against environmental factors and the health-promoting benefits they provide to users. The purpose of this study was to assess the responses of the secondary metabolic system of B. natalensis and its influence on the antioxidant and antibacterial activities. The phytochemical analyses, antioxidant and antibacterial assays were conducted from using harvested leaves, underground stems and roots from whole plants exposed to simultaneous elevated CO2 and temperatures over eight days in a heatwave simulation. Most of the phytochemical groups were present in the leaves, however majority of the tested compounds had consistent presence throughout the plants in all treatments. The underground stems possessed a greater total phenolic, tannin and proanthocyanidin contents than the leaves and roots under elevated CO2 and temperatures. The leaves had a comparatively better antioxidant activity from the treatment than control. Overall, there was consistency in the antibacterial activity in both control and experimental conditions. The tannins and phenolics had greater concentrations throughout the plants under elevated conditions overall, which could indicate their leading role in plant defence and the improvement and maintenance of the medicinal activity of B. natalensis. The responses of the plant parts of B. natalensis under elevated CO2 and temperatures provides newfound insights on the physiological roles plant organs play on the overall productivity and medicinal activity of the species.

Effect of low molecular weight phenols on the in-mouth sensory perception of high molecular weight phenols by analyzing reconstituted wines

This research aimed to assess the contribution of monomeric phenols to the perception of bitterness and astringency by means of wine reconstitution experiments. Six wines with distinct total polyphenol indexes were selected and fractioned by preparative liquid chromatography into two fractions. Thirty-one reconstituted wines were prepared by combining distinct low molecular weight fractions (L) with different high molecular weight fractions (H). In-mouth attributes of reconstituted and reference wines were described by a trained sensory panel. Fractions were chemically characterized by UPLC-MS. No significant differences among sensory results were found between reference and reconstituted wines. Bitterness and astringency perception were strongly influenced by total proanthocyanidins content. Flavan-3-ol monomers and dimers were only responsible for astringency in wines with a low content of proanthocyanidins, as was the case in rosé wine. Quercetin-3-O-glucuronide and several anthocyanins presented correlations with bitterness in the reconstituted wines; notwithstanding, several interactions with this attribute were observed.

Antioxidant and Antibacterial Activities of Selected Medicinal Plants from Addis Ababa against MDR-Uropathogenic Bacteria.

This study determined the antioxidant and antibacterial activities of Thymus schimperi (Ts), Rhamnus prinoides (Rp), and Justicia schimperiana (Js) from Addis Ababa against MDR-Uropathogenic bacteria. Accordingly, Thymus schimperi had the highest total phenolic (TPC), flavonoid (TFC) and proanthocyanidin content. In Ts, the GC-MS analyses predicted 14 bioactive compounds. And among these, hexanedioic acid, bis(2-ethylhexyl) ester, thymol, and o-cymen-5-ol were the most predominant compounds, respectively. Six compounds were also predicted in Rp, where hexanedioic acid, bis(2-ethylhexyl) ester, β-D-glucopyranoside, methyl, and desulphosinigrin were the predominant, respectively. Whereas in the Js extract, five bioactive compounds were predicted, with hexanedioic acid, mono (2-ethylhexyl) ester, debrisoquine, and 8,11,14-heptadecatrienoate, methyl ester being predominant compounds, respectively. The extracts' TPC showed a strong negative correlation with the DPPH (2,2-diphenyl-1-picrylhydrazyl) assay (r = -0.999; p = 0.023). In addition, the TFC correlated significantly with the ABTS (2,2'-azino-di-(3-ethylbenzthiazoline sulfonic acid)) assay (r = 0.999; p = 0.032). Thymus schimperi showed the highest antibacterial activity against clinical isolates of Escherichia coli and Klebsiella pneumoniae ESBL at 1000 mg/mL, and Ts had the lowest MIC (4 mg/mL) among evaluated extracts against E. coli (ATCC25922). In conclusion, Ts and Rp possess higher predicted bioactive molecules, including antioxidant and antibacterial activities, which are potentially useful in treating urinary tract infections.

Antioxidant potentials of Acanthus ilicifolius leaves from Southwest Coastal Region of Bangladesh

This research delves into the antioxidant potential of Acanthus ilicifolius leaves harvested from the southwestern coastal region of Bangladesh. Four distinct solvents—methanol, ethanol, acetone, and ethyl acetate—were utilized to determine antioxidant activities. Initial phytochemical screening unveiled the existence of many secondary metabolites, including as flavonoids, phenols, alkaloids, and others. Total phenolic content, total flavonoid content, and total proanthocyanidin content were determined using quantitative analysis. The assessment of antioxidant activity was conducted using the 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2-Azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) scavenging assays. Notably, the acetone extract of Acanthus ilicifolius exhibited the highest total phenolic content (24.75 mg of GA/g), total flavonoid content (12.9 mg of catechin/g), and total proanthocyanidins content (11.47 mg of catechin/g). The ethanol extract displayed the most robust antioxidant activity in both DPPH (91.41 %) and ABTS (66.78 %) scavenging assays among the crude extracts, underscoring its potential as a valuable source of antioxidants. The results emphasise the crucial importance of choosing the appropriate solvent in the extraction procedure and suggest that Acanthus ilicifolius leaves, particularly when extracted with ethanol, acetone, or methanol, hold promise as a natural source of antioxidants. This study offers valuable insights into the bioactive potential of Acanthus ilicifolius leaves.

WITHDRAWN: Optimization of conventional extraction of phenolic compounds and antioxidant activity from myrtle (Myrtus communis L.) fruit

This study aimed to extract phenolic compounds from myrtle (Myrtus communis L.) fruits. The extraction of polyphenols from myrtle berries using a conventional solid-liquid extraction was optimized using single factor experiments. The influence of several parameters such as the type of solvent (50% acetone, 50% methanol, 50% ethanol and water), solvent concentration (30-100%; v/v), solvent acidity (0-0.1N), temperature (20-40°C), and time (30-360min) on the yield extraction of total phenolic content (TPC), total flavonoid content (TFC), total proanthocyanidin content (TPAC), and on the antioxidant activity including DPPH-radical scavenging activity (DPPH-RSA), ABTS-radical scavenging activity (ABTS-RSA) and ferric reducing power (FRP) were studied. The results showed that 50% acetone without acidification, 40°C and 180min are the best conditions for extracting TPC (87mg GAE/g DW), TFC (12mg QE/g DW), and TPAC (76mg CE/g DW). Myrtle berries extracted under these conditions also exhibited the strongest antioxidant activity: DPPH-RSA (7166mg TE/g DW), ABTS-RSA (164mg TE/g DW), and FRP (69mg AAE/g DW). Pearson correlation coefficients showed a good positive correlation between TPC, TFC and TPAC and antioxidant activities (DPPH-RSA, ABTS-RSA and FRP), mainly under the effect of solvent type (0.93 < r < 0.99) and solvent concentration (0.91 < r < 0.99). These results suggested that myrtle berries may serve as a good source of natural antioxidants with high antioxidant potential. Therefore, it could be useful in developing functional foods and nutraceuticals.

Foliar application of sodium selenite affects the growth, antioxidant system, and fruit quality of strawberry.

Selenium (Se) plays a vital role in various physiological processes in plants and is regarded as an essential micronutrient for human health as well. In this study, sodium selenite solution at 10, 40, 70, and 100 mg·L-1 concentrations was foliar sprayed, and the strawberry plant growth, antioxidant system, and fruit quality with an emphasis on sugar and acid content were assessed. The results showed that 10 mg·L-1 of sodium selenite treatment promoted plant growth, while all the treated concentrations could enhance photosynthesis, the antioxidant system in leaves, the content of Se, and ascorbic acid in fruits. More importantly, 40 mg·L-1 sodium selenite treatment significantly increased fruit weight, total soluble solid, total phenolic content, and anthocyanins, as well as improved the shape index. Furthermore, it decreased the total flavonoid and proanthocyanidin content. Particularly, sodium selenite treatment at 40 and 70 mg·L-1 largely increased the ratio of soluble sugars to titratable acid. The changes of predominant sugars and organic acids during fruit development were further investigated. The sucrose, fructose, and glucose content was upregulated by sodium selenite treatment through upregulating the activities of sucrose phosphate synthase (SPS) and acid invertase, as well as the FaSPS expression. In addition, sodium selenite treatment inhibited the activity of citrate synthase and phosphoenolpyruvate carboxylase, rather than modulating their transcript levels to reduce the citric acid content. This work presented a potentially efficient approach to enhance plant growth and fruit quality and supplement Se in strawberry, providing insights into the mechanism of regulating sugar and acid metabolism by Se.

Antioxidant Effects and Fatty Acid Analysis of Leucojum aestivum Seed Coat Extracts

The aim of this study is to analyze the biochemical composition and antioxidant activity of Leucojum aestivum seed coats. In the crude extract the total phenolic content was determined to be 129.55 ± 1.94 mg gallic acid equivalent (GAE)/g, while the total flavonoid content was found to be 210.21 ± 7.91 mg quercetin equivalent (QE)/g. Additionally, the total flavonol, tannin, and proanthocyanidin contents were determined to be 9.63 ± 5.16 mg QE/g, 3.32 ± 0.14 mg GAE/g, and 129.89 ± 6.10 mg catechin equivalent (CAE)/g, respectively. Furthermore, the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity showed a significant antioxidant potential with a concentration that results in 50% decrease in the initial DPPH concentration IC50 value of 214.97 ± 50.44 mg QE/g in the crude extract. GC/MS analysis revealed the presence of various biologically active compounds, including hexadecanoic acid, oleic acid, and stigmasterol. Moreover, galantamine and galathan were identified in the seed coat extracts. Fatty acid analysis indicated the presence of compounds such as linoleic acid, oleic acid, and palmitic acid. This comprehensive study provides a detailed examination of seed coats and highlights the presence of biologically active compounds such as galantamine. This finding represents a study conducted for the first time in the literature, as no similar research focusing on L. aestivum seed coats has been conducted previously. Therefore, the results of the study provide new insights into the potential biological and pharmacological effects of seed coats and offer significant findings that could serve as a basis for future research.

Chemical Characterization and Biological Activities Evaluation of Myrtus communis L. Essential Oil Extraction By-Product towards Circular Economy and Sustainability.

Essential oil (EO) extraction is a widespread practice generating huge amounts of solid plant by-products a potential source of bioactive compounds, on the one hand, and a detrimental risk for the environment that needs to be carefully considered on the other hand. The present study aims to valorize Myrtus communis L. leaf by-products obtained following EO extraction using a steam distillation unit through the recovery of phenolic compounds and the evaluation of their biological activities. The total phenols, flavonoids, and proanthocyanidins contents of the ethanolic extract by-product were higher than the control (leaves without extraction of EO). Their amounts increased from 69.30 to 88.06 mg GAE/g for total phenols, from 36.31 to 70.97 mg QE for flavonoids and from 19.74 to 21.49 mg CE/g of extract for proanthocyanidins. The identification of phenolic compounds by high-performance liquid-chromatography equipped with a reversed-phase (RP-HPLC) system revealed that the by-product sample includes more gallic acid, catechin, syringic acid and luteolin 7-O-glucoside but less p-coumaric acid and kaempferol than the control. Moreover, the mid-infrared spectroscopy (MIR) showed the presence of benzene ring characteristic of phenolic compounds at 756 cm-1, esters of aromatic acids and stretching vibrations of polyphenols at 1141-1234 cm-1, C=C stretching present in phenolic acids such as coumaric acid and catechin at 1604 cm-1. The assessment of antioxidant activity revealed that the ABTS+• radical scavenging activity was significantly increased, whereas the DPPH• radical inhibition activity and the ferric reduction antioxidant power were significantly decreased. The results indicated, as well, that Myrtus communis L. leaf by-products maintained a considerable antibacterial activity depending on the tested bacterial strain. Additionally, the anti-α-amylase activity was higher for the Myrtus communis L. leaf by-product extract. Therefore, Myrtus communis L. leaf by-products of EO extraction offer phenolic compounds with significant biological activities, contributing to the sustainable development and the promotion of circular economy by the recovery of valuable inputs from plant by-products.

PHENOLIC AND ANTIOXIDANT PROFILE: FTIR AND LC-MS ANALYSES OF SERAPIAS ORIENTALIS

Objective: The objective of this study is to characterize the aerial parts of S. orientalis using Fourier Transform Infrared (FTIR) spectroscopy, evaluate the phenolic content and antioxidant activity of seeds, stems, and flowers, and conduct quantitative analysis of phenolic compounds using LC-MS/MS. Material and Method: Fourier Transform Infrared (FTIR) spectroscopy was employed to characterize the aerial parts of S. orientalis. The analysis focused on identifying various functional groups such as -OH vibrations associated with polysaccharides, C-H vibrations from lipids and lignin compounds, and C=O vibrations related to cellulose derivatives. The total phenolic, flavonoid, flavanol, tannin, and proanthocyanidin contents of S. orientalis seeds, stems, and flowers were evaluated using standard analytical methods. DPPH radical scavenging activity was determined to assess antioxidant potential, with IC50 values calculated for each plant part. Quantitative analysis of phenolic compounds in the plant extract was conducted using LC-MS/MS. The abundance of various phenolic acids including P-coumaric acid, trans-ferulic acid, caffeic acid, and vanillic acid was determined. Additionally, other phenolic compounds such as gallic acid, chlorogenic acid, salicylic acid, (+) taxifolin, rutin hydrate, ellagic acid, quercetin dihydrate, and apigenin were also detected and quantified. Result and Discussion: The evaluation of phenolic content showed differences among different plant parts, with flowers exhibiting the highest total phenolic and proanthocyanidin content. Seeds demonstrated superior DPPH radical scavenging activity. Quantitative analysis of phenolic compounds using LC-MS/MS highlighted the abundance of various phenolic acids and other phenolic compounds in S. orientalis. These findings underscore the potential of S. orientalis as a valuable source of natural antioxidants. Overall, the results suggest that S. orientalis possesses significant phenolic diversity and antioxidant activity, which could contribute to its potential applications in various industries, including pharmaceuticals and nutraceuticals.

Seasonal Variation and Mean Degree of Polymerization of Proanthocyanidin in Leaves and Branches of Rabbiteye Blueberry (Vaccinium virgatum Aiton).

The leaves and branches of rabbiteye blueberry are rich in proanthocyanidins, which are thought to have different physiological activities depending on their structure and degree of polymerization. In this study, we analyzed the constituents of the leaves and branches of rabbiteye blueberry to determine the seasonal variations in polyphenol and proanthocyanidin (PAC) contents as well as their mean degrees of polymerization (mDP). Total PAC content was determined using two methods: The p-dimethylaminocinnamaldehyde (DMACA) method, which measures monomeric PAC, showed an increase from spring to summer in both leaves and branches. On the other hand, using the butanol/HCl method, which measures only polymerized PAC, the PAC content of leaves increased from spring to summer but those of branches remained low throughout the year, showing no significant increase or decrease. Furthermore, analysis of the mDP of PAC showed increases from spring to summer in the leaves of 'Kunisato 35 gou'. Although the highest value (8.0) was observed in October, values around 4 remained throughout the year in the branches. Since differences in polymerization degree affect absorption in the body and physiological properties such as antioxidant capacity, selecting the appropriate harvest time and plant organs for each purpose is expected to ensure the quality of processed blueberry foods.

Variation in leaf morphology and architecture, phytochemical content, and antioxidant capacity among 36 Camellia sinensis clones of the Indian sub-Himalayan region

Camellia sinensis, renowned as the second most widely consumed nonalcoholic beverage worldwide, bears substantial economic importance, prompting cultivators to breed various clones for enhanced flavor and quality. This study analyzed the variation in leaf phenotype, phytochemicals (total tannins and proanthocyanidins content) and antioxidant potential of 36 widely cultivated tea clones from India’s sub-Himalayan region using multivariate analysis. Results indicated that TV23 had the largest leaf and SS27 and RR had the smallest. TS520 was the richest in tannin, proanthocyanidins, and antioxidants, while S3A1 and Heeleakah were the least. Principal components analysis (PCA) and cluster analysis unveiled four morphological clusters (representative clones - TV1, TV23, TV30, 124.48.8) and four phytochemical clusters (representative clones - TS520, TV9, TV27, P126). GC-MS analysis revealed that TV1 and TV30 had high caffeine content (82.0%), while TS520 exhibited abundant antioxidant compounds, including sycllo-inositol (23.84%) and epigallocatechin (4.23%). TS520’s exceptional antioxidant properties, confirmed by DPPH, ABTS, and total antioxidant capacity assays, may result from its cultivation through seed propagation. Correlation analysis showed antioxidant potential had moderate negative associations with leaf size, strong negative with inter-secondary vein number, and positive with petiole length. This study is pivotal for assessing tea clone diversity, with broader applications in tea improvement and breeding programs.

Solvent Effects on the Phenolic Compounds and Antioxidant Activity Associated with Camellia polyodonta Flower Extracts.

Camellia polyodonta flowers contain limited information available regarding the composition of their bioactive compounds and activity. The objective of this study was to identify phenolic compounds and investigate the effect of different solvents (ethanol and methanol) on the phenolic content and antioxidant activity in C. polyodonta flowers. The analysis using UPLC-Q-TOF-MS/MS revealed the presence of 105 phytochemicals and the most common compounds were flavonols, procyanidins, and ellagitannins. Interestingly, flavonol triglycosides were identified for the first time in these flowers. The study demonstrated that the concentration of the solvent had a significant impact on the total phenolic compound (TPC), total flavonoid compound (TFC), and total proanthocyanidin content (TPAC). The TPC, TFC, and TPAC showed a remarkable increase with the increasing concentration of the solvent, reaching their maximum levels (138.23 mg GAE/g DW, 421.62 mg RE/g DW, 60.77 mg PB2E/g DW) at 70% ethanol. However, the total anthocyanin content reached its maximum at low concentrations (0.49 mg CGE/g DW). Similar trends were observed in the antioxidant activity, as measured by the DPPH· assay (DPPH radical scavenging activity), ABTS·+ assay (ABTS radical cation scavenging activity), and FRAP assay (Ferric reducing antioxidant power). The maximum antioxidant activity was observed at 100% solvents and 70% methanol. Among the 14 individual phenolic compounds, 70% methanol yielded the highest content for 8 (cyanidin-3-O-glucoside, procyanidin B2, procyanidin B4, epicatechin, rutin, kaempferol-3-O-rutinoside, astragaline and quercitrin) out of the 14 compounds. Additionally, it was found that epicatechin was the most abundant phenolic compound, accounting for approximately 20339.37 μg/g DW. Based on these findings, it can be concluded that 70% methanol is the most effective solvent for extracting polyphenols from C. polyodonta flowers. These results provided chemical information and potential antioxidant value for further research in C. polyodonta flowers.

Purification of Phenolic Compounds from Camellia polyodonta Flower: Composition Analysis, Antioxidant Property, and Hypolipidemic Activity In Vitro and In Vivo.

Camellia polyodonta flowers are rich sources of phenolics and less attention has been paid to their potential biological activity. This study aims to explore the crude extracts and resulting purified fractions (CPFP-I, II, III, and IV) through compositional analysis and antioxidant and hypolipidemic activities in vitro and in vivo. Among four fractions, CPFP-II contained the highest total phenolic content and flavonoid content, while CPFP-III exhibited the greatest total proanthocyanidin content. Among the 14 phenolic compounds, CPFP-II displayed the highest content of procyanidin B2, B4, and C1, whereas CPFP-III contained the highest amount of 1,2,3,6-tetragalloylglucose. The DPPH, ABTS, and FRAP assessments demonstrated a consistent trend: CPFP-II > CPFP-III > CPFP-I > CPFP-IV. In vivo experiments showed that that all four fractions significantly reduced lipid levels in hyperlipidemic C. elegans (p < 0.05), with CPFP-II exhibiting the most potent effect. Furthermore, CPFP-II effectively bound to bile acids and inhibited the enzymatic activity of pancreatic lipase in vitro. Consequently, CPFP-II should be prioritized as a promising fraction for further exploration and should provide substantial support for the feasibility of the C. polyodonta flower as a natural alternative.

Nutritional Traits, Pasting Properties and Antioxidant Profile of Selected Genotypes of Sorghum, Oat and Maize Eligible for Gluten-Free Products.

The technological and nutritional traits of food-grade sorghum hybrids, hulled/naked oat varieties and maize genotypes of different colors were studied for novel and healthier gluten-free foods. Oat genotypes showed the highest protein content, followed by maize and sorghum. The total starch and the total dietary fiber content were quite similar among the three species. Great variation was found in the amylose content, and the highest was in sorghum (27.12%), followed by oat 16.71% and maize 10.59%. Regarding the pasting profile, the rank of Peak Viscosity was sorghum (742.8 Brabender Unit, BU), followed by maize (729.3 BU) and oat (685.9 BU). Oat and sorghum genotypes had similar average breakdown (407.7 and 419.9 BU, respectively) and setback (690.7 and 682.1 BU, respectively), whereas maize showed lower values for both parameters (384.1 BU and 616.2 BU, respectively). The total antioxidant capacity, only in maize, significantly correlated with total flavonoid, phenolic and proanthocyanidin contents, indicating that all the measured compounds contributed to antioxidant capacity. The study indicated the importance of sounding out the nutritional and technological characteristics of gluten-free cereals in order to select suitable cultivars to be processed in different gluten-free foods with better and healthier quality.

Phenolic Compounds in Berries of Winter-Resistant Actinidia arguta Miq. and Actinidia kolomikta Maxim.: Evidence of Antioxidative Activity.

Variations between fruit cultivars can significantly impact their biochemical composition. The present research examined the variability in the qualitative and quantitative content of phenolic compounds in berry extracts of Actinidia kolomikta and Actinidia arguta cultivars. Additionally, antioxidant activities of berry extracts were evaluated. The total phenolic, flavonoid, proanthocyanidin contents and hydroxycinnamic acid derivatives were determined using the appropriate methodologies. The average amount of phenolic compounds in A. kolomikta berries (177.80 mg/g) was three times higher than that of A. arguta (54.45 mg/g). Our findings revealed that berries of A. kolomikta and A. arguta accumulated, on average, 1.58 RE/g DW (rutin equivalent/g dry weight) and 0.615 mg RE/g DW of total flavonoids, 1439.31 mg EE/g DW (epicatechin equivalent/g dry weight) and 439.97 mg EE/g DW of proanthocyanidins, and 23.51 mg CAE/g DW (chlorogenic acid equivalent/g dry weight) and 5.65 mg CAE/g DW of hydroxycinnamic acid derivatives, respectively. The cultivars of both species were characterized by higher antioxidant activity of total phenolic compounds determined using CUPRAC and FRAP methods compared to the ABTS•+ method. The variability in phenolic compounds' qualitative and quantitative content in tested berry extracts was evaluated by applying ultra-high performance liquid chromatography (UHPLC) coupled to mass spectrometry in tandem with electrospray ionization. Significant intraspecific differences in the amounts of total phenolic compounds, total flavonoid compounds, proanthocyanidins, and hydroxycinnamic acid derivatives were determined among cultivars. Four phenolic acids, eight flavonols, two flavones, and five flavon-3-ols were identified in the berry extracts.

Comparative Phytochemical Profiling and Biological Activities in the Flowers and Stalks of Tulbaghia violacea

Tulbaghia violacea is indigenous to Southern Africa and has been used extensively in traditional medicine in this region. Extensive research has been documented on the bioactive compounds found in the leaves and roots but not in the flowers and stalks. Thus, this study assessed the phytochemical profile and biological activities in the flowers and stalks of T. violacea. Methanolic and aqueous extracts of the air and freeze-dried T. violacea were screened for phytochemicals, and then antioxidant and antibacterial assays were performed. Phytochemicals such as phenols, tannins, flavonoids, coumarins, and terpenoids are present in either of the tested plant parts. The flowers contain most of the phytochemicals being tested and a higher total phenolic, tannin, and proanthocyanidin content than the stalks. The flowers exhibit the strongest scavenging activity against 2,2-diphenylpicryhydrazyl radicals and metal oxidants. The hydrogen peroxide scavenging activities show that the aqueous flower extracts have a higher radical scavenging activity than stalks. In contrast, the methanolic stalk extracts have a higher antioxidant activity than the flowers. Antibacterial activity is only exhibited in the flowers, showing resistant and intermediate inhibition zones of Escherichia coli and Staphylococcus aureus growth, respectively. This study validates the use of T. violacea in traditional medicine, and these results are significant for conserving the species as specific plant parts can be harvested to treat specific ailments. This study suggests the potential application of T. violacea, particularly the flowers and stalks, in the pharmaceutical and cosmetic sectors.

저온 저장 후지 사과의 과피와 과육 중 파이토케미컬 함량의 상관관계

This study determined the relationships between the total anthocyanin content in apple skin and the total polyphenols, flavonoids, proanthocyanidins, and soluble solids contents in the flesh of cold-stored Fuji apples. Total anthocyanin content in apple skin ranged from 0.130±0.005 mg CE/g fw to 0.262±0.028 mg CE/g fw, and the overall average was 0.200±0.008 mg CE/g fw. The total polyphenolic compounds in the flesh was ranged from a 4.283±0.141 mM GAE/g fw to 8.207±0.234 mM GAE/g fw, and the average content was 6.275±0.177 mM GAE/g fw. The total flavonoid content ranged from 4.510±0.080 mM QE/g fw to 2.467±0.458 mM QE/g fw, and the average total flavonoid content was about 3.586 mM QE/g fw. The total proanthocyanidin content was relatively high, ranging from 3.475±0.577 mM EE/g fw to 6.816±0.277 mM EE/g fw, and the soluble solid in the flesh was about 12 °Brix to 14 °Brix. The DPPH radical scavenging activity of extracts from apple flesh ranged from 66.36% to 94.99%, and the ascorbate equivalent concentration was 0.482 mM. The ABTS radical scavenging activity was 99.12% to 99.9%, indicating a higher inhibitory activity than the DPPH inhibitory activity, and the ascorbate equivalent concentration was 0.486 mM. The correlation between the total anthocyanin and total polyphenolic compounds was y = 15.192x + 3.2169 (R2=0.2748), but the concentration of total polyphenolic compounds increased when the total anthocyanin content was increased. The correlation equation of total anthocyanin with total flavonoids was y = 15.18x + 0.5555 (R2=0.6226), with total proanthocyanin was y = 14.918x + 2.3422 (R2=0.3372), and with soluble solid was y = 10.558x + 11.126 (R2=0.1925), indicating that the correlation of total anthocyanin with total flavonoid was higher than that with soluble solid.

Non-Mature miRNA-Encoded Micropeptide miPEP166c Stimulates Anthocyanin and Proanthocyanidin Synthesis in Grape Berry Cells.

The phenylpropanoid and flavonoid pathways exhibit intricate regulation, not only influenced by environmental factors and a complex network of transcription factors but also by post-transcriptional regulation, such as silencing by microRNAs and miRNA-encoded micropeptides (miPEPs). VviMYBC2-L1 serves as a transcriptional repressor for flavonoids, playing a crucial role in coordinating the synthesis of anthocyanin and proanthocyanidin. It works in tandem with their respective transcriptional activators, VviMYBA1/2 and VviMYBPA1, to maintain an equilibrium of flavonoids. We have discovered a miPEP encoded by miR166c that appears to target VviMYBC2-L1. We conducted experiments to test the hypothesis that silencing this transcriptional repressor through miPEP166c would stimulate the synthesis of anthocyanins and proanthocyanidins. Our transcriptional analyses by qPCR revealed that the application of exogenous miPEP166c to Gamay Fréaux grape berry cells resulted in a significant upregulation in flavonoid transcriptional activators (VviMYBA1/2 and VviMYBPA1) and structural flavonoid genes (VviLDOX and VviDFR), as well as genes involved in the synthesis of proanthocyanidins (VviLAR1 and VviANR) and anthocyanins (VviUFGT1). These findings were supported by the increased enzyme activities of the key enzymes UFGT, LAR, and ANR, which were 2-fold, 14-fold, and 3-fold higher, respectively, in the miPEP166c-treated cells. Ultimately, these changes led to an elevated total content of anthocyanins and proanthocyanidins.

Comprehensive Analysis of Phenolic Constituents, Biological Activities, and Derived Aroma Differences of Penthorum chinense Pursh Leaves after Processing into Green and Black Tea

Penthorum chinense Pursh (Penthoraceae) is a traditional herb used in Miao medical systems that is also processed into foods (e.g., tea products) in China. Different processing methods significantly affect the volatile compounds, phenolic constituents, and biological activities. This study aimed to produce P. chinense green tea leaves (GTL), black tea leaves (BTL), and untreated leaves (UL) to investigate differences in their flavor substances, functional components, antioxidant activity, alcohol dehydrogenase (ADH) activity, and acetaldehyde dehydrogenase (ALDH) activity. The results showed that 63, 56, and 56 volatile compounds were detected in UL, GTL, and BTL, respectively, of which 43 volatile compounds were identified as differential metabolites among them. The total phenolic content (97.13–179.34 mg GAE/g DW), flavonoid content (40.07–71.93 mg RE/g DW), and proanthocyanidin content (54.13–65.91 mg CE/g DW) exhibited similar trends, decreasing in the order of UL &gt; BTL &gt; GTL. Fourteen phenolic compounds were determined, of which gallic acid, (−)-epicatechin, and pinocembrin 7-O-glucoside showed a sharp decrease in content from UL to BTL, while the content of pinocembrin 7-O-(3″-O-galloy-4″, 6″-hexahydroxydiphenoyl)-glucoside and pinocembrin significantly increased. GTL showed better DPPH/ABTS·+ scavenging ability and ferric-reducing ability than UL. The ADH and ALDH activities decreased in the order of GTL &gt; UL &gt; BTL. Therefore, tea products made with P. chinense leaves contained an abundance of functional compounds and showed satisfactory antioxidant and hepatoprotective activities, which are recommended for daily consumption.

Phytochemical analysis and biological activities of various parts of Bulbine natalensis (Baker): A comparative study

Introduction: Bulbine natalensis is a succulent plant native to South Africa, used to treat various skin conditions. The purpose of this investigation was to analyse the phytochemical content, as well as antioxidant and antibacterial activities of various parts of B. natalensis. Methods: Phytochemical screening tests were performed to investigate the presence of ten compounds from B. natalensis methanol extract. Total phenolic, flavonoid, tannin, and proanthocyanidin content assays were followed to determine their concentrations in B. natalensis. The 2,2-diphenyl-1-picrylhydrazyl (DPPH), hydrogen peroxide (H2 O2 ), and iron chelating assays were used to assess the antioxidant activity. To determine the antibacterial properties of B. natalensis against Staphylococcus aureus and Escherichia coli, the agar-well diffusion method was adopted. Results: The phytochemical screening revealed more compounds present in the leaves. The underground stems yielded higher concentrations of total phenolics (1909.2 ± 4.8 mg gallic acid equivalent [GAE]/g), total flavonoids (259.7 ± 27.2 mg quercetin equivalent [QE]/g), and total proanthocyanidins (858.3 ± 1.7 mg catechin equivalent [CE]/g) in comparison to the leaves and roots. The roots showed stronger DPPH (0.36 ± 0.02 mg/mL) and H2 O2 (0.24 ± 0.04 mg/mL) scavenging activities. Only the underground stems and roots showed inhibition against S. aureus with the values of 15.33 ± 0.67 mm and 15.67 ± 0.33 mm, respectively, whereas the leaves displayed the highest inhibition against E. coli (18.33 ± 0.88 mm). Conclusion: The methanolic extracts of B. natalensis leaves, underground stems, and roots possess significant phytochemical content, in conjunction with antioxidant and antibacterial activities.