Project description:Purple coloured tea shoot clones have gained interest due to high content of anthocyanins in addition to catechins. Transcript expression of genes encoding anthocyanidin reductase (ANR), dihydroflavonol-4-reductase (DFR), anthocyanidin synthase (ANS), flavonol synthase (FLS) and leucoantho cyanidin reductase (LAR) enzymes in three new purple shoot tea clones compared with normal tea clone showed higher expression of CsDFR, CsANR, CsANS and lower expression of CsFLS and CsLAR in purple shoot clones compared to normal clone. Expression pattern supported high content of anthocyanins in purple tea. Four anthocyanins (AN1-4) were isolated and characterized by UPLC-ESI-QToF-MS/MS from IHBT 269 clone which recorded highest total anthocyanins content. Cyanidin-3-O-β-d-(6-(E)-coumaroyl) glucopyranoside (AN2) showed highest in vitro antioxidant activity (IC50 DPPH = 25.27 ± 0.02 μg/mL and IC50 ABTS = 10.71 ± 0.01 μg/mL). Anticancer and immunostimulatory activities of cyanidin-3-glucoside (AN1), cyanidin-3-O-β-d-(6-(E)-coumaroyl) glucopyranoside (AN2), delphinidin-3-O-β-d-(6-(E)-coumaroyl) glucopyranoside (AN3), cyanidin-3-O-(2-O-β-xylopyranosyl-6-O-acetyl)-β-glucopyranoside (AN4) and crude anthocyanin extract (AN5) showed high therapeutic perspective. Anthocyanins AN1-4 and crude extract AN5 showed cytotoxicity on C-6 cancer cells and high relative fluorescence units (RFU) at 200 μg/mL suggesting promising apoptosis induction activity as well as influential immunostimulatory potential. Observations demonstrate potential of purple anthocyanins enriched tea clone for exploitation as a nutraceutical product.
Project description:Tea is the first most popular beverage worldwide and is available in several selections such as black (fully oxidized), Oolong (partially oxidized) and green (non-oxidized), in addition to purple tea, an emerging variety derived from the same tea plant (Camellia sinensis). This study investigated purple tea leaves (non-oxidized) and flakes (water extractable) to thoroughly identify their composition of anthocyanins and catechins and to study the effect of a water extraction process on their compositional properties in comparison with green tea. Anthocyanin and catechin compounds were separated and quantified using UPLC, and their identity was confirmed using LC-MS/MS in positive and negative ionization modes. Delphinidin was the principal anthocyaninidin in purple tea, while cyanidin came in second. The major anthocyanin pigments in purple tea were delphinidin-coumaroyl-hexoside followed by delphinidin-3-galactoside and cyanidin-coumaroyl-hexoside. The water extraction process resulted in substantial reductions in anthocyanins in purple tea flakes. There were no anthocyanin compounds detected in green tea samples. Both purple and green tea types were rich in catechins, with green tea containing higher concentrations than purple tea. The main catechin in purple or green tea was epigallocatechin gallate (EGCG) followed by either epicatechin gallate (ECG) or epigallocatechin (EGC), subject to tea type. The extraction process increased the concentration of catechins in both purple and green tea flakes. The results suggest that purple tea holds promise in making healthy brews, natural colorants and antioxidants and/or functional ingredients for beverages, cosmetics and healthcare industries due to its high content of anthocyanins and catechins.
Project description:Almost all flowers of the tea plant (Camellia sinensis) are white, which has caused few researchers to pay attention to anthocyanin accumulation and color changing in tea flowers. A new purple-leaf cultivar, Baitang purple tea (BTP) was discovered in the Baitang Mountains of Guangdong, whose flowers are naturally pink, and can provide an opportunity to understand anthocyanin metabolic networks and flower color development in tea flowers. In the present study, twelve anthocyanin components were identified in the pink tea flowers, namely cyanidin O-syringic acid, petunidin 3-O-glucoside, pelargonidin 3-O-beta-d-glucoside, which marks the first time these compounds have been found in the tea flowers. The presence of these anthocyanins seem most likely to be the reason for the pink coloration of the flowers. Twenty-one differentially expressed genes (DEGs) involved in anthocyanin pathway were identified using KEGG pathway functional enrichment, and ten of these DEG's screened using venn and KEGG functional enrichment analysis during five subsequent stages of flower development. By comparing DEGs and their expression levels across multiple flower development stages, we found that anthocyanin biosynthesis and accumulation in BTP flowers mainly occurred between the third and fourth stages (BTP3 to BTP4). Particularly, during the period of peak anthocyanin synthesis 17 structural genes were upregulated, and four structural genes were downregulated only. Ultimately, eight critical genes were identified using weighted gene co-expression network analysis (WGCNA), which were found to have direct impact on biosynthesis and accumulation of three flavonoid compounds, namely cyanidin 3-O-glucoside, petunidin 3-O-glucoside and epicatechin gallate. These results provide useful information about the molecular mechanisms of coloration in rare pink tea flower of anthocyanin-rich tea, enriching the gene resource and guiding further research on anthocyanin accumulation in purple tea.
Project description:Finding promising purple tea germplasm that would target new tea products for diversification and value addition boost the tea industry's economic growth. Accordingly, 10 tea germplasm viz. TRA St. 817, TRA St. 293, TRA St. 400, TRA 177/3, TRA 376/2, TRA 376/3, TRA 427/7, TRA P7, TRA P8, and TV1 were evaluated in terms of gas exchange parameters, multiplication performance, and biochemical markers such as chlorophyll, carotenoids, and anthocyanin content, which are related to the purple tea quality. The investigated gas exchange and biochemical parameters revealed significant differences. Germplasm TRA St.817 was physiologically more efficient (24.7 μmol m-2 s-1), followed by TRA St. 293, exhibiting the highest net photosynthesis, water use efficiency (19.02 μmol mmol-1), carboxylation efficiency (0.73), chlorophyll fluorescence or photochemical efficiency of PSII (0.754) and mesophyll efficiency (ci/gs ratio: 2.54). Net photosynthesis was positively correlated with water use efficiency, carboxylation efficiency, mesophyll efficiency, and photochemical efficiency of PSII (r = 0.965**, 0.937**, 0.857**, 0.867**; P = 0.05), respectively, but negatively correlated with the transpiration ratio (r = -0.878**; P = 0.05) based on Pearson correlation analysis. The total anthocyanin content (4764.19 μg.g-1 fresh leaf weight) and carotenoid content (3.825 mg.g-1 fresh leaf weight) were highest in the TRA St.817 germplasm, followed by germplasm TRA St. 293 (2926.18 μg.g-1 FW). In contrast, total chlorophyll content was significantly low (1.779 mg.g-1 fresh weight), which is very suitable for manufacturing purple tea. The highest carotenoid concentration in TRA St. 817 was 3.825 mg.g-1 FW, followed by TRA P8 (3.475 mg.g-1 FW), favoring the formation of more volatile flavor constituents. The promising germplasm, TRA St 817, has a multiplication success rate of 91.4% through cleft grafting. The outcome reveals that TRA St.817 is a promising germplasm that can be used to make speciality teas, i.e., purple tea.
Project description:Given the rise of morbidity and mortality caused by Klebsiella pneumoniae (KP), the increasing number of strains resistant to antibiotics, and the emergence of hypervirulent Klebsiella pneumonia, treatment of KP infection becomes difficult; thus, novel drugs are necessary for treatment. Anthocyanins, or natural flavonoids, have an extensive effect against bacterial infection. However, few studies on anti-KP are identified. Here, we evaluated the therapeutic effect of purple sweet potato anthocyanins (PSPAs) on KP, containing 98.7% delphinidin 3-sambubioside. Results showed that KP-infected mice after PSPAs treatment manifested decreased mortality, weakened lung injury, dampened inflammatory responses, and reduced bacterial systemic dissemination in vivo. In Vitro, PSPAs significantly suppressed pyroptosis and restricted NLRP3 inflammasome activation in alveolar macrophages infected with KP. As for the mechanism, PSPAs promote mitophagy by recruiting Parkin to the mitochondria. PSPAs-conferred mitophagy increased mitochondrial membrane potential and decreased mitochondrial reactive oxygen species and mitochondrial DNA, resulting in impaired NLRP3 inflammasome activation. In addition, the promotion of mitophagy by PSPAs required the Nrf2 signaling pathway. Collectively, these findings suggest that PSPAs are a potential option for the treatment of KP infection.
Project description:Plant secondary metabolites such as terpenes, phenolics, glycosides, and alkaloids play various functional roles including pigmentation, foliar and floral volatile synthesis, hormonal regulation, and direct and indirect defenses. Among these, phenolic compounds are commonly found in plants, but vary in the distribution of their specific compounds among plant families. Polyphenols, including anthocyanins and tannins, are widely distributed and have been well documented for their roles- primarily in plant pigmentation and also in plant defenses. However, commercialization of such compounds for use in insect pest management is severely hampered by expensive, inefficient, and time-consuming extraction protocols. Using a recently developed inexpensive and easy extraction method using the byproducts of pigmented (purple) corn processing, we examined whether the crude pericarp extract rich in polyphenols can affect the growth and development of tobacco hornworm (Manduca sexta L.) caterpillars. Our findings show that purple corn pericarp extract negatively affected M. sexta egg hatching and larval mass gain and prolonged developmental time compared to regular yellow corn extract or an artificial control diet. We also found that these effects were more severe during the early stages of caterpillar development. These results conclusively demonstrate that purple corn pericarp, an inexpensive by-product of the corn milling industry, is a valuable product with excellent potential as an insect antifeedant.
Project description:Black bean is a source of anthocyanins and other phenolic compounds that are associated with health benefits. This work aimed to optimize the extraction and determine the stability and biological potential of black bean anthocyanin-rich extracts recovered by supercritical fluid extraction (SFE) and pressurized liquid extraction (PLE). The highest concentration of anthocyanins and total phenolic compounds were recovered with SFE using 300 bar, 60 °C and co-solvent ethanol/distilled water (50/50, v/v). Eleven non-colored phenolic compounds were identified in SFE extract using Ultra performance liquid chromatography - Electrospray ionization-Quadrupole -Time of flight - Mass spectrometry (UPLC-ESI-QToF-MS/MS). Myricetin, syringic acid, rutin hydrate and chlorogenic acid presented the highest relative area among identified compounds. Compared to leaching extraction, SFE extracts showed a similar storage stability at 4, 25 and 32 °C (p < 0.05), but with a higher antioxidant potential (2,2-diphenyl-1-picryl-hydrazil (DPPH) IC50: 0.078 ± 0.01; 2,2'-azino-bis(3-ethylbenzothiazoline)-6-sulfonic acid (ABTS) IC50: 0.161 ± 0.03) and antidiabetic potential (α-amylase IC50: 124.76 ± 12.97; α-glucosidase IC50: 31.30 ± 0.84; dipeptidyl peptidase-IV IC50: 0.195 ± 0.01). SFE extraction is an efficient method to obtain anthocyanins and other phenolic compounds with exceptional biological potential.
Project description:Hypercholesterolemia is one of the modifiable and primary risk factors for cardiovascular diseases (CVD). Emerging evidence suggests the stimulation of transintestinal cholesterol excretion (TICE), the nonbiliary cholesterol excretion, using natural products can be an effective way to reduce CVD. Bilberry (Vaccinium myrtillus L.) has been reported to have cardioprotective effects by ameliorating oxidative stress, inflammation, and dyslipidemia. However, the role of bilberry in intestinal cholesterol metabolism is not well understood. To examine the effects of bilberry in intestinal cholesterol metabolism, we measured the genes for cholesterol flux and de novo synthesis in anthocyanin-rich bilberry extract (BE)-treated Caco-2 cells. BE significantly decreased the genes for cholesterol absorption, i.e., Niemann-Pick C1 Like 1 and ATP-binding cassette transporter A1 (ABCA1). In contrast, BE significantly upregulated ABCG8, the apical transporter for cholesterol. There was a significant induction of low-density lipoprotein receptors, with a concomitant increase in cellular uptake of cholesterol in BE-treated cells. The expression of genes for lipogenesis and sirtuins was altered by BE treatment. In the present study, BE altered the genes for cholesterol flux from basolateral to the apical membrane of enterocytes, potentially stimulating TICE. These results support the potential of BE in the prevention of hypercholesterolemia.
Project description:Cardioprotective potential of anthocyanin rich red cabbage extract (ARCE) was assessed in H2O2 treated rat neonatal cardiomyoblasts (H9c2 cells) and isoproterenol (ISO) induced rodent model of myocardial infarction. H2O2 treated H9c2 cells recorded cytotoxicity (48-50%) and apoptosis (57.3%), the same were reduced in presence of ARCE (7-10% & 12.3% respectively). Rats pretreated with ARCE for 30 days followed by ISO treatment recorded favourable heart: body weight ratio as compared to ISO treated group. Also, the mRNA levels of enzymatic antioxidants (sod and catalase) and apoptotic genes (bax and bcl-2) in ARCE+ISO treated group were similar to the control group suggesting that ARCE pretreatment prevents ISO induced depletion of enzymatic antioxidants and apoptosis. Histoarchitecture of ventricular tissue of ISO treated group was marked by infracted areas (10%) and derangement of myocardium whereas, ARCE+ISO treated group (4.5%) recorded results comparable to control (0%). ARCE+ISO treated group accounted for upregulation of caveolin-3 and SERCA2a expression as compared to the ISO treated group implying towards ARCE mediated reduction in membrane damage and calcium imbalance. Molecular docking scores and LigPlot analysis of cyanidin-3-glucoside (-8.7 Kcal/mol) and delphinidin-3-glucoside (-8.5 Kcal/mol) showed stable hydrophobic and electrostatic interactions with β1 adrenergic receptor. Overall this study elucidates the mechanism of ARCE mediated prevention of experimentally induced myocardial damage.