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Catechins ar one of the compounds widely found in gambier (Uncaria) and have antioxidant and antibacterial properties. Nanofibers made from polymers and catechins can be applied in wound dressings because they are easily absorbed. Nanofibers are made using the needle-less electrospinning method. Needle-less electrospinning utilizes bubbles that are made as a place for the fiber to come out so that more fiber is produced. The Taguchi method was used as an experimental design with three factors and three levels to get the smallest Diameter. The smallest fiber obtained was 0.1 µm with a voltage, distance, and concentration of 39000V, 5 cm, and 8%, respectively. [ABSTRACT FROM AUTHOR]

The use of natural dyes as textile dyes is increasingly in demand since public awareness of the dangers of synthetic dyes has been increasing. Natural dyes produce a weak color intensity and require repeated dyeing to produce the desired color. This paper studied the effect of chitosan and catechin on the intensity and protection of fabrics in natural dyes from Peristrophe bivalvis expressed by parameters of UV protection factor (UPF) and color difference values (ΔE). The effects were observed between chitosan treatment and a combination of chitosan and catechin treatment of dyed cotton fabric in various concentrations. Cotton fabric treatment was applied before and after the dyeing process, and a combination of both. As a result, as the concentration of chitosan and catechin increased, the color intensity increased, as evidenced by the increase in the ΔE value. The best UPF value was obtained by combining chitosan and catechin on cotton fabric with the concentration of chitosan and catechin, respectively, 15 g/L and 0.5 g/L in the treatment before and after dyeing in a UPF value of 7.22 and a color difference (ΔE) of 36.09. The best lightfastness was obtained by a combination treatment of chitosan and catechin, with the results increased to 3-4 (good). [ABSTRACT FROM AUTHOR]

Polyphenols are aromatic macromolecule micro-nutrients that serve as potential bioactive compounds for treating a broad spectrum of diseases. A systematic literature survey related to polyphenolic compounds that have had anticancer targeted were considered. We have considered repurposing them as potential leads for stomach cancer related proteins. The molecular interaction studies considering docking and molecular dynamic studies were performed with the 57 polyphenolic compounds targeting stomach cancer proteins (pdb id: 1MFG, 3WZD, 3DKC). We found Curcumin, Kaempferol, Catechin, Anthocyanin, Luteolin, Stilbene, Theaflavin, Cyanidin, Naringenin, Trolox, Isoflavone significantly higher binding affinities with targeted proteins (pdb: 3DKC) play major role in Hepatocyte growth factor receptor that induces autophosphorylation of MET lead to downregulation of signals. We discuss the role of repurposing of polyphenolic compounds as novel drug targets in stomach cancer. [ABSTRACT FROM AUTHOR]

The pre-purification heat extraction process separates the catechins and tannins from the impurities present in the gambier. This process uses water as a solvent, at a ratio of 1: 7 to the sample, with a heating extractor, because at a temperature of 70⁰C, catechins and tannin dissolved in water. The solution is then filtered in a hot state. A cold process further extracted the catechins-tannin extract to separate the catechins and tannins, using a cooling extractor, to obtain sediment. A vacuum filter then filters the deposit to get pre-purification catechins with high levels of catechins. At the same time, the tannin passes from filtration and is accommodated in a tannin reservoir. Pre-purified catechins were dried in an oven at 50⁰C, then weighed and measured their catechins level using a spectrophotometer. This study aims to evaluate the prototype of catechins isolation extract from community gambier (Uncaria Gambier) since this extractor is newly designed and newly operated. The evaluation is done by varying the cooling temperature, the extractor cooling time by 3x washing onto the catechins yield. The highest sediment obtained from the 5⁰C temperature variation and 15 hours cooling time was 817.66 grams of 3 kg of dry gambier, at the highest catechins content of 96%. Thus it is concluded that the best performance of cooling extraction on gambier pre purification is still at 48.55%. [ABSTRACT FROM AUTHOR]

Hypercholesterolemia is a main contributing risk factor to cardiovascular disease. Lipase inhibition lessens cholesterol biosynthesis in the liver. Statins are commonly used for hypercholesterolemia treatment. A lot of studies on natural products had been done to investigate potential inhibitors against lipase. Catechin as the essential compound in Uncaria gambir Roxb is conceivable for hypercholesterolemia treatment. This study aims to determine the inhibitory effect of extracts, ethyl acetate fraction, and catechin isolate of Uncaria gambir on lipase activity. Gambir leaf was extracted in water, the fractionation was caried out in ethyl acetate solvent while the isolation of catechin gambier was carried out in ethyl acetate-hexane as the solvent. Phytochemical analysis of extract and isolate was conducted by HPLC. The inhibitory activity of lipase enzymes was carried out using a lipase assay kit by ELISA as well as orlistat as the standard drug. This study has resulted in 68.32%, 92,26% and 96.74% catechin contained in extract, ethyl acetate fraction, and catechin isolate. The in-vitro inhibition assessment of lipase activity indicated that catechin isolate of Uncaria gambir was the most potential inhibitor of lipase (IC50=0.102 mg/mL), here in after ethyl acetate fraction supernatant (IC50=0.386 mg/mL), while extract and orlistat showed relatively less inhibition (IC50=0.680 mg/mL and IC50=0.645 mg/mL). Catechin isolate from Uncaria gambir showed strong inhibition of lipase activity. The outcome showed an equal correlation that the higher catechin, the higher inhibitory of lipase. [ABSTRACT FROM AUTHOR]

Cascara is an infusion beverage produced by coffee bean production. Research on isolation and characterization of catechin, antioxidant activity test and antibacterial test of cascara has been conducted. Isolation of catechin from cascara arabica and robusta was done by maceration with ethanol 95% for 24 hours and column chromatography with acetone-water (1:1) as mobile phase and silica gel as the stationary phase. The isolates were characterized by Thin Layer Chromatography (TLC), UV-Visible and FTIR spectrophotometers. The antioxidant activity of each isolate was measured by DPPH (2,2-diphenyl-1-picrylhydrazyl) method and the antibacterial activity was tested by a disk diffusion method. The UV-Visible and FTIR spectra of the two isolates showed similar spectra with the catechin standard. The radical scavenging activity (RSA) of catechin isolates from cascara arabica and robusta were 78% and 76%, respectively. The antibacterial activity measurement showed that both isolates had relatively moderate-strong antibacterial activity against E.coli and S.aureus. The yield of isolated catechin of arabica, and robusta cascara were 0.02% and 0.01% sequentially. [ABSTRACT FROM AUTHOR]

The purpose of this study was to evaluate the microbial contaminations of gambier (Uncaria gambir Roxb) extract as an antioxidant agent. The microbial contaminations (bacteria, yeasts and moulds) of the extract were analyzed using total plate count (TPC) and total fungus/yeast-mold count (TFC) methods according to SNI ISO 3547.1: 2008. Antioxidant activity was performed using DPPH assay, while water and catechin contents were analyzed based on SNI 01-3391-2000 using thermogravimetry and spectrophotometry methods. All of the analysis was carried out for the extract after being stored in a climatic chamber for 6 months. Results showed that the extract has a strong antioxidant activity with IC50 value of 26.59 µg/ml. Meanwhile, water and catechin contents were approximately 14% and 60%, respectively. Furthermore, it was found that extract is not contaminated by bacteria, yeast and mold with TPC and TFC values are less than 10 CFU/g. Our findings indicated that gambier extract meets with the Indonesian Herbal Pharmacopoeia II and the rules of BPOM 12, 2014 for pharmaceutical use as traditional drug material. [ABSTRACT FROM AUTHOR]

The aim of this study was to extract polyphenols from green tea using different solvents like water, 70% ethanol, 70% methanol and dimethyl formamide. Total polyphenols from various solvents were estimated using Folin- ciocalteu assay and anti-oxidant activity was determined by DPPH radical scavenging activity. Further isolation and purification of the catechin fractions were done by thin layer chromatography and high performance liquid chromatography. [ABSTRACT FROM AUTHOR]

Tea plants were discovered thousands of years ago in South-East Asia, and humankind has been drinking tea for thousands of years due to its medical benefits to prevent and treat a lot of diseases. Tea leaves are specific for their antioxidant capacities due to the presence of a wide range of flavonoid and other phenolic compounds. In this study, spectrophotometric methods were evaluated for determining the total flavonoid contents (TFCs) and ferric reducing antioxidant power (FRAP) in various green and oolong tea products collected in two specific tea-tree plantation regions in the mountainous area (Yen Bai Province-YB, the North) and Central Highland (Da Lat-DL and Lam Ha-LH, Lam Dong Province, the South) of Vietnam. The ultrasound-assisted solid-liquid extraction at 70 °C was employed to prepare the tea extracts with 70% v/v methanol in deionized water as the extraction solvent. Quercetin and trolox were used to build up the calibration curves for TFCs and FRAP, respectively. The results indicated that oolong tea products performed lower TFCs (expressed as milligrams of quercetin equivalents per gram dried weight or mg QE g−1 DW) than green tea (68.06±0.76 to 79.89±0.48 mg QE g−1 DW vs.117.4±1.7 to 244.1±3.9 mg QE g−1 DW) due to the differences in tea plant species and the oxidation levels during the fermentation period. Among the collected dried tea products, the FRAP values (expressed as micromoles of trolox equivalents per gram or µmol TE g−1 DW) were high and followed the decreasing order of YB-Green (2138±23 to 2688±40 µmol TE g−1 DW)>DL-Green (2232±60 to 2349±63 µmol TE g−1 DW)>LH-Oolong (1745.2±5.0 to 1947±45 µmol TE g−1 DW)>DL-Oolong tea products (1551±23 to 1679±25 µmol TE g−1 DW). It could be concluded that green and oolong tea products are rich sources of flavonoids and antioxidants, and the total flavonoid contents could remarkably contribute to the antioxidant capacities (r=0.841). [ABSTRACT FROM AUTHOR]

Lichens are symbiotic photosynthesizing organisms whose thalli are formed by fungi and algae/cyanobacteria. Among the factors that contribute to the ability of a lichen to tolerate harsh environmental conditions is the presence of unique secondary metabolites, such as lichen acids (e.g., usnic and gyrophoric acids), catechins, polysaccharides (including lichenin), and the dark pigment melanin. Melanin is a highly polymeric pigment containing phenolic and indole groups. Information about genes encoding enzymes responsible for melanin synthesis in lichens is very limited. The main aim of the present research was to characterize genes of oxidoreductases involved in melanin synthesis in lichens. It was found that synthesis of eu- and allomelanins in lichens is supported by the activity of genes homologous to those in Ascomycota. Corresponding proteins can be oligomeric or form multidomain structures, and the interplay of these enzymes is a prerequisite for the complex process of melanin synthesis in lichens. [ABSTRACT FROM AUTHOR]

The varieties of potatoes, which tuber flesh has blue colour, are not widely known in our country. However, the interest of such kind of potatoes due to their antioxidant compounds: polyphenols (anthocyanin, leucoanthocyanin, catechin) and vitamin C, is rapidly increasing. The aim of the study was determine the content of the main antioxidant compounds and the total water-soluble antioxidant content of potato tubers with blue flesh. Varieties of potatoes such as 'Blue Congo' and 'Vitelotte', which flesh of the tuber had blue colour, have been investigated. Research results showed that the amounts of anthocyanins and leucoanthocyanins were substantially higher in 'Vitelotte' potato tubers. Catechins content essentially 1.7 times higher was in 'Blue Congo' potato tubers than in 'Vitelotte'. The amount of vitamin C and the total water-soluble antioxidant content of potato tubers of both genotypes was similar, significant differences were not identified. [ABSTRACT FROM AUTHOR]

The varieties of potatoes, which tuber flesh has blue colour, are not widely known in our country. However, the interest of such kind of potatoes due to their antioxidant compounds: polyphenols (anthocyanin, leucoanthocyanin, catechin) and vitamin C, is rapidly increasing. The aim of the study was determine the content of the main antioxidant compounds and the total water-soluble antioxidant content of potato tubers with blue flesh. Varieties of potatoes such as 'Blue Congo' and 'Vitelotte', which flesh of the tuber had blue colour, have been investigated. Research results showed that the amounts of anthocyanins and leucoanthocyanins were substantially higher in 'Vitelotte' potato tubers. Catechins content essentially 1.7 times higher was in 'Blue Congo' potato tubers than in 'Vitelotte'. The amount of vitamin C and the total water-soluble antioxidant content of potato tubers of both genotypes was similar, significant differences were not identified. [ABSTRACT FROM AUTHOR]

Catechin is an antioxidant polyphenol abundant in green tea and exhibits biological and pharmacological properties. Several studies have demonstrated the long term consumption of catechin prevents dyslipidemia, improves the cerebral blood flow and reduces the inflammatory response and the neuronal damage during cerebral ischemia. The aim of the present study was to assess the in vivo dose-dependent effects of catechin on rat pial microcirculation during hypoperfusion and reperfusion injury. Male Wistar rats were anesthetized with alpha-chloralose (50 mg/Kg b.w. intraperitoneally administered), tracheotomized and intubated. Pial microcirculation of male Wistar rats was observed by fluorescence microscopy through a closed cranial window. Hypoperfusion was induced by bilateral common carotid artery occlusion (BCCAo) for 30 min; thereafter, pial microcirculation was observed for 60 min. Arterioles were classified according to Strahler's ordering scheme. Arteriolar diameter was determined by computer assisted-method as well as permeability increase, leukocyte adhesion, perfused capillary length (PCL) and capillary red blood cell velocity (VRBC). Neuronal damage was evaluated by TTC staining. Catechin (2-4 mg/kg b.w.) or L-N5-(1-Iminoethyl) Ornithine Hydrochloride (L-NIO: 15 mg/Kg b.w.) prior to catechin were intravenously administered before BCCAo and at beginning of reperfusion. In ischemic rats, BCCAo caused decrease in order 2 arteriole diameter, reduced by 13.7 ± 2.0 % of baseline at the end of reperfusion (RE). Microvascular permeability and leukocyte adhesion were marked. PCL and VRBC decreased at RE. At the end of BCCAo, catechin dose-dependently reverted order 2 arteriolar diameter decrease, causing vasodilation at RE. Microvascular leakage and leukocyte adhesion were prevented as well as the cortex and striatum neuronal loss in both hemispheres at RE. L-NIO prior to catechin abolished the catechin-induced effects. Western blotting showed that endothelial nitric oxide synthase (eNOS) protein concentration significantly increased in rats treated with cathechin at RE. In conclusion, catechin administration prevents pial microvascular damage induced by hypoperfusion and reperfusion reducing vasoconstriction, microvascular permeability, leukocyte adhesion, capillary blockade and neuronal loss. It is reasonable to suggest that catechin's effects are mainly due to nitric oxide release and to free radical scavenger activity. [ABSTRACT FROM AUTHOR]

Background: Obesity is a major risk factor for the development of chronic diseases and mortality. At the cellular level, increasing number and size of adipocytes diferentiated from preadipocytes characterized the obesity. Excess intake of sugars and lipids causes obesity, but certain food components have been reported to reduce the risk of obesity. Catechins, the active constituent of green tea has been regarded beneficial as an anti-obesity. Our previous study has showed that catechins from green tea GMB4 clone inhibited differentiation of preadipocytes, reduced PPARy and increased the adiponectinn level in preadipocytes culture (Ratnawati et al, 2011) and EGCG also decreased C/EBPα and leptin (Ratnawati et al, 2012). Therefore in this study, we investigated the effect of catechins on the positive and negative regulators of lipogenesis and adipogenesis; ROR-α and C/EBP-α. Method: This study is done in primary cultured of preadipocyte with 4 groups of treatment : (1) control, (2) treated with catechins 5 µM, (3) treated with catechins 10 µM and (4) treated with catechins 30 µM. 2 days post confluence, cell were induce to differentiate into adipocyte with IBMX, DEX and insulin. On days 3 during differentiation, cells were treated with catechins for 24 hour. Cells then harvested and measurement of ROR-α and C/EBP-α were done by ELISA and Immunocytochemistry. Results: In this study we found that catechins significantly reduced the expression of C/EBP-α by 20%, 24% dan 26,43%. . We found that ROR-α expression increased, but not reach statistical significance. Conclusion: This results suggested that catechins at least in part inhibit adipogenesis through C/EBP-α. Studies are needed to see whether higher doses of catechins will exert further increase on ROR- expression and/or its activity. [ABSTRACT FROM AUTHOR]