Optimization of the re-extraction process of ethanol from catechin components from Korean green tea extract

Abstract

The purpose of this study was to determine the optimum re-extraction conditions of ethanol from catechin in Korean green tea (Camellia sinensis L.) using response surface methodology (RSM). The experiments were carried out according to a five level and two variable central composite design (CCD). The two independent variables were solvent ratio to sample content (1, 4, 7, 10, 13 mL/g) and extraction temperature (-20, -10, 0, 10, 20℃) on the dependent variables including yield, epigallocatechin (EGC), epicathchin (EC), epigallocatechingallate (EGCG), epicatechingallate (ECG), total catechin and caffeine. ANOVA results showed that Coefficients of determination (R 2 ) of estimated models for dependent variables were ranged from 0.9054~0.9778, while R 2 of caffeine were estimated 0.8770. The optimum ranges for the maximized extraction including yield, EGC, EC, EGCG, ECG, caffeine and total catechin were 4.5~7.5 mL/g in ratio of ethanol to sample and -8~8℃ in extraction temperature. The actual values of yield, EGC, EC, EGCG, ECG, caffeine and total catechin, respectively, at the optimized conditions were 35.02%, 13.31%, 3.978%, 19.11%, 4.29%, 5.30% and 40.68% Key words：green tea, Camella sinensis L., optimization, response surface methodology, catechin 서 론 1) 녹차는 차나무(Camella sinensis L.)에서 어린잎을 채취하 여 가공한 것으로 전 세계적으로 많이 음용되고 있는 기호 식품중의 하나로 다양한 생리활성 효과도 있는 것으로 알려 져 있다(1). 녹차의 성분은 채엽 시기(2), 품종(3), 재배환경 (4) 등에 따라 차이가 난다고 알려져 있으며 특히 녹차에 함유되어있는 카테킨 화합물의 양이나 질은 pH, 온도, 효소 처리 등의 추출조건이나 방법에 따라서 크게 좌우된다고 보고되고 있다(5). 차는 당, 유기산, 질소화합물, polyphenol,

Low-Molecular-Weight Hydrolysate from Black Goat Extract Had Antioxidative and Anti-Inflammatory Effects in Macrophage Cells via Inhibition of MAPKs and NF-κB Pathways

“…Glutamic acid and glycine were identifed as the two major amino acids in both APT6 and APT6 < 3 kDa, with concentrations ranging from 12.57 to 13.23 g/100 g and 9.94 to 11.18 g/100 g, respectively. Tis fnding is consistent with previous studies that have reported glutamic acid and glycine as the predominant amino acids in other BGEs [14,17]. Aspartic acid, proline, alanine, leucine, lysine, and arginine were also abundant in APT6 and APT6 < 3 kDa.…”

“…Following ultrafltration with a 3 kDa cutof, threonine, leucine, tyrosine, and phenylalanine were increased, whereas aspartic acid, glycine, and cysteine were decreased. Te essential amino acid (EAA) content of APT6 and APT6 < 3 kDa was found to be 32.96% and 35%, respectively, which surpassed the EAA content of black goat meat extract (23.9%) [17] and veal meat and bone hydrolysate (21.82%) [18]. However, the reported EAA content of chicken meat hydrolysate (44.5%) [19] exceeds that of APT6 and APT6 < 3 kDa.…”