本研究旨在开发一种从绿茶废物(GTW)中提取生物活性化合物的有效方法,以实现其在食品工业中的潜在应用。GTW,这是在绿茶产品的收获和加工过程中产生的,占全球每年近100万吨的损失。值得注意的是,这种废物富含多酚化合物,尤其是儿茶素,以其显著的健康益处而闻名。我们评估了使用热水提取(HWE)从GTW中提取儿茶素的优化,超声辅助提取(阿联酋),和不同样品与溶剂比(1:100、1:50和1:20w/v)的乙醇提取(EthE)技术。HWE和UAE的提取温度均设置为80°C;但是,对于Ethe来说,温度在70℃时略低,坚持乙醇的沸点。高效液相色谱法用于通过定量各种儿茶素来确定提取效率(即,儿茶素,表儿茶素[EC],表儿茶素没食子酸酯[心电图],表没食子儿茶素[EGC],和表没食子儿茶素没食子酸酯[EGCG])。就单个儿茶素的浓度而言,发现EC是检测到的最高浓度,在所有提取技术和溶剂比例中,范围为30.58±1.17至37.95±0.84mg/L,其次是EGCG(9.71±1.40-20.99±1.11mg/L),EGC+C(7.95±0.66-12.58±0.56mg/L),心电图(1.85±0.71-6.05±0.06mg/L)。DPPH(2,2-二苯基-1-苯基-肼基)自由基测定的结果表明,HWE在所有比率下都表现出最高的提取效率,范围从61.41±1.00到70.36±1.47mg/L。与UAE(24.16%±0.95%)和EthE(22.59%±0.26%)相比,1:50的比例表现出最高的提取率(25.98%±0.75%)。此外,这种提取方法(即,HWE)产生最高的总儿茶素和%DPPH减少。因此,HWE是从GTW中提取儿茶素的最有效方法,强调其在食品制造业中提高废物价值的潜力。
This study aimed to develop an efficient method for the extraction of bioactive compounds from green tea waste (GTW) toward its potential application in the food industry. GTW, which is generated during the harvesting and processing of green tea products, accounts for a global annual loss of nearly 1 million tonnes. Notably, this waste is rich in polyphenolic compounds, particularly
catechins, which are renowned for their significant health benefits. We assessed the optimization of catechin extraction from GTW employing hot water extraction (HWE), ultrasound-assisted extraction (UAE), and ethanol extraction (EthE) techniques at different sample-to-solvent ratios (1:100, 1:50, and 1:20 w/v). The extraction temperature was set at 80°C for both HWE and UAE; however, for EthE, the temperature was slightly lower at 70°C, adhering to the boiling point of ethanol. High-performance liquid chromatography was used to determine the extraction efficiency by quantifying various
catechins (i.e., catechin, epicatechin [EC], epicatechin gallate [ECG], epigallocatechin [EGC], and epigallocatechin gallate [EGCG]). In terms of the concentration for individual
catechins, EC was found to be the highest concentration detected, ranging from 30.58 ± 1.17 to 37.95 ± 0.84 mg/L in all extraction techniques and ratios of solvents, followed by EGCG (9.71 ± 1.40-20.99 ± 1.11 mg/L), EGC + C (7.95 ± 0.66-12.58 ± 0.56 mg/L), and ECG (1.85 ± 0.71-6.05 ± 0.06 mg/L). The findings of DPPH (2,2-diphenyl-1-picryl-hydrazyl) free radical assay illustrated that HWE demonstrated the highest extraction efficiency at all ratios, ranging from 61.41 ± 1.00 to 70.36 ± 1.47 mg/L. The 1:50 ratio exhibited the highest extraction yield (25.98% ± 0.75%) compared to UAE (24.16% ± 0.95%) and EthE (22.59% ± 0.26%). Moreover, this method of extraction (i.e., HWE) produced the highest total
catechins and %DPPH reduction. Consequently, HWE was the most efficient method for extracting
catechins from GTW, underscoring its potential for valorizing waste within the food manufacturing industry.