Page 160 - 《广西植物》2023年第6期
P. 160

1 1 4 6                                广  西  植  物                                         43 卷
                    ( 1. Guangxi Key Laboratory of Plant Functional Phytochemicals and Sustainable Utilizationꎬ Guangxi Institute of Botanyꎬ
                          Guangxi Zhuang Autonomous Region and Chinese Academy of Sciencesꎬ Guilin 541006ꎬ Guangxiꎬ Chinaꎻ
                                      2. Guangxi Tea Research Instituteꎬ Guilin 541004ꎬ Guangxiꎬ China )

                 Abstract: To compare the differences in the active componentsꎬ the antioxidant and hypoglycemic activities in vitro
                 between seven different varieties of raw tea water extractsꎬ and to determine the correlation between each ingredient and
                 activityꎬ the contents of total polyphenolsꎬ total flavonoids and tea polysaccharides in the water extracts of raw tea and its
                 infusion were determined. The antioxidant and hypoglycemic activities of raw tea water extracts were evaluated by
                 DPPH scavenging abilityꎬ ORAC value and α ̄glucosidase and α ̄amylase inhibition as indicatorsꎬ and Pearson
                 correlation analysis was performed. The results were as follows: (1) There were significant differences in the contents of
                 water extractꎬ total polyphenolsꎬ total flavonoids and tea polysaccharides among the seven varietiesꎬ while the highest
                 contents were found in Golden tea (53.42%±0.14%)ꎬ Guihong No.4 (40.87% ± 1.09%)ꎬ Yunnan big leaf species
                 (27.17% ± 0.26%) and Fuyun No.6 (2.70% ± 0.02%)ꎬ respectively. (2) There were also significant differences in
                 DPPH scavenging abilities and ORAC values among the seven varietiesꎬ while the varieties showing better antioxidant
                 effects in both evaluation methods were the Liupao group speciesꎬ Guihong No. 4 and Wantian species. ( 3) The
                 inhibitions of α ̄glucosidase and α ̄amylase by the water extracts of seven varieties were significantly stronger than those
                 of acarbose positive control. The varieties showing better hypoglycemic effects in both evaluation methods were Liupao
                 group speciesꎬ Guihong No.4 and Guiqing species. (4)The antioxidant and hypoglycemic activities were all strongly and
                 positively correlated with the contents of total polyphenols and flavonoids. In summaryꎬ raw tea quality of Liupao group
                 speciesꎬ Guihong No. 4ꎬ Wantian species and Guiqing species are betterꎬ among which Liupao group species and
                 Guihong No. 4 have the prospect of developing antioxidant and hypoglycemic functional foodꎻ Wantian species and
                 Guiqing species have the potential of developing antioxidant and hypoglycemic functional food respectively. Total
                 polyphenols and total flavonoids have a great contribution to the in vitro antioxidant and hypoglycemic activities of raw
                 teaꎬ so that attention should be paid to the protection of such components during the further processing and utilization of
                 raw tea. The results of this study provide a scientific basis for the development of Liupao tea products with better
                 antioxidant and hypoglycemic activities in the selection of raw materials and processing methods of raw tea.
                 Key words: different varietiesꎬ raw teaꎬ water extract componentsꎬ antioxidant activityꎬ hypoglycemic activity




                六堡茶为广西特有的传统名茶ꎬ属于黑茶类ꎬ                               随着人们生活水平的提 高 和 饮 食 方 式 的 改
            不仅具有丰富的功能成分和良好的保健功效ꎬ还给                             变ꎬ糖尿病的患病率日益增长且有年轻化趋势( 杨
            人“红、浓、陈、醇” 的感官体验ꎬ越来越受到消费者                          玉洁等ꎬ2021)ꎮ 抗氧化剂是能捕获并中和自由
            青睐(黄敏周等ꎬ2020ꎻ马婉君等ꎬ2020)ꎬ已成为广                       基ꎬ从而保护人体免受自由基损害的一类物质( 张
            西壮族自治区重点支持发展“千亿元茶产业” 中的                            泽生等ꎬ2017)ꎬ能增强机体的抗氧化能力ꎬ是预防
            重要组团(李欣鞠ꎬ2019ꎻ孔妮ꎬ2020)ꎮ 由于六堡茶                      和治疗糖尿病及其并发症的常用物质ꎮ 随着生活
            是以鲜茶叶为原料ꎬ经初制工艺制成毛茶ꎬ在此基                             中诱发自由基产生的辐射增多以及人类对健康越
            础上进一步精制陈化(渥堆发酵)而成ꎬ因此六堡茶                            来越重视ꎬ抗氧化剂已成为食品以及医学领域研
            生产过程中间原料毛茶的品质优劣对六堡茶品质                              究的热点ꎮ 然而ꎬ目前常用的抗氧化剂多为西药ꎬ
            的形成至关重要(马婉君等ꎬ2020)ꎮ 然而ꎬ通过前                         有较多毒副作用ꎬ并且不能有效地控制并发症( 龚
            期市场调研发现ꎬ制作六堡茶所采用的毛茶来源于                             艳振等ꎬ2012)ꎮ 人们更青睐可长期食用、毒副作
            较多的茶树品种且原料质量不一ꎬ从而导致生产的                             用小的天然抗氧化剂ꎬ选择茶产品时ꎬ除了注重口
            六堡茶成品茶质量参差不齐ꎬ严重阻碍了六堡茶产                             感外ꎬ人们也会更多关注它在抗氧化、降血糖方面
            业的发展ꎬ迫切需要评价这些茶树品种之间的毛茶                             的保健功效ꎮ 因此ꎬ开发抗氧化、降血糖活性更好
            品质差异ꎬ有利于六堡茶生产企业准确地选择毛茶                             的六堡茶产品具有广阔的市场前景ꎮ
            中间原料以进一步稳定成品六堡茶的品质ꎮ                                    茶多酚(黄烷醇类、黄酮类、花青素、酚酸)、茶
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