Different drying methods and blanching were investigated as to their effects on antioxidant and oxidase activities of Thunbergia laurifolia leaves. Results showed that oven-drying had the highest degradation of total phenolic content (TPC) and antioxidant activity at >85%, while freeze-drying had the lowest at <20%. However, inactivation of oxidase enzymes by blanching at 100°C resulted in a lesser decrease in TPC for oven-drying at 50 and 100°C (51% and 65%, respectively), indicating the importance of inactivating the oxidase enzymes for lower degradation of phenolics on drying. The high-performance liquid chromatography analysis showed that its major antioxidant, rosmarinic acid, degraded tremendously in the presence of oxidase enzymes, but only degraded slightly upon inactivation of oxidase enzymes. Hence, this work showed that by controlling the enzymatic activity, the preservation of phenolics with specific bioactivity in herbal tea leaves can be achieved. PRACTICAL APPLICATIONS: Thunbergia laurifolia leaves have been frequently consumed in the form of a tea or pill due to its medicinal properties. Processing of fresh herbal plant leaves by drying is required to preserve antioxidant phenolic compounds and quality of the plant leaves. Although the drying effects on the antioxidant properties have been studied, the factors that cause the change in properties have not been investigated in-depth. Controlling the factors that affect the phenolic content can help to preserve the beneficial antioxidants when processing the leaves by drying. The result of this study will be of relevance and beneficial to the herbal tea industry.

译文

研究了不同的干燥方法和热烫对月桂花叶片抗氧化和氧化酶活性的影响。结果表明,烘箱干燥在> 85% 时,总酚含量 (TPC) 和抗氧化活性的降解率最高,而冷冻干燥在 <20% 时最低。然而,通过在100 °C下热烫使氧化酶失活导致用于在50 °C和100 °C下烘箱干燥 (分别为51% 和65%) 的TPC的较小降低,这表明使氧化酶失活对于降低干燥时酚类降解的重要性。高效液相色谱分析表明,其主要抗氧化剂迷迭香酸在氧化酶的存在下降解很大,但在氧化酶失活后仅轻微降解。因此,这项工作表明,通过控制酶活性,可以在草本茶叶中保存具有特定生物活性的酚类。实际应用: 月桂叶由于其药用特性,经常以茶或药丸的形式食用。需要通过干燥处理新鲜草本植物叶片,以保持抗氧化酚类化合物和植物叶片的质量。尽管已经研究了干燥对抗氧化性能的影响,但尚未对导致性能变化的因素进行深入研究。控制影响酚含量的因素可以帮助通过干燥处理叶片时保留有益的抗氧化剂。这项研究的结果将对凉茶行业具有现实意义和有益的意义。

+1
+2
100研值 100研值 ¥99课程
检索文献一次
下载文献一次

去下载>

成功解锁2个技能,为你点赞

《SCI写作十大必备语法》
解决你的SCI语法难题!

技能熟练度+1

视频课《玩转文献检索》
让你成为检索达人!

恭喜完成新手挑战

手机微信扫一扫,添加好友领取

免费领《Endnote文献管理工具+教程》

微信扫码, 免费领取

手机登录

获取验证码
登录