The enzymatic biotransformation effects of tannase/β-glucosidase on phenolic profile, antioxidant capacity, and angiotensin-converting enzyme (ACE) inhibitory activity of extracts from two citrus industry wastes were studied. Hesperidin and hesperetin ACE inhibitory activity were also measured. The major phenolic in crude extracts was hesperidin, whereas it was hesperetin after being biotransformed. Antioxidant capacity and ACE inhibitory activity of enzyme-treated extracts were significantly higher. Citrus pectin residue extracts treated with enzymes (CPRTB) had the highest antioxidant and anti-ACE activities (FRAP = 298±3 μmolTE mg⁻¹, DPPH = 230 ± 10 μmolTE mg⁻¹, IC₅₀ = 0.21 mg mL⁻¹, IE = 100%), and the highest hesperetin content (42.7 mg g⁻¹). Hesperetin standard solution showed higher anti-ACE activity than hesperidin (IE = 82.8–100% and 62–76%, respectively). Despite the lower flavanone concentration in CPRTB compared to the 1000μMhesperetin solution, both had the same anti-ACE activity, suggesting that the bioactivity of citrus extracts is due to the synergism of different phenolic compounds. Enzymatic biotransformation resulted in the production of extracts with increased anti-hypertension activities and might potentially be used to develop value-added products.

研究了鞣酸酶/β-葡萄糖苷酶的酶促生物转化对两种柑橘类工业废品提取物的酚类特征，抗氧化能力和血管紧张素转化酶（ACE）抑制活性的影响。还测量了橙皮苷和橙皮苷ACE的抑制活性。粗提物中的主要酚类成分是橙皮苷，而经过生物转化后，橙皮苷是橙皮苷。经酶处理的提取物的抗氧化能力和ACE抑制活性明显更高。经酶（CPRTB）处理的柑橘果胶渣提取物具有最高的抗氧化和抗ACE活性（FRAP = 298±3μmolTEmg ^-1，DPPH = 230±10μmolTEmg ^-1，IC ₅₀  = 0.21 mg mL ^-1，即IE = 100％）和最高的橙皮素含量（42.7 mg g ^-1）。橙皮素标准溶液显示出比橙皮苷更高的抗ACE活性（IE分别为82.8–100％和62–76％）。尽管CPRTB中的黄烷酮浓度比1000μMhesperetin溶液低，但两者均具有相同的抗ACE活性，这表明柑橘提取物的生物活性是由于不同酚类化合物的协同作用所致。酶促生物转化导致了抗高血压活性增强的提取物的生产，并有可能被用于开发增值产品。