Abstract Enzymatic browning is one of the essential issues affecting the quality of fresh-cut produce. In this study, we identified a novel, safe, and effective anti-browning agent, 3-mercapto-2-butanol, which can prevent fresh-cut potatoes from browning for 5 d under the concentration of 25 μL L−1 at 5 °C. The inhibitory effect of 3-mercapto-2-butanol was close to sodium bisulfite. 3-Mercapto-2-butanol was further identified as a competitive inhibitor which directly inhibited the activity of polyphenol oxidase (PPO) by enzyme kinetic analysis, and the expression levels of PPO-related genes (POT32 and POT33) were decreased after 3-mercapto-2-butanol treatment. Besides, the concentration of enzymatic browning substrate tyrosine (Tyr) in the potato chips was found significantly higher in 3-mercapto-2-butanol treatment group than in the control group. We speculated that 3-mercapto-2-butanol could reduce the consumption of Tyr by inhibiting the activity of PPO. Our finding not only provided a novel and safe anti-browning agent candidate (3-mercapto-2-butanol) to efficiently solve the browning issue for fresh-cut food products, but also preliminarily revealed its mechanism in browning inhibition.

中文翻译：

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一种抑制鲜切马铃薯褐变的新型抗褐变剂3-巯基-2-丁醇

摘要 酶促褐变是影响鲜切农产品品质的重要问题之一。在本研究中，我们鉴定了一种新型、安全、有效的抗褐变剂3-巯基-2-丁醇，在5°L-1浓度为25 μL的情况下，可防止鲜切马铃薯褐变5 d。 C。3-巯基-2-丁醇的抑制作用与亚硫酸氢钠接近。3-Mercapto-2-butanol 被进一步鉴定为竞争性抑制剂，通过酶动力学分析直接抑制多酚氧化酶 (PPO) 的活性，3-mercapto 后 PPO 相关基因 (POT32 和 POT33) 的表达水平降低-2-丁醇处理。此外，3-巯基-2-丁醇处理组薯片中酶促褐变底物酪氨酸（Tyr）的浓度显着高于对照组。我们推测 3-mercapto-2-butanol 可以通过抑制 PPO 的活性来减少 Tyr 的消耗。我们的发现不仅为有效解决鲜切食品的褐变问题提供了一种新型安全的候选抗褐变剂（3-巯基-2-丁醇），而且初步揭示了其抑制褐变的机制。