Graduate School of Agriculture, Kyoto University, Kitashirakawa-oiwakecho, Sakyo-ku, Kyoto, Japan.
Product Development Division, Kagome Co., Ltd., 1-24-11 Nihonbashi-Kakigaracho, Chuo-ku, Tokyo, Japan.
Biosci Biotechnol Biochem. 2023 May 19;87(6):663-671. doi: 10.1093/bbb/zbad031.
α-Tomatine is a steroidal glycoalkaloid in tomato plants and degrades with ripening. The aglycone form, tomatidine, is reported to have beneficial effects. In this study, the ability of food-related microorganisms to produce tomatidine from α-tomatine was evaluated. A total of 11 strains of Aspergillus species belonging to the section Nigri exhibited tomatinase activity, and Aspergillus luchuensis JCM 22302 was selected for optimization due to its high activity in its mycelia, conidia, and non-mycotoxin-producing property. Next, using A. luchuensis JCM22302 conidia, the highest yield was obtained in a 24-h reaction with 50 m m of acetic acid-sodium acetate buffer (pH 5.5) at 37 °C. Similar to the tomato pathogen Fusarium oxysporum f. lyceopersici, the time course analysis suggested that A. luchuensis JCM 22302 removed the entire sugar moiety in a single step. Future research will focus on utilizing conidia for large-scale tomatidine production because of their high tolerance and manageability.
α-茄碱是番茄植物中的一种甾体糖苷生物碱，会随着成熟而降解。其糖苷形式，茄啶，据报道具有有益的作用。在这项研究中，评估了与食品相关的微生物将α-茄碱转化为茄啶的能力。属于黑曲霉组的 11 株黑曲霉属菌株表现出茄碱酶活性，由于其菌丝、分生孢子和非产毒素特性，选择了 Aspergillus luchuensis JCM 22302 进行优化。接下来，使用 A. luchuensis JCM22302 分生孢子，在 37°C 下，50 m m 乙酸-醋酸钠缓冲液（pH 5.5）中反应 24 小时，可获得最高产量。与番茄病原体尖孢镰刀菌 f. lycopersici 相似，时程分析表明 A. luchuensis JCM 22302 可以一步去除整个糖基部分。未来的研究将集中利用分生孢子进行大规模的茄啶生产，因为它们具有较高的耐受性和可管理性。
