In Vitro Production and Exudation of 20-Hydroxymaytenin from <i>Gymnosporia heterophylla</i> (Eckl. and Zeyh.) Loes. Cell Culture

• Main Authors: Thanet Pitakbut, Michael Spiteller, Oliver Kayser
• Format: Article
• Language: English
• Published: MDPI AG 2021-07-01
• Series: Plants
• Subjects: plant cell culture; plant exudate; 20-hydroxymaytenin; <i>Gymnosporia heterophylla</i>
• Online Access: https://www.mdpi.com/2223-7747/10/8/1493

The metabolite 20-Hydroxymaytenin (20-HM) is a member of the quinone-methide pentacyclic triterpenoids (QMTs) group. This metabolite group is present only in Celastraceae plants, and it has shown various biological activities from antioxidant to anticancer properties. However, most QMTs metabolites including 20-HM cannot be synthesized in a laboratory. Therefore, we optimized a plant tissue culture protocol and examined the potential of <i>Gymnosporia heterophylla</i> (synonym. <i>Maytenus heterophylla</i>) to produce 20-HM in an in vitro experiment. For the first time, we reported the optimum callus induction medium with a high percentage success rate of 82% from the combination of 1 mg/L indole-3-butyric acid and 5 mg/L naphthalene acetic acid. Later, our cell suspension culture cultivated in the optimum medium provided approximately 0.35 mg/g fresh weight of 20-HM. This concentration is roughly 87.5 times higher than a concentration of 20-HM presenting in <i>Elaeodendron croceum</i> (Celastraceae) leaves. In addition, we also found that 20-HM presented in a cultivation medium, suggesting that <i>G. heterophylla</i> cells secreted 20-HM as an exudate in our experiment. Noticeably, 20-HM was missing when <i>Penicillium</i> cf. <i>olsonii</i> occurred in the medium. These findings hint at an antifungal property of 20-HM.