Development of a Cell Suspension Culture System for Promoting Alkaloid and Vinca Alkaloid Biosynthesis Using Endophytic Fungi Isolated from Local Catharanthus roseus.

Tran My Linh,Ninh Thi Ngoc,Phan Thi Hong Thao,Ninh Khac Ban,Nguyen Chi Mai,Nguyen Tuong Van,Pham Thi Hoe

doi:10.3390/plants10040672

Abstract

Cell and tissue cultures of Catharanthus roseus have been studied extensively as an alternative strategy to improve the production of valuable secondary metabolites. The purpose of this study was to produce C. roseus callus and suspension cell biomass of good quality and quantity to improve the total alkaloids and bis-indole alkaloids. The young stem derived-callus of C. roseus variety Quang Ninh (QN) was grown on MS medium supplemented with 1.5 mg/L 2,4-dichlorophenoxyacetic acid (2,4-D) plus 1.5 mg/L kinetin, and the growth rate increased by 67-fold after 20 days. The optimal conditions for maintaining the cell suspension culture were 150 mg/50 mL cell inoculum, a medium pH of 5.5 and a culture temperature of 25 °C. The low alkaloid content in the culture was compensated for by using endophytic fungi isolated from local C. roseus. Cell extracts of endophytic fungi—identified as Fusarium solani RN1 and Chaetomium funicola RN3—were found to significantly promote alkaloid accumulation. This elicitation also stimulated the accumulation of a tested bis-indole alkaloid, vinblastine. The findings are important for investigating the effects of fungal elicitors on the biosynthesis of vinblastine and vincristine, as well as other terpenoid indole alkaloids (TIAs), in C. roseus QN cell suspension cultures.

Highlights

Published: 31 March 2021Catharanthus roseus is well known as a medicinal plant of the Apocynaceae family that is rich in indole alkaloids
With indole-3-acetic acid (IAA), all of the explants expanded at the cut ends of the stem fragments, but they gradually died without forming calli
This phenomenon was reported by Smetanska [28], who found that the synthesis of secondary metabolites in cell cultures was affected differently from that in plants and depended on environmental conditions

Summary

Introduction

Catharanthus roseus is well known as a medicinal plant of the Apocynaceae family that is rich in indole alkaloids. Among the 130 terpenoid indole alkaloids (TIAs) produced by the plant, bis-indole alkaloids—vincristine and vinblastine—were the first natural agents to be clinically used in the chemotherapeutic treatment of several cancers [1,2,3]. Their concentrations in C. roseus plants are extremely low (0.0003–0.0004% of the dry weight of leaves), making it difficult to meet market demand [4]. A culture medium supplemented with mannitol and sucrose was found to stimulate the synthesis of total alkaloids as well

Objectives

Methods

Results

Discussion

Conclusion