Efficient production of androstenedione by repeated batch fermentation in waste cooking oil media through regulating NAD+/NADH ratio and strengthening cell vitality of Mycobacterium neoaurum

Xiuling Zhou; Yang Zhang; Yanbing Shen; Xiao Zhang; Shuangping Xu; Zhihua Shang; Menglei Xia; Min Wang

doi:10.1016/j.biortech.2019.01.144

Efficient production of androstenedione by repeated batch fermentation in waste cooking oil media through regulating NAD⁺/NADH ratio and strengthening cell vitality of Mycobacterium neoaurum

Bioresour Technol. 2019 May:279:209-217. doi: 10.1016/j.biortech.2019.01.144. Epub 2019 Jan 31.

Authors

Xiuling Zhou¹, Yang Zhang², Yanbing Shen³, Xiao Zhang¹, Shuangping Xu¹, Zhihua Shang¹, Menglei Xia¹, Min Wang⁴

Affiliations

¹ Key Laboratory of Industrial Fermentation Microbiology, Ministry of Education, Tianjin Key Laboratory of Industrial Microbiology, College of Biotechnology, Tianjin University of Science & Technology, Tianjin 300457, China.
² Key Laboratory of Industrial Fermentation Microbiology, Ministry of Education, Tianjin Key Laboratory of Industrial Microbiology, College of Biotechnology, Tianjin University of Science & Technology, Tianjin 300457, China; College of Life Science, Liaocheng University, Liaocheng, Shandong 252059, China.
³ Key Laboratory of Industrial Fermentation Microbiology, Ministry of Education, Tianjin Key Laboratory of Industrial Microbiology, College of Biotechnology, Tianjin University of Science & Technology, Tianjin 300457, China; Tianjin Engineering Research Center of Microbial Metabolism and Fermentation Process Control, Tianjin 300457, China. Electronic address: shenyb@tust.edu.cn.
⁴ Key Laboratory of Industrial Fermentation Microbiology, Ministry of Education, Tianjin Key Laboratory of Industrial Microbiology, College of Biotechnology, Tianjin University of Science & Technology, Tianjin 300457, China; Tianjin Engineering Research Center of Microbial Metabolism and Fermentation Process Control, Tianjin 300457, China. Electronic address: minw@tust.edu.cn.

PMID: 30735930
DOI: 10.1016/j.biortech.2019.01.144

Abstract

The bioprocess for producing androstenedione (AD) from phytosterols by using Mycobacterium neoaurum is hindered by nicotinamide adenine dinucleotides (NAD⁺ and NADH) ratio imbalance, insoluble substrate, and lengthy biotransformation period. This study aims to improve the efficiency of AD production through a combined application of cofactor, solvent, and fermentation engineering technologies. Through the enhanced type II NADH dehydrogenase (NDH-II), the NAD⁺/NADH ratio and ATP levels increased; the release of reactive oxygen species decreased by 42.32%, and the cell viability improved by 54.17%. In surfactant-waste cooking oil-water media, the conversion of phytosterol increased from 23.92% to 94.98%. Repeated batch culture successfully reduced the biotransformation period from 30 to 17 days, the productivity was 13.75 times more than the parent strain. This study is the first to improve the productivity of AD by enhancing NDH-II and provides a new strategy to increase the accumulation of NAD⁺-dependent metabolites during biotransformation.

Keywords: Mycobacterium neoaurum; Phytosterol biotransformation; Repeated batch fermentation; Type II NADH dehydrogenase; Waste cooking oil.

MeSH terms

Androstenedione / biosynthesis*
Biotransformation
Cooking*
Fermentation*
Mycobacterium / metabolism*
NAD / metabolism*
Oils / metabolism*
Phytosterols

Substances

Oils
Phytosterols
NAD
Androstenedione