Study on Optimizing Nutrition and Fermentation Conditions for Compound &amp;lt;i&amp;gt;Bacillus spp.&amp;lt;/i&amp;gt;

Yanyan Li,Yong Yang,Wenhao Li,Changjun Wang,Lin Wang,Yuxiang Xu,Xihong Li,Jun Yu

doi:10.4236/ajmb.2019.92007

Abstract

In order to improve the spore yield of compound Bacillus spp. (B. amyloliquefaciens, B. laterosporus and B. megaterium), the effects of nutrient conditions including carbon source, nitrogen source, mineral salt and fermentation conditions including the inoculum age, inoculation amount, loading volume of liquid and initial pH on the spore yield were studied. The results indicated that the optimized medium was glucoses 20 g/L, soybean meal 30.0 g/L, K2HPO4 1.0 g/L; fermentation temperature is 37℃, the inoculum age 12 h, initial pH 7.0, 2% inoculation amount, loading volume of liquid 20 mL/250 mL. Under the optimized conditions of culture medium and fermentation for compound Bacillus spp., spore yield was 10.24 times more than the initial medium, and the spore formation rate reached more than 90%.

Highlights

Bacillus spp., which has broad spectrum antibacterial activity and strong resistance to stress, is applied abundantly to scientific research and practical production
The results indicated that the optimized medium was glucoses 20 g/L, soybean meal 30.0 g/L, K2HPO4 1.0 g/L; fermentation temperature is 37 ̊C, the inoculum age 12 h, initial pH 7.0, 2% inoculation amount, loading volume of liquid 20 mL/250 mL
With analysis of different carbon sources, glucose is optimal for the growth of compound Bacillus spp

Summary

Introduction

Bacillus spp., which has broad spectrum antibacterial activity and strong resistance to stress, is applied abundantly to scientific research and practical production. It colonizes in plant rhizosphere, body surface, roots and stems, competes with pathogens for nutrients around the plant, and secretes antibacterial substances to inhibit the growth of pathogenic bacteria, achieving the purpose of prevention and control [2]. The suitable medium formula and culture conditions can significantly increase the biomass of the strain or the yield of the spore, and reduce the production cost. It could provide scientific basis for large-scale production of microbial fertilizer through the optimization of the medium. Based on the initial culture medium, the optimal fermentation medium and conditions of compound Bacillus spp. were determined by single factor experiments and orthogonal experiments to lay the foundation for further large-scale application

Methods

Results

Conclusion