Biotransformation of Shrimp Wastes by Bacillus subtilis OKF04 and Evaluation of Growth Promoting Effect in Crop Planting

In this study, we proposed a reliable and sustainable technique for the clean utilization of shrimp wastes, which can yield a solid inoculant of Bacillus subtilis OKF04 containing micronutrients at low cost without the risk of contamination. Study of the culture conditions revealed that the head of shrimp Litopenaus vannamei and the wheat bran acted as suitable substrates for the growth of B. subtilis OKF04. With 60% initial moisture content, 30 °C culture temperature, and 5 % inoculation amount, followed by 48 hours of fermentation and 0.5% soluble starch added during the drying process (50°C for 6 h), a solid B. subtilis OKF04 inoculant with a spore amount of 2.4×10 10 CFUg −1 and a high amino acid content was obtained. The solid B. subtilis OKF04 inoculant was applied to cultivate pakchoi under pot experiment. As the result, of adding to, the size of stems and leaves, nutritional composition, and physiological activity of pakchoi were significantly ( P