Optimization of ultrasound-assisted dilute acid hydrolysis conditions of tea processing waste

Abstract. Lignocellulosic materials that are the most abundant plant biomass in the world have the potential to become sustainable sources of the produced value added products. Tea processing waste (TPW) is a good lignocellulosic source to produce the value added products from fermentable sugars. Therefore, the present study is undertaken to produce fermentable sugars by using ultrasound-assisted dilute acid hydrolysis of TPW followed by enzymatic hydrolysis. Furthermore, optimization of ultrasound-assisted dilute sulfuric acid (UADA) hydrolysis conditions of TPW was performed by response surface method at maximum power (900 W) for 2 h. Optimized conditions were 50°C, 1:6 (w/v) solid: liquid ratio, and 1% (w/v) dilute acid ratio, which yielded as 20.34 g/L fermentable sugar concentration. In conclusion, ultrasound-assisted dilute acid hydrolysis can be successfully applied for hydrolysis of TPW, which is a favorable carbon source for numerous value-added product productions via microbial fermentation.