Hubei Yasen Biotechnology Co.,Ltd, as a high & new technical enterprise of China, focuses on the R&D and producing of microecologics and antibiotic fermentation, is one of the largest manufacture of Acetylisovaleryltylosin tartrate in the worldwide, in addition, is the first company owns Tywasin patent (Patent No. ZL 201010565652.1)in China.

Yasen Biotechnology's plant areas is 55000m2 ,owns modernized GMP production lines, at present, the annual production capacity of Acethlisovalerythylosin tartrate is 40tons, it will be 120tons after production expend. The raw material of Animal macrolide antibiotics is the main product of Yasen Biotechnolgy. doramectin and other three products will be mass production year by year after 2014.