Oryzin (, Aspergillus alkaline proteinase, aspergillopeptidase B, API 21, aspergillopepsin B, aspergillopepsin F, Aspergillus candidus alkaline proteinase, Aspergillus flavus alkaline proteinase, Aspergillus melleus semi-alkaline proteinase, Aspergillus oryzae alkaline proteinase, Aspergillus parasiticus alkaline proteinase, Aspergillus serine proteinase, Aspergillus sydowi alkaline proteinase, Aspergillus soya alkaline proteinase, Aspergillus melleus alkaline proteinase, Aspergillus sulphureus alkaline proteinase, prozyme, P 5380, kyorinase, seaprose S, semi-alkaline protease, sumizyme MP, prozyme 10, onoprose, onoprose SA, protease P, promelase) is an enzyme. This enzyme catalyses the following chemical reaction