Screening and characterization of fungal cultures for a milk-clotting enzyme for use in an oriental style dairy product

SummaryThe aim of this work was to develop new oriental style dairy products coagulated with culture filtrates from lao-chao, a traditional fermented rice product. The fermenting fungal cultures screened wereRhizopus javanicus, Rhiz. oryzae, Rhiz. chinensis, Rhiz. oligosporus, Aspergillus oryzae, Mucor racemosusand chiu-yao, a commercial starter. All the inocula liquefied a steamed glutinous rice base and produced culture filtrates with both milk-clotting and proteolytic activities. Of the fungal products tested,Rhiz. javanicuswas the most successful, producing a good yield of culture filtrate with the desired milk-clotting activity, and the resultant yogurt-like product was more acceptable to consumers than any except that from chiu-yao. The firmness was less acceptable, but this could be improved by using mixed pure cultures ofRhiz. javanicusandM. racemosus.

Biocatalytical Transformations, III [1] Regioselective Enzymic Deacetylations of Laevoglucosane Triacetate

Several hydrolytic enzymes (porcine liver esterase, lipase from wheat germ type I, and the lipase from rhizopus javanicus) efficiently deacetylate laevoglucosane triacetate (2) with good regioselectivity into diacetylated laevoglucosane derivatives (3-5).