Following the procedures described in the literature, we prepared four kinds of wheat-
qu (koji). Two kinds of
Shen-qu were made by kneading a blend of roasted wheat with either the extract from cocklebur leaves or water. Two kinds of
He-dong-shen-qu were made by kneading a blend of roasted wheat, steamed one, and nonheated one (6: 3: 1) with either the extract from white mulberry,
Gosyuyu, cocklebur and mugwort leaves or water. We investigated the number of bacteria and the growth of molds in those kind of
qu and antimicrobial properties of the extract from plant leaves. It was found that
Shen-qu and
He-dong-shen-qu, both prepared with the extract from the respective plant leaves, had 10
8-10
9CFU bacteria/g ·
qu, while those prepared with water instead of the extract, had 10
11CFU bacteria/g ·
qu. Measuring glucosamine in those
qu as the index of the growth of molds,
Shen-qu and
He-dong-shen-qu, prepared with either water or the respective plant extract, showed 4, 000-4, 800 μg glucosamine/g ·
qu, indicating that the respective extract from the plant leaves didn't inhibit the growth of the molds in each
qu. In the paper disk test, extract from cocklebur leaves showed zones of inhibition against
Bacillus species isolated from the
Shen qu, type culture of
B. subtilis, B. cereus, B. firmus, B. licheniformis, B. pumilus, B. sphacricus, Pichia anomala and
Pichia pastoris, but didn't against
Saccharomyces cerceisiae, Aspcoillus orvzae, niger, four species of
Rhizopus including
R. oryzae and lactic acid bacteria, all of which are important microorganisms for making fermented alcohol beverages.
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