Fermentation by Rhizopus spp. has been used as a traditional medicine for treating various inflammatory diseases. Allergic asthma is a chronic respiratory disease that is caused by an exaggerated immune response. This study was conducted to ascertain the anti-inflammatory effects of Rhizopus spp. fermentation extract (RU) on a mouse model of ovalbumin (OVA)-induced asthma. The animals were intraperitoneally injected OVA on day 1 and 7, followed by OVA intranasal inhalation on days 14 to 18. The animals were treated daily with RU (100 and 200 mg/kg) by oral gavage from day 18 to day 23. RU significantly decreased eosinophilia and the production of inflammatory cytokines and OVA specific immunoglobulin E in animals with asthma, along with reducing airway inflammation and mucus secretion in lung tissue. Histological changes in the lungs and levels of inflammatory mediators of allergic airway inflammation were evaluated. The regulatory effects of RU on type 2 helper T (Th2) cell activation were investigated. RU administration attenuated asthmatic changes such as inflammatory cell infiltration and mucus production, decreased the levels of Th2-related cytokines, and reduced Th2 cell activation. Administration of RU effectively reduced allergic responses in asthmatic mice, which is associated with regulating Th2 cell activation and differentiation. These results indicate that RU can attenuate the respiratory symptoms of asthma.

This study was conducted to determine the influence of culture conditions such as temperature, time, water content, koji-thickness, and agitation on the production of protease by Rhizopus sp. ZB9, isolated from Korean Nuruk, during the preparation of rice koji, which is used in brewing the Korean rice wines, Takju and Yakju. Rice koji was made under different culture conditions, and the proteolytic activity of each koji was tested. The temperature range suitable for the production of protease was 28~32℃. Based on the protease and color, 60 hours of cultivation at 28℃ was shown to produce optimum results. The production of protease increased in proportion to the increase in water content of steamed rice from 25% to 35%. An increase in koji-thickness induced no adverse effects on the production of protease, and agitation during cultivation showed beneficial effects.

This study was conducted to determine the influence of culture conditions such as temperature, time, water content, koji-thickness and agitation on the production of organic acid by Rhizopus sp. ZB9 isolated from Korean Nuruk during the preparation of rice koji, which is used in brewing the Korean rice wines, Takju and Yakju. Rice koji was made under different culture conditions, and the acidity of each koji was tested. The temperature range suitable for the production of organic acid was 28～32℃, and 36～48 hours of cultivation at that temperature range seemed to produce the optimum results. The production of organic acid increased in proportion to the increase in water content of steamed rice from 25% to 60%. An increase in koji-thickness induced no adverse effects on the production of organic acid, and agitation-work during cultivation showed very beneficial effects.