摘要
为筛选酱曲中高脂肪酶活力的菌株以提升原料利用率,采用吐温-80和三丁酸甘油酯平板法、对硝基苯酚法及分子生物学鉴定,从酱曲中筛选出产脂肪酶菌株,并对其进行诱变选育,同时将选育菌株应用于酱曲制备.结果显示,筛选菌株JQZ10鉴定为肉葡萄球菌,经紫外诱变后酶活达3.92U/mL,酶活提高了68％,且突变菌株在传代过程中产脂肪酶稳定性好.选育菌株应用于酱曲制备时,成曲感官没有明显的差异,同时添加原始菌株的成曲脂肪酶活性较单一米曲霉提高了48％,添加突变菌株的成曲酶活性提高了77％,且原始菌株和突变菌株之间差异显著(P＜0.05).研究结果表明,酱曲中选育的内源性肉葡萄球菌,可显著提高酱油成曲的脂肪酶活性,为酱油强化发酵和酱曲发酵剂开发提供了理论基础和菌株资源.
Abstract
In order to screen out the strain with high lipase activity in koji to improve raw material utilization,a lipase-producing strain was obtained by tween-80 and tributyrin agar plate,p-nitrophenol method,molecular biology method.In addition,the strain was bred through ultraviolet mutagenesis and applied to make koji.The results showed that the screened strain JQZ10 was identified as Staphylococcus carnosus.After ultraviolet mutagenesis treatment,the lipase activity of this strain reached 3.92 U/mL with a 68％increase.While the lipase production of the mutant strain remained stable during passages.When the bred strains were applied to make koji,different strains of koji do not differ in sensory quality.The koji lipase activity of the added original strain increased by 48％compared with Aspergillus oryzae alone,while the added mutant strain increased by 77％.Furthermore,the difference of lipase activity between the original strain and the mutant strain was significant(P＜0.05).The results indicated that the endogenous S.carnosus screened from koji significantly enhances the lipase activity in koji making,providing a theoretical basis and strain resources for the strengthening of soy sauce fermentation and the development of soy sauce fermentation starter.
基金项目
国家自然科学基金(32101926)
国家自然科学基金(32072198)
广东省自然科学基金(2019A1515110973)
广东省自然科学基金(2021B1515120042)
广东省自然科学基金(2022A1515140021)
广东省自然科学基金(2023A1515012536)
广东省教育厅自然科学研究项目(2021KCXTD034)
广东省教育厅自然科学研究项目(2020ZDZX1046)
广东省教育厅自然科学研究项目(2020ZDZX1029)
广东省教育厅自然科学研究项目(2019KQNCX165)
南昌大学食品科学与技术国家重点实验室开放基金(SKLF-KF-202208)
农业部农业微生物资源收集与保藏重点实验室开放基金(KLMRCP2021-11)
NETL
NSTL
万方数据