[Objectives]To study the optimum conditions of solid fermentation of natto with antioxidant function as an index.[Methods]Single factor experiment and orthogonal experiment were designed to study the effects of temper...[Objectives]To study the optimum conditions of solid fermentation of natto with antioxidant function as an index.[Methods]Single factor experiment and orthogonal experiment were designed to study the effects of temperature,time,initial pH and inoculum amount on the antioxidant activity of natto solid fermentation.The optimum conditions of natto solid fermentation were determined and the antioxidant ac-tivity of natto extract was compared.[Results]The optimal fermentation conditions were as follows:temperature 32℃,initial pH 7.0,inocu-lation amount 8%,fermentation time 32 h.The hydroxyl radical scavenging rate of natto solid fermentation crude extract was the highest,which was 82.7%.The optimized nato fermentation extract showed stronger scavenging ability for-OH and O,:,and showed obvious dose-effect relationship.ICso was 3.63 and 4.24 mg/mL,respectively,and the scavenging efficiency was 1.3 and 1.9 times higher than that of the unoptimized fermentation extract,respectively.[Conclusions]Natto is rich in nattokinase and other functional factors,and its antioxidant ac-tivity can be improved by optimizing fermentation technology,so that natto products can be widely used,including cosmetic raw materials,nat-to skin care soap,health food and medicine,etc.,and have a broader development prospect.展开更多
Solid-state fermentation has certain advantages in improving the yield of lipopetide, Box-Behnken Design（BBD） was adopted to optimize the producing condition of the antibacterial lipopetide produced by Bacillus natt...Solid-state fermentation has certain advantages in improving the yield of lipopetide, Box-Behnken Design（BBD） was adopted to optimize the producing condition of the antibacterial lipopetide produced by Bacillus natto in this article. The optimal solid state fermentation conditions were obtained： 10 g solid medium（7 g of wheat bran, 3 g of soybean meal） with appropriate inorganic salt（glucose 0.67%,sodium glutamate 0.64%,（NH4）2SO40.15%, K2HPO40.10%）; moisture content 123.78%; inoculation amount 10%; cultivation temperature 36.75 ℃ and cultivation time 72.4 h. The maximum production of lipopetide is 61.76 mg/gds under such conditions. This is the first report on the optimization of lipopeptide fermentation conditions in solid-state fermentation by wheat bran and soybean meal with Bacillus natto NT-6 strain, and will contribute to the development of lipopetide production.展开更多
The word “natto” originated from Japan, which was known as stinky bean, salt bean or silk bean in Chinese folk. Natto contains multiple functional components, including nattokinase, soybean isoflavone, γ-polyglutam...The word “natto” originated from Japan, which was known as stinky bean, salt bean or silk bean in Chinese folk. Natto contains multiple functional components, including nattokinase, soybean isoflavone, γ-polyglutamic acid, vitamin K2, biogenic amines, SOD, small-molecule polypeptide, which has good preventive and curative effects for many diseases, such as cardiovascular and cerebrovascular diseases, hyperlipidemia, hypertension, menopausal symptoms and hypoimmunity. Along with the aging population in the world and China, it is urgent to improve the quality of life. It is necessary to enhance the understanding of natto-related knowledge, expand propaganda power, accept natto consciously and eat natto frequently, which is good for our health and helps our country to build a healthy and harmonious society. This review will descript the development, components, functions and prospects of natto, which help us to offer theoretical basis for promoting natto industry.展开更多
Methionine and lysine are restrictive essential amino acids of livestock, they are also the most attentive indexes in the feed production to carry out the quality control and quality evaluation. Their contents in feed...Methionine and lysine are restrictive essential amino acids of livestock, they are also the most attentive indexes in the feed production to carry out the quality control and quality evaluation. Their contents in feed directly affect livestock protein synthesis. Bacillus natto has excellent probiotic properties. In this experiment, we used the genetic engineering method, fusion PCR technique, to connect methionine-rich gene （zein） from maize endosperm protein with lysine-rich gene （Cflr） from the pepper anther, then the fusion gene was inserted into the expression vector pHT43, and the recombinant plasmid pHT43/zein-Cflr was constructed. The recombinant plasmid was transferred into Bacillus natto, and induced by IPTG for the expression of the fusion gene. We found an apparent band at 40 ku site for the recombinant strain by SDS-PAGE. The contents of methionine and lysine were individually detected with HPLC, the quantities of methionine and lysine in the recombinant strain increased by 18.37% and 24.68% than the wild one, respectively. We also verified the stability of the recombinant bacterium during passaging, and found the stability was 100%. This study provided research-basis for the application of the recombined Bacillus natto as feed additive.展开更多
[Objective] The aim was to optimize the appropriate solid state fermentation(SSF)conditions.[Method] The optimization of solid state fermentation using a mixture substrate of bean curd residue and the marc with Bacill...[Objective] The aim was to optimize the appropriate solid state fermentation(SSF)conditions.[Method] The optimization of solid state fermentation using a mixture substrate of bean curd residue and the marc with Bacillus natto was developed.[Result] The best fermentation condition optimized by the test of single factor and the orthogonal design respectively was mixing ratio of bean curd residue to marc 2∶1,substrate pH value 6,fermentation temperature 39 ℃,inoculum volume 10% and fermentation time 48 h.Under this optimized fermentation condition,the content of crude fiber in the substrate decreased from 107.8 mg/g before SSF to 56.2 mg/g after SSF,and the degeneration rate of crude fiber was 47.87%.[Conclusion] The bean curd residue in its palatability was enormously improved by SSF with Bacillus natto strain,which could be expected to be widely used as raw material of health foodstuff.展开更多
Increasing amounts of antibiotic resistant bacteria have been an emergency problem. Antimicrobial peptides are promising antibiotic alternatives for broad-spectrum antimicrobial activity and nearly no drug resistance....Increasing amounts of antibiotic resistant bacteria have been an emergency problem. Antimicrobial peptides are promising antibiotic alternatives for broad-spectrum antimicrobial activity and nearly no drug resistance. Natto peptide was a new antimicrobial peptide which consisted of 45 amino acids. In this study, to improve the antimicrobial activity of Natto peptide, three repeats of encoding sequences were synthesized and cloned into a pET28 a(+) expression vector, and expressed in Escherichia coli as a soluble protein. Unexpectedly, the purified 3×Natto peptide exhibited antimicrobial activity against Listeria monocytogenes(50 μg/ml) and Salmonella enteriditis(30 μg/ml). Furthermore, the antibacterial spectrum of 3×Natto peptide was not affected by temperature, pH value and proteinase digestion. Taken together, this was the first study proving that 3×Natto peptide could be produced in E. coli as a kind of water dissolve protein, and has great potential for commercial application in the future.展开更多
基金Supported by 2023 Zhanjiang Non-funded Science and Technology Research Plan(2023B01023)2022 University-level Education and Teaching Reform Project of Lingnan Normal University(LingShiJiaoWu2022154).Junxia SONG,bachelor degree,experimenter,research fields:physical geography.
文摘[Objectives]To study the optimum conditions of solid fermentation of natto with antioxidant function as an index.[Methods]Single factor experiment and orthogonal experiment were designed to study the effects of temperature,time,initial pH and inoculum amount on the antioxidant activity of natto solid fermentation.The optimum conditions of natto solid fermentation were determined and the antioxidant ac-tivity of natto extract was compared.[Results]The optimal fermentation conditions were as follows:temperature 32℃,initial pH 7.0,inocu-lation amount 8%,fermentation time 32 h.The hydroxyl radical scavenging rate of natto solid fermentation crude extract was the highest,which was 82.7%.The optimized nato fermentation extract showed stronger scavenging ability for-OH and O,:,and showed obvious dose-effect relationship.ICso was 3.63 and 4.24 mg/mL,respectively,and the scavenging efficiency was 1.3 and 1.9 times higher than that of the unoptimized fermentation extract,respectively.[Conclusions]Natto is rich in nattokinase and other functional factors,and its antioxidant ac-tivity can be improved by optimizing fermentation technology,so that natto products can be widely used,including cosmetic raw materials,nat-to skin care soap,health food and medicine,etc.,and have a broader development prospect.
基金Supported by the Public Research and Capacity Building Program of Guangdong Province(2014B020204005)the Higher Educational Cultivation Program for Major Scientific Research Projects of Guangdong Ocean University(2013050205,2014050203,2013050312)~~
文摘Solid-state fermentation has certain advantages in improving the yield of lipopetide, Box-Behnken Design（BBD） was adopted to optimize the producing condition of the antibacterial lipopetide produced by Bacillus natto in this article. The optimal solid state fermentation conditions were obtained： 10 g solid medium（7 g of wheat bran, 3 g of soybean meal） with appropriate inorganic salt（glucose 0.67%,sodium glutamate 0.64%,（NH4）2SO40.15%, K2HPO40.10%）; moisture content 123.78%; inoculation amount 10%; cultivation temperature 36.75 ℃ and cultivation time 72.4 h. The maximum production of lipopetide is 61.76 mg/gds under such conditions. This is the first report on the optimization of lipopeptide fermentation conditions in solid-state fermentation by wheat bran and soybean meal with Bacillus natto NT-6 strain, and will contribute to the development of lipopetide production.
文摘The word “natto” originated from Japan, which was known as stinky bean, salt bean or silk bean in Chinese folk. Natto contains multiple functional components, including nattokinase, soybean isoflavone, γ-polyglutamic acid, vitamin K2, biogenic amines, SOD, small-molecule polypeptide, which has good preventive and curative effects for many diseases, such as cardiovascular and cerebrovascular diseases, hyperlipidemia, hypertension, menopausal symptoms and hypoimmunity. Along with the aging population in the world and China, it is urgent to improve the quality of life. It is necessary to enhance the understanding of natto-related knowledge, expand propaganda power, accept natto consciously and eat natto frequently, which is good for our health and helps our country to build a healthy and harmonious society. This review will descript the development, components, functions and prospects of natto, which help us to offer theoretical basis for promoting natto industry.
文摘从可食用的纳豆中筛选出一株能够高效降解黄曲霉毒素B1(aflatoxin B1,简称AFB1)的细菌,该细菌的发酵上清液经浓缩后制成的粗酶液对AFB1降解率达到91.4%。对该菌进行了分类地位鉴定并初步研究了粗酶液的酶学性质。结果表明,该菌经生理生化和16S r DNA序列比对鉴定为枯草芽孢杆菌,并命名为Natto3。Natto3的粗酶液降解AFB1的最适培养时间为72h,最适反应温度为37℃,最适p H值是8.5,Zn2+、Mn2+、Mg2+、Cu2+、Li+五种金属离子均会不同程度地抑制降解活性。此外,将该粗酶液添加在被黄曲霉毒素高度污染的花生样品中进行脱毒实验,可使花生中AFB1的浓度从192μg/kg降至43μg/kg。
基金Supported by the Funding of High Technology Project of Ministry of Science and Technology of China(863 Project,2013AA102504-03)
文摘Methionine and lysine are restrictive essential amino acids of livestock, they are also the most attentive indexes in the feed production to carry out the quality control and quality evaluation. Their contents in feed directly affect livestock protein synthesis. Bacillus natto has excellent probiotic properties. In this experiment, we used the genetic engineering method, fusion PCR technique, to connect methionine-rich gene （zein） from maize endosperm protein with lysine-rich gene （Cflr） from the pepper anther, then the fusion gene was inserted into the expression vector pHT43, and the recombinant plasmid pHT43/zein-Cflr was constructed. The recombinant plasmid was transferred into Bacillus natto, and induced by IPTG for the expression of the fusion gene. We found an apparent band at 40 ku site for the recombinant strain by SDS-PAGE. The contents of methionine and lysine were individually detected with HPLC, the quantities of methionine and lysine in the recombinant strain increased by 18.37% and 24.68% than the wild one, respectively. We also verified the stability of the recombinant bacterium during passaging, and found the stability was 100%. This study provided research-basis for the application of the recombined Bacillus natto as feed additive.
文摘[Objective] The aim was to optimize the appropriate solid state fermentation(SSF)conditions.[Method] The optimization of solid state fermentation using a mixture substrate of bean curd residue and the marc with Bacillus natto was developed.[Result] The best fermentation condition optimized by the test of single factor and the orthogonal design respectively was mixing ratio of bean curd residue to marc 2∶1,substrate pH value 6,fermentation temperature 39 ℃,inoculum volume 10% and fermentation time 48 h.Under this optimized fermentation condition,the content of crude fiber in the substrate decreased from 107.8 mg/g before SSF to 56.2 mg/g after SSF,and the degeneration rate of crude fiber was 47.87%.[Conclusion] The bean curd residue in its palatability was enormously improved by SSF with Bacillus natto strain,which could be expected to be widely used as raw material of health foodstuff.
基金Supported by Shandong Provincial Natural Science Foundation(ZR2018PC010)the Doctor Foundation of Binzhou University(2018Y09)Natural Science Program of Binzhou University(BZXYG1811)
文摘Increasing amounts of antibiotic resistant bacteria have been an emergency problem. Antimicrobial peptides are promising antibiotic alternatives for broad-spectrum antimicrobial activity and nearly no drug resistance. Natto peptide was a new antimicrobial peptide which consisted of 45 amino acids. In this study, to improve the antimicrobial activity of Natto peptide, three repeats of encoding sequences were synthesized and cloned into a pET28 a(+) expression vector, and expressed in Escherichia coli as a soluble protein. Unexpectedly, the purified 3×Natto peptide exhibited antimicrobial activity against Listeria monocytogenes(50 μg/ml) and Salmonella enteriditis(30 μg/ml). Furthermore, the antibacterial spectrum of 3×Natto peptide was not affected by temperature, pH value and proteinase digestion. Taken together, this was the first study proving that 3×Natto peptide could be produced in E. coli as a kind of water dissolve protein, and has great potential for commercial application in the future.
