旨在研究连花清瘟药渣和发酵产物的生物学活性,探明自然发酵、优化发酵1(4MYL)和优化发酵2(Y4ML)三种发酵方式对药渣中营养成分的改变以及乙醇提取物和水提取物抑菌效果及抗病毒效果的差异。采用肉汤稀释法测定药渣发酵前后不同提取物...旨在研究连花清瘟药渣和发酵产物的生物学活性,探明自然发酵、优化发酵1(4MYL)和优化发酵2(Y4ML)三种发酵方式对药渣中营养成分的改变以及乙醇提取物和水提取物抑菌效果及抗病毒效果的差异。采用肉汤稀释法测定药渣发酵前后不同提取物对猪副嗜血杆菌(Haemophilus parasuis,HPS)、猪链球菌二型(Streptococcus suis type 2,SS2)、肠毒性大肠杆菌(Enterotoxigenic Escherichia coli,ETEC)3种致病菌菌株的最小抑菌浓度(MIC);以伪狂犬病病毒(Pseudorabies virus,PRV)、猪圆环病毒2型(porcine circovirus type 2,PCV2)、猪繁殖与呼吸综合征病毒(porcine reproductive and respiratory syndrome virus,PRRSV)分别感染非洲绿猴肾细胞(Vero)、非洲绿猴胚胎肾细胞(MARC-145)、猪肾细胞(PK-15),通过荧光显微镜观察细胞形态病变,同时结合实时荧光定量PCR技术进行病毒核酸检测和定量作为药物体外抗病毒效果的评价指标。结果表明,连花清瘟原药渣的乙醇和水提取物对HPS和SS2均表现出抑制作用,但对ETEC无抑制作用;对3种试验病毒均表现出抗病毒活性,但抗病毒活性存在一定区别。发酵后乙醇和水提取物增强了抗菌抗病毒活性,同时对ETEC表现出抑制作用。综上表明,连花清瘟药渣提取物具有不同程度的抗菌、抗病毒作用,能有效抑制猪养殖过程中HPS、SS2等常见的致病菌和病毒,发酵后能增强抗菌和抗病毒效果,具有开发成动物饲料或饲料添加剂的潜力。展开更多
In order to ascertain the effects of atmospheric pressure on developmental characteristics and the stability of AEA(air-entraining agent)solution bubbles,AEA solution experiments and AEA solution bubble experiments we...In order to ascertain the effects of atmospheric pressure on developmental characteristics and the stability of AEA(air-entraining agent)solution bubbles,AEA solution experiments and AEA solution bubble experiments were,respectively,conducted in Peking(50 m,101.2 kPa)and Lhasa(3,650 m,63.1 kPa).Surface tensions and inflection-point concentrations were tested based on AEA solutions,whilst developmental characteristics,thicknesses and elastic coefficients of liquid films were tested based on air bubbles of AEA solutions.The study involved three types of AEAs,which were TM-O,226A,and 226S.The experimental results show that initial sizes of TM-O,226A,and 226S are,respectively,increased by 43.5%,17.5%,and 3.8%.With the decrease of ambient pressure,the drainage rate and the drainage index of AEA solution bubbles increase.Interference experiments show that the liquid film thicknesses of all tested AEA solution bubbles are in micron scales.When the atmospheric pressure decreases from 101.2 to 63.1 kPa,the liquid film thicknesses of three types of AEA solutions decrease in various degrees;and film elasticities at critical thicknesses increase.Liquid film of 226S solution bubbles is the most stable,presenting as a minimum thickness variation.It should be noted that elastic coefficient of liquid film only represents the level at critical thickness,thus it can not be applied as the only evaluating indicator of bubble stability.For a type of AEA,factors affecting the stability of its bubbles under low atmospheric pressure include initial bubbles size,liquid film thickness,liquid film elasticity,ambient temperature,etc.展开更多
文摘旨在研究连花清瘟药渣和发酵产物的生物学活性,探明自然发酵、优化发酵1(4MYL)和优化发酵2(Y4ML)三种发酵方式对药渣中营养成分的改变以及乙醇提取物和水提取物抑菌效果及抗病毒效果的差异。采用肉汤稀释法测定药渣发酵前后不同提取物对猪副嗜血杆菌(Haemophilus parasuis,HPS)、猪链球菌二型(Streptococcus suis type 2,SS2)、肠毒性大肠杆菌(Enterotoxigenic Escherichia coli,ETEC)3种致病菌菌株的最小抑菌浓度(MIC);以伪狂犬病病毒(Pseudorabies virus,PRV)、猪圆环病毒2型(porcine circovirus type 2,PCV2)、猪繁殖与呼吸综合征病毒(porcine reproductive and respiratory syndrome virus,PRRSV)分别感染非洲绿猴肾细胞(Vero)、非洲绿猴胚胎肾细胞(MARC-145)、猪肾细胞(PK-15),通过荧光显微镜观察细胞形态病变,同时结合实时荧光定量PCR技术进行病毒核酸检测和定量作为药物体外抗病毒效果的评价指标。结果表明,连花清瘟原药渣的乙醇和水提取物对HPS和SS2均表现出抑制作用,但对ETEC无抑制作用;对3种试验病毒均表现出抗病毒活性,但抗病毒活性存在一定区别。发酵后乙醇和水提取物增强了抗菌抗病毒活性,同时对ETEC表现出抑制作用。综上表明,连花清瘟药渣提取物具有不同程度的抗菌、抗病毒作用,能有效抑制猪养殖过程中HPS、SS2等常见的致病菌和病毒,发酵后能增强抗菌和抗病毒效果,具有开发成动物饲料或饲料添加剂的潜力。
基金Funded by the National Natural Science Foundation of China(Nos.52178428,52178427,and 52308454)the Science and Technology Project of Tibet Department of Transportation(No.XZJTKJ[2020]04)。
文摘In order to ascertain the effects of atmospheric pressure on developmental characteristics and the stability of AEA(air-entraining agent)solution bubbles,AEA solution experiments and AEA solution bubble experiments were,respectively,conducted in Peking(50 m,101.2 kPa)and Lhasa(3,650 m,63.1 kPa).Surface tensions and inflection-point concentrations were tested based on AEA solutions,whilst developmental characteristics,thicknesses and elastic coefficients of liquid films were tested based on air bubbles of AEA solutions.The study involved three types of AEAs,which were TM-O,226A,and 226S.The experimental results show that initial sizes of TM-O,226A,and 226S are,respectively,increased by 43.5%,17.5%,and 3.8%.With the decrease of ambient pressure,the drainage rate and the drainage index of AEA solution bubbles increase.Interference experiments show that the liquid film thicknesses of all tested AEA solution bubbles are in micron scales.When the atmospheric pressure decreases from 101.2 to 63.1 kPa,the liquid film thicknesses of three types of AEA solutions decrease in various degrees;and film elasticities at critical thicknesses increase.Liquid film of 226S solution bubbles is the most stable,presenting as a minimum thickness variation.It should be noted that elastic coefficient of liquid film only represents the level at critical thickness,thus it can not be applied as the only evaluating indicator of bubble stability.For a type of AEA,factors affecting the stability of its bubbles under low atmospheric pressure include initial bubbles size,liquid film thickness,liquid film elasticity,ambient temperature,etc.
