Bovine serum albumin and Triton X-100 greatly increase phosphomonoesterases and arylsulphatase extraction yield from soil

Extraction of arylsulphatase (aryS), acid (acP) and alkaline phosphomonoesterase (alkP) from six different soils using sodium pyrophosphate (0.14 M, pH 7.1) yielded brown extracts displaying enzymatic activity mostly below detection limit. Tris-HCl (50 mM, pH 7.5) gave an extraction yield, on average, lower than 0.5%, but addition of Triton X-100 or bovine serum albumine (BSA) to Tris buffer increased the extraction yield 2-8 times. When both Triton X-100 and BSA were added to the buffer, the extraction yield was more than additive and reached 2-13% for acP, 2-5% for alkP and 3-6% for aryS, depending on the soil. In addition, these extracts were colourless or at most light yellow, showing that besides the high yield enzymes were extracted along with negligible amounts of humic substances.     

洗衣粉中磷含量的测定

[目的]为低磷洗衣粉的生产及应用提供参考资料。[方法]以白猫、雕牌、碧浪、立白、奥妙、超能、奇强、汰渍8种常用洗表粉为材料配制样品液,以抗坏血酸作显色剂,采用分光光度法测定样品液的吸光度,根据磷标准曲线确定各品牌洗衣粉中的磷合量。[结果]建立的磷标准曲线方程为：A=0．2893C＋0．0053（R^2=0．9987）,线性关系良好;所测样品中超能洗衣粉含磷量最高,为21.463U％;其次为奇强洗衣粉,含磷量为17．5113％,汰渍洗衣粉含磷量最低,为0．0250％;37．5％的供试洗衣粉中磷含量超过国家规定标准（1．1％）。[结论]超能和奇强洗衣粉中磷含量严重超标。     

一种光敏杀菌型洗涤剂的研制

以光敏剂竹红菌素作为杀菌剂,用直链烷基苯磺酸盐(LAS)、脂肪醇聚氧乙烯醚硫酸钠(AES)、椰子油二乙醇酰胺(6501)及其他助剂复配光敏杀菌型洗涤剂。采用均匀设计对洗涤剂中3种表面活性剂(LAS、AES和6501)的配比进行优化,采用悬液定量杀菌法测试洗涤剂在不同稀释度和光照处理时间下对大肠杆菌和金黄色葡萄球菌的杀灭对数值。结果表明,表面活性剂的最佳配比为LAS15.5%,AES 4.5%,6501 3.5%。光敏洗涤剂在1∶10稀释度下光照处理3 min或1∶100稀释度下光照处理5 min以上对金黄色葡萄球菌的杀灭对数值KL≥5.00;在所有处理条件下该洗涤剂对大肠杆菌的杀灭对数值均小于5.00。     

蔬菜中残留农药消减方法研究

以菜心为材料,研究了清水、食盐水、洗洁精水溶液分别浸泡菜心15,30,45 min后,对蔬菜残留农药的消减率,经农残快速检测方法(速测卡法)和气谱-质谱联用仪(GC-MS联用仪)法检测,结果表明,1%洗洁精水溶液浸泡15～30min,消减效果最明显,但是经这些溶液浸泡后,蔬菜的食用品质会出现一定程度的下降.     

Adsorption and desorption of monomeric Bt (Bacillus thuringiensis) Cry1Aa toxin on montmorillonite and kaolinite

Genetically modified crops, which produce pesticidal proteins from Bacillus thuringiensis, release the toxins into soils through root exudates and upon decomposition of crop residues. Although the phenomena of gene transfer and emergence of resistance have been well documented, the fate of these toxins in soil has not yet been clearly elucidated. The aim of this study was to elucidate the adsorption and the desorbability of the Cry1Aa Bt insecticidal protein in contact with two sodium-saturated clays: montmorillonite and kaolinite. Because the toxin is released into soil in small quantities, it was assumed that it will be in a monomeric state in solution until it oligomerized on cell membranes. The originality of this study was to focus on the monomeric form of the protein. Specific sample conditions were required to avoid polymerisation. A pH above 6.5 and an ionic strength of at least 150 mM (NaCl) were necessary to keep the protein in solution and in a monomeric state. The adsorption isotherms obtained were of the L-type (low affinity) for both clays and fitted the Langmuir equation. The adsorption maximum of the toxin, calculated by the Langmuir nonlinear regression, decreased with increasing pH from 6.5, which was close to the isoelectric point, to 9. At pH 6.5, the calculated adsorption was 1.7 g g⁻¹ on montmorillonite and 0.04 g g⁻¹ on kaolinite. Desorbability measurements showed that a small fraction of toxin could be desorbed by water (up to 14%) and more by alkaline pH buffers (36 ± 7%), indicating that it was not tightly bound. Numerous surfactants were evaluated and the toxin was found to be easily desorbed from both clays when using zwitterionic and nonionic surfactants such as CHAPS, Triton-X-100, and Tween 20. This finding has important implications for the optimization of detection methods for Bt toxin in soil.     

清洗液对夏白菜中农药残留洗除效果的对比试验

清水、清洁精、无水碳酸钠、臭氧都能不同程度地洗除夏白菜中的敌敌畏、氧乐果、抗蚜威 ,但是洗除效果各不相同。不同的清洗液对同一种农药的清洗效果不同 ;同一种清洗液对不同的农药清洗效果也不相同。试验结果表明 ,安利碟新清洁剂 15 0 0倍液对敌敌畏的清洗效果最好 ;白猫牌清洁精 3 0 0 0倍液对氧乐果的清洗效果最好 ;臭氧水溶液 2 5℃对抗蚜威的清洗效果最好     

几种表面活性剂及营养物对虫生真菌孢子萌发的影响

研究了球孢白僵菌、金龟录僵菌和粉拟青霉在吐温－８０及６种不同的洗衣粉中的分散性及活力。结果表明,３种真菌在这些表面活性剂中的分散指数差异不显著。白僵、绿僵不同浓度的吐温－８０液中的发芽同于不加表面活性剂的对照。多数洗衣粉显著抑制３种真菌的萌发,但白僵菌在０．１％和０．０５％白猫牌无泡超浓缩洗衣粉中发芽 对照差异不显著,在５％和２％葡萄糖液,２％和１％蛋白胨液中,白僵菌孢子在发者发育率最高。     

5个热带豆科牧草洗涤纤维的生育期动态及其施肥响应

为了解不同牧草品种在不同肥力条件下洗涤性纤维的生育期动态变化,采用多因素完全随机区组盆栽试验,测定了热研2号柱花草(S1)(Stylosanthes guianensis(Aubl.)Sw.cv.CIAT184)、圆叶决明CPI34721(S2)(Chamaecrista rotundifolia(Pers.)Greene cv.CPI34721)、圆叶决明CPI86134(S3)(C.rotundifolia cv.CPI86134)、圆叶决明ATF3248(S5)(C.rotundifoliacv.ATF3248)、羽叶决明ATF2217(S5)(C.nictitans(L.)Moench cv.ATF2217)在不施肥(F0)、常量施肥(F1)、加倍施肥(F2)情况下,以及生长期内7月25日(C1)、8月29日(C2)、10月8日(C3)、11月14日(C4)分四次进行刈割的牧草洗涤性纤维含量。结果表明:不同牧草品种的洗涤性纤维含量具有较大差异,中性洗涤纤维(NDF)以S4、S1最高(53.4%、52.7%),S5、S3最低(47.9%、46.9%);酸性洗涤纤维(ADF)和酸性洗涤木质素(ADL)均为S5(23.0%、9.1%)极显著地低于其他4个品种(28.0%~29.0%、11.1%~12.3%)(P<0.01)。施肥试验表明,F2极显著地降低了牧草的ADF含量(P<0.01),对NDF、ADL影响不显著。施肥极显著地降低了牧草在C3刈割期的洗涤纤维含量(P<0.01),F1和F2的NDF、ADF、ADL分别比F0下降6.6、5.4,9.7、6.9,2.6、1.6个百分点,且F2的ADF、ADL含量显著低于F1(P<0.05)。刈割试验表明,5个品种的洗涤纤维均随生长时间持续上升,尤其是ADF平均值从C3期的7.9%急剧上升到C4期的24.6%。采用粗饲料相对值(RFV)评价方法表明,S5的平均RFV值最高(143.7),S4、S1最低(118.2、120.9);S5在C3期的RFV值为116,比S4、S1提高16个分值;施肥可以提高RFV值,且与施肥量成正比。该研究结果可为亚热带地区牧草品种选择、最适刈割期和适宜施肥量的确定提供技术借鉴。     

Detergent solubilised bovine viral diarrhea virus elicits a similar immune response as the inactivated virus

The immune response to two detergent solubilised preparations of Bovine Viral Diarrhea Virus (BVDV) proteins were compared with the response to a chemically inactivated BVDV preparation. The antibody titres were measured with the standard immunofluorescence assay and with a newly developed enzyme linked immunosorbent assay (ELISA). The range of viral protein specificity of the antibodies was compared using SDS-polyacrylamide gel electrophoresis (SDS-PAGE) followed by Western blot analysis. The results clearly demonstrate that the detergent solubilised viral proteins are equally as effective immunogens as the killed BVDV vaccine both in terms of antibody titers and specificity.     

黄海黄杆菌YS-9412-130低温碱性蛋白酶的应用研究Ⅱ.——洗涤剂用包覆型酶的配伍特性与应用效果评价

论述了洗涤剂中的低温碱性蛋白酶的物理和化学特性、去污性能及它与常规洗涤助剂的配伍性。实验结果表明，该包覆型酶最适反应温度为35℃，pH为10。在温度40℃以下、pH5-11范围内均具有良好的稳定性，同时对低温有突出的适应性和抗氧化稳定性；与常规洗涤剂各成分配伍性良好，且低温条件下能有效降解蛋白污渍，主要性能均优于国内外同类产品。