Studies on the interaction of p-phenylene diamine with phospholipids

In vitro studies on the interaction of phospholipids with p-phenylene diamine, a major component of hair dyes, were undertaken. Thin layer and molecular sieving chromatography along with phosphorus estimation and spectral characterization suggested the possibility of p-phenylene diamine and its biotransformation products combining with lipophilic biomolecules.     

Studies on the dermal toxicity of p-phenylene diamine

Single dermal application of p-phenylene diamine in guinea-pigs caused pathomorphological lesions over a period of 24 h which later disappeared. Lipid peroxidation activity of skin homogenate showed significant inhibition, whereas superoxide dismutase was unaffected. Histamine content increased initially but showed drastic reduction during recovery. The significance of the data in the potential dermal toxicity of hair dyes is discussed.     

未干聚对苯二甲酰对苯二胺纤维的染色工艺

采用未干的聚对苯二甲酰对苯二胺（PPTA）纤维,分别用阳离子染料和分散染料对其进行染色,探讨纤维含水率、染色温度、染料种类和用量对纤维染色性能的影响。结果表明：相比于干燥的PPTA纤维,用未干的PPTA纤维进行染色,可明显提高纤维的上染率和K/S值;染色纤维具有较高的耐皂洗色牢度和耐摩擦色牢度;同时,染色后不会影响纤维原有的力学性能。     

不同提取方法对灰树花呈味物质释放的影响

目的：研究不同处理方法（酶解、高压蒸煮及闪式高速提取器处理）对灰树花呈味物质释放的影响。方法：采用高效液相色谱法分析可溶性糖、有机酸、游离氨基酸含量和分子质量分布,采用电子舌分析灰树花呈味物质的呈味特性,采用主成分分析（principal component analysis,PCA）法对不同提取方法制备的产物进行统计分析。结果：和原液相比,所有的处理方式样品可溶性糖的总量都显著性降低（P＜0.05）,尤其采用闪式高速提取处理后的高压蒸煮制备液降低最多;相反,有机酸总量在处理后都呈现显著性增加（P＜0.05）,且在经过闪式高速提取器处理后呈一定程度增加;两种酶解作用后样品的游离氨基酸总量都有所增加,高压蒸煮样品的游离氨基酸总量减少,复合酶酶解制备液的鲜味氨基酸、甜味氨基酸以及苦味氨基酸含量均显著增加（P＜0.05）;两种酶解制备液肽分子质量分布中小于3 000 Da的组分含量最多,经过闪式高速提取后其含量减少,说明闪式高速提取不利于游离氨基酸的提取。PCA分析发现无论酶解还是高压蒸煮处理,味感及呈味物质都与原样存在明显差异,闪式高速提取处理后其味感及呈味物质也发生了明显改变。结论：灰树花的呈味特性与其特定的呈味物质关系密切,而呈味物质的高效制备取决于提取方法,本研究可为后续灰树花调味品的开发和呈味肽的制备提供理论指导。     

Application of polyamidoamine dendrimer in reactive dyeing of cotton

Cotton is dyed very extensively using reactive dyes. Conventionally, reactive dyeing requires voluminous amount of electrolyte and alkali for dyeing of cellulosic fibres like cotton. But the consumption of electrolyte for reactive dyeing of cellulosic textiles increases the pollution load in the textile wastewater. Moreover, there is a possibility of reactive dye hydrolysis in presence of alkali which is detrimental but unavoidable. Therefore, an attempt has been made to eliminate the use of electrolyte and alkali by modifying the cotton substrate with different generations of PAMAM (polyamidoamine) dendrimer using exhaust and continuous method of application. Subsequently, dyeing was carried out by exhaust method without using electrolyte and alkali. The dyed samples were tested for wash fastness, light fastness and rubbing fastness. Colour strength in terms of K/S was also assessed. The results were comparable to those for dyeing obtained by conventional exhaust method. Therefore, the proposed method demonstrates a promising alternative to the conventional dyeing method by completely eliminating electrolyte and alkali.     

漂白残液酶解处理对活性染料染色的影响

为了缩短棉针织物前处理和染色时间,针对过氧化氢酶酶解和染色同浴处理造成的染色不稳定问题,研究在过氧化氢酶处理棉针织物漂白残液后的酶解液中进行活性染料同浴染色的可行性,与常规分浴工艺作比较;考察H2O2的不同残余浓度对单一和拼混活性染料色光的影响。结果表明:残余H2O2对活性嫩黄4-GL、活性红B-3BF、活性深蓝B-2GLN的染色效果影响较大,而对其余活性染料影响较小;在酶解、染色同浴工艺中发现,通过采用软水、减少重金属离子含量、适当添加电解质和染料用量等方法,有助于提高酶解、染色同浴工艺的染色效果。     

Investigation of human exposure to triclocarban after showering and preliminary evaluation of its biological effects

The antibacterial soap additive triclocarban (TCC) is widely used in personal care products. TCC has a high environmental persistence. We developed and validated a sensitive online solid-phase extraction-LC-MS/MS method to rapidly analyze TCC and its major metabolites in urine and other biological samples to assess human exposure. We measured human urine concentrations 0-72 h after showering with a commercial bar soap containing 0.6% TCC. The major route of renal elimination was excretion as N-glucuronides. The absorption was estimated at 0.6% of the 70±15 mg of TCC in the soap used. The TCC-N-glucuronide urine concentration varied widely among the subjects, and continuous daily use of the soap led to steady state levels of excretion. In order to assess potential biological effects arising from this exposure, we screened TCC for the inhibition of human enzymes in vitro. We demonstrate that TCC is a potent inhibitor of the enzyme soluble epoxide hydrolase (sEH), whereas TCC's major metabolites lack strong inhibitory activity. Topical administration of TCC at similar levels to rats in a preliminary in vivo study, however, failed to alter plasma biomarkers of sEH activity. Overall the analytical strategy described here revealed that use of TCC soap causes exposure levels that warrant further evaluation.     

啤酒中浑浊物质的鉴定

该研究意在建立啤酒浑浊物质鉴定方法体系。试验中采用直接镜检法、染色镜检法、酸碱溶解法、酶解法、理化分析法对悬浮型浑浊、大颗粒浑浊、雾状浑浊这3种不同类型的啤酒浑浊进行了鉴定。经过实践检验,悬浮型的浑浊物质,可以采用直接镜检法和染色镜检法进行鉴定。大颗粒的浑浊物质可以采用直接镜检法、酸碱溶解法、理化分析法进行鉴定。雾状浑浊物质可采用直接镜检法,酶解法对其进行鉴定。上述鉴定方法体系能区分绝大部分啤酒浑浊物质。     

电子束辐照对涤纶染色性能的影响

使用不同剂量电子束对涤纶织物进行辐照处理,研究了涤纶织物处理前后结晶度和表面形态的变化,对辐照前后涤纶织物染色,分析辐照对染色性能的影响和色牢度的变化情况。研究表明,100kGy的辐照会造成涤纶结晶度上升,染色速率下降,但最终的染色K/S值增加;200kGy辐照会造成涤纶结晶度下降,染色速率上升,但最终K/S下降;400kGy辐照会造成涤纶表面粗糙化,染色K/S上升。     

A non-aqueous dyeing process of reactive dye on cotton

Based on previous work, the feasible method for dyeing cotton with reactive dye in dye/decamethyl cyclopentasiloxane (D5) suspension system was re-established by increasing the system stability using selected surfactants, and taking the color depth (K/S value) as the evaluation index, the dyeing process parameters such as temperature, dyeing duration, pick-up ratio of alkali solution on fabric, as well as the alkali concentration were optimized further for setting up dyeing conditions. The dyeing results produced by new method showed that the dye uptake could reach nearly 100% without any salt as accelerating agent. Since just a little water was used in the process, hydrolysis of reactive dyes was restrained, fixing rate was increased, and the apparent color depth of the dyed sample was much better than traditional water bath dyeing. The washing fastness and rubbing fastness of samples were satisfactory.     

Stability of the insecticide cypermethrin during tomato processing and implications for endocrine activity

The thermal and pH stabilities of cypermethrin during food processing were investigated using tomato as a model food system and high-performance liquid chromatography as the analytical method. Cypermethrin was thermally unstable in aqueous conditions, where the hydrolysis of the pesticide was accelerated by heat. The mean proportion remaining after heating cypermethrin in water for 10 min was 66%, falling to 27% after 1 h. Similarly, thermal processing of canned tomatoes caused cypermethrin to degrade, with remaining levels in the final product ranging from 30 to 60% of the original. Cypermethrin was unstable at extreme pHs, with acid hydrolysis occurring faster than alkaline hydrolysis in phosphate buffers. The acidity of tomato paste (pH 4.3) caused cypermethrin levels to decrease by 30% within 12 days at 5°C. The studies indicate that cypermethrin residues are likely to degrade by hydrolysis during food processing, thus reducing the exposure of consumers to cypermethrin. 3-Phenoxybenzaldehyde, a hydrolysis breakdown product of cypermethrin, was detected in the tomato paste and from the heating of cypermethrin in water at 100°C. There is concern that the risk of breakdown products in terms of endocrine activity is unknown since in vitro studies reported that cypermethrin breakdown products display endocrine activity.     

非水介质-微水体系中活性染料的水解和键合性能

为探明非水介质-微水体系中活性染料与棉纤维的键合性能及伴随的染料水解行为,应用高效液相色谱法(HPLC)结合实际染色法,研究非水介质-微水溶液体系中、模拟反应体系中及实际染色中活性染料的水解特性、与醇羟基的键合特性及对棉纤维的上染特性。结果表明：染料在非水介质-微水溶液体系中的水解主要取决于染料与水的相对浓度、pH值和温度;在非水介质-微水的甲醇模拟反应体系中,活性染料的醇解率显著高于常规水浴体系,提高pH值使醇解率与水解率之比有所提高,而提高温度则使该比例明显下降;在非水介质-微水的染色体系中,较宽的pH值和温度范围内活性染料染棉均具有超高的上染率;非水介质-微水体系染色拟采用较高pH值和较低温度工艺,以利节水低碳生产。     

Excretion of carbohydrates by rats fed legume seeds

A study of sugars excretion in rats after feeding with diets containing various raffinose content (0, 4, 8 and 12%) and cooked leguminous seeds (soybean, peas and beans) has been performed. It was noted, that feeding with raffinose-containing diet has no effect on sugars level in urine during 10 days of experiment. Feeding with the diets containing 8 and 12% raffinose caused highly increased excretion of this sugar and its metabolites in faeces after first 24 h. After next few days of experiment in despite of high raffinose content in diets the level of raffinose excretion in the faeces came back to the initial one. In the case of leguminous seeds feeding of rats increased excretion of sugars in faeces was observed also after 20-24 h, and was maintained on the same level during 10 days of experiment. The ratio of excreted to consumed sugars was limited to 2-5% only. It is presumed that there were stachyose and verbascose metabolites, previously identified in leguminous seeds.     

含咪唑结构高强高模聚酰亚胺纤维的制备及其结构与性能

为增强聚酰亚胺纤维的力学性能,促进其在复合材料领域的应用,基于高性能聚合物纤维的结构设计,将杂环二胺单体5-氨基-2- (对氨基苯基)苯并咪唑引入到3,3',4,4'-联苯四羧酸二酐和对苯二胺的聚酰亚胺刚性骨架中得到纺丝溶液,通过干法纺丝技术制备得到聚酰亚胺纤维,研究了纤维化学结构和聚集态结构与纤维力学性能的关系,并系统评价了纤维的热性能和抗紫外光辐照性能。结果表明:聚酰亚胺纤维的拉伸强度和初始模量分别达到4.04、130 GPa,这得益于其聚合物分子链沿纤维轴向的高度取向性及分子链间形成的氢键作用;其玻璃化转变温度和热质量损失10%时温度分别为324、587 ℃,经168 h 紫外光辐照后,拉伸强度保持率为92%,具有良好的耐热性和优异的抗紫外光辐照性能。     

Total determination of residual flutolanil and its metabolites in livestock products and seafood using liquid chromatography-tandem mass spectrometry

ABSTRACT

We have developed a simple and sensitive LC-MS/MS analytical method for the determination of residual flutolanil and its principal metabolites, including α,α,α-trifluoro-3′-hydroxy-o-toluanilide (M-4) and its conjugates, in livestock and seafood products. Both flutolanil and its metabolites contain the 2-(trifluoromethyl)benzoic acid (2-TFMBA) moiety. In this method, flutolanil and its metabolites are converted to 2-TFMBA by hydrolysis. The method involves direct hydrolysis with sodium hydroxide at 200°C, acidification, partitioning into a mixture of ethyl acetate-n-hexane (1:9, v/v), clean-up using a strong anion exchange cartridge (InertSep SAX), and then quantification using LC-MS/MS. The optimal conditions for the complete hydrolysis of flutolanil to 2-TFMBA are an incubation time of 6 h and a temperature of 200°C. The developed method was evaluated using seven types of food: bovine samples of muscle, fat, liver and milk, as well as egg, eel, and freshwater clam. Samples were spiked both at 0.01 mg/kg and at the Japanese maximum residue limit (MRL) established for each food type. The validation results show excellent recoveries (88–107%) and precision (< 10%) for flutolanil and M-4. The limit of quantification (S/N ≥ 10) of the developed method is 0.01 mg/kg. The developed method is applicable to the definition of residual flutolanil for animal-based food commodities and MRLs established by the Codex Alimentarius, and will be useful for the regulatory monitoring of residual flutolanil and its metabolites in food products.     

Enhancement of γ-aminobutyric acid content in shells of passion fruit (Passiflora edulis) under anoxic vacuum conditions

Passiflora edulis, commonly known as passion fruit, is a popular all-weather fruit eaten fresh or processed. Its shells, which currently are mostly discarded as waste and hurt the environment, account for more than half of the passion fruit. The shells contain gamma-aminobutyric acid (GABA) which is the main inhibitory neurotransmitter and has many proven medical values such as antidepressant, anti-anxiety, etc. Many studies have shown that GABA production in plants can be significantly increased by reverse stress. Taking Tainong 1 as a typical passion fruit cultivar, this study explored the optimal anoxic vacuum treatment for increasing the GABA content of passion fruit shells. The content increased to 2139.25 ± 26.69 mg/100 g on day 4 of chill storage after vacuum packing (63.68% higher than the control). The activities of glutamate decarboxylase (GAD) and diamine oxidase (DAO) were significantly higher in the vacuum-treated group than in the control group after 4 days of vacuum-chill storage. On day 5 of vacuum-chill storage, the activities of all measured enzymes decreased except for the increase of GABA transaminase (GABA-T), which was accompanied by a decrease in GABA content. Vacuum treatment and subsequent chill storage increased the content of GABA, thereby increasing functional value of passion fruit shells.     

在助剂作用下山桐子油的软脱胶工艺研究

山桐子油是一种营养及其丰富的食用油,但因含有较多磷脂类胶溶性杂质,容易使其酸败变质,在高温下发黑发苦,降低其品质。采用乙二胺四乙酸二钠为螯合剂,十二烷基磺酸钠为乳化剂和碳酸钠为助剂的软脱胶工艺脱除山桐子油中的胶体物质,考察螯合脱胶剂的体积比、脱胶温度、脱胶时间和离心分离时间对山桐子油脱胶效果的影响,得到山桐子油的最佳脱胶工艺:螯合脱胶剂的体积比为2∶3∶3,脱胶温度为35℃,脱胶时间为10 min,离心分离时间为30 min,在最佳工艺条件下山桐子油的脱胶率达到96.93%。同时,建立的分析方法可有效地测定山桐子油中磷脂含量。与传统脱胶工艺相比,不仅其脱胶率有大幅度的提高,而且脱胶后的山桐子油色泽也更加透明。     

改性活性染料对涤纶织物的紫外光引发接枝染色

为实现涤纶织物的室温短时紫外光接枝生态染色,采用2-甲基-3-丁烯-2-醇单体改性活性染料,在碱处理涤纶的基础上采用紫外光照射接枝改性染料单体。通过核磁共振氢谱（HNMR）、傅里叶变换红外光谱（ATR）、扫描电子显微镜 (SEM) 等测试手段对改性染料和染色前后的涤纶织物的化学结构进行表征。通过测试织物的染色深度、摩擦牢度、透气性能、拉伸性能、刚柔性能等分析涤纶织物染色前后服用性能的变化。结果表明,相比于未处理染色涤纶织物,碱处理涤纶染色织物具有较好的染色深度,色差值ΔE将近14,干摩擦牢度达4级,湿摩擦牢度达3-4级,且拉伸性能、刚性和透气性稍下降。     

活性翠蓝G的染色特性及浸染工艺

结合活性翠蓝G的染色特性，分析了其耐盐析性、上染速率、耐碱水解性的特征，并介绍了活性翠蓝G的染色配伍性。此外，还就溶解方法、色牢度、耐氧漂性、水质、匀染剂的选择等事项进行了探讨，并给出了染色工艺和操作注意事项。     

Physico-chemical and enzymatic studies on acetylated protein isolates from faba beans (Vicia faba L.)

Selected physico-chemical properties of a faba bean protein isolate before and after being acetylated have been investigated using analytical ultracentrifugation, SE- and RP-HPLC, viscometry and hydrophobicity measurements using fluorescence probe techniques. The time course of relative chymotryptic hydrolysis rates was followed by means of the TNBS method and RP-HPLC analysis. The extensive decrease of the 11 S and 7 S protein components of the isolate in favour of a low molecular weight 2 S component after exhaustive acetylation is the proof of the dissociated state of the highly modified derivatives. Both the viscometric measurement and the study of proteolysis breakdown give arguments for a rather unfolded state both of the unmodified and the modified protein isolates. The course of relative chymotryptic hydrolysis rate points to a successive transition from a globular state into a more unfolded one depending on the degree of acetylation. Both the viscometric data and the hydrophobicity measurements revealed a conformational transition at about 60% N-acetylation. This level of modification corresponds to that where a sharp increase of OH-acetylation takes place.