文章以实验室自制的胺化松香基树脂(ethylenediamine rosin-based resin,EDAR)为吸附材料,通过静态吸附实验测试其对牛奶中青霉素类抗生素的去除效果,采用液相色谱-串联质谱法进行浓度测定,并研究了树脂的重复使用能力,实验结果表明,EDAR对牛奶中的阿莫西林和青霉素G都具有一定的吸附效果.EDAR对阿莫西林和青霉素G的等温吸附过程均更符合Langmuir等温吸附模型,动力学过程符合准二级动力学模型.胺化树脂可用作固相萃取柱填料,对牛奶中抗生素的残留检测具有潜在的应用前景.

A method for rapid detection of aerobic plate count in pasteurized cow's milk by impedance method was established.The following relationship between the germ count and the impedance detection time (t) was determined for the calibration equation:y=-0.5923 t+ 9.4172,r=-0.9907,with high reliability,and the authentic detection threshold was 10～107 mL-1,fully meet the requirements of the national food safety standard.The establishment of the sample evaluation criteria could be fast,intuitive evaluation of the milk samples,the fastest 7.46 h could determine whether the sample is qualified,greatly shorten the detection time.Compared with the national standard method,the method was simple,rapid,sensitive,accurate and reliable,and could be used in different periods,sources and acidity of the product,with a wide range of applicability and practicality.

A method for rapid detection of commercial sterility in acid canned food was established by indirect impedance method. The microorganisms which are easily contaminated in acid canned foods, such as Paeni-bacillus polymyxa, Leuconostoc mesenteroides and Hansenula anomala were selected as experimental strains to study of the threshold, applicability, sensitivity, measurement duration and sample volume of canned food of the indirect impedance method. Compared with the national standard method GB 4789.26-2013<National food safety standard Food microbiological examination:Examination of commercial sterility>, the study showed that the testing results of the indirect impedance method were completely consistent with that of national standard method. Meanwhile, the detection time was shorter than that of conventional method of 7 days. The sample could be determined whether is commercial sterility within 3 days.

采用高效液相色谱-串联质谱法测定了猪肉中9种β-受体激动剂的残留量。样品经β-葡萄糖醛苷酶/芳基硫酸酯酶酶解后加入高氯酸沉淀蛋白并离心,取上清液过PCX阳离子固相萃取小柱净化,用氨水-甲醇(5+95)混合液洗脱,氮气吹干后用乙腈定容至1 mL。以CAPCELL PAK CR色谱柱为分离柱,以10mmol·L-1乙酸铵溶液-乙腈(55+45)混合溶液(含体积分数为0.1%的甲酸)为流动相进行洗脱,采用电喷雾正离子源及选择反应监测模式进行测定,内标法进行定量。9种β-受体激动剂的质量浓度在4.00~100μg·L-1范围内与其峰面积呈线性关系,方法的检出限(3S/N)在0.09~0.50μg·L-1之间。对空白样品进行加标回收试验,回收率在83.2%~102%之间,测定值的相对标准偏差(n=6)在5.0%~12%之间。

This paper aims to understand the current situation of heavy metal pollution in paddy soil in West Guangxi, to provide a reference for heavy metal pollution control. The content of Cd, Pb and As of 50 soil samples of cultivation layer (0-20 cm), taken from main rice producing areas in West Guangxi, is determined. The environment quality of soil is assessed with the single factor index and the potential ecological risk of paddy soil is evaluated with the potential ecological risk index of Hakanson. The results show that the mean content of Cd, Pb, and As in paddy soil samples is 0.941, 26.46 and 10.16 mg/kg, respectively. The Cd content of 54.0% soil samples and the As content of 2.0% soil samples are higher than the standard II National Soil Environment Quality, and Cd in paddy soil has high potential ecological risk. Heavy metal pollution in paddy soil in West Guangxi is mainly Cd pollution.

This paper aims to understand the current situation of heavy metal pollution in paddy soil in West Guangxi, to provide a reference for heavy metal pollution control. The content of Cd, Pb and As of 50 soil samples of cultivation layer (0-20 cm), taken from main rice producing areas in West Guangxi, is determined. The environment quality of soil is assessed with the single factor index and the potential ecological risk of paddy soil is evaluated with the potential ecological risk index of Hakanson. The results show that the mean content of Cd, Pb, and As in paddy soil samples is 0.941, 26.46 and 10.16 mg/kg, respectively. The Cd content of 54.0% soil samples and the As content of 2.0% soil samples are higher than the standard II National Soil Environment Quality, and Cd in paddy soil has high potential ecological risk. Heavy metal pollution in paddy soil in West Guangxi is mainly Cd pollution.

The hydrolysis degree was presented as an evaluation criterion to optimize the enzymolysis technology of flavourzyme for Guangxi Ostrea rivularis. One-way experiment and orthogonal array were recommended in the optimization of the five factors including the ratio of material to water, temperature, pH value, protease volume, and time. The one-way experiments showed that the optimal combination was the ratio of material to water 1:2(g/mL), temperature 50 ℃, pH value 7.0, protease volume 2000 U/g, and hydrolysis time 4~6 h. The orthogonal arrays suggested that the optimal technology parameters were temperature 50 ℃, pH value 7.5, protease volume 3000 U/g, and hydrolysis time 6 h respectively. The experiment results provide the basic data for the application of the flavourzyme in the production of oyster oil.

【Objective】 The purpose of this investigation was to understand the status of heavy metal pollution in paddy soil in western Guangxi and provide references for heavy metal pollution control. 【Method】The contents of Cd, Pb, and As of 50 soil samples from cultivation layer(0-20 cm), which were taken from main rice producing areas in western Guangxi, were determined. The environment quality of soil was assessed with the single factor index and the potential ecological risk of paddy soil was evaluated with the potential ecological risk index of Hakanson. 【Result】The mean contents of Cd, Pb, and As in paddy soil samples were 0.941, 26.46 and 10.16 mg/kg, respectively. The Cd content of 54.0% soil samples and the As content of 2.0% soil samples were higher than the standard II of the national environment standard quality for soils. Cd in paddy soil showed high potential ecological risk. 【Conclusion】Paddy soil in western Guangxi was mainly polluted by Cd.

To optimize the four key factors including temperature, pH value, protease volume, and time for neutral proteinase hydrolyzing fresh oyster, the L16(44) orthogonal list was first chosen in the test, and then hydrolysis degree and percentage of delicious amino acid as array criteria. The optimal technology parameters for the hydrolysis degree were temperature 45 ℃, pH value 7.5, protease volume 3 900 U/g, and hydrolysis time 5 h, while using the percentage of delicious amino acid, instead of temperature 40 ℃, pH value 7.5, protease volume 3 900 U/g, and hydrolysis time 4 h. The results showed that the temperature was corroborated as the most important factor of enzymatic technology of neutral proteinase.

目的:了解广西市售龙眼(荔枝)干、桂圆肉、保鲜龙眼中SO2的残留情况,为市场监管部门加强食品安全监督提供参考.方法:2010年-2012年随机抽取广西市场上的保鲜龙眼、龙眼(荔枝)干、桂圆肉64个样品,按GB/T5009.34-2003《食品中亚硫酸盐的测定》第二法测定SO2残留量.结果:符合国家卫生标准的43份,合格率67％,其合格率从高到低依次为保鲜龙眼(100％)＞龙眼干(75％)＞荔枝干(69％)＞桂圆肉(50％).结论:广西市售龙眼(荔枝)干、桂圆肉中,超国家卫生标准的达33％,不同程度地存在SO2残留量超标的情况,桂圆肉中最高SO2残留量超国家卫生标准8.6倍.

Formaldehyde,benzene,total volatile organic compounds(TVOC),ammonia,radon in indoor air were determined in 30 residential buildings and 5 office buildings after decorating in Guangxi Nanning city.The results showed that TVOC exceed the national standard more than any other item,samples overstep percentage in residential buildings such as sample point was 67.2% and sample unit was 80.0%,in office building was 15.2%;TVOC overstep percentage in residential building dissimilarity function such as living room was 58.6%,in bedroom was 60.7%,in reading?room was 80.8%,in kitchen was 55.6%.The research indicated decorating related indoor environmental severe contamination,mostly resulted in indoor air quality declining.Finally some countermeasures of prevention and suggestions were promoted to solve the problem.

The fresh fruit samples were dissolved with a mixed solution of HNO3-H2O2(4+2) by microwave digestion,and the amount of sulfur in the samples solution was determined by ICP-AES.Wavelength of 182.0nm was selected as analytical spectral line.Detection limit(3Sd) of the method was 0.065mg·L-1,and the relative standard deviation(n=8) was 1.90%.The proposed method was used in determination of sulfur in 2 national standard samples(standard reference materials tea GBW 10016 and apple GBW 10019),and the obtained results were in conformity with standard values.The results of measurement were in good agreement with those obtained from the proposed method and barium sulfate gravimetric method.The samples recovery(n=8) was between 100% and 102%.

According to the Chinese Pharmacopoeia 2005 version,the indexes of Loureirin B Standard Material were analyzed.The results showed that the material meets the technical requirements of chemical standard materials of Chinese herbal medicines.On this basis,researches and developments of Loureirin B Standard Material were proceed,and the Quality Standard was established to control its quality.

文章对离子色谱法对味精中硫酸盐的测定方法进行研究,并与分光光度法进行方法对比。实验采用抑制型离子色谱仪为测定手段,以浓度为10mmol·L-1,流速为1.0mL·min-1的KOH为淋洗液,建立了离子色谱法在13.5min内测定味精中硫酸盐含量。得到结果与分光光度法对比无显著差异,加标回收率在92.5%～107%之间。

以肉鸡为试验动物,选用禁用药物洛克沙胂和需制定休药期的氟苯尼考粉剂以及不需制定停药期的盐酸林可霉素粉作为试验添加药物,做含量梯度饲喂试验,阶段监测养殖产品胴体兽药残留情况.结果表明:禁用药物洛克沙胂在动物体内残留严重;氟苯尼考应用阶段有残留,休药期后残留消失;盐酸林可霉素残留不明显.说明兽药添加剂直接混饲要使用低残留、高效、无毒的药荆.

The present work is an attempt to study the risk factors of veterinary drug residue and quality of aquaculture products.The differences in pollution-free product standards in China and European Union were compared and the quality detection methods for aquaculture products were also discussed.On the basis of data collected in our study,some suggestions have been put forward which includes: the constructions of information feedback system for aquaculture,HACCP Management System,traceability system for product identification and supervision mechanism,use of rapid detection system for enterprises self-control.The functional laboratories should be equipped with advanced equipment for monitoring and verification of the fishery products.The triple quality security control system of enterprise self-test,supervision of samples by government authorities and certification of the tested products should be ensured at different steps to ensure the quality safety of aquaculture products.

通过对广西北部湾近岸海域近江牡蛎及养殖海水样品中的铜、镉、无机砷、铅、铬和甲基汞等重金属含量分析测定,探索广西近江牡蛎养殖环境与产品的污染状况;采用单因子污染指数法对牡蛎的重金属污染状况进行了评价。

The chemical components in the aromatic water of essential oil from Melaleuca alternifolia were identified by GC-MS-DS and were compared with the essential oil.More than 40 peaks were separated,and 22 components were identified whose peak area were more than 90% in the total chromatography peaks area.The chemical components of the aromatic water and the essential oil from Melaleuca alternifolia were basically the same,they have the common main components.The productive rate of aromatic water could be enhanced by using twice-distillation procedure for recovering the light components.The aromatic water can also be developed into a natural medicine health care,sterile,skin care,washing,and other new products.