Development of ELISA for melamine detection in milk powder

A sensitive ELISA method was developed based on a monoclonal antibody to detect melamine in milk powder. Two haptens were prepared using the melamine structural analogue, 2-chloro-4, 6-diamino-1, 3, 5-triazine. The obtained antibody belonged to the IgG1κ family and had high affinity for melamine (affinity constant was 3.09×10⁹). The antibody could also recognise cyromazine (cross-reactivity was 131%) and had low cross-reactivity toward the haptens. The effects of pH, ionic strength and organic solvents on ELISA performance were evaluated. The lowest IC₅₀ value (6.0±0.55 ng/mL) and the limit of detection in milk powder, 50 ng/g, were achieved under optimised conditions. Milk powder spiked at two levels of melamine (100 ng/g and 500 ng/g) was analysed with this ELISA method. Good recovery was obtained (76.2±7.3% at the 100 ng/g spiked level and 91.4±5.0% at 500 ng/g).     

Incredible pharmaceutical residues in human milk in a cohort study from Şanlıurfa in Turkey

Maternal milk is essential for optimum growth and development of an infant. The aim was to examine the presence of pharmaceutical residuals in breastmilk. This cohort study enrolled 90 healthy mother-infant pairs at 5−14 days after delivery and a control examination was performed 4–8 weeks later. Milk samples were taken at both visits. RANDOX Infiniplex kit performed residual analysis. More than half of mothers (54.4 %) had anti-inflammatory drug residues in at least one milk sample: those were 52.2 % for tolfenamic acid and 2.2 % for meloxicam and 1.1 % for metamizole. The most frequent residue group included the beta-lactam antibiotic group, which was detected in 93.3 % of mothers’ milk. The second one was the quinolone group (81.1 %). One-third of mothers expressed nitroxynil and one-fifth polymyxin in at least one sample. Almost all mothers had some unexpected drug residues in their milk. Additional studies from other countries can display maternal environmental exposures.     

冻干驴乳粉中的矿物元素含量测定分析

按国标法对冻干驴乳粉中11种矿物元素含量进行测定,结果表明:驴乳粉含人体必需的常量和微量矿物元素,其中钙819 mg/100g、磷604 mg/100g、钾672 mg/100g、钠183 mg/100g、镁86 mg/100g、氯547 mg/100 g,钙磷比值1.36,钠钾比值0.27,同时还含有铁、锌、锰、铜、硒等。     

荷斯坦牛乳脂率、乳蛋白率变化规律及其相关性分析

为探讨原料乳中乳脂率、乳蛋白率的影响因素及其之间的相关关系,本文收集新疆地区呼图壁种牛场牧一场和牧三场、天山畜牧生物股份有限公司牛场、沙湾金牛场、西部牧业共5个牧场4 727头次荷斯坦奶牛的生产性能记录,采用SAS(8.1)软件分析不同牧场、年度、季节、胎次对乳脂率和乳蛋白率的影响,并运用SPSS16.0软件进行相关性分析。结果表明:牧场、年度、季节、胎次均对乳脂率和乳蛋白率有极显著影响(P0.01)。相关性分析结果表明,乳脂率与乳蛋白率呈极显著正相关,相关系数为0.11。通过分析牧场、年度、季节、胎次对乳脂率、乳蛋白率的影响及相关关系,加深影响乳成分因素的认识,提示在生产中要做好饲养管理工作,并根据季节变化、奶牛胎次的增加,结合奶牛营养需求,采取具体措施调控影响乳成分的因素,从而提高原料乳质量。     

Adipokines in Breast Milk: An Update

Epidemiological surveys indicate that nutrition in infancy is implicated in the long-term tendency to obesity and that a longer duration of breastfeeding is associated with a protective effect against metabolic disorders later in life. However, the precise cause of this association is not well understood. Recent studies on the compounds present in human breast milk have identified various adipokines, including leptin, adiponectin, resistin, obestatin, nesfatin, ghrelin and apelins. Some of these compounds are involved in the regulation of food intake and energy balance. The presence of these adipokines in breast milk suggests that they may be responsible for the regulation of growth in early infancy and that they could influence the energy balance and development of metabolic disorders in childhood and adulthood.     

A survey of Aflatoxin M1 in some commercial milk samples and infant formula milk samples in Goa,India

A survey of aflatoxin M1 (AFM1) contamination in packaged milk and infant formula milk samples in the Goan market, India, was conducted using high performance liquid chromatography, association of analytical communities approved commercial kit and a sensitive chemiluminescent sandwich enzyme-linked immunosorbent assay (ELISA). A total of 72 samples of infant formula milk food (18) and packaged milk samples (54) was analysed. One hundred per cent of the analysed samples exceeded the European Communities recommended limits (50 ng/L) and 75% of the samples exceeded Codex Alimentarius, Food Safety and Standards Authority of India (FSSAI) and US Food and Drug Administration recommended limits (500 ng/L). The range of contamination of AFM1 was found lower in infant milk formula (501–713 ng/L) than liquid milk (511–809 ng/L). The methods were also compared for their performance, and ELISA was found to be most suitable for analysis of low-level AFM1 contamination in milk.