HPLC法测定乳制品中苯甲酸、山梨酸、糖精钠方法研究

目的　建立乳制品中食品添加剂苯甲酸、山梨酸、糖精钠的高效液相色谱测定法。方法　应用沉淀剂去除乳制品中蛋白质和脂肪后用高效液相色谱法测定乳制品中的苯甲酸、山梨酸、糖精钠。结果　苯甲酸、山梨酸、糖精钠在 0～ 30mg/L范围内呈良好线性关系 (r =0 .9999) ;检出限为苯甲酸 0 .2mg/L、山梨酸 0 .2 7mg/L、糖精钠 0 .17mg/L ;方法的回收率为苯甲酸 91.1%～ 10 1.2 %、山梨酸 93.2 %～ 97.8%、糖精钠 92 .6 %～ 10 1.3% ;相对标准偏差苯甲酸 2 .7%、山梨酸 4 .4 %、糖精钠 2 .9%。结论　本方法简单、快速、准确易操作 ,适用于乳制品中苯甲酸、山梨酸、糖精钠的测定 ,结果满意。     

高效液相色谱法同时测定食品中的苯甲酸、山梨酸、脱氢乙酸及糖精钠

目的:采用0.3%盐酸乙醇提取,低温下沉淀蛋白质,水定容离心过滤的前处理方法,高效液相色谱法同时测定苯甲酸、山梨酸、脱氢乙酸及糖精钠。方法:色谱柱DIONEX Acclaim120 C18(4.6×250 mm,5μm),甲醇-0.02 mol/L磷酸氢二钾溶液pH 7.0(10∶90)为流动相,流速:1.0 ml/min,检测波长:230 nm(苯甲酸、山梨酸、糖精钠)和293 nm(脱氢乙酸)。结果:苯甲酸、山梨酸、脱氢乙酸及糖精钠在0.1μg/ml～20μg/ml浓度范围内线性关系良好(r>0.9999),检出限小于0.4 mg/kg,其加标回收率在92.6%～105.4%之间,重复测定的RSD≤2.0%。结论:该方法操作简单,灵敏度高,准确性好,可应用于大批量样品的快速检测。     

食品中常用防腐剂和甜味剂的高效液相色谱同时测定法

目的建立食品中苯甲酸、山梨酸、糖精钠、乙酰磺胺酸钾、阿斯巴甜5种食品添加剂的高效液相色谱同时测定方法。方法采用ODS色谱柱,甲醇+0.02mol/L,乙酸铵(pH=6)(10+90)为流动相,流速1.0ml/min,二极管阵列检测器,阿斯巴甜检测波长214nm,其他均为228nm。根据保留时间、光谱图定性,峰高或峰面积定量。结果该方法5种添加剂在20～500μg/ml浓度范围内线性良好,相关系数达到0.99992～0.99999。相对标准偏差为1.6%～3.5%,回收率为92.1%～105.7%。苯甲酸、山梨酸、糖精钠、乙酰磺胺酸钾、阿斯巴甜的最低检出限依次为2.3、2.0、4.1、2.1、10.5mg/kg。结论该方法简便快速,准确可靠,可用于各类食品中苯甲酸、山梨酸、糖精钠、乙酰磺胺酸钾、阿斯巴甜含量的同时测定。     

UPLC法同时测定食品中5种添加剂

[目的]建立超高效液相色谱UPLC快速分离和测定食品中安赛蜜、苯甲酸、山梨酸、糖精钠、脱氢乙酸等的方法.[方法]样品经沉淀蛋白、超声提取、离心、过滤等预处理,采用乙酸铵(0.02 mol/ml)-甲醇(体积比93:7),检测波长230 nm,二极管阵列检测器,外标法定量.[结论]该方法精密度高、准确性好,样品处理简单,测得安赛蜜、苯甲酸、山梨酸、糖精钠、脱氢乙酸在0.2～20 mg/kg范围内线性良好,回收率在90.1～105.3之间,检出浓度为安赛蜜、苯甲酸、山梨酸0.02 mg/kg,糖精钠、脱氢乙酸0.04 mg/kg.[结论]该方法具有简便、快速、准确的优点,可用于食品中安赛蜜、脱氢乙酸、苯甲酸、山梨酸、糖精钠的检测.     

橙汁中糖精钠、苯甲酸、山梨酸测定方法的探讨

2003年11月参加亚太地区国家实验室能力验证盲样考核,要求测定橙汁中糖精钠、苯甲酸、山梨酸三种食品添加剂。本文就其测定方法做了一些研究,重点对HPLC法的有关问题进行了总结,改进了方法,获得满意结果。1 实验部分1.1 仪器与试剂1.1.1 PE Integral-4000型高效液相色谱仪。1.1.2 二极管阵列式检测器。1.1.3 模拟盲样:80%橙汁 20%水(加入适量标准)。1.1.4 0.2mol/L乙酸铵水溶液(临用新配)、10%醋酸铅水溶液、10%硫酸钠水溶液、0.02mol/L氢氧化钠水溶液、甲醇(色谱纯)。1.1.5 糖精钠标准溶液(1.00mg/ml):国家标准物质研究中心     

水果罐头中苯甲酸(钠)、山梨酸(钾)、脱氢乙酸(钠)和糖精钠的反相高效液相色谱法测定

目的:建立反相高效液相色谱同时检测水果罐头食品中苯甲酸(钠)、山梨酸(钾)、脱氢乙酸(钠)和甜味剂糖精钠的分析方法。方法:样品液调节pH7.0定容至适当体积后,超声提取10 min,最后经0.45μm针式滤头过滤,进10μl滤液上机检测。选用YWG-C18 4.6 mm×25 mm,10μm分析柱,甲醇:0.02 mol/L醋酸铵溶液(V∶V)=10∶90流动相,流速1.2 ml/min,波长230 nm下进行检测,以保留时间定性,峰面积定量。结果:一次进样分析仅需12 min。在1.0μg/ml～200.0μg/ml内线性正相关,R都在0.9995以上。苯甲酸、山梨酸、脱氢乙酸和糖精钠最低检测浓度依次分别为1.7 mg/kg、1.2 mg/kg、3.0 mg/kg、2.8 mg/kg,回收率为96%～110%,相对标准偏差(n=7)小于3%。结论:该法准确、快速、简单能够同时分析测定水果罐头中这四种食品添加剂。     

饮料中6种添加剂超高效液相色谱测定

目的:建立饮料中6种食品添加剂的超高效液相色谱同时测定方法。方法:样品经乙腈去除蛋白后用水稀释,采用C18色谱柱,以乙酸铵缓冲液(0.02 mol/L)/甲醇为流动相,采用梯度洗脱分离,在230 nm波长下进行检测。结果:6种食品添加剂的加标回收率在90%~108%之间,相对标准偏差在1.0%~3.8%之间。阿斯巴甜在15μg/m l~100μg/m l范围具有良好的线性,安赛蜜、苯甲酸、山梨酸、糖精钠和咖啡因在1μg/m l~10μg/m l范围具有良好的线性,回归系数均大于0.999,最低定量限分别为,安赛蜜0.05 mg/L,苯甲酸0.05 mg/L,山梨酸0.02 mg/L,糖精钠0.1 mg/L,咖啡因0.1 mg/L,阿斯巴甜1.0 mg/L。结论:本方法简便、灵敏、重现性好,能满足饮料中6中添加剂的测定要求。     

超高效液相色谱法测定冷面汤中山梨酸、苯甲酸、安赛蜜、糖精钠含量

目的建立超高效液相色谱分析冷面汤中山梨酸、苯甲酸、安赛蜜、糖精钠含量的方法。方法取2 g左右样品,加少量水稀释,用氨水(1+1)溶液调节酸度至pH 6.5～7.5,用水定容至25 ml。所得溶液过0.22μm滤膜,进行超高效液相色谱分离;以C_(18)反相色谱柱为固定相,以乙酸铵溶液+甲醇为流动相进行梯度分析。结果山梨酸、苯甲酸、安赛蜜、糖精钠的质量浓度在0.1～50 mg/L内与峰面积呈线性关系,检出限(3S//N)分别为0.5、0.5、0.5、1.0 mg/Kg。按标准加入法在3个浓度水平上进行回收试验,回收率为86%～96%,测定值的相对标准偏差(n=6)均10%。结论该方法操作简单、干扰小,准确度可靠,能够分析冷面汤中山梨酸、苯甲酸、安赛蜜和糖精钠含量。     

液相色谱-质谱联用检测食品中苯甲酸、山梨酸、糖精钠

目的：建立高效液相-质谱联用仪检测各类食品中苯甲酸、山梨酸、糖精钠的方法。方法：采用HPl00高效液相色谱一质谱联用系统；C18柱；流动相：甲醇：0．02mol／L乙酸铵=5：95；流速：1ml／min；检测波长：230nm；质谱扫描（m／z）：50～500amu；苯甲酸、山梨酸、糖精钠选择性荷质比（m／z）为：121；111；182。结果：在质量范围内线性良好，r=0．9999，苯甲酸、山梨酸、糖精钠回收率92％～105％。结论：方法具有高度的灵敏性和专属性，能对食品中苯甲酸、山梨酸、糖精钠进行准确定性和定量检测，是可行有效的检测方法。     

大理市售梅产品中山梨酸、苯甲酸和糖精钠的 分析与评价

摘要:目的　了解大理市售梅产品中山梨酸、苯甲酸和糖精钠的使用情况。方法　采用高效液相色谱法,对随机选取的大理市售梅产品5大类、22种不同口味类型的66个梅子样本,分别检测山梨酸、苯甲酸和糖精钠含量并进行结果分析。结果　苯甲酸、山梨酸和糖精钠检出最高检出含量值分别为298.1mg/kg、254.0 mg/kg和774.7 mg/kg,均未超出国家卫生标准最大使用量。结论　本次采集的大理市售梅子产品山梨酸、苯甲酸和糖精钠的最高检出含量未超出国家卫生标准最大使用量,但不同品牌和种类梅产品中均检出了所测食品添加剂,应该加强梅产品的抽查和监督力度,保障食品安全。     

Folic Acid

Folic acid exists in many different chemical forms in living tissues, and it takes part in a wide variety of biochemical and physiological processes, many of which are, at present, incompletely understood. Recent observations suggest it may fulfil important functions in the brain, as well as in haemopoietic and gastrointestinal tissues, with pathological consequences for subjects who are folate deficient, either through dietary insufficiency, or through drug-induced or genetically determined increases in requirements. The currently available information about the folate content of foods is unsatisfactory, and the levels may, for technical reasons, have been considerably underestimated. Likewise, the available information about minimum human requirements is incomplete, and it is therefore impossible to accept current recommendations of advisable intakes without reservation. The potential importance of folate status, particularly with regard to early fetal development, renders this subject extremely important, and ripe for reappraisal and reinvestigation.     

Anti-Diabetic Effects of Madecassic Acid and Rotundic Acid

Anti-diabetic effects of madecassic acid (MEA) and rotundic acid (RA) were examined. MEA or RA at 0.05% or 0.1% was supplied to diabetic mice for six weeks. The intake of MEA, not RA, dose-dependently lowered plasma glucose level and increased plasma insulin level. MEA, not RA, intake dose-dependently reduced plasminogen activator inhibitor-1 activity and fibrinogen level; as well as restored antithrombin-III and protein C activities in plasma of diabetic mice. MEA or RA intake decreased triglyceride and cholesterol levels in plasma and liver. Histological data agreed that MEA or RA intake lowered hepatic lipid droplets, determined by ORO stain. MEA intake dose-dependently declined reactive oxygen species (ROS) and oxidized glutathione levels, increased glutathione content and maintained the activity of glutathione reductase and catalase in the heart and kidneys of diabetic mice. MEA intake dose-dependently reduced interleukin (IL)-1β, IL-6, tumor necrosis factor-α and monocyte chemoattractant protein-1 levels in the heart and kidneys of diabetic mice. RA intake at 0.1% declined cardiac and renal levels of these inflammatory factors. These data indicated that MEA improved glycemic control and hemostatic imbalance, lowered lipid accumulation, and attenuated oxidative and inflammatory stress in diabetic mice. Thus, madecassic acid could be considered as an anti-diabetic agent.     

The Omega-3 Fatty Acid Docosahexaenoic Acid Attenuates Organic Dust-Induced Airway Inflammation

Workers exposed to organic dusts from concentrated animal feeding operations (CAFOs) are at risk for developing airway inflammatory diseases. Available preventative and therapeutic measures for alleviating dust-induced lung disease are inadequate. Because omega-3 fatty acids can mitigate inflammatory processes, we aimed to determine whether nutritional supplementation with the omega-3 fatty acid docosahexaenoic acid (DHA) could reduce the airway inflammatory consequences of exposures to organic dust. Aqueous extracts of organic dusts from swine CAFOs (ODE) were utilized. In DHA-pretreated human bronchial epithelial cells, lung fibroblasts, monocyte cell cultures, and precision-cut murine lung slices, we found that DHA pretreatment dose-dependently decreased ODE-induced inflammatory cytokine production. To determine the in vivo significance of DHA, C57BL/6 mice were orally administered DHA for seven days prior to treatment with intranasal ODE or saline inhalations. Animals treated with 2 mg DHA demonstrated significant reductions in ODE-induced bronchial alveolar lavage neutrophil influx and pro-inflammatory cytokine/chemokine production compared to mice exposed to ODE alone. Collectively, these data demonstrate that DHA affects several lung cells to reduce the airway inflammatory response to organic dust exposures. Dietary supplementation with DHA may be an effective therapeutic strategy to reduce the airway inflammatory consequences in individuals exposed to agriculture dust environments.