Absorption, distribution and elimination of fumonisin B1 metabolites in weaned piglets

The absorption, distribution and elimination of fumonisin B₁ (and B₂) after oral administration of Fusarium verticillioides (MRC 826) fungal culture, mixed into the experimental feed for 10 days, was studied in weaned barrows. In order to determine the absorption of FB₁ from the feed marked by chromium oxide, a special T-cannula was implanted into the distal part of pigs' ileum. During the feeding of toxin-containing diet (45 mg FB₁ kg^-1) and until the tenth day after the end of treatment, the total quantity of urine and faeces was collected and their toxin content analysed. At the end of the trial, samples of lung, liver, kidney, brain, muscle, and fat were also collected and their fumonisin content analysed by LC-MS. The fumonisins appeared to decrease the reduced glutathione content in blood plasma and red blood cell haemolysate, possibly associated with in vivo lipid peroxidation. From a data set of 80 individual data and the concentration and rate of C_r and fumonisins (FB₁, partially hydrolysed FB₁ and aminopentol) in the chymus, it could be established that the accumulative absorption of fumonisin B₁ was 3.9% ± 0.7%. In the chymus, the FB₁ conversions into aminopentol and partially hydrolysed FB₁ were 1.0 and 3.9%, respectively. The degree of metabolism in faeces was variable, although the main product was the partially hydrolysed form, with very small amounts of the aminopentol moiety being recovered. In the investigated tissues the FB₁ conversion to aminopentol and partially hydrolysed FB₁ was 30 and 20%, respectively.     

Absorption,distribution and elimination of fumonisin B1 metabolites in weaned piglets

The absorption, distribution and elimination of fumonisin B₁ (and B₂) after oral administration of Fusarium verticillioides (MRC 826) fungal culture, mixed into the experimental feed for 10 days, was studied in weaned barrows. In order to determine the absorption of FB₁ from the feed marked by chromium oxide, a special T-cannula was implanted into the distal part of pigs’ ileum. During the feeding of toxin-containing diet (45 mg FB₁ kg^?1) and until the tenth day after the end of treatment, the total quantity of urine and faeces was collected and their toxin content analysed. At the end of the trial, samples of lung, liver, kidney, brain, muscle, and fat were also collected and their fumonisin content analysed by LC-MS. The fumonisins appeared to decrease the reduced glutathione content in blood plasma and red blood cell haemolysate, possibly associated with in vivo lipid peroxidation. From a data set of 80 individual data and the concentration and rate of C _r and fumonisins (FB₁, partially hydrolysed FB₁ and aminopentol) in the chymus, it could be established that the accumulative absorption of fumonisin B₁ was 3.9% ± 0.7%. In the chymus, the FB₁ conversions into aminopentol and partially hydrolysed FB₁ were 1.0 and 3.9%, respectively. The degree of metabolism in faeces was variable, although the main product was the partially hydrolysed form, with very small amounts of the aminopentol moiety being recovered. In the investigated tissues the FB₁ conversion to aminopentol and partially hydrolysed FB₁ was 30 and 20%, respectively.     

抗氧化剂维生素E及其代谢物的毒理损伤

从维生素E及其在抗氧化历程中产生的代谢物的分子结构与功能入手,综述了新近发现的维生素E及其代谢物的毒理损伤,包括与心肌梗塞、高血压及肝硬化等疾病的产生关系密切.因此,在使用抗氧化剂时,应注意:①重新建立一套安全评估方案;②从分子水平更详尽地了解抗氧化剂的动力学变化和分子转化,以此对其利弊作出正确评估;③从生物动力学与生物效果模型中找出最佳食用剂量.     

Enterolignans enterolactone and enterodiol formation from their precursors by the action of intestinal microflora and their relationship with non-starch polysaccharides in various berries and vegetables

The aim of this work was to investigate the production of enterolactone (ENL) and enterodiol (END) both enterolignans, from their precursors by the action of intestinal microflora and their relationship with non-starch polysaccharides (NSP) in common plant foods such as berries and vegetables. For the investigation of the bioconversion of plant lignans the technique of in vitro fermentation was used and the quantitative analysis of their metabolites ENL and END was performed by HPLC with coulometric electrode array detection. The enterolignan production from various berries ranged from 7.8 to 382.8 nmol/g as well as from vegetables - from 10.5 till 91.2 nmol/g. By comparing different kind of berries, the cloudberry, raspberry, and strawberry were the best enterolignan producers. Considering vegetables, potatoes produced the highest quantity of total enterolignans. Garlic, zucchini and broccoli were the other good producers of enterolignans in this product group. The quantitative relationship between NSP components and their associated lignan metabolites were determined. The results showed that there is a correlation between the particularities of fermented food matrices and the production of enterolignans. For berries, an intermediate correlation was found between the total NSP and ENL values. For vegetables, higher correlations between NSP and END were found.     

Simultaneous determination of aditoprim and its three major metabolites in pigs,broilers and carp tissues,and its application in tissue distribution and depletion studies

Aditoprim (ADP) is a recently developed dihydrofolate reductase inhibitor that has shown promise for therapeutic use in veterinary medicine because of its excellent pharmacokinetic properties. In this study, a sensitive and reliable multi-residue chromatography-ultraviolet (HPLC-UV) method for the quantitative analysis of ADP and its three major metabolites was developed, and the tissue distribution and depletion profiles of ADP and its major metabolites in pigs, broilers and carp were investigated. Edible and additional tissues (heart, lung, stomach, intestine and swim bladder) were collected for analysis at six different withdrawal periods after ADP administration for 7 days. ADP, N-monomethyl-ADP and N-didesmethyl-ADP were detected in almost all tissues in the three species. The liver, kidney and lung showed higher residue concentrations, and the liver showed a longer residue half-life (t_1/2) than other tissues. In the liver, ADP was the most abundant component with the longest persistence. The results suggest that the liver was the residual target tissue and ADP was the marker residue, and the conclusive withdrawal time (WDT) of 20 days in pigs, 16 days in broilers and 25 days in carp was estimated using the assessment methodologies approved by the Joint FAO/WHO Expert Committee on Food Additives (JECFA).     

气相色谱法快速测定蛋中氟虫腈及其代谢物

目的建立气相色谱法同时快速测定蛋中氟虫腈及其代谢物残留量的分析方法。方法鸡蛋中的氟虫腈及其代谢物氟甲腈、氟虫腈硫醚、氟虫腈砜残留经乙腈提取,盐析,固相萃取小柱净化,采用气相色谱电子捕获检测器进行分离和测定,外标法定量。结果氟虫腈及其代谢物氟甲腈、氟虫腈硫醚、氟虫腈砜的检出限为0.2μg/kg,在0.2~200μg/kg范围内,线性相关系数大于0.9995。在所添加3个质量浓度水平下,方法的回收率在75.1%~102.0%,相对标准偏差为4.3%~6.4%。结论该方法简便、准确、重现性好,适合对蛋中氟虫腈及其代谢物进行有效监测。     

螺虫乙酯及其代谢物在番茄中的储藏稳定性

目的建立超高效液相色谱-串联质谱法测定番茄样品中螺虫乙酯及其代谢产物残留的分析方法,考察螺虫乙酯及其代谢产物在番茄中的储藏稳定性。方法低温储藏0～274 d的番茄样品经乙腈提取,采用NaCl和无水MgSO4除水,离心过膜后的上清液经超高效液相色谱-串联质谱测定,基质匹配标准溶液外标法定量。结果螺虫乙酯及其4种代谢产物在0.001～0.5mg/L范围内线性关系良好,在0.02、0.1、1和5mg/kg添加水平的平均回收率为75.1%～104.5%,相对标准偏差小于11.93%(n=5)。番茄样品在–18℃储藏条件下螺虫乙酯、螺虫乙酯烯醇、螺虫乙酯羟基、螺虫乙酯醇酮的平均降解率均小于30%,螺虫乙酯烯醇糖苷在储藏274 d时降解率大于30%(平均降解率53.3%)。结论–18℃条件下螺虫乙酯、螺虫乙酯烯醇、螺虫乙酯羟基、螺虫乙酯醇酮在番茄样品中的储藏稳定期至少为274 d,螺虫乙酯烯醇糖苷在番茄样品中储藏稳定期至少为182 d。     

恩诺沙星及其代谢物在俄罗斯鲟多组织中的 代谢及消除研究

目的研究恩诺沙星及其代谢产物环丙沙星在俄罗斯鲟中的代谢及消除规律,制定恩诺沙星在俄罗斯鲟体内的休药期。方法在水温12～15℃条件下,以60 mg/(kg?bw)剂量对体重为(750±50) g的健康俄罗斯鲟灌服恩诺沙星,灌服后的0～3360 h内不间断采样,使用高效液相色谱-串联质谱仪测定各组织内恩诺沙星及其代谢产物含量。结果灌药后,恩诺沙星在俄罗斯鲟鳃、血浆、肌肉、肝脏、肾脏、皮肤中达峰时间Tmax分别为0.25、9、12、12、18、24 h;肾脏、肝脏、皮肤、肌肉、鳃、血浆达峰浓度Cmax分别为31.863、23.435、21.434、18.640、10.342、2.599 mg/kg;消除半衰期以皮肤最大t1/2为394.431 h、血浆最小为129.6 h。鳃中药物浓度有2个峰值,第1次达峰时,血浆中药物浓度远低于鳃,推测与受试鱼进食习惯或组织结构有关。代谢产物环丙沙星代谢及消除趋势与恩诺沙星大致相同,血浆最早达峰, Tmax为12 h,达峰浓度以肝脏和肾脏较高,Cmax分别为6.876mg/kg和5.648mg/kg。结论从水产品质量安全角度应用本研究结果:以皮肤和肌肉作为可食性组织,恩诺沙星和环丙沙星残留总量不超过0.1 mg/kg至少需要100 d。     

草莓中氟啶虫胺腈及其代谢物降解规律及风险评估

目的 探究草莓生长过程中氟啶虫胺腈及其代谢物的残留降解变化规律以及膳食暴露风险。方法 利用超高效液相色谱-串联质谱法建立了草莓中氟啶虫胺腈及其代谢物的高灵敏度快速测定方法;通过田间试验,明确氟啶虫胺腈在草莓中的残留消解规律,并进行膳食风险评估。结果 在正离子多反应监测模式下,氟啶虫胺腈及其代谢物基质和溶液匹配标准曲线在0.1～100.0 ng/mL的浓度范围内线性关系良好,最低检出限为0.01μg/kg,最低定量限为0.02μg/kg,不同添加浓度下回收率范围在88.16%～104.14%,相对标准偏差小于等于9.18%,符合痕量检测的要求;田间试验结果表明氟啶虫胺腈在草莓中经过代谢会产生X11719474和X11721061 2种代谢产物,且消解规律符合一级动力学方程,半衰期为14.75 d;膳食风险评估结果表明,氟啶虫胺腈在草莓中膳食暴露风险较低。结论 以10 g/亩剂量在温室草莓上使用50%氟啶虫胺腈水分散粒剂,氟啶虫胺腈及其代谢物X11719474和X11721061无显著膳食暴露风险。     

食品中氟虫腈及其代谢物残留与检测研究进展

氟虫腈是一类广谱杀虫剂,通过与害虫等无脊椎动物神经中枢细胞膜上的γ-氨基丁酸受体结合,造成其神经功能受损,从而引起死亡,对主要农作物的害虫都有良好的防治效果,被广泛应用于农业、兽医等领域。但因其不仅对害虫有危害,对某些哺乳动物也存在毒性,故我国于2009年禁止氟虫腈作为农药使用。氟虫腈通过对土壤、水体等环境造成严重污染,从而对动植物体造成伤害,最终随着动植物食品进入身体威胁人类健康。本文主要列举了近5年国内外食品中氟虫腈及其代谢物污染现状,概述了测定食品中氟虫腈及其代谢物的前处理方法及检测方法的最新进展,对食品中氟虫腈及其代谢物的后续研究提出建议,为未来食品中农药和药物残留的控制提供参考。     

嗜盐单胞菌的分离及其胞外黏性代谢物的分析

从盐生杜氏藻培养废弃液中分离一株产胞外黏性代谢物的嗜盐菌YZ1,通过形态学观察及分子生物学技术对其进行鉴定,并对其生长特性进行研究。同时,采用傅里叶变换红外光谱（FT-IR）及气相色谱-质谱（GC-MS）对其胞外黏性代谢产物的组成进行分析。结果表明,菌株YZ1被鉴定为Halomonas subterranea。本研究培养条件下,其对数生长期为12～28 h,最适生长NaCl含量范围为30～150 g/L,最适生长初始pH值范围为7.0～8.0,最适生长温度范围为30～40 ℃。Halomonas subterranea YZ1发酵30 d时,胞外黏性代谢物产量为20 g/L,主要成分为糖蛋白或脂蛋白类。     

Behaviour of spirotetramat residues and its four metabolites in citrus marmalade during home processing

The effect of home processing on the residues of spirotetramat and its four metabolites (B-enol, B-glu, B-mono and B-keto) in citrus marmalade is comprehensively investigated in this paper by ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). A five-fold recommended dose of spirotetramat was applied to citrus fruit under field conditions and the processing included five steps: washing, peeling, pre-treatment for peel, mixing and boiling. The results showed that spirotetramat was the predominant component detected in unprocessed citrus, accounting for 64%. All the detected residues were primarily deposited on citrus peel, except for B-enol which was also present in the citrus pulp. Washing reduced spirotetramat, B-enol, B-glu and B-keto by 83%, 56%, 41% and 16%, respectively, and pre-treatment of the peel removed between 42% and 68% of the residues. Four compounds were all below the limit of detection after the mixing step. In the final product, only B-keto was detected at the concentration of 0.010 mg kg^–1. After the whole process, the processing factors for spirotetramat, B-enol, B-glu and B-keto were < 0.041, < 0.125, < 0.294 and 0.313, respectively, which indicated that home processing can significantly reduce residues of spirotetramat and its metabolites in citrus marmalade.     

QuEChERS-液相色谱-串联质谱联用法测定草莓中毒死蜱及其代谢物

目的建立草莓中毒死蜱及其代谢物残留检测的QuEChERS-液相色谱-串联质谱联用方法。方法草莓样品用乙腈提取后所得液经过QuEChERS法净化去除杂质。采用5 mmol乙酸铵水-甲醇流动相体系进行洗脱,C_(18)色谱柱进行色谱分离,电喷雾正负离子模式电离,多反应监测(multiple-reaction monitoring,MRM),外标法定量。结果 3,5,6-三氯-2-羟基吡啶(3,5,6-trichloro-2-pyridi-nol,TCP)、毒死蜱、毒死蜱氧和甲基毒死蜱在1.0~200μg/L浓度范围内线性良好,相关系数均为0.999,检出限为0.008~0.279μg/kg,定量限为0.026~0.926μg/kg。在0.010、0.050和0.100 mg/kg 3个浓度水平的平均回收率为71.33%~99.43%,相对标准偏差在1.51%~5.96%之间。结论本方法操作简便,耗时较短,准确度与精密度较好,适应性广,容易形成标准化操作,可用于草莓样品中毒死蜱及其代谢物残留的分析。     

动物源性食品中头孢菌素及代谢物残留分析方法研究进展

在畜禽养殖过程中大量使用广谱、高效的头孢菌素类抗生素以防治疾病,由此引发的食品安全风险得到科研工作者的广泛关注。然而,进行动物源性食品中头孢菌素残留的市场风险筛查时发现,基本无法检出残留量。头孢菌素可能以代谢物的形式存在于食品中,而部分代谢物具有杀菌活性、致敏性及细菌耐药性,一旦为人体摄入,甚至可能产生肝肾毒性,由此引发食品安全风险。动物源性食品基质复杂,且其中残留的头孢菌素类抗生素及代谢物含量甚微,因此,开展新型、快速的复杂基质样品前处理,以及灵敏、准确、高通量的头孢菌素类抗生素及代谢物的仪器分析方法的研究非常必要。本文对国内外动物源性食品中头孢菌素类抗生素及代谢物残留分析检测现状进行了阐述,详细介绍了样品前处理和分析检测方法的研究进展,为深入持续相关研究、科学有效保障食品安全提供重要的理论基础。     

食荚豌豆和豌豆中螺虫乙酯及其代谢物残留和膳食摄入风险评估

目的 研究食荚豌豆和豌豆中螺虫乙酯主要代谢物的转化情况,施药措施与残留量的相关性,残留量膳食摄入评估.方法 样品中螺虫乙酯及其代谢物加乙腈提取,N-丙基乙二胺和石墨化碳黑净化,离心,上清液过滤膜后高效液相色谱-三重四极杆串联质谱法检测,对施用过螺虫乙酯的食荚豌豆和豌豆样品进行检测分析及膳食摄入评估.结果 食荚豌豆和豌豆...     

Absorption, distribution and elimination of fumonisin B(1) metabolites in weaned piglets

The absorption, distribution and elimination of fumonisin B(1) (and B(2)) after oral administration of Fusarium verticillioides (MRC 826) fungal culture, mixed into the experimental feed for 10 days, was studied in weaned barrows. In order to determine the absorption of FB(1) from the feed marked by chromium oxide, a special T-cannula was implanted into the distal part of pigs' ileum. During the feeding of toxin-containing diet (45 mg FB(1) kg(-1)) and until the tenth day after the end of treatment, the total quantity of urine and faeces was collected and their toxin content analysed. At the end of the trial, samples of lung, liver, kidney, brain, muscle, and fat were also collected and their fumonisin content analysed by LC-MS. The fumonisins appeared to decrease the reduced glutathione content in blood plasma and red blood cell haemolysate, possibly associated with in vivo lipid peroxidation. From a data set of 80 individual data and the concentration and rate of C(r) and fumonisins (FB(1), partially hydrolysed FB(1) and aminopentol) in the chymus, it could be established that the accumulative absorption of fumonisin B(1) was 3.9% +/- 0.7%. In the chymus, the FB(1) conversions into aminopentol and partially hydrolysed FB(1) were 1.0 and 3.9%, respectively. The degree of metabolism in faeces was variable, although the main product was the partially hydrolysed form, with very small amounts of the aminopentol moiety being recovered. In the investigated tissues the FB(1) conversion to aminopentol and partially hydrolysed FB(1) was 30 and 20%, respectively.