Occurrence and formation of biologically active amines in foods

Attention is given to the toxicology of biogenic amines and their occurrence and formation in foods, with special emphasis on fermented foods. The role of the associated flora, the starter cultures used and their interaction is discussed.     

Occurrence of beta-phenylethylamine and its derivatives in cocoa and cocoa products]

2-Phenylethylamine was extracted from cocoa nibs and chocolates and analysed by coupled gas chromatography-mass spectroscopy. The amine concentration increases in fermentation of cocoa and decreased during roasting and alkalization. Its concentration in chocolates is dependent on non-fat cocoa contents. Previously unreported aldimines were found in cocoa powders, which arise from the condensation of phenylethylamine and aldehydes. The main component of these products is N-phenylmethyl-N-phenylmethylene amine (CAS 3240-95-7).     

Database of biologically active peptide sequences

Proteins are sources of many peptides with diverse biological activity. Such peptides are considered as valuable components of foods with desired and designed biological activity. Two strategies are currently recommended for research in the area of biological activity of food protein fragments. The first strategy covers investigations on products of enzymic hydrolysis of proteins. The second one is synthesis of peptides identical with protein fragments and investigations using these peptides. It is possible to predict biological activity of protein fragments using sequence alignments between proteins and biologically active peptides from database. Our database contains currently 527 sequences of bioactive peptides with antihypertensive, opioid, immunomodulating and other activities. The sequence alignments can give information about localization of biologically active fragments in protein chain, but not about possibilities of enzymic release of such fragments. The information is thus equivalent with this obtained using synthetic peptides identical with protein fragments. Possibilities offered by the database are discussed using wheat α/β-gliadin, bovine β-lactoglobulin and bovine β-casein (including influence of genetic polymorphism and genetic engineering on amino acid sequences) as examples.     

Microecological system and its importance in evaluation of the effectiveness of biologically active supplements and probiotic products

A possibility to estimate a quality of bioactive supplements and probiotical foods by their influence on microecological system of a gastrointestinal tract are exhibited as a result of multiyear research. The consist and biological activity of micropopulations, including the normalization of level of protective intestinal microflora, the increasing their antibiosis activity, the elimination of potentially pathogenic microorganisms, the excretion of volatile phenols and indican with urine, the content of volatile fatty acids, enzymes, secretory immunoglobulins in feces, destruction in vitro cholic acid and cholesterol etc., are tested as indicators. The reasoned supposal is advanced that the wide spread of disbacteriosis is connected not only with changing of defence mechanisms (reactions) of macroorganism, but also with accumulation of pathogenic features in microorganisms by action of environmental factors.     

Occurrence of lactic acid bacteria and biogenic amines in biologically aged wines

Biologically aged sherry-type wines are elaborated by the so-called 'criadera and solera' system, which essentially involves development of the yeast on the wine surface forming a film velum for several years. Lactic acid bacteria can also develop and contribute to sherry-type wine quality, although their presence and role in this enological process have received very little attention. In this study, lactic acid bacteria microbiota and the presence of biogenic amines were investigated throughout the manufacture and biological aging of 36 samples of sherry wines. Malolactic fermentation was found to mainly take place during the first stage of biological ageing. The incidence and populations of lactic acid bacteria in sherry wines were low. The diversity of bacterial species isolated from the wines was greater than previously reported and included species of Lactobacillus, with prevailing Lactobacillus hilgardii, Lactobacillus plantarum and Lactobacillus zeae and Leuconostoc mesenteroides. The biogenic amine-producing capacity of the isolates was also determined. Five strains were putrescine producers, while another strain was shown to produce tyramine and phenylethylamine, simultaneously. L. zeae was one of the predominant species in wines during the biological aging and seemed to be one of the main putrescine producers. The biogenic amine composition of the wines investigated was similar to that reported for other types of wines. Putrescine was the major amine, followed by cadaverine, histamine and tyramine. The amine contents detected were lower than those usually reported in red wines.     

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。     

Lack of biologically active estrogens in commercial cow milk

Recently, many studies have investigated potential estrogenic compounds in the human diet. Several of these investigations have studied cow milk, a mainstay of the diets of both young and old. In vitro studies have determined that estrogens can be found in milk, and that the concentration of estrogen may be correlated to the fat content in the milk. Regardless, the majority of these studies have concluded that the levels of estrogens in milk are too low to have a physiological effect. However, a recent study found that commercial 1% cow milk was uterotrophic in rats, suggesting that it contained biologically significant levels of estrogen. Using the rat model, we tested milk samples from commercial sources and with varying fat content for estrogenic activity. Ovariectomized female rats were given milk ad libitum for a period of 2 wk. After 12 d of treatment, rats were tested sequentially in an open field and an elevated plus maze to determine any effect of milk on anxiety levels. Upon completion of the behavior testing, uterine weights were examined. Regardless of milk type, no difference was observed in daily volume of milk consumed. Contrary to previous publications, no differences existed in either the behavior or the uterine weights between animals that consumed any milk type and the negative controls. These results demonstrated that none of the commercial milk types that we tested contained biologically significant estrogenic activity.     

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。     

生物活性多糖及其在食品中的应用前景

生物活性多糖主要可划分为真菌多糖、植物多糖、动物多糖三大类,它们不仅可以赋予食品保健功能的特性,而且可以显著改善食品的品质,因而在食品中具有广阔的应用前景。     

Sensitive bioassay for detection of biologically active ricin in food

The potential use of ricin as an agent of biological warfare highlights the need to develop fast and effective methods to detect biologically active ricin. The current "gold standard" for ricin detection is an in vivo mouse bioassay; however, this method is not practical to test on a large number of samples and raises ethical concerns with regard to the use of experimental animals. In this work, we generated adenoviral vectors that express the green fluorescent protein gene and used the relative fluorescence units intensity inhibition by transduced cells for quantitative measurement of biologically active ricin. The detection limit of the assay was 200 pg/ml, which is over 500,000 times greater than the adult human lethal oral dose. The inhibition of fluorescence intensity between ricin treatment and control was higher in 72-h posttransduction Vero cells than 24-h human embryonic kidney cells. Therefore, to detect biologically active ricin in food matrices that might influence the assay, we used 72-h posttransduction Vero cells. This simple assay could be used for large-scale screening to detect biologically active ricin in food without added substrates or use of cell fixation methods.     

The quantitative analysis of biologically active compounds in Lithuanian honey

Different sorts of Lithuanian honey were analysed by quantitative determination of eight free phenolic acids and phenylpropanoid vanillin using high performance liquid chromatography (HPLC). Aqueous ethanol 60% was used as a solvent for preparation of honey samples. Amounts of phenolic acids honey solutions were in the range from 7.176 to 125.624 mg/ml. Free phenolic acids and vanillin had been detected in all samples of honey, but their composition and amount depended on its botanic origin. p-Coumaric and ferulic acids proved to be the main components in the acacia and buckwheat honey. Raspberry and polyfloral forest honey contained the highest amounts of chlorogenic acid. Gallic acid is a principal phenolic acid in eucalyptus honey. The highest amount of vanillin was identified in buckwheat honey. The results of the analysis revealed that free phenolic acids and vanillin were detected in all honey samples analysed, and their range and amounts varied.     

酶解豆清液制备生物活性多肽工艺优化及抗氧化能力研究

目的 探究木瓜蛋白酶酶解豆清液制备生物活性多肽的最佳工艺条件,评价该生物活性多肽的抗氧化能力。方法 以三氯乙酸-双缩脲法测得的多肽产率为参考指标,在单因素实验结果基础上,通过响应面实验确定酶解豆清液的最优酶解条件,并通过测定2,2-联氮-二(3-乙基-苯并噻唑-6-磺酸)二铵盐（2,2''-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid,ABTS+·）、1,1-二苯基-2-三硝基苯肼（1,1-diphenyl-2-picrylhydrazyl,DPPH）自由基清除率,分析豆清多肽的抗氧化活性。结果 最佳酶解条件：木瓜蛋白酶添加量2.0%、初始pH 5.0、酶解温度53 ℃、酶解时间7 h,在该条件下豆清液的多肽产率为115.50%与预测值范围内。抗氧化实验测得Vc（维生素C, vitamin C）与样品对ABTS自由基清除能力EC50值分别为0.003、1.871 mg/mL,对DPPH自由基清除能力EC50值分别为0.006、6.459 mg/mL,说明样品具有一定的抗氧化能力。结论 木瓜蛋白酶酶解豆清液制备生物活性多肽不仅降低豆清液排放,提高豆清液附加值提供技术支撑,同时为豆清液生物活性多肽的多元化使用提供来源。     

QuEChERS-气相色谱-串联质谱法测定鸡蛋中氟虫腈及其代谢产物

目的建立QuEChERS-气相色谱-串联质谱同时测定鸡蛋中氟虫腈及其代谢产物的方法。方法于5.0 g鸡蛋样品中加入3 ml水,加入10 ml乙腈提取,提取液经EMR-Lipids管净化。采用DB-5MS(30 m×0.25 mm,0.25μm)进行分离,多反应监测(MRM)模式进行检测,基质匹配曲线外标法定量。结果氟虫腈及其代谢产物在0～60μg/L范围内线性良好,相关系数(r)均≥0.999 0,检出限(S/N=3)为0.5～0.8μg/kg,定量限(S/N=10)为1.7～2.7μg/kg。回收率为92.0%～115.5%,相对标准偏差(RSD)为3.6%～6.8%(n=6)。结论该方法具有前处理方法简单、灵敏度高、回收率高等特点,适用于鸡蛋中氟虫腈及其代谢产物的准确检测。     

食品中氟虫腈的危害及检测方法研究进展

氟虫腈,又名锐劲特,是一种具有苯环结构的有机小分子,由法国罗钠-普朗克公司开发,获中国专利授权。氟虫腈是一种苯基吡唑类广谱杀虫剂,在水中溶解性较好。由于生产成本较低、杀菌效率高,因而被广泛应用于防治蔬菜、水稻、烟草、棉花、蓄牧业、公共卫生、贮存用品及地面建筑中各类别的作物害虫及卫生害虫。作为一类比较创新且性能好的的灭虫农药,氟虫腈曾在全国范围内乃至国际上被大量利用。欧盟法律规定,氟虫腈不得用于人类食品产业链的畜禽养殖过程。我国规定2009年10月1日起禁止使用含氟虫腈成分的农药制剂。欧盟委员会于2013年限制了氟虫腈在农作物保护中的使用。食品中氟虫腈的残留可通过食物链进行富集,对人体有较强的毒性,长期积累会诱发各种疾病。本文主要对氟虫腈的标准限量、应用、毒性及各种检测方法进行了综述,并在此基础上进行展望。     

Use of zeolite-containing biologically active food supplement in patients with burn trauma

The content of cationic protein in blood neutrophils, the serum activity of lysosomal enzymes, the intensity of peroxide lipid oxidation, the antioxidant serum activity and the blood concentration of trace elements were assessed in patients with burn injury. Some patients as addition to the main therapy got zeolyt-containing biological active addition to food (BAAF) "Lytovit" with its ability for sorption and selective ion exchange. Before the beginning of the treatment in all patients high value of the cationic protein degranulation, decrease of neutrophils biocidity, and increase of lipid peroxidation against a background of antioxidant activity were found. In patients, who had got zeolyt containing BAAF, the normalization of trace elements blood concentration and indices of neutrophils functional activity began earlier, then in patients without zeolyt containing biological active addition treatment. "Lytovit" promoted the more early regress of the clinic manifestations: the body temperature normalization, wounds self-cleaning from purulent discharge, diminishing of frequency and area of the grafts lysis.     

Changes in the content of biologically active polyamines during beef loin storage and cooking

Dietary polyamines putrescine (PUT), spermidine (SPD) and spermine (SPM) participate in numerous human physiological processes, including tumour growth. Reliable information on their contents in foods is thus needed. Data for processed beef are very limited. Nine experiments with beef loin (longissimus lumborum) were, therefore, carried out. Loin cuts were stored at −18 °C for 178 days or beef was stored aerobically, vacuum-packaged (VP) and packaged in a modified atmosphere (MA; 70% N₂ and 30% CO₂, v/v) at +2 °C for 9, 21 and 21 days, respectively. The effects of three usual cooking treatments were also tested. Polyamines were determined after extraction with perchloric acid as dansyl derivatives using an HPLC method. Only SPM was detected at initial levels of 23.5–27.5 mg kg⁻¹, PUT and SPD contents were below the detection limits of 1.2 and 1.7 mg kg⁻¹, respectively. SPM content increased during the initial weeks of frozen storage and then gradually decreased to about 70% of the initial values at the end of the storage period (P < 0.05). No apparent SPM decrease was observed during aerobic storage for 9 days, while in VP and MA variants the losses were about 20% of the initial values on day 21 (P < 0.05). Slightly higher mean SPM losses were observed during boiling and stewing with and without added water. The differences among the cooking treatments were not significant. However, significant differences were observed among the loins used.     

Cost effectiveness of regulation-compliant filtration to control sediment and metal pollution in urban runoff

The implementation of Total Maximum Daily Load (TMDL) to control urban runoff presents major structural and managerial challenges for cities. We developed a decision support system (DSS) for TMDL compliance at the city level to solve for a phased, least-cost strategy toward meeting four TMDLs using stormwater filtration. Based on a case-study city, we modeled wet weather flows and associated discharge of Total Suspended Sediment (TSS), cadmium, copper, and zinc to receiving waters by coupling U.S. EPA's Storm Water Management Model (SWMM v. 5.0) with the geographic dataset of the urban drainage network. We linked a mixed integer linear programming algorithm to the watershed model for deriving cost-effective selection and placement of curb inlet filters to meet mass- and concentration-based TMDL requirements. The least cost solution for meeting the city's TMDL waste load allocations for TSS (73.9% reduction), Cd (50.6% reduction), Cu (30.0% reduction), and Zn (55.7% reduction) would require 1071 filter inserts at a cost of $1.7 million. In contrast, random placement of 1071 filters or uniform placement of 1266 filters is effective only for TSS and would cost $4.0 million and $4.8 million, respectively. Our results demonstrate the increases in cost-effectiveness of using an optimization-based DSS for urban watershed management.     

2018年深圳市售蔬菜和鸡蛋中氟虫腈及其代谢物的检测分析

目的 建立超高效液相色谱-串联质谱法同时测定蔬菜和鸡蛋中氟虫腈及其代谢物(氟甲腈、氟虫腈砜和氟虫腈亚砜), 并对深圳市售的蔬菜和鸡蛋中氟虫腈及其代谢物残留状况进行抽样检测。方法 采用QuEChERS前处理方法, 以C18色谱柱为分离柱, 以乙腈和10 mmol甲酸+6 mmol甲酸铵水溶液为流动相进行梯度洗脱, 用超高效液相色谱-串联质谱(ultra performance liquid chromatography-mass spectrometry/mass spectrometry, UPLC-MS/MS), 电喷雾电离(electrospray ionization, ESI), 多反应监测(multiple reaction monitoring, MRM)模式检测, 外标法同时定量测定氟虫腈及其代谢物。结果 方法的线性范围为0.1~2.0 μg/L, 线性相关系数均大于0.9994, 检出限0.0005 mg/kg, 定量限0.001 mg/kg; 蔬菜中3个水平的平均加标回收率88.0%~101.2%, 相对标准偏差(relative standard deviation, RSD)均小于8.5%; 鸡蛋中3个水平的平均加标回收率86.1%~104.8%, 相对标准偏差(RSD)均小于9.2%。结论 该方法具有操作简单、干扰少、快速、准确可靠等特点, 可适用于蔬菜鸡蛋中氟虫腈及其代谢物的检测。