Food preservatives sodium sulfite and sorbic acid suppress mitogen-stimulated peripheral blood mononuclear cells

Antioxidant preservatives prolong the quality of food and ensure the nutritional adequacy, palatability and safety of many processed foods and beverages. Effects of sodium sulfite (E221) and sorbic acid (E200) were investigated in human peripheral blood mononuclear cells (PBMC) which were purified from blood of healthy donors. Cells were stimulated with the mitogen phytohaemagglutinin in vitro, which induces proliferation of T-cells and the production of Th1-type cytokines like interferon-γ. The latter triggers enzyme indoleamine (2,3)-dioxygenase, which degrades tryptophan, and GTP cyclohydrolase I, which leads to increased neopterin production, in monocyte-derived macrophages. Sodium sulfite and sorbic acid suppressed both these biochemical changes in a dose-dependent way (P < 0.01 at 1 mM sodium sulfite and 50 mM sorbic acid). Data demonstrate a suppressive influence of sodium sulfite and sorbic acid on the activated Th1-type immune response.     

Public health decisions: Actions and consequences

The goal of public health is to promote the best possible health for the whole population. Public health issues are numerous and can be unbelievably complex in form, scope, and possible consequence. Most public health decisions involve assessing several different options, weighing the respective benefits and risks of those options, and making difficult decisions that hopefully provide the greatest benefit to the affected populations. Many risk management decisions involve a variety of societal factors which modify risk assessment choices. The purpose of this paper is to point out difficulties in making decisions that impact public health. The intent of such decisions is to improve public health, but as illustrated in the paper, there can be unintended adverse consequences. Such unplanned issues require continued attention and efforts for responsible officials in the protection of environmental public health. This article presents examples of such events, when in the past, it was necessary to assess and regulate a number of potentially hazardous chemicals commonly used as insecticides, gasoline additives, and wood preservatives.     

Improved food additive analysis by ever-increasing nanotechnology

Improper use of food additives may lead to potential threat to human health, making it important to develop sensitive and selective method for their detection. Nanomaterials with unique chemical and electrochemical properties show extensive applications in the design of food additive sensing systems. In this review, we summarize the recently adopted electrochemical and optical analysis of food additives based on nanomaterials. Detection of typical food additives (colorants and preservatives) by using different sensing mechanisms and strategies are provided. In addition, determination of illegal food additives is also briefly introduced. Finally, this review highlights the challenges and future trend of nanomaterial-based food analysis system.     

复方鱼腥草合剂中3个有效成分及防腐剂的含量测定

目的 考察市售复方鱼腥草合剂的质量。方法 收集10批不同厂家生产的复方鱼腥草合剂,应用HPLC测定3个有效成分（绿原酸、连翘酯苷A、黄芩苷）及防腐剂（苯甲酸钠、羟苯乙酯）含量。结果 10批复方鱼腥草合剂中绿原酸的含量为29.74~84.13μg·mL^-1、连翘酯苷A的含量为22.69~113.44 μg·mL^-1、黄芩苷的含量为0.587~1.662 mg·mL^-1;苯甲酸钠和羟苯乙酯含量均符合标准规定。结论 复方鱼腥草合剂质量情况较乐观,但是不同批次内在质量有较大差异,现行标准的质量控制方法较简单,不能有效控制其质量,建议修订完善标准。     

N-hydroxymethylglycinate with EDTA is an efficient eye drop preservative with very low toxicity: an in vitro comparative study

Purpose: Preservatives are used in multi-dose ophthalmic topical medications in order to prevent contamination by bacteria and fungi. However, prolonged use of preserved eye drops, as it may happen in dry eye or glaucoma, may damage cells of the ocular surface. Therefore, an important goal is to find preservatives with low toxicity which are mild to host cells, still able to prevent drug contamination so to maintain their sterility and efficacy. Hence, aim of this study has been to compare the relative toxicity on a rabbit corneal cell line of a new preservative, made by the association of N-hydroxy-methyl-glycinate (NIG) with disodium-ethylene diamine tetra-acetate (EDTA), with other known and widely used eye-drops preservatives.

Materials and methods: Rabbit corneal cells (SIRC) were tested either in 96-well plates or in suspension culture. Treatments with preservatives (used at known bacteriostatic concentrations) included: benzalkonium chloride (BAK), polyquaternium-1 (PQ-1), sodium perborate (SP: NaBO_{3 *} H₂O), and NIG?±?EDTA at different concentrations (0.001% and 0.002%), and different treatment times (from 30?minutes to 120?hours). At the end of treatment, cell survival was evaluated by a specific spectrophotometric method through the metabolic conversion of MTT [3-(4,5-dimethylthiazol-2-yl) 2, 5-diphenyltetrazolium bromide] into formazan crystals.

Results: Almost no cell toxicity was evident for NIG and SP at either concentration (0.001% or 0.002%), while a low toxicity was observed for PQ-1 (62% at the highest dose at 120?hours). BAK, as expected, showed the highest toxicity (60–80% at 30?minutes, and over 90% from eight hours onward). EDTA 0.1% alone or in combination with NIG 0.002%, showed no toxicity at 24?hours, and even resulted in cell growth promotion (46% and 38%, respectively), after 48?hours of treatment.

Conclusions: These data show that the new preservative NIG/EDTA, at doses known to have effective antimicrobial properties, has a very low toxicity on corneal cells, and so it can be safely used in multi-dose eye drops.     

珍珠明目滴眼液中防腐剂尼泊金乙酯的含量测定

目的 建立HPLC法测定珍珠明目滴眼液中防腐剂尼泊金乙酯的含量.方法 以十八烷基硅烷键合硅胶为填充剂;甲醇-水（78：22）为流动相;检测波长：254 nm;流速：1.0 mL· min^-1;柱温：35℃.结果 珍珠明目滴眼液中防腐剂尼泊金乙酯在96.10～961.0 ng范围内呈良好的线性关系（r=0.9999）,最小检出量为0.227 ng,平均回收率为99.06％（n=6）,RSD为0.27％.结论 本方法经方法学验证适用于珍珠明目滴眼液质量控制,可为该品种标准提升作参考.     

Comparison of preservative-free and preservative-containing ipratropium bromide

Abstract A double-blind crossover study was performed on 33 children with asthma to compare the effectiveness of nebulized solutions of preservative-containing and preservative-free ipratropium bromide. Both solutions produced bronchodilation. No significant differences were found between the two solutions at any time after nebulization in minimum and maximum changes from baseline value or in the areas under the lung function time curves. The presently formulated preservative-containing ipratropium bromide solution was not shown to be inferior to a preservative-free compound.     

An assessment of the comparative sensitization potential of some common isothiazolinones

The isothiazolinones are known contact sensitizers. Data are presented which demonstrate that, in comparison with the chlorinated and dichlorinated compounds which share immunological cross-reactivity, the unchlorinated isothiazolinones have a lower potential for sensitization and no documented immunological cross-reaction with the chlorinated isothiazolinones.