三种新型防座剂抗菌性能的研究

对山梨酸及本实验室最新合成的三种防腐剂的抗菌性能进行了研究，发现溴代山梨酸比山梨酸具有更强的抗菌强度和抗代谢能力，反丁烯二酸桂醇甲酯的抑菌强度最强，而且几乎不受介质pH的影响，二者均有很好的应用前景，反丁烯二酸桂醇酯则由于溶解性等方面的原因，抑菌强度较低，但其半衰期较长，下一步可从增强其水溶性角度对其进行分子改造以提高其抗菌性能。     

反丁烯二酸蔗糖甲酯的功能特性研究

基于防腐防霉剂的构效关系和乳化剂的分子结构特点，合成了反丁烯二酸蔗糖甲酯。抑菌实验表明：对几种常见微生物，酯化度为5．5的反丁烯二酸蔗糖甲酯的最低抑菌浓度比山梨酸的低而接近于富马酸二甲酯，说明其具有较高的抗菌活性；反丁烯二酸蔗糖甲酯的抗菌半衰期要长于山梨酸和富马酸二甲酯，说明其抗代谢性能好，具有一定的开发应用价值。乳化实验表明：酯化度为5．5的反丁烯二酸蔗糖甲酯的HLB值为6．8、临界胶束浓度为0．7g，L、浓度为0.3％溶液的表面张力为28．5mN/m，都接近于span-80，说明反丁烯二酸蔗糖甲酯具有一定的表面活性。有关反丁烯二酸蔗糖甲酯的抗菌特性及乳化特性在食品、日化及涂料等工业领域的应用有待于进一步研究。     

反丁烯二酸桂醇甘醇酯的合成及抗菌作用研究

由于烯二酸酐经醇解转型酯化途径合成了对皮肤无过敏反应的反丁烯二酸桂醇甘醇酯（SGF）。质子酸型酯化催化剂和提供空轨道分子型酯化催化剂对SGF合成具有显著的增效催化作用。依酯化反应的进行，流加硫酸降低反应体系中的水分活度，可有效提高SGF的合成率。所合成的SGF可显著抑制微生物的生长、延长适应期、缩短对数生长期和稳定期、促进微生物细胞的自溶作用。     

反丁烯二酸芳香醇酯的合成及抑菌活性研究

本文合成了一系列的反丁烯二酸芳香醇(苄醇、苯乙醇、苯丙醇、邻溴苄醇)酯,所得产物的NMR、FTIR表征结果与理论预测一致。用光电比浊法研究其抑菌活性,反丁烯二酸芳香醇酯表现出较强的抑菌活性,随着芳香醇的链长的增加对四种细菌的抑制作用也增强,芳香醇卤代后,与反丁烯二酸所生成的二酯的抑菌作用也得到加强。反丁烯二酸芳香醇酯有望成为高效抑菌剂。     

反丁烯二酸蔗糖甲酯合成及抗菌特性研究

利用固体超强酸SO2-4/TiO2催化合成反丁烯二酸蔗糖甲酯(SMF),反应分为3步:马来酸酐先和蔗糖反应生成顺丁烯二酸单蔗糖酯、顺丁烯二酸单蔗糖酯异构化和反丁烯二酸单蔗糖酯与甲醇酯化反应生成SMF。用单因素法确定了"一锅法"合成SMF的工艺。研究了酯化度为5.5的SMF的最低抑菌浓度和生长抑制曲线,并与山梨酸及富马酸二甲酯进行了对比。结果表明:SMF具有较广的抗菌谱系,对细菌、酵母和霉菌的生长具有较强的抑制能力。添加0.12%的SMF可使大肠杆菌和苏云金杆菌的生长适应期分别由对照的3h延长至30h和35h;添加0.10%的SMF能使酵母的生长适应期延长至对照(5h)的6倍,添加0.06%SMF,液体培养96h后才有黑曲霉菌丝球出现,而对照样20h即可见到。反丁烯二酸蔗糖甲酯的抑菌效果好于山梨酸而与富马酸二甲酯接近。     

溴代山梨酸的合成与抗菌作用研究

针对山梨酸使用过程中存在的问题 ,首次合成了溴代山梨酸 ,研究了它对不同种类微生物的抗菌性能 ,并与山梨酸的抗菌性能进行了比较。山梨酸经化学修饰合成溴代山梨酸后 ,抗菌作用显著增强 ,抗菌作用稳定性显著提高 ,半衰期延长了 3 3倍 ,在水中溶解性得到明显改善 ,具有一定的开发应用前景     

水溶性山梨酸的开发及其抑菌性能的研究

采用高效乳化技术开发水溶性分子态山梨酸,建立水溶性分子态山梨酸生产工艺,研究了乳化剂乳化温度、均质速度,以及乳化剂种类对水溶性分子态山梨酸产率的影响,并通过比较其对几种常见微生物的最低抑制浓度研究其抑菌性能.结果表明采用复合乳化剂、均质速度为15000r/min、乳化温度为40℃,所制备的水溶性山梨酸中山梨酸的含量为18.2%,所制备的水溶性山梨酸抑菌能力是山梨酸钾的10倍.     

壳聚糖山梨酸酯的合成、表征及抑菌活性研究

通过2步反应合成了壳聚糖山梨酸酯。第1步,山梨酸在氯化亚砜中回流制备山梨酰氯;第2步,壳聚糖与山梨酰氯在甲烷磺酸的催化下酯化合成了壳聚糖山梨酸酯衍生物。采用红外光谱(FT-IR)和核磁共振氢谱(1H NMR)对衍生物的结构进行了表征。结果表明,壳聚糖的羟基与山梨酰氯发生了取代反应,其氨基仍以游离形式存在。在不同的反应物比例下,制备了取代度(DS)分别为0.44、1.21、1.93的3种衍生物,抑菌实验的结果显示:取代度为1.21的壳聚糖山梨酸酯对大肠杆菌、金黄色葡萄球菌和黑曲霉抑制作用最强,最小抑菌浓度分别为0.125,0.125和0.5 g/L。壳聚糖山梨酸酯的抑菌活性远高于壳聚糖,具备作为防腐剂在食品中应用的基础。     

科学家将壳聚糖、有机酸及其纳米级胶体用于食品抗菌包装材料

据sciencedirect数据库消息,2013年6月《食品控制》(Food Control)刊登一项壳聚糖、有机酸及其纳米级胶体在食品抗菌包装材料中潜在应用的研究。研究人员将低分子量及中分子量的壳聚糖及有机酸(苯甲酸、山梨酸、纳米级苯甲酸-山梨酸胶体)抗菌活性进行对比。研究结果表明,壳聚糖抗菌活性受其分子量的影响,低分子量及中分子量壳聚糖最低抑菌浓度(w/v)分别为0.010%、0.015%,纳米级苯甲酸-山梨酸胶体抗菌活性显著高于其非纳米级胶体。纳米级胶体抗菌剂可以使用更少的抗菌物质达     

离子型反丁烯二酸单甲酯的合成及抑菌活性研究

以顺丁烯二酸酐和甲醇为原料合成了反丁烯二酸单甲酯,通过正交试验考察了催化剂的用量、异构化时间及异构化温度对产率的影响。结果表明,反应原料顺丁烯二酸酐与甲醇物质的量比为1.1:1(摩尔比),在60℃下反应1h 实现单酯化后,加入10.9% 的三氯化铝在80℃下进行转型2h,产率为71.9%。并通过交叉融合法合成了离子型反丁烯二酸单甲酯,用熔点测定法、红外光谱法和NMR 对产品进行了鉴定。同时采用比浊法、平板法测定离子型反丁烯二酸单甲酯对细菌、霉菌、酵母的抑菌效果。结果表明离子型反丁烯二酸单甲酯对它们均有较强的抑菌活性,有望开发成为新型抑菌剂。     

Naturally occurring benzoic,sorbic, and propionic acid in vegetables

ABSTRACT

Benzoic, sorbic and propionic acid are used as preservatives in foods and can also be naturally present in processed foods. The levels of preservatives in 939 vegetables were determined. Benzoic and sorbic acid were analysed by high-performance liquid chromatography with a diode-array detector and further confirmed by liquid chromatography-tandem mass spectrometry, whereas propionic acid was analysed using a gas chromatography-flame ionization detector and further confirmed by gas chromatography-mass spectrometry. Benzoic and propionic acid were found in 10.9% and 36.2%, respectively, of the samples. In contrast, sorbic acid was not found in any of the samples. The highest amounts of benzoic and propionic acid were found in perilla leaves (0.33?298 mg kg^–1) and ginseng (<LOD?32.8 mg kg^–1), respectively. The background concentration ranges of naturally occurring preservatives in vegetables determined in this study could be used for inspection services of standard criteria to address consumer complaints or trade disputes.     

对羟基苯甲酸酯衍生物的抗菌活性及其发展趋势

介绍了新型高效食品防腐剂对羟基苯甲酸酯衍生物的抗菌活性，阐述了对羟基苯甲酸酯衍生物的生产现状和在食品工业应用研究的发展趋势。     

Sorbic,benzoic and propionic acids in fishery products: a survey of the South Korean market

This study was conducted to provide basic data as part of a project to distinguish naturally occurring organic acids from added preservatives. Accordingly, we investigated naturally occurring levels of sorbic, benzoic and propionic acids in fish and their processed commodities. The levels of sorbic, benzoic and propionic acids in 265 fish and their processed commodities were determined by high-performance liquid chromatography–photodiode detection array (HPLC-PDA) of sorbic and benzoic acids and gas chromatography-mass spectrometry (GC/MS) of propionic acid. For propionic acid, GC-MS was used because of its high sensitivity and selectivity in complicated matrix samples. Propionic acid was detected in 36.6% of fish samples and 50.4% of processed fish commodities. In contrast, benzoic acid was detected in 5.6% of fish samples, and sorbic acid was not detected in any sample. According to the Korean Food and Drug Administration (KFDA), fishery products and salted fish may only contain sorbic acid in amounts up to 2.0 g kg^?1 and 1.0 g kg^?1, respectively. The results of the monitoring in this study can be considered violations of KFDA regulations (total 124; benzoic acid 8, propionic acid 116). However, it is difficult to distinguish naturally generated organic acids and artificially added preservatives in fishery products. Therefore, further studies are needed to extend the database for distinction of naturally generated organic acids and added preservatives.     

草莓保鲜剂的开发研究

目的 探讨不同类型保鲜剂对草莓采摘后的保鲜效果。方法 将草莓置于蒸馏水、生姜提取液、甘草-壳聚糖溶液中浸泡1 min, 探讨保鲜剂对草莓感官、营养、生化指标等的影响。结果 与对照组相比, 2种保鲜剂都能显著抑制草莓失重、腐烂, 也能延缓维生素C和可滴定酸含量下降, 抑制超氧化物歧化酶和过氧化物酶活性损失, 但甘草-壳聚糖保鲜效果更好。贮藏6 d后, 甘草-壳聚糖组比空白对照组可滴定酸含量高72.90%, 维生素C含量高93.79%, 过氧化物酶活性高233.01%, 超氧化物歧化酶活性高187.47%。结论 甘草-壳聚糖作为保鲜剂, 能有效地延长草莓贮藏期。     

天然保鲜剂对预制南美白对虾贮藏品质的影响

为研究阿魏酸、绿原酸、咖啡酸三种天然保鲜剂对预制南美白对虾冷藏（4℃）期间品质变化影响,以菌落总数（Total Bacterial Count,TBC）、挥发性盐基氮（Total Volatile Base Nitrogen,TVB-N）、pH、硫代巴比妥酸值（Thiobarbituric Acid Reactive Substances,TBARS）、剪切力等为考察指标,结合表观性状综合评价作用效果。结果表明,与对照组样品相比,三种天然保鲜剂均可抑制预制南美白对虾冷藏期间TBC、TVB-N、TBARS值的升高,延缓质地软化,保持较好的感官品质,且作用效果与浓度正相关。pH与TBARS的变化趋势相似,且显著正相关（r=0.997,P<0.05）。在三种天然保鲜剂中,绿原酸处理对预制南美白对虾冷藏抑菌效果最佳,咖啡酸处理对其质地保护能力最佳,阿魏酸能明显抑制虾肉蛋白降解、质地变软,延缓虾体黑变。与对照组样品冷藏货架期5 d相比,使用1%阿魏酸、绿原酸、咖啡酸处理后,预制南美白对虾冷藏货架期分别延长至14、12、12 d。     

产细菌素乳酸菌的选育及其抑菌特性的研究

采用牛津杯琼脂扩散法,从实验室保存的乳酸菌中筛选到具有较高抑菌活性的菌株嗜酸乳杆菌A、戊糖片球菌M和戊糖片球菌T,它们产生的抑菌物质经排除酸、过氧化氢后,仍具有抑菌活性,然而经蛋白酶处理后其抑菌活性明显下降,确定其抑菌物质为细菌素,进一步的抑菌实验表明,3株菌所产细菌素具有较宽的抑菌谱,适宜用作生物型防腐剂。     

乳酸菌细菌素抑菌特性及在食品中的应用研究进展

乳酸菌细菌素是细菌在核糖体上合成的具有抗菌活性的多肽类物质,这些细菌素能杀灭或抑制引起食品腐败的细菌的繁殖,可作为天然的食品防腐剂在食品中应用。该文综述了乳酸菌细菌素的分类、国内外研究现状、抑菌特性及应用等方面的最新研究进展,并对乳酸菌细菌素未来研究趋势进行简要分析,对乳酸菌细菌素在食品中的应用有一定参考价值。     

壳聚糖复合涂膜常温保鲜草莓的研究

采用菌丝生长速率法筛选出对草莓采后主要病原菌抑制效果最佳的中草药复合物,并将其与涂膜剂壳聚糖、助剂抗坏血酸(VC)、抗氧化剂植酸复配成复合保鲜剂,通过正交实验确定了各组分的最佳浓度配比:复合中草药提取物0.3%(丁香、蛇床子、补骨脂的质量比为1:1:1)、壳聚糖1.25%、VC1.25%、植酸0.05%。草莓经此复合保鲜液处理后,显著降低了常温贮藏期间的失重率、腐烂率,延缓了可溶性固形物、VC和可滴定酸含量的下降,且各项保鲜指标均优于1.25%壳聚糖的单独涂膜处理。     

Exposure assessment of food preservatives (sulphites,benzoic and sorbic acid) in Austria

An exposure assessment was performed to estimate the potential intake of preservatives in the Austrian population. Food consumption data of different population groups, such as preschool children aged 3–6 years, female and male adults aged 19–65 years were used for calculation. Levels of the preservatives in food were derived from analyses conducted from January 2007 to August 2010. Dietary intakes of the preservatives were estimated and compared to the respective acceptable daily intakes (ADIs). In the average-intake scenario, assuming that consumers randomly consume food products that do or do not contain food additives, estimated dietary intakes of all studied preservatives are well below the ADI for all population groups. Sulphite exposure accounted for 34%, 84% and 89% of the ADI in preschool children, females and males, respectively. The mean estimated daily intake of benzoic acid was 32% (preschool children), 31% (males) and 36% (females) of the ADI. Sorbic acid intakes correspond to 7% of the ADI in preschool children and 6% of the ADI in adults. In the high-intake scenario assuming that consumers always consume food products that contain additives and considering a kind of brand loyalty of consumers, the ADI is exceeded for sulphites among adults (119 and 124%, respectively). Major contributors to the total intake of sulphites were wine and dried fruits for adults. Mean estimated dietary intakes of benzoic acid exceeded the ADI in all population groups, 135% in preschool children, 124% in females and 118% of the ADI in males, respectively. Dietary intakes of sorbic acid are well below the ADI, accounting for a maximum of 30% of the ADI in preschool children. The highest contributors to benzoic and sorbic acid exposure were fish and fish products mainly caused by high consumption data of this large food group, including also mayonnaise-containing fish salads. Other important sources of sorbic acid were bread, buns and toast bread and fruit and vegetable juices.     

抗真菌乳酸菌研究

食品安全是近年来公众关注的焦点,常规的食品防腐剂由于其可能的致癌致畸副作用,促使人们寻找可替代的天然安全防腐剂。乳酸菌具有充当天然防腐剂的潜质和优势,其抗真菌研究是当前研究的热点。人们经过研究发现乳酸菌可以产生有机酸、肽类及脂肪酸等抗真菌类物质。本文就当前抗真菌乳酸菌研究进行综述,对不同抗真菌物质进行详细阐述,并对后续研究进行展望。