不同贝壳煅烧粉的杀菌及抑菌效果

目的:研究不同贝壳煅烧粉对致病菌的杀菌及抑菌效果。方法:将贻贝、文蛤、溢蛏3种贝壳高温煅烧1000℃,2 h,并配制成1%、0.1%、0.01%浓度的煅烧粉悬浊液,作用于沙门氏菌、副溶血弧菌、金黄色葡萄球菌以及大肠杆菌,利用菌液杀菌以及培养基扩散抑菌方法,检测3种贝壳煅烧粉对不同致病菌的杀菌及抑菌效果。结果:3种贝壳煅烧粉对4种菌均具有杀菌作用,对于革兰氏阴性菌的杀菌作用明显大于革兰氏阳性菌,作用最强为缢蛏及文蛤贝壳煅烧粉对副溶血弧菌,分别作用5 min后菌落总数小于10 CFU/mL。培养基扩散法的抑菌实验表明,3种贝壳煅烧粉对4种菌均有抑菌作用,抑菌效果最强为缢蛏贝壳煅烧粉在0.1 g/mL浓度下作用于沙门氏菌,抑菌圈直径达16.42 mm;在各浓度阶段,贻贝和文蛤贝壳煅烧粉对副溶血弧菌的抑菌性明显强于于沙门氏菌以及大肠杆菌。结论:贝壳煅烧粉对食源性致病菌杀菌及抑菌作用明显,可用作抑菌剂。     

鲍鱼壳煅烧物抗菌活性初步研究

研究鲍鱼壳煅烧物对几种常见致病菌的体外抗菌活性。采用滤纸片法和牛津杯双层琼脂扩散法测试不同温度段鲍鱼壳煅烧物对受试菌的抑制作用,并用琼脂梯度稀释法确定最小抑菌浓度(MIC)。结果表明:当煅烧温度段≥800℃,鲍鱼壳煅烧物对几种常见致病菌均有较强的抑制作用,尤其对金黄色葡萄球菌和铜绿假单鲍菌具有显著的抑制作用(p<0.05),MIC分别为1 mg/m L和0.5 mg/m L;并且在一定温度范围内,其对受试菌的抑制能力均随煅烧温度的升高而显著增加,在1100℃煅烧温度上抗菌效果最好。      

多孔隙牡蛎贝壳粉的制备及功效研究

目的:研究多孔隙牡蛎贝壳粉的生物功效.方法:采用高温煅烧制备多孔隙牡蛎贝壳粉,以柱层析除菌试验检测其除菌能力;以固相微萃取(SPME)技术结合GC-MS联机分析,检测贝壳粉对鱼肉中挥发性成分的影响.结果:用120目多孔隙牡蛎贝壳粉填直径为1.2 cm的柱子,柱高为1 cm时抑菌率可达82.3％,饱和时间50min时具有较强的除菌能力.脱臭前、后气味成分中烷烃类化合物峰面积减少率在80％以上.处理后3种海鱼鱼肉(小黄鱼、鲳鱼和带鱼)的挥发性物质中,二甲基甲胺的峰面积减少率分别为79.27％、100％和99.01％.结论:多孔隙牡蛎贝壳粉具有较强的除菌和脱臭能力,是一种有价值的生物过滤、除臭材料.     

水生蔬菜提取物的抗氧化活性分析及其对菜籽油的抗氧化作用

研究七种常见水生蔬菜不同部位提取物的抗氧化活性以及对油脂抗氧化的效果。采用ABTS自由基清除法、DPPH自由基清除法检测菱角、芡实、莲藕、水芋头、茭白、荸荠和慈姑不同部位的醇提物、水提物的抗氧化活性,烘箱法测定对菜籽油过氧化值的影响。在30种提取物中DPPH自由基清除能力较强的三种提取物IC50值分别为:芡实壳醇提物(0.03 mg/mL)芡实壳水提物(0.04mg/m L)=菱角壳醇提物(0.04mg/m L);ABTS自由基清除能力较强的三种提取物Trolox含量分别为芡实壳醇提物(1.42g/g)芡实壳水提物(1.41 g/g)菱角壳醇提物(1.15 g/g);添加0.1%浓度的五种提取物第7 d的POV值分别为23.86 meq/kg、24.06 meq/kg、23.53meq/kg、24.43 meq/kg、22.40 meq/kg,五种提取物的油脂抗氧化效果均不如0.1%浓度的BHA。30种水生蔬菜提取物中,芡实壳和菱角壳的醇提物、水提物DPPH自由基清除能力最强,芡实壳醇提物、水提物ABTS自由基清除能力最强;芡实壳水提物、芡实壳醇提物、菱角壳水提物、菱角壳醇提物以及藕节醇提物对菜籽油有一定抗氧化的效果,但效果弱于相同剂量的BHA。     

壳寡糖-金属配合物对太平洋牡蛎体内中Cd脱除效果的研究

目的:以太平洋牡蛎为实验对象,研究壳寡糖(chitosan oligosaccharide,COS)相对分子质量及脱乙酰度对COS-金属配合物脱Cd效果的影响,并对其应用条件进行优化。方法:将染Cd牡蛎养殖在含不同COS-金属配合物的天然海水中,定期取样,采用原子吸收法测定Cd含量的变化。结果:在COS-Ca、COS-Mg、COS-Zn和COS-Ree4种配合物中,COS-Mg的脱Cd效果最好。COS的相对分子质量和脱乙酰度对COS-Mg的脱Cd效果均有显著影响,其中当COS相对分子质量为2000、脱乙酰度为90%时COS-Mg对太平洋牡蛎的Cd脱除效果最佳,可达到28.20%。对COS-Mg配合物的应用条件进行了优化,当配合物质量浓度为100mg/L海水、脱除时间48h时,Cd脱除率最高(34.68%)。结论:COS-Mg配合物可有效降低牡蛎体内的Cd残留,是一种非常有潜力的贝类重金属残留脱除剂。     

贝壳粉对储粮霉菌抑制作用的研究

本研究通过直接粉碎、煅烧、酸处理和碱处理四种工艺制备贝壳粉,研究了贝壳粉对灰绿曲霉、黄曲霉、青霉、根霉和高大毛霉五种储粮霉菌的抑制效果,并进行了模拟储藏试验。研究结果表明:四种工艺制备的贝壳粉均具有良好的抑菌作用,抑菌能力由高到低依次为:酸处理、碱处理、煅烧、直接粉碎。本研究为贝壳粉在储粮行业的应用奠定了基础。     

栗壳抑菌物质的提取及其抑菌作用的研究

研究了栗壳提取物中抑菌物质的主要成分及其对常见食品污染菌的抑制作用,并且在食品体系中进行了初步防腐试验。以MCI为填料,采用柱层析法对栗壳粗提物进行初步分离,采用琼脂扩散法和常量肉汤稀释法考察栗壳提取物对4种细菌及2种霉菌的抑制作用。结果表明,栗壳提取物种主要抑菌成分可能为可水解单宁,栗壳单宁对大肠杆菌、金黄色葡萄球菌、枯草芽孢杆菌、沙门氏菌均有较明显的抑制作用,最低杀菌质量浓度为0.062 5~2.5 mg/m L,对黑曲霉,青霉孢子的最低杀菌质量浓度为20~40 mg/m L,对霉菌菌丝无抑制作用。食品防腐实验表明,同等质量浓度的栗壳单宁对苹果汁的防腐效果与苯甲酸钠基本相同。     

响应面法优化ClO_2溶液对牡蛎中沙门氏菌的杀菌动力学

为了探究ClO_2溶液处理牡蛎中沙门氏菌的最佳杀菌条件,本文选用鼠伤寒沙门氏菌(CICC22956)和肠炎沙门氏菌(CICC21482)混合菌株,在单因素实验的基础上,运用响应面实验设计方法探讨料液比、ClO_2溶液浓度和杀菌时间对牡蛎中的沙门氏菌杀菌效果的影响。通过响应面优化模型确定ClO_2溶液杀菌的最佳条件为:料液比1∶7g/mL,ClO_2浓度93g/mL,杀菌时间30min。在此条件下模型优化出最优的沙门氏菌菌落降低值为3.13lgcfu/g。实验结果表明,采用上述分析的最佳条件不仅有效防止牡蛎中沙门氏菌的污染,还可以提高生鲜牡蛎的品质和安全性。     

植物提取物对芒果致腐菌的抑制作用研究

对植物提取物在抑制芒果病害领域进行了初步研究。以芒果褐色蒂腐菌(Phomopsis mangiferae Ahmad)和胶孢炭疽菌(Collgtotrichum gloeospo rioides Penz)为研究对象,采用管蝶法评价30种植物的水提物和醇提物的离体抑菌效果。并使用孔板连续培养法测定相应的最低抑菌浓度(MIC)和最低杀菌浓度(MBC)。结果表明:有14种水提物和7种醇提物对芒果致腐菌有抑制作用。其中丁香、肉豆蔻、金银花、知母、白芷、虎杖、乌梅、牡丹皮、黄连、藿香的水提物以及肉豆蔻、黄岑、大黄、桂皮、丁香的醇提物对胶孢炭疽菌均有抑制效果;丁香、桂皮、金银花、牡丹皮、知母、肉豆蔻的水提物以及肉豆蔻、芦荟、大茴香的醇提物对褐色蒂腐菌有不同程度的抑制作用。      

植物提取物对芒果致腐菌的抑制作用研究

对植物提取物在抑制芒果病害领域进行了初步研究。以芒果褐色蒂腐菌(Phomopsis mangiferae Ahmad)和胶孢炭疽菌(Collgtotrichum gloeospo rioides Penz)为研究对象,采用管蝶法评价30种植物的水提物和醇提物的离体抑菌效果。并使用孔板连续培养法测定相应的最低抑菌浓度(MIC)和最低杀菌浓度(MBC)。结果表明:有14种水提物和7种醇提物对芒果致腐菌有抑制作用。其中丁香、肉豆蔻、金银花、知母、白芷、虎杖、乌梅、牡丹皮、黄连、藿香的水提物以及肉豆蔻、黄岑、大黄、桂皮、丁香的醇提物对胶孢炭疽菌均有抑制效果;丁香、桂皮、金银花、牡丹皮、知母、肉豆蔻的水提物以及肉豆蔻、芦荟、大茴香的醇提物对褐色蒂腐菌有不同程度的抑制作用。     

解淀粉芽孢杆菌YP6对三种贝壳粉的促磷研究

研究了一株从贵州磷矿植物根际分离的溶磷菌Bacillus amyloliquefaciens YP6(YP6)的促生性能及其在贝壳粉和土壤溶磷中的作用。结果表明,菌株YP6具有较好的促生作用,并且经YP6发酵贝壳粉(牡蛎粉,蛤蜊粉和生蚝粉)、土壤和贝壳粉的混合物在第7天样品中可溶磷质量浓度分别为44.9、39.2、40.3、86.4、73.1、74.8 mg/L。说明YP6对土壤和3种贝壳粉均具有显著的溶磷作用。     

Use of oyster shell as calcium supplement. Part 2. An assessment of the responses of hepatic and serum enzymes, relative organ weights, and bone mineralization in the broiler chicken fed gossypol-containing cottonseed cake supplemented with oyster shell

The role of oyster shell as calcium supplement in the utilization of gossypol-containing cottonseed cake (CSC) was assessed using Hypeco broiler chickens. The results showed that of the organ measured, only the relative weight of the spleen was significantly (P less than 0.05) decreased by oyster shell supplementation in the CSC diets. Spleen weight correlated negatively (r = -0.45) with dietary calcium. Alkaline phosphatase activity in the liver was significantly (P less than 0.05) increased due to the levels of oyster shell supplemented while the activities of serum and liver alanine aminotransferase and aspartate aminotransferase were not significantly influenced. The results also showed that although oyster shell supplementation generally increased alkaline phosphatase activity, bone mineralization was relatively uninfluenced as judged by the low coefficients of variation (CV) of 3.14-3.51% and 3.39-4.82% for calcium and phosphorus content in the femur and tibia respectively.     

基于高通量测序技术的牡蛎壳粉缓解骨质疏松症的研究

目的:探究牡蛎壳粉对糖皮质激素性骨质疏松小鼠的缓解作用。方法:将ICR雌性小鼠随机分为对照组、模型组、碳酸钙组和牡蛎壳粉组,肌肉注射地塞米松（1 mg/kg/d）构建骨质疏松小鼠模型,分析股骨微结构、血清钙、粪便钙、股骨钙、骨转换指标和肠道菌群变化。结果:牡蛎壳粉能显著提高骨密度和骨小梁厚度（P<0.05）并降低骨小梁分离度和结构模型指数,改善骨微结构,显著降低血清钙含量（P<0.001）。牡蛎壳粉也能显著升高血清中碱性磷酸酶酶活（P<0.001）,降低抗酒石酸酸性磷酸酶酶活（P<0.01）;显著升高骨形成标记物碱性磷酸酶和骨保护素的基因转录（P<0.05）,降低骨吸收标记物抗酒石酸酸性磷酸酶和硬骨素的基因转录（P<0.05）。牡蛎壳粉还能改变小鼠肠道菌群结构,增加约氏乳杆菌、产粪甾醇真细菌等的丰度。嗜酸乳酸杆菌、豚鼠乳杆菌、罗伊氏乳杆菌、产酸拟杆菌与骨形成指标显著负相关,而与骨吸收指标显著正相关。结论:牡蛎壳粉能够抑制骨矿物质流失,提高骨密度和骨小梁厚度,促进骨形成指标而抑制骨吸收指标,改善肠道菌群,从而有效缓解骨质疏松。     

牡蛎的生物活性及其食品的开发研究进展

为了充分认识牡蛎,介绍了牡蛎具有降血糖、增强免疫力,降血压、抗疲劳、抗肿瘤和保肝等生物活性功能,牡蛎的功能性产品的开发现状有牡蛎肉食品和牡蛎壳保健食品,超微粉碎技术、生物技术、超声波技术和超高压技术等高新技术在开发功能性牡蛎食品中的应用现状,并分析了功能性牡蛎食品的开发前景和存在的问题。     

Patterns in volatile components over heated fish powders

Freeze dried powders of herring and blue whiting filets were heated for 0.5–4 h at 40 to 140 °C. The volatile components over the powders were analysed by solid phase micro extraction and gas chromatography–mass spectrometry.Principal component analysis was performed on the chromatographic areas. The patterns over the heated samples showed evolution with temperature exposure along one gradient, indicating that heating at high temperature over a short time interval can produce a similar pattern as heating at a lower temperature for a longer time interval.The response to heating was similar for both herring and blue whiting powders, and a common model based on partial least squares regression was developed for prediction of the temperature exposure. Chemical markers for evaluation of the temperature exposure in a heated fish powder were found. The best markers were pyridines, pyrazines, aromatic hydrocarbons, amides and selected volatile sulfur compounds.     

Shape similarity measure using turn angle cross-correlation for oyster quality evaluation

An overview of the oyster industry in the US shows that oyster grading occurs at harvest, wholesale, and processing markets. Currently whole oysters, also called shellstock, are graded manually by screening and sorting based on diameter or weight, which does not concern shape appearance. However, studies show that customers prefer oysters that are round and 2 in. in diameter. This paper presents a simple and accurate shape analysis method for size and shape-based oyster grading. The proposed algorithm is currently programmed to perform shape analysis to grade oysters into good quality, banana, and irregular grades and can be extended to accommodate other grades acceptable for market. Other shape categories can be added with a simple configuration procedure. The contour of the oyster is extracted and its data points are reduced to 50 points using either curve evolution and fixed interval sub-sampling data reduction methods. A simple and accurate shape similarity measure method called turn angle cross-correlation (TAC) is developed to categorize oyster shell shape and other similar applications. Experimental result shows that this method performs well and is suitable for commercial use.     

板栗壳天然棕色素的稳定性研究

本文研究了板栗壳棕色素对光照、温度、还原剂、氧化剂、金属离子、pH值和常用食品添加剂和配料如葡萄糖、蔗糖、柠檬酸、防腐剂等的稳定性，为板栗壳色素的开发应用提供理论依据。     

Characterization of Oyster Shucking Liquid Wastes and Their Utilization as Oyster Soup

Liquid wastes including shell liquor, bled liquor, original liquid and wash water were collected from laboratory and commercial oyster shucking operations and were characterized physically and chemically. These liquid wastes contained 0.01 to 0.36% nonprotein-N components, 0.03 to 0.44% total-N, 0.13 to 1.64% salt and an identical protein profile with molecular weights around 20kD to 25kD as major proteins. Total solids could be used to predict the levels of total-N, nonprotein-N, ash, salt, total suspended solids and COD. Steam-jacketed kettle heating was an easy method to concentrate liquid wastes for production of oyster soup. Chemical, physical and sensory properties of processed oyster soup were analyzed and compared with a commercial product.     

Effect of pretreatments and drying methods on physico‐chemical,sensory characteristics and nutritional value of oyster mushroom

This study was aimed to evaluate the effect of pretreatments and drying methods on the chemical, physico‐chemical, sensory characteristics and nutritional value of oyster mushroom. Chemical analysis of oyster mushroom (OM) showed that the values content were increased by many times when calculated on dry weight basis. Nine treatments of dried mushroom powders (DMP) were prepared using three drying methods (hot air drying, vacuum drying, and sun drying). Also, three pretreatments of each method of drying were used (untreated, blanching by steaming without or with steeped in 0.5% citric acid solution for 30 min).The results and statistical analysis revealed that, sun dried oyster mushroom samples (without pretreatments) were found to be the best. The DMP samples resulting of the sun drying had a highest physico‐chemical properties, sensory evaluation scores, and contents of the mineral elements and amino acids as compared to other pretreatments and drying methods.

Practical applications

Fresh mushrooms have high water content, high enzymatic activity and hence are highly perishable. Thus, in this study nine treatments of dried mushroom powders (DMP) were prepared using three drying methods (hot air drying, vacuum drying and sun drying).Also, three pretreatments of each method of drying were used (untreated, blanching by steaming without or with steeped in citric acid).The DMP samples (untreated) resulting of the sun drying were better than other pretreatments and drying methods regarding quality attributes.