电位滴定法测定蜂胶软胶囊酸价

目的探索蜂胶软胶囊的酸价测定方法。方法根据蜂胶软胶囊的处方,取蜂胶粉、白蜂蜡、植物油脂、抗氧化剂、不含蜂胶粉的混合油脂(内含白蜂蜡、植物油脂、抗氧化剂)、蜂胶软胶囊,分别用方法 1和方法2测定酸价,以10 g/L酚酞溶液或电位滴定仪指示终点。结果方法 1,因蜂胶粉的干扰而无法测定蜂胶软胶囊的酸价;方法 2,以10 g/L酚酞溶液指示终点时,在滴定过程中会出现黄色,影响终点的判断,采用电位滴定仪指示终点,指示效果明显,能得到良好的精密度。按方法 2测定蜂胶软胶囊酸价,用电位滴定仪指示终点,测得不同批次样品重复测定结果的精密度为0.9%~2.6%,不同批次样品不同时间测定结果的精密度为2.4%~3.7%,测得回收率为95.6%~105.0%,平均回收率为100.0%,RSD(%)为3.5%。结论采用方法 2,用电位滴定仪指示终点,能够很好消除蜂胶软胶囊内容物中蜂胶粉对蜂胶软胶囊酸价测定的干扰,测定结果精密度良好,准确度高,能对蜂胶软胶囊的酸价起到质量控制的目的。     

紫外辐照对蜂胶/纳米SiO2复合膜性能的影响

本文以拉伸强度(TS)、断裂伸长率(E)、透光率(T)、溶解度(S)、水蒸气透过性(WVP)和氧气透过性(OP)等为品质指标,研究了紫外辐照对蜂胶/纳米SiO2复合膜品质的影响。研究显示:随着辐照时间的延长,复合膜的TS和S先升高后降低、E和OP先降低后升高、T和WVP先降低后逐渐趋于不变,且紫外处理12 h复合膜的TS达到了最大值,较对照组提高了3.07 MPa,当辐照时间达到16 h时,S达到最大值,较对照组提高了5.68%,E、T、WVP和OP均在16 h时达到最小值,分别较对照组分别降低了2.88%、4.33%、2.13 g/(cm·s·Pa)和0.5 cm3/(m2·24 h·0.1 MPa)。通过主成分聚类分析法对试验结果进行多指标分析,结果显示,当辐照时间为16 h时,复合膜的综合得分最高,即此时复合膜的综合性能最好,这与单因素实验结果一致,因此,可以利用主成分聚类分析确定紫外辐照改性蜂胶/纳米SiO2复合膜的最佳处理时间。     

红外光谱分析蜂胶乙基纤维素微球中的溶剂残留

采用液中干燥法制备了蜂胶乙基纤维素微球。分析了主要组成原料的红外光谱图。结果证实,微球制备中出现的收率异常现象是因为溶剂液体石蜡残留所致。在选用的实验条件下,微球中不含乙醚、丙酮和Span-80。     

Preparation and Antimicrobial Activityof Gelatin Microparticles Containing Propolis Against Oral Pathogens

ABSTRACT

Gelatin microparticles containing propolis ethanolic extractive solution were prepared by spray-drying technique. Particles with regular morphology, mean diameter ranging of 2.27 μm to 2.48 μm, and good entrapment efficiency for propolis were obtained. The in vitro antimicrobial activity of microparticles was evaluated against microorganisms of oral importance (Enterococcus faecalis, Streptococcus salivarius, Streptococcus sanguinis, Streptococcus mitis, Streptococcus mutans, Streptococcus sobrinus, Candida albicans, and Lactobacillus casei). The utilized techniques were diffusion in agar and determination of minimum inhibitory concentration. The choice of the method to evaluate the antimicrobial activity of microparticles showed be very important. The microparticles displayed activity against all tested strains of similar way to the propolis, showing greater activity against the strains of E. salivarius, S. sanguinis, S. mitis, and C. albicans.     

Identification of Free Radical Scavengers from Brazilian Green Propolis Using Off‐Line HPLC‐DPPH Assay and LC‐MS

Brazilian green propolis is known as an appreciable natural antioxidant with abundant polyphenolic compounds. For quality control, a fingerprint‐efficacy study of Brazilian green propolis was carried out in this work. Chemical fingerprints of Brazilian green propolis from 22 different sources were determined by HPLC and investigated by similarity analysis. The fingerprint‐efficacy relationships between chemical fingerprint and DPPH radical‐scavenging activity were established. The results showed that 14 characteristic common peaks were identified, and 9 compounds were discovered with free radical‐scavenging activities. Caffeoylquinic acids and artepillin C might be the major effective components for quality control of Brazilian green propolis due to their specificity and strong antioxidant activity. This study provides new markers for the quality assessment of Brazilian green propolis and its derived products.     

中国东北黑蜂蜂胶醇提物化学性质的研究

为了考察东北黑蜂蜂胶乙醇提取物(Ethanol extracts from the Chinese northeast black bee propolis,EENBP)的理化性质,采用扫描电镜、紫外光谱、红外光谱、GC-MS和LC-MS等技术,分别研究了EENBP的化学组成和特征图谱。扫描电镜分析结果表明超声辅助提取制得的EENBP混合更加均匀;紫外和红外光谱分析结果表明EENBP中的的化学组分主要包括黄酮类、萜烯类、酯类、酚酸类和醇类等。GC-MS结果表明超声辅助提取制得的EENBP中挥发性成分主要是萜烯类化合物,分别是大根香叶烯、杜松烯、愈创木醇和芹子烯。LC-MS从超声辅助提取制得的EENBP中鉴定出苯甲醛、咖啡酸、香豆酸和阿魏酸,蜂胶中还含有柯因、异鼠李素和山奈素等成分。上述结果说明超声辅助提取制得的EENBP活性成分丰富,可以进一步进行相应功能的健康食品、药品的开发。     

蜂胶中微量元素的测定--离子色谱法

介绍了用离子色谱法测定蜂胶中的微量元素。此方法具有操作简便、快速、灵敏度高、选择性好和能同时测定多种组分的特点。应用离子色谱仪测定了蜂胶中的铜、锌、镁、钙、钠、钾、铁、铝等多种微量元素 ,结果表明蜂胶中含有多种人体所需的微量元素。     

The effect of chitosan coating incorporated with ethanolic extract of propolis on the quality of refrigerated chicken fillet

Chitosan is considered as a functional packaging component for maintaining the quality and increasing the shelf life of perishable foods include meat, poultry, fish, dairy products, and all cooked leftovers. The present study was conducted to evaluate edible coating of chitosan (2%) containing ethanolic extract of propolis (1% and 2%) on microbiological (mesophilic aerobic, psychrotrophic, lactic acid bacteria, coliforms, and Staphylococcus aureus counts), chemical (TBARS, TVN and Peroxide values) and sensory (odor, color, texture, taste, and overall acceptance) properties of chicken fillet. Microbial analysis showed that coating had a significant reducing effect on growth of bacteria during 12 days at 4 °C. Besides, the increase of TBARS, Total volatile nitrogen, and peroxide value of samples coated by chitosan and ethanolic extract of propolis was less than control group. According to our results, chitosan and propolis can be used to enhance the shelf life of fillet and maintain its quality.

Practical applications

Propolis is used for infections caused by bacteria, viruses, fungus, and by single‐celled organisms called protozoans. Propolis is also used as an antioxidant and anti‐inflammatory agent. Ethanol extract of propolis improve the properties of chitosan edible coating in chicken fillet preservation. The chitosan coating incorporated with ethanolic extract of propolis can improve the microbial, chemical, and sensory quality of food and enhance the shelf life of them by synergistic effects.