Characterization and bioactivities of the exopolysaccharide from a probiotic strain of Lactobacillus plantarum WLPL04

Exopolysaccharide (EPS) was extracted and purified from Lactobacillus plantarum WLPL04, which has been confirmed previously as a potential probiotic for its antagonistic and immune-modulating activity. It has a molecular weight of 6.61 × 10⁴ Da, consisting of xylose, glucose, and galactose in an approximate molar ratio of 3.4:1.8:1. Microstructural studies demonstrated that the EPS appeared as a smooth sheet structure with many homogeneous rod-shaped lumps. The preliminary in vitro assays indicated that the EPS could significantly inhibit the adhesion of Escherichia coli O157:H7 to HT-29 cells in competition, replacement, and inhibition assays at a dose of 1.0 mg/mL, with an inhibition rate of 20.24 ± 2.23, 29.71 ± 1.21, and 30.57 ± 1.73%, respectively. Additionally, the EPS exhibited strong inhibition against biofilm formation by pathogenic bacteria, including Pseudomonas aeruginosa CMCC10104, E. coli O157:H7, Salmonella Typhimurium ATCC13311, and Staphylococcus aureus CMCC26003. Furthermore, the EPS showed good inhibitory activity against the proliferation of HT-29 cells. The characteristics and bioactivities of this EPS may make it a promising candidate in developing functional food.     

食用菌中萜类物质及其生物活性研究进展

近年来,自然资源因其在开发新的生物活性物质方面的巨大潜力而备受关注。食用菌分布广泛,营养物质丰富,具有抗炎、抗肿瘤、抑菌等多种药理作用。萜类物质来源广泛,种类繁多,是天然物质中最多的一类,大量研究表明食用菌中的萜类化合物具有多种生物活性,在医药行业具有重要的开发利用价值。本文主要对食用菌中萜类物质的抗炎、抗肿瘤、抗氧化及抑菌等生物活性进行综述,并对食用菌的开发利用进行展望。     

Camel milk protein hydrolysates with improved technofunctional properties and enhanced antioxidant potential in in vitro and in food model systems

Camel milk protein hydrolysates (CMPH) were generated using proteolytic enzymes, such as alcalase, bromelain, and papain, to explore the effect on the technofunctional properties and antioxidant potential under in vitro and in real food model systems. Characterization of the CMPH via degree of hydrolysis, sodium dodecyl sulfate-PAGE, and HPLC revealed that different proteins in camel milk underwent degradation at different degrees after enzymatic hydrolysis using 3 different enzymes for 2, 4, and 6 h, with papain displaying the highest degradation. Technofunctional properties, such as emulsifying activity index, surface hydrophobicity, and protein solubility, were higher in CMPH than unhydrolyzed camel milk proteins. However, the water and fat absorption capacity were lower in CMPH compared with unhydrolyzed camel milk proteins. Antioxidant properties as assessed by 2,2-azinobis(3-ethylbenzthiazoline-6-sulfonic acid) and 2,2-diphenyl-1-picrylhydrazyl radical scavenging activities and metal-chelating activity were enhanced after hydrolysis, in contrast to ferric-reducing antioxidant power which showed a decrease after hydrolysis. The CMPH were also tested in real food model systems for their potential to inhibit lipid peroxidation in fish mince and grape seed oil-in-water emulsion, and we found that papain-produced hydrolysate displayed higher inhibition than alcalase- and bromelain-produced hydrolysates. Therefore, the CMPH demonstrated effective antioxidant potential in vitro as well as in real food systems and showed enhanced functional properties, which guarantees their potential applications in functional foods. The present study is one of few reports available on CMPH being explored in vitro as well as in real food model systems.     

2,4-吡喃二酮衍生物的合成方法研究进展

2,4-吡喃二酮在医药和农药方面都是一个具有潜在生物活性的母体结构。其衍生物在医药方面具有抗菌、抗癌,抑制HIV朊酶等生物活性,在农药方面具有杀虫、杀菌、除草和抗植物病毒等。介绍了近年来2,4-吡喃二酮衍生物的合成方法的研究进展。     

杨梅素衍生物在农药创制中的研究进展

杨梅素衍生物作为一种重要的天然多羟基黄酮类化合物,具有抑菌、抗病毒、抗癌、消炎、抗氧化等较为广泛的药理活性,在医药和农药的创制中发挥着重要作用。综述了近年来杨梅素衍生物在农药创制方面的研究进展,主要介绍以杨梅素为先导化合物,通过活性拼接合成具有抑菌、抗病毒等生物活性的杨梅素衍生物活性小分子,以期望对研究工作者有一定的启发。     

4种印楝种子提取物对玉米象的生物活性

测定印楝4种不同提取物（印楝素A、印楝油、印楝乙酸乙酯粗提物和印楝超临界CO，提取物）对玉米象成虫的忌避、熏蒸和毒杀活性。4种提取物对玉米象成虫都具有较好的忌避活性，随着时间的推移，忌避活性呈下降趋势；4种提取物对玉米象成虫熏蒸活件差异较大，活性大小为印楝油〉超临界CO2提取物〉乙酸乙酯粗提物〉印楝素A。毒杀活件测定结果且示，4种提取物毒杀活性均较差，但由于印楝活件成分具有忌避、拒食和其它生物活性，对玉米象种群的数量有较明显的榨制作用。     

原花青素的生物活性研究

综述了近年来，植物中的提取物一原花青素在生物活性方面的研究：抗氧化、抗衰老作用；对心脏灌注损伤的保护作用；对肝脏细胞的保健作用；抗炎作用；抗肿瘤作用；抗诱变作用；DNA损伤的保护作用等，提示此类成分具有较高的生物活性及开发价值。     

云芝多糖生物活性及其提取纯化研究进展

云芝多糖是从云芝属真菌云芝中提取多糖类物质,由于其具有多种生物活性功能,已日益成为研究热点。该文综述云芝多糖的化学组成、生物活性及其提取纯化研究进展,并展望云芝多糖今后研究方向和发展前景。     

磷酸肌醇酯的生理活性及其研究进展

详细介绍了植酸的理化性质,对植酸和磷酸肌醇酯生理活性及其在医药行业的研究开发状况进行了综述。     

蕨菜化学成分及其生物活性研究进展

蕨菜作为药食两用植物,营养丰富,具有多种生物活性。文章总结了蕨菜化学成分及生物活性的相关研究,旨在为其进一步开发利用提供参考。