毛蚶抗菌活性筛选及低极性组分GCMS分析

目的:研究毛蚶的抗菌活性部位及有效成分。方法:毛蚶软组织经乙醇提取后,采用液液萃取法将提取物分为石油醚相、乙酸乙酯相、正丁醇相和水相4个不同的极性部位;采用抑菌圈法和最小杀菌浓度测定法,对毛蚶乙醇提取物和各极性部位进行了抗菌活性测定,并用正相硅胶柱对抗菌活性较好的石油醚相进行了分离纯化,得到甾体组分;采用GC-MS技术对石油醚相和甾体组分进行了化学成分分析。结果:毛蚶石油醚相的抑菌效果最好;从毛蚶石油醚相中鉴定出了30个化合物,主要为脂肪类和甾醇类化合物;从甾体组分中鉴定出8个化合物,其中7个为首次从毛蚶中分离鉴定。结论:毛蚶的石油醚相具有明显的抗菌活性,石油醚相以甾醇类化合物为主。     

一种亚麻籽甾醇的结构鉴定及抗氧化活性研究

采用硅胶柱层析分离,通过化学和波谱分析方法鉴定化合物的结构。选择亚油酸过氧化体系、邻菲罗啉化学发光体系、邻苯三酚体系,对化合物进行了抗氧化活性实验。结果表明：单体是一种首次发现的甾醇类化合物,该化合物结构是：24-乙基-胆甾烷-3-氧-β-D-葡萄糖苷,具有较强的抗亚油酸氧化能力,但清除羟基自由基和超氧阴离子自由基能力弱。     

荸荠皮活性成分提取分离研究进展

荸荠中活性物质丰富,具有抑菌、消炎、降压、抗癌等良好的药用价值。荸荠的活性物质主要集中在荸荠皮,目前荸荠皮活性成分的提取分离研究主要集中在黄酮类、多酚类、甾醇类、糖类等化合物。综述国内外荸荠皮中的黄酮类、多酚类、甾醇类、糖类等活性成分的提取分离研究现状,并展望了荸荠皮活性成分在提取分离的研究方向及应用趋势,期望为系统地开展荸荠皮活性成分提取分离研究、进一步扩大荸荠皮活性成分的开发利用提供有益参考。     

植物油不皂化物的色谱分离

植物油不皂化物是多种有机化合物的混合物，其主要成分为烃类、三萜醇类、４－甲基甾醇类和甾醇类。采用柱色谱、薄层色谱、高效液相色谱和离心薄层色谱四种不同的色谱法，将以上四类化合物分离并纯化，测得各类化合物在不皂化物中的含量。对四种色谱分离不皂化物的方法进行了比较与讨论。     

红黑二丸中甾醇类物质的抑菌活性

采用牛津杯法和菌饼法分别测定红黑二丸甾醇类物质对细菌和霉菌的抑菌活性,并测定其最低抑菌浓度(MIC)。结果表明：红黑二丸甾醇类物质对金黄色葡萄球菌、枯草芽孢杆菌、大肠杆菌、沙门氏菌、志贺氏菌、黑曲霉和橘青霉均有一定的抑制效果,当甾醇质量浓度为7.0mg/mL时,对金黄色葡萄球菌的抑制效果最好,其抑菌直径大于9mm。红黑二丸甾醇类物质对金黄色葡萄球菌的抑制作用最强,其MIC值为0.5mg/mL。不同质量浓度红黑二丸甾醇类物质对细菌的药效持久性随着时间的延长呈下降趋势,且质量浓度越高,抑菌作用越明显。     

新型功能性食品添加剂——植物甾醇类

植物甾醇,包括甾烷醇及其酯的形式,是一类具有降低血清胆固醇作用的功能因子。本文介绍了它的分类、物化性质、生理活性、产品开发方面的概况。     

造纸法再造烟叶加工过程中5种甾醇的含量变化

为研究造纸法再造烟叶各工艺阶段甾醇类化合物的含量变化,利用超高效液相色谱-串联质谱仪(UPLC-MS/MS)对5种甾醇(麦角甾醇、胆甾醇、菜油甾醇、豆甾醇及β-谷甾醇)进行了测定。结果表明:①烟叶原料中5种甾醇的含量(质量分数)均高于烟梗,且两种烟草原料中的甾醇类化合物均以豆甾醇和β-谷甾醇为主;②在提取和浓缩阶段,甾醇含量均降低,降低量分别占原料中甾醇总量的21.35%和15.13%;③在掺配阶段,低浓浆中甾醇实际增加量占原料中甾醇总量的10.64%;④在打浆和抄造阶段,甾醇含量均降低,降低量分别占原料中甾醇总量的14.06%和14.18%;⑤其余工艺阶段的甾醇含量变化不大,最终再造烟叶产品中甾醇量占原料中甾醇总量的48.67%。      

食用菌中甾醇物质抗炎活性研究概述

近年来,在天然产物中筛选具有抗炎作用药物的研究愈加深入。食用菌分布广泛,次级代谢产物丰富,在许多方面表现出良好的生理活性,从而引起了普遍的关注。文章对食用菌中具有抗炎活性的甾醇类物质的提取、测定、分离纯化及其抗炎作用的研究方法和作用机制进行了整理,以期为以后的相关研究提供参考。     

西沙诺尼果汁提取物对肿廇细胞增殖的抑制作用

以我国海南西沙诺尼果汁为原料,经分离提取,得到以多糖、氨基酸、黄酮类和甾醇类物质为主要成分的6种组分。通过MTT方法比较不同组分对人肺癌细胞A549、乳腺癌细胞MCF-7、肝癌细胞HepG2、结肠癌细胞HCT116和宫颈癌细胞HeLa增殖的抑制作用。试验结果表明:诺尼果汁中的黄酮类组分和甾醇类组分能抑制肿廇细胞增殖,并呈剂量依赖性。其中5号甾醇类组分抗肿瘤活性最强,对HCT116和HeLa细胞IC50分别为20.9和22.1μg/mL,说明诺尼果汁具有辅助治疗癌症的潜力。     

植物甾醇深加工产品的研究进展

植物甾醇是一种天然活性物质,具有多种生理功能。植物甾醇的双键被饱和后称为甾烷醇。酯化后称为甾烷醇酯。近年来研究发现植物甾烷醇及甾烷醇酯的稳定性、表面活性等理化性质较之植物甾醇明显改善,从而拓展了植物甾醇的应用领域。本文依据当前国内外文献及专利,介绍了植物甾醇深加工产品的结构性质、应用方向及制备方法等,并展望了其研究发展前景。     

鹰嘴豆功能活性及应用研究进展

鹰嘴豆是一种常见的豆类植物,在自然界中广泛存在,富含多种优质蛋白、脂肪、氨基酸、维生素、膳食纤维以及钙、镁、铁、锌、磷等多种微量元素,营养价值高且具有多种功能活性。目前从鹰嘴豆中提取分离出来的生物活性物质就有20多种,这类物质主要有多糖、皂苷、异黄酮、多肽、甾醇、酚类、有机酸等。研究发现,鹰嘴豆活性成分具有抗氧化、免疫、降血糖、降血脂、降低胆固醇、抗癌等多种生理功效,且因其天然无毒副作用,因此有加工成具有食用和药用价值保健产品的潜力,具有广阔的发展前景。本文综述了近年来国内外关于多糖、皂苷、黄酮、多肽等多种鹰嘴豆生物活性物质及鹰嘴豆应用方面的研究进展,通过本文综述,以期推进鹰嘴豆高值化利用,促进鹰嘴豆深加工产业发展,进一步为功能食品开发和农产品深加工提供理论依据。     

桑叶的化学成分、生理功能及应用研究进展

桑叶是我国的传统中药之一,含有多种功能性成分,如矿物质、维生素、食物纤维、氨基酸、植物甾醇、黄酮类、生物碱类、多糖等,具有降血糖、降血压、降低胆固醇、抗衰老、维持消化系统和排泄系统健康、防癌抗癌、提高免疫力等多种生理功能。本文综述了近年来国内外对桑叶的化学成分及其生理功能的研究进展以及桑叶保健制品的开发利用情况,为桑叶资源的合理开发利用提供了依据。     

Bioactive Natural Constituents from Food Sources—Potential Use in Hypertension Prevention and Treatment

Prevention and management of hypertension are the major public health challenges worldwide. Uncontrolled high blood pressure may lead to a shortened life expectancy and a higher morbidity due to a high risk of cardiovascular complications such as coronary heart disease (which leads to heart attack) and stroke, congestive heart failure, heart rhythm irregularities, and kidney failure etc. In recent years, it has been recognized that many dietary constituents may contribute to human cardiovascular health. There has been an increased focus on identifying these natural components of foods, describing their physiological activities and mechanisms of actions. Grain, vegetables, fruits, milk, cheese, meat, chicken, egg, fish, soybean, tea, wine, mushrooms, and lactic acid bacteria are various food sources with potential antihypertensive effects. Their main bioactive constituents include angiotensin I-converting enzyme (ACE) inhibitory peptides, vitamins C and E, flavonoids, flavanols, cathecins, anthocyanins, phenolic acids, polyphenols, tannins, resveratrol, polysaccharides, fiber, saponin, sterols, as well as K, Ca, and P. They may reduce blood pressure by different mechanisms, such as ACE inhibition effect, antioxidant, vasodilatory, opiate-like, Ca²⁺ channel blocking, and chymase inhibitory activities. These functional foods may provide new therapeutic applications for hypertension prevention and treatment, and contribute to a healthy cardiovascular population. The present review summarizes the antihypertensive food sources and their bioactive constituents, as well as physiological mechanisms of dietary products, especially focusing on ACE inhibitory activity.     

大豆皂苷结构及生理活性研究进展

大豆皂苷大量存在于大豆的胚芽、胚轴等部分,尤其是在脱脂豆粕中含量丰富,可以作为一类高附加值的产品进行生产,提高大豆油加工副产物的利用率。大豆皂苷属于五环三萜类化合物,是一种齐墩果烷型皂苷,由疏水性苷元和亲水性糖基组成,具有一定的两亲性,并具有抗肿瘤、抗炎、抗氧化、调节免疫力、保护肝脏等多种生理活性。近年来,大豆皂苷的研究领域从活性验证到分子机制不断拓展,产出了一批具有前瞻性的研究成果。不同结构与类型的大豆皂苷表现出的生理活性及作用机制不同,相关研究为大豆皂苷在食品和医药等领域的应用提供了理论基础。重点阐述了大豆皂苷的结构与分类、生理活性及构效关系的最新研究进展,分析了加工方式对大豆皂苷结构的影响,总结了大豆皂苷发挥生理活性的机制及其基于生理活性的应用,剖析了大豆皂苷在未来应用中亟待解决的问题,以期为大豆皂苷进一步研究和开发利用提供理论依据。     

Arbutus species (Ericaceae) as source of valuable bioactive products

Abstract

In addition to nutrients, plant foods contain compounds that may provide additional health benefits improving the quality of life. Species from Arbutus genus (Ericaceae) represent a promising source of healthy phytochemicals. Bioactive compounds including such as anthocyanins, iridoids, phenols, triterpenes, sterols, and fatty acids are reported from Arbutus species. Some Arbutus species revealed promising biological activities including antioxidant, anti-inflammatory, anti-proliferative, anti-diabetic, and antimicrobial activities, and deserve for that reason further consideration for new drug discovery. However, only few species are investigated scientifically for their chemical profile and biological activities. The aim of this article is to summarize the current knowledge of the components and biological properties of Arbutus species common in Mediterranean area, as well as the future prospects on their applications as potentially valuable products.     

生物碱应用的研究进展

生物碱是存在于植物体内的一类重要碱性含氮物质,具有良好的生理活性,综述了近年来生物碱在饲料、药物、食品、保健品等领域应用的研究进展,重点讨论了生物碱应用的研究热点及存在的问题,展望了生物碱的发展前景。     

金樱子多糖提取、纯化及生理活性研究进展

金樱子为蔷薇科蔷薇属植物,多糖为其重要成分,具有抗氧化、降血脂等多种生理活性。现阶段金樱子多糖提取方法较多,却少有归纳总结,而分离纯化方法的创新研究较少。此外,多项研究已经表明金樱子多糖具有良好的生理活性,但相关作用机制研究不足。本文主要阐述了金樱子多糖提取、分离纯化方法及生理活性的研究进展,并对其研究现状进行讨论和展望。     

Strategies for designing novel functional meat products

In recent years, much attention has been paid to physiological functions of foods due to increasing concerns for health. Although there has been limited information of physiological functions of meat until recently, several attractive meat-based bioactive compounds, such as carnosine, anserine, l-carnitine, conjugated linoleic acid, have been studied. Emphasizing these activities is one possible approach for improving the health image of meat and developing functional meat products. This article provides potential benefits of representative meat-based bioactive compounds on human health and an overview of meat-based functional products. Strategies for designing novel functional meat products utilizing bioactive peptides and/or probiotic bacteria, is also discussed. This article focuses particularly on the possibility of meat protein-derived bioactive peptides, such as antihypertensive peptides. There are still some hurdles in developing and marketing novel functional meat products since such products are unconventional and consumers in many countries recognize meat and meat products to be bad for health. Along with accumulation of scientific data, there is an urgent need to inform consumers of the exact functional value of meat and meat products including novel functional foods.     

Marine Bioactive Compounds and Their Health Benefits: A Review

The significance of marine creatures as a source of unique bioactive compounds is expanding. Marine organisms constitue nearly half of the wordwide biodiversity; thus, oceans and sea present a vast resource for new substances and it is considered the largest remaining reservoir of beneficial natural molecules that maight be used as functional constituents in the food sector. This review is an update to the information about recent functional seafood compounds (proteins, peptides, amino acids, fatty acids, sterols, polysaccharides, oligosaccharides, phenolic compounds, photosynthetic pigments, vitamins, and minerals) focusing on their potential use and health benefits.     

Assessment of the reproductive-endocrine disrupting potential of chlorine dioxide oxidation products of plant sterols

This study examined the hypothesis that chlorine dioxide bleaching used in pulp and paper production causes the formation of reproductive-endocrine disrupting compounds from plant sterols. This was tested by conducting a laboratory simulation of the chlorine dioxide oxidation of two plant sterols, beta-sitosterol and stigmasterol. Oxidation products of the plant sterol beta-sitosterol were purified and identified and found to be cholestan-24-ethyl-3-one, 4-cholestene-24-ethyl-3-one, and 4-cholestene-24-ethyl-3,6-dione. The first two compounds were found in a number of pulp and paper effluents and biosolids. The sterols and their oxidation products were tested in vitro using bioassays for androgenicity and estrogenicity. A 28 d in vivo bioassay was employed to examine masculinization in female mosquitofish. In vitro bioassays revealed little estrogenic activity in the parent sterols or in mixtures of their oxidation products. Androgenic activity as measured by the androgen receptor binding bioassay was in the order of 19-96 microg/g testosterone equivalents but with no increase or decrease with chlorine dioxide oxidation. The mosquitofish bioassay did not show significant masculinization for any of the preparations tested. A number of androstane steroids were identified in the sterols tested, however, those compounds could only account for a small fraction of the androgenic activity in the sterols. It was clear that the parent sterols were not themselves acting as androgens in the bioassays used. This study indicated that chlorine dioxide oxidation of sterols produced predominantly oxidized sterols that were not likely to act through androgenic or estrogenic mechanisms.