发酵对西兰花硫代葡萄糖苷缓解秀丽隐杆线虫氧化损伤的影响

为探讨乳酸菌发酵对西兰花硫代葡萄糖苷（简称硫苷）抗氧化能力的影响，本研究以植物乳杆菌发酵西兰花，测定硫苷的代谢产物组分和体外抗氧化能力。同时，考察发酵硫苷对秀丽隐杆线虫抗应激能力和抗氧化指标的影响。结果表明，乳酸菌发酵增强了西兰花硫苷体外抗氧化能力。线虫实验显示发酵硫苷能够提高秀丽隐杆线虫在热应激和氧化应激下的存活率，显著降低线虫体内活性氧和脂褐素水平（P<0.05），提高超氧化物歧化酶活力，从而缓解线虫氧化损伤。通过乳酸菌发酵可以提高西兰花硫苷的抗氧化活性，为西兰花等十字花科蔬菜中硫苷的开发利用提供理论支撑。     

热烫对4种芸薹属蔬菜硫代葡萄糖苷及其吲哚族降解产物的影响

研究了热烫对甘蓝、娃娃菜、小白菜和瓢儿菜4种芸薹属蔬菜硫苷及其吲哚族硫苷降解产物的影响。结果表明,4种蔬菜硫苷含量明显不同,鲜甘蓝中总硫苷含量最高(89.73μmol/g干重),鲜瓢儿菜总硫苷含量最低(34.94μmol/g干重)。新鲜蔬菜在90℃下分别用水热烫处理20、40、60 s后,各蔬菜的硫苷含量均显著降低,热烫60 s,总硫苷物质损失71%~73%。新鲜蔬菜总吲哚族硫苷降解产物含量相近,90℃热烫20~60 s能显著提高其吲哚族硫苷降解产物含量。结果表明,热烫60 s能使4种芸薹属蔬菜的吲哚族硫苷降解产物含量增加1~5倍,有利于提高其抗肿瘤、抑菌等生理活性,可作为蔬菜烹饪预处理的手段之一。     

西兰花中硫代葡萄糖苷的研究进展

硫代葡萄糖苷(简称硫苷)是西兰花中一类重要次生代谢产物,其在内源黑芥子酶的作用下水解生成多种活性物质。硫苷及其降解物具有抗癌、抗氧化、抗菌等多种活性功能,已引起研究者们广泛关注。该文概述了硫代葡萄糖苷的结构性质、合成降解途径,综述了硫苷的分离检测技术和生理功能等相关研究进展,为硫苷类物质的合理开发与利用提供参考。     

红色LED光照下上海青采后硫代葡萄糖苷代谢的变化

为研究发光二极管（Light-Emitting Diodes，LED）处理对上海青采后硫代葡萄糖苷（简称硫苷）代谢的作用机理，该研究首先采用不同颜色和光密度的光照处理上海青，得出6.5 μmol/(m2•s)的红色LED光照处理可显著抑制上海青中叶绿素降解，延缓其黄化。在此基础上，研究了6.5 μmol/(m2•s)红色LED光照处理对贮藏期间上海青中硫苷代谢相关物质及基因表达水平的影响。结果表明，上海青叶柄中总硫苷和异硫氰酸酯含量分别为叶片的2.72倍和1.32倍；红色LED光照处理可显著上调上海青叶柄中脂肪族合成关键基因MYB28、CYP83A1、GSTF11等的表达水平，从而促进叶柄中主要硫苷物质3-丁烯基硫苷等的合成；由此，上海青叶柄中总硫苷含量在贮藏4~8 d期间为对照组的1.62~1.99倍；同时，该处理提升了上海青叶柄的黑芥子酶活性，从而促进了总异硫氰酸酯的积累，且在贮藏4~8 d期间，对照组上海青叶柄的总异硫氰酸酯含量为红光处理组的77.43%~91.98%。综上，红色LED光照处理通过调控硫苷合成关键基因和黑芥子酶活性来延缓上海青中硫苷物质和异硫氰酸酯的流失。     

硫代葡萄糖苷对肿瘤细胞的增殖抑制作用

硫代葡萄糖苷(硫苷)是广泛存在于十字花科蔬菜中的次级代谢产物,具有丰富的生物活性。硫苷存在于十字花科蔬菜的根、茎、叶和种子中,但主要存在于种子中。近年来的流行病学研究发现,食用十字花科蔬菜能降低多种癌症的患病危险。本文以十字花科蔬菜芥菜属白芥子中的硫代葡萄糖苷为研究对象,采用MTT法研究了不同浓度的硫苷提取物不同时间作用下对肿瘤细胞的增殖抑制作用。结果表明,硫苷提取物对SGC-7901、HepG2、NCI-H446细胞都具有显著的抑制作用,说明该提取物具有普遍的抗肿瘤作用。     

红枣汁发酵过程中主要功效酶活性及相关代谢产物变化规律的研究

以酵母菌和植物乳杆菌复合发酵枣汁为研究对象,以蛋白酶活性、脂肪酶活性、SOD活性、总酚、总糖、总酸和蛋白质为研究指标来探讨枣汁在发酵过程中主要功效酶活性、代谢产物的变化规律。结果表明,发酵过程中3种主要功效酶活性有显著差异(P0.05),而发酵后枣液中的代谢产物总酸含量变化也有显著差异(P0.05),在发酵第7天时两者差值最大,发酵7 d后比未发酵时增加了6.45倍。发酵后总酚含量整体比发酵前有所提高,蛋白质含量呈先下降后上升趋势,总糖含量呈显著下降后平稳又上升趋势。结果表明,研究结果可以为后期发酵枣汁的发酵机制和工艺以及综合产品的开发提供一定的技术参考。     

黑木耳发酵产物对HepG2细胞脂质代谢及糖代谢的影响

目的:通过建立体外HepG2细胞脂肪累积模型及正常HepG2细胞模型评价不同分子质量黑木耳发酵产物对HepG2细胞脂质代谢及糖代谢的影响,揭示不同分子质量黑木耳发酵产物对细胞脂质代谢及糖代谢的调节作用及差异。方法:采用超滤法将黑木耳发酵上清液分为0~10,10~50,50~100,100~300 ku,以及>300 ku的分子质量,并通过恒温干燥获得黑木耳发酵产物。通过HepG2细胞脂肪累积模型及正常HepG2细胞模型,以噻唑兰染色吸光度(MTT值)、油红O染色、甘油三酯(TG)值、总胆固醇(TC)值、脂蛋白脂酶(LPL)、肝脂酶(HL)活性、葡萄糖含量、肝糖原含量、己糖激酶(HK)活性评价不同分子质量黑木耳发酵产物对HepG2细胞脂质代谢及糖代谢的影响。结果:黑木耳发酵产物能够调节HepG2细胞脂质代谢及糖代谢,降低细胞脂肪积累及葡萄糖含量,提升脂肪代谢酶与糖代谢酶的活性。其中100~300 ku与>300 ku的黑木耳发酵产物作用效果更明显。结论:黑木耳发酵产物能够调节HepG2细胞脂质代谢及糖代谢,且100~300 ku与>300 ku黑木耳发酵产物作用效果更明显。     

酿酒酵母与非酿酒酵母混合发酵 对果酒品质的影响

果酒以其酒精含量低、营养物质丰富、口感风味独特等优良特性越来越受到消费者欢迎。然而发酵过程中酵母菌种类的选择直接影响到果酒的品质。由于非酿酒酵母在发酵过程中能够产生丰富的代谢产物,对增强果酒的营养价值和风味具有积极作用,因此多菌种混合发酵受到越来越广泛的关注。本文综述了混合发酵过程中非酿酒酵母的作用、酿酒酵母和非酿酒酵母之间的相互作用(包括酵母菌细胞之间的相互作用和代谢产物对酵母菌的影响)以及混合发酵对果酒风味、抗氧化活性、色素等品质的影响,为非酿酒酵母在果酒发酵中的应用提供参考。     

硫甙葡萄糖苷降解研究进展

通过硫苷生物合成、降解途径、降解产物分析方法和降解产物功能作用对十字花科植物中次级代谢产物硫甙葡萄糖苷降解情况进行综述。硫苷生物合成以氨基酸为底物经过3 个步骤完成;硫苷降解存在酶降解、热降解、化学降解;硫苷降解产物分析方法主要采用化学分析和色谱分析;硫苷降解产物既有抗癌的积极作用又有抗营养化的消极作用。     

4种水产副产品纳豆菌发酵产物的生物活性比较

为实现水产副产物的高效利用，从中获得更有价值的生物活性组分，以鲍鱼生殖腺、扇贝裙边、罗非鱼皮和海参卵这些副产物为原料，以纳豆菌发酵传统底物黄豆粉为对照原料，接种纳豆菌进行液体发酵。测定发酵产物的纤溶酶活性、可溶性蛋白含量(SPC)、三氯乙酸可溶性寡肽(TCASOP)、抗凝血活性、血管紧张素转换酶(ACE)抑制活性等，以确定上述副产品是否适于通过纳豆菌发酵制备功能性产品。结果显示，罗非鱼皮和黄豆粉纤溶酶峰值活性相当且最高，达到5 760 FU/mL。纳豆菌能够不同程度地将5种原料中的蛋白质转化成SPC，其中SPC含量上升幅度最大且较稳定的是海参卵发酵产物，峰值达到8.63 mg/mL。上述原料在0 h的TCASOP含量均低于1 mg/mL，但各发酵产物中TCASOP峰值含量升至4.69~7.87 mg/mL，其中罗非鱼皮最高。鲍鱼生殖腺在0 h就呈现极强的抗凝活性，显著延长TT、PT、ATPP，甚至远超过1 μg/mL肝素钠对照，但发酵过程中活性明显下降；海参卵和罗非鱼皮发酵产物均呈现一定抗凝活性。发酵36~60 h内，5种发酵产物均具有ACE抑制活性，豆粉发酵产物的活性始终保持最高，但扇贝裙边发酵产物的活性在36 h后与豆粉相当，且最高抑制率可达到94.66%。上述研究表明4种水产副产品及其纳豆菌发酵产物在溶栓、抗凝和ACE抑制方面各具特点，在相关功能食品方面具有一定开发潜力。     

海藻乳酸菌发酵的研究进展

海藻是一类重要的海洋资源,富含大量营养元素如蛋白质、碳水化合物、维生素和矿物质,以及多糖、酚类等生物活性物质。由于海藻营养价值极高,利用乳酸菌发酵海藻促进生物活性化合物的产生和释放,具有良好的健康效益。因此,本文根据国内外近年来利用乳酸菌发酵海藻的相关研究报道,对乳酸菌发酵类型、乳酸菌发酵海藻的可行性和乳酸菌主要种类、以及乳酸菌在海藻发酵中的效果和作用进行阐述,同时综述了乳酸菌发酵海藻在食品行业中的开发应用现状,并对今后发展趋势和前景进行展望,为藻类乳酸菌发酵制品的开发提供一定参考。     

Modelling the fate of glucosinolates during thermal processing of Brassica vegetables

Glucosinolates are secondary metabolites of Brassica vegetables that have been associated with health benefits. The concentrations of these compounds are strongly affected by processing of the vegetables. Various mechanisms are responsible for these changes: Lysis of plant cells and compartments, diffusion and leaching of glucosinolates and myrosinase (a plant enzyme able to hydrolyze glucosinolates) into the cooking water, enzymatic hydrolysis of glucosinolates, inactivation of myrosinase and thermal degradation of glucosinolates. This publication presents a dynamic mathematical model that includes these mechanisms with their estimated parameters and the effect of temperature on them.Simulations made by the model for several process conditions show losses of glucosinolates as a consequence of domestic boiling of 69%, microwaving of 8%, industrial blanching of 37% and by industrial sterilization of 82%.The model can assist in adapting the processing conditions like the time–temperature profile and the vegetable–water ratio to optimize industrial and domestic processing of Brassica vegetables in terms of health benefits. In addition this model can help to add the effect of vegetable preparation practices on the quantitative glucosinolate intake in epidemiological studies.     

A Mechanistic Perspective on Process-Induced Changes in Glucosinolate Content in Brassica Vegetables: A Review

Brassica vegetables are consumed mostly after processing, which is expected to give beneficial effects on the vegetable properties, such as improved palatability and bioavailability of nutrients, or shelf life extension. But processing also results to various changes in the content of health promoting phytochemicals like glucosinolates. This paper reviews the effects of processing on the glucosinolates content by using a mechanism approach underlying processing method employed. Cultural differences between Eastern and Western preparation practices and their possible effect on glucosinolate retention are highlighted. Boiling and blanching considerably reduce the glucosinolate content mainly due to mechanisms of cell lysis, diffusion, and leaching, and partly due to thermal and enzymatic degradation. Steaming, microwave processing, and stir frying either retain or slightly reduce the glucosinolates content due to low degrees of leaching; moreover, these methods seem to enhance extractability of glucosinolates from the plant tissue. Fermentation reduces the glucosinolate content considerably, but the underlying mechanisms are not yet studied in detail. Studying the changes of glucosinolates during processing by a mechanistic approach is shown to be valuable to understand the impact of processing and to optimize processing conditions for health benefits of these compounds.     

Health benefits of fermented foods

In the past, the beneficial effects of fermented foods on health were unknown, and so people primarily used fermentation to preserve foods, enhance shelf life, and improve flavour. Fermented foods became an important part of the diet in many cultures, and over time fermentation has been associated with many health benefits. Because of this, the fermentation process and the resulting fermented products have recently attracted scientific interest. In addition, microorganisms contributing to the fermentation process have recently been associated with many health benefits, and so these microorganisms have become another focus of attention. Lactic acid bacteria (LAB) have been some of the most studied microorganisms. During fermentation, these bacteria synthesize vitamins and minerals, produce biologically active peptides with enzymes such as proteinase and peptidase, and remove some non-nutrients. Compounds known as biologically active peptides, which are produced by the bacteria responsible for fermentation, are also well known for their health benefits. Among these peptides, conjugated linoleic acids (CLA) have a blood pressure lowering effect, exopolysaccharides exhibit prebiotic properties, bacteriocins show anti-microbial effects, sphingolipids have anti-carcinogenic and anti-microbial properties, and bioactive peptides exhibit anti-oxidant, anti-microbial, opioid antagonist, anti-allergenic, and blood pressure lowering effects. As a result, fermented foods provide many health benefits such as anti-oxidant, anti-microbial, anti-fungal, anti-inflammatory, anti-diabetic and anti-atherosclerotic activity. However, some studies have shown no relationship between fermented foods and health benefits. Therefore, this paper aims to investigate the health effects of fermented foods.     

Predictive modelling of health aspects in the food production chain: a case study on glucosinolates in cabbage

In this paper, it is demonstrated that many steps in the food production chain of vegetable products can have large influence on the final intake of health protective phytochemicals. The wide variations in levels at each step in the production chain makes an experimental quantification of the dietary intake of phytochemical extremely difficult. We present a concept for predictive modelling of the effects of various processes in the production chain of vegetable products on the intake of phytochemicals with potential health benefits. This approach is intended to be used for the developments of tools to facilitate both product and process development for health products as well as epidemiological input data for bioactive substances in the diet. Protective glucosinolates present in Brassica vegetables are used to illustrate the value of such a predictive model. The described model provides a powerful tool for handling the variation of glucosinolate levels throughout the chain in a quantitative way. Product development, consumer advice and human intervention trials are important areas that could benefit enormously from this approach.     

Production of Bioactive Peptides from Lactic Acid Bacteria: A Sustainable Approach for Healthier Foods

Traditional fermented foods where lactic acid bacteria (LAB) are present have been associated with beneficial effects on human health, and some of those benefits are related to protein‐derived products. Peptides produced by LAB have attracted the interest of food industries because of their diverse applications. These peptides include ribosomally produced (bacteriocins) and protein hydrolysates by‐products (bioactive peptides), which can participate as natural preservatives and nutraceuticals, respectively. It is essential to understand the biochemical pathways and the effect of growth conditions for the production of bioactive peptides and bacteriocins by LAB, in order to suggest strategies for optimization. LAB is an important food‐grade expression system that can be used in the simultaneous production of peptide‐based products for the food, animal, cosmetic, and pharmaceutical industries. This review describes the multifunctional proteinaceous compounds generated by LAB metabolism and discusses a strategy to use a single‐step production process, using an alternative protein‐based media. This strategy will provide economic advantages in fermentation processes and will also provide an environmental alternative to industrial waste valorization. New technologies that can be used to improve production and bioactivity of LAB‐derived peptides are also analyzed.     

传统发酵蔬菜制作工艺、品质特征及影响因素研究概况

传统发酵蔬菜是全世界最具代表性的发酵食品之一,因其独特的风味、丰富的益生菌和生物活性物质,广受人们喜欢。在中国,传统的自然发酵方式仍是发酵蔬菜的主要生产方式,尚未形成大规模的工业化生产。另外,传统发酵蔬菜的发酵机理尚未阐明。因此,该文总结了传统发酵蔬菜的制作工艺、从理化指标及微生物两个指标归纳了传统发酵蔬菜的品质特征、概述了传统发酵蔬菜在发酵过程中的底物和发酵产物、阐述了发酵过程的微生物及其作用,从以上几个角度综述了传统发酵蔬菜的研究现状及进展,并对传统发酵蔬菜的发展前景进行展望,以期为阐明传统发酵蔬菜中微生物的作用机制提供更多思路,为实现其发酵过程的精准化调控奠定理论基础。     

Influence of pressure/temperature treatments on glucosinolate conversion in broccoli (Brassica oleraceae L. cv Italica) heads

Glucosinolates are a group of secondary plant metabolites that are found in the Brassicaceae family. Upon hydrolysis by the endogenous enzyme myrosinase, a large number of compounds can be formed of which some are potentially anticarcinogenic, while others are largely inactive. Furthermore, some bioactive compounds are unstable. Therefore, it is not only important to determine the type and amount of glucosinolates present or hydrolysed in a given plant, but it is also relevant to investigate the type of hydrolysis products. In this research, the effect of combined pressure–temperature treatments (100–500 MPa, 20–40 °C) on the glucosinolate conversion and the kind of hydrolysis products was studied in broccoli, both during treatment and after autolysis. The results, showed that high pressure can induce glucosinolate hydrolysis during treatment, promote the formation of isothiocyanates after treatment and that relatively more indole oligomers are formed during treatment than during autolysis. These results indicate that pressure treatment limits the loss of glucosinolates and its health beneficial products.     

Lactic acid bacteria from fermented table olives

Table olives are one of the main fermented vegetables in the world. Olives can be processed as treated or natural. Both have to be fermented but treated green olives have to undergo an alkaline treatment before they are placed in brine to start their fermentation. It has been generally established that lactic acid bacteria (LAB) are responsible for the fermentation of treated olives. However, LAB and yeasts compete for the fermentation of natural olives. Yeasts play a minor role in some cases, contributing to the flavour and aroma of table olives and in LAB development.