Characterization of in vitro anthocyanin-producing sour cherry (Prunus cerasus L.) callus cultures

Anthocyanin-producing callus cultures from in vitro sour cherry (Prunus cerasus L.) leaf tissues were established. As in the parent leaf tissues, the calli extracts showed the synthesis of a prevalent anthocyanin, cyanidin 3-glucoside. When the dark grown callus cultures were exposed to the light, cyanidin 3-glucoside content was increased from 0.1 to 4.5 mg 100 g⁻¹ fresh weight. Thus, of the available strategies for the enhancement of pigment production light resulted the triggering factor in this cell system. The addition of 50 μM jasmonic acid to the culture medium stimulated cyanidin 3-glucoside synthesis which resulted in an earlier appearance of pigment on the calli.     

Effects of methanolic extract of sour cherry (Prunus cerasus L.) on microbial growth

The antimicrobial activity of a methanolic extract of the common edible fruit Prunus cerasus L. was evaluated. HPLC analysis of the extract revealed the abundant presence of anthocyanins. Minimum Inhibitory Concentrations (MIC) for Gram‐positive and Gram‐negative pathogenic bacteria was in the range 2–6.6 mg mL^?1, whereas the time‐kill assay revealed that the bactericidal effect was exerted only at concentrations higher than 2× MIC. Interestingly, at concentrations lower than MIC, P. cerasus L. extract exerted a stimulating effect on bacterial proliferation and on the ability to form biofilms. In particular, a multidrug‐resistant Acinetobacter baumannii strain showed a 30% increase in growth at low concentrations. In the light of this finding, we speculate that the use of berry extracts (rich in anthocyanins) may present some risks to human health when used as preservatives in food and cosmetic products.     

Changes in sour cherry (Prunus cerasus L.) antioxidants during nectar processing and in vitro gastrointestinal digestion

Sour cherry (Prunus cerasus L.) is rich in polyphenols, and like its processed products, is especially rich in anthocyanins. We have applied HPLC, spectrophotometric and on-line antioxidant detection methods to follow the fate of cherry antioxidants during an entire multi-step industrial-scale processing strategy. This was performed for 22 sampling points, with five independent repeats from a commercial cherry nectar production process. Anthocyanins contributed to >50% of the total antioxidant capacity of the samples. An in vitro gastrointestinal (GI) digestion system was used to investigate serum availability of antioxidants. In this system anthocyanin bioavailability was much higher in the processed nectar than in the fresh fruit. Together these results indicate that processed sour cherry nectar is a rich source of stable antioxidants with high bioavailability, auguring well for the potential health-promoting capacity of sour cherry products.     

Isolation and identification of 5-carboxy-pyranoanthocyanins in beverages from cherry (Prunus cerasus L.)

Novel pyranoanthocyanins were identified by HPLC–ESI-MSⁿ in fermented and unfermented fruit juices from cherry (Prunus cerasus L.). The two major compounds, namely 5-carboxy-pyranocyanidin 3-O-(2^G-glucosylrutinoside) and 5-carboxy-pyranocyanidin 3-O-rutinoside were isolated by a combination of high-speed countercurrent chromatography with semi-preparative HPLC. Their structures were fully elucidated by means of NMR spectroscopy and mass spectrometry. As minor compounds 5-carboxy-pyranocyanidin 3-glucoside, 5-carboxy-pyranopeonidin-3-glucoside, and 5-carboxy-pyranopeonidin 3-rutinoside could be identified.These compounds are formed during storage of the juice through the reaction of pyruvic acid with the respective genuine anthocyanins.Industrial relevanceFor the consumers the color of fruit juices is one of the most important quality markers. However due to a fast degradation of anthocyanins, changes in color from purple/red hues to orange/brown hues can be observed during storage. The main objective of this study was the isolation, structural characterization and evaluation of pigments that are formed during aging of fruit juices. Pyranoanthocyanins were reported to possess a color stabilizing effect. In the present study it could be demonstrated that the color contribution of these newly formed pigments to the overall color of fruit juice was overestimated. Instead, the formation of polymeric pigments yields the highest impact (> 80%) on the color of aged fruit juices.     

不同干燥方法对膳食纤维提取率和性质的影响

分别采用热风65℃、热风105℃、微波干燥、微波热风(65℃)组合、微波热风(105℃)、红外微波组合和红外干燥等干燥方法对清洗的麸皮进行干燥。实验结果显示,各种干燥方法对IDF得率有一定影响,对IDF的持水力和膨胀力影响较大。微波干燥用时短,IDF得率为57%,微波干燥样品的持水力为710%,膨胀力为6mL/g,较热风干燥和远红外干燥好;热风干燥和远红外干燥方法制得的IDF的性质相差不大。     

高压均质和胶体磨改性对油橄榄果渣水不溶性膳食纤维性能的影响

采用高压均质和胶体磨改性处理油橄榄果渣水不溶性膳食纤维(IDF),比较改性前后IDF的微观形态、粒径分布、官能团组成及结晶结构,并测定分析其理化性质。结果表明:高压均质IDF的结构疏松,有较多的裂缝和空腔,平均粒径为66.97μm。胶体磨IDF的结构疏松,且部分出现断裂和破碎,平均粒径为79.52μm。高压均质和胶体磨改性处理均对IDF的官能团无影响,都具有糖类的特征吸收峰;对IDF的结晶结构和结晶度无影响,仍表现出纤维素I型的特征衍射峰。与未处理的IDF相比,高压均质IDF的持水力、膨胀力和持油力分别提高31.70%,78.87%,38.92%,对NO_2~-的吸附能力并无明显增加,对Cd~(2+)的吸附能力提高7.53%。胶体磨IDF的持水力、膨胀力和持油力分别提高19.93%,47.94%,32.97%,对NO_2~-的吸附能力增加8.20%,对Cd~(2+)的吸附能力并无明显增加。     

不同工艺制备刺梨果渣膳食纤维及品质分析

以可溶性膳食纤维（SDF）得率为评价指标,确定化学法、酶法和发酵法制备刺梨果渣膳食纤维最佳制备工艺,对3种方法膳食纤维样品及原果渣进行品质分析。结果显示,绿色木霉发酵法为最佳处理方法,优化条件下可溶性膳食纤维得率为12.75%,比原果渣可溶性膳食纤维提高了74.42%。3种处理方法得到的总膳食纤维（TDF）膨胀力、持水力、持油力、胆固醇吸附力均比原果渣有所提高。电镜扫描发现3种处理方法均使纤维结构发生不同变化。红外光谱扫描分析显示,刺梨可溶性膳食纤维含有糖的特殊吸收峰,处理条件不同导致官能团组成不同,酶法和发酵法可溶性膳食纤维含有半乳糖,化学法可溶性膳食纤维没有。     

薇菜水不溶性膳食纤维提取工艺研究

采用碱浸法提取薇菜中水不溶性膳食纤维。首先对影响碱法提取率的4个因素：料液比、碱液浓度、反应温度及提取时间进行了单因素实验,再通过正交实验确定了碱法最佳工艺条件。结果表明：料液比为1∶10、碱液浓度为0.5mol/L、碱浸温度为65℃、碱浸时间为1h,在此工艺条件下,薇菜水不溶性膳食纤维的提取率达到41.81%。     

柠檬皮渣膳食纤维制备工艺研究

以柠檬皮渣为原料,分别采用水和95%的乙醇为溶剂在不同温度下制备柠檬膳食纤维,并测定其膳食纤维组成和理化特性。结果表明：柠檬膳食纤维制备的工艺条件采用水在室温下处理1min,并进行冷冻干燥,可以得到总黄酮含量、VC含量和持油力较好的产品;柠檬膳食纤维制备的工艺条件采用乙醇在60℃处理90min,并进行冷冻干燥,可以得到SDF/IDF（可溶性膳食纤维/不溶性膳食纤维）比值合理、持水力、粘度、白度都较好的产品。     

刺梨果渣膳食纤维提取改性及生物活性研究进展

[1]:刺梨主要分布于我国西南山区和丘陵地带,因刺梨富含多种氨基酸、碳水化合物、维生素及矿物质,以及黄酮、多酚和膳食纤维,成为贵州省推动“精准扶贫”、实施“乡村振兴战略”的重要支柱产业之一。目前,刺梨主要以开发饮料为主,刺梨果渣是刺梨经榨汁后得到的副产物,含有丰富的膳食纤维,是一种优质膳食纤维原料。膳食纤维素有“第七大营养素”之称,分为可溶性膳食纤维和不可溶性膳食纤维,两者均具有重要的生理功能。本文综述了国内外刺梨果渣膳食纤维的提取、改性及生物活性的研究进展,并对刺梨果渣膳食纤维提取改性研究中存在的问题及发展趋势进行总结展望,以期为刺梨果渣膳食纤维的利用提供理论依据。     

小麦麸皮中膳食纤维提取工艺与应用的研究

论述了国内膳食纤维的常用提取工艺,讨论了微波辐射在提取膳食纤维中的应用,概述了膳食纤维在食品中的应用状况及其对食品品质的影响。     

三种不同改性方法对甘薯渣不溶性膳食纤维改性效果的研究

该研究采用胶体磨湿法粉碎法、超声波辅助酸法、纤维素酶法3种方法处理甘薯渣不溶性膳食纤维(insoluble dietary fiber,IDF),比较改性前后IDF粒径分布、微观形态,并测定分析其理化性质.结果表明,与未改性甘薯渣IDF相比,3种改性方法改性之后,甘薯渣IDF的粒径、分散指数显著降低(P<0.01),持...     

不同处理方式对豆渣可溶性膳食纤维得率及理化特性的影响

目的 为探究不同处理方式对豆渣中可溶性膳食纤维得率及豆渣理化特性的影响,提高其综合利用价值。方法 以豆渣为原料,可溶性膳食纤维得率为指标,通过单因素试验确定不同处理方式(挤压、微波、挤压-微波联用、微波-挤压联用)的最佳工艺条件,并考察不同处理方式对豆渣结构和理化特性的影响。结果 最佳挤压条件为物料水分50%、机筒温度150 ℃、螺杆转速220 r/min,最佳微波条件为微波功率500 W、料液比为1:15、微波时间为6 min,在最佳的挤压、微波、挤压-微波和微波-挤压处理条件下,豆渣中可溶性膳食纤维得率分别为7.48%、6.85%、8.22%和7.71%;通过红外光谱发现豆渣经过处理后分子结构中的氢键被破坏;四种处理方式均未改变豆渣的晶体结构;挤压和微波处理都会使豆渣发生团聚现象;经过处理后豆渣的热稳定性和持水性下降、持油性升高,联用处理会降低豆渣的溶胀性。结论 联用处理改变豆渣的结构进而影响其性质及可溶性膳食纤维含量,研究结果为提升豆渣在食品领域的应用提供参考。     

花生壳膳食纤维化学改性工艺参数优化及品质分析

为改善花生壳膳食纤维可溶性,以花生壳膳食纤维为原料,氢氧化钠为催化剂,一氯乙酸为醚化剂,对花生壳膳食纤维的醚化改性进行了研究。通过单因素、正交实验优化化学改性最佳工艺参数,通过SEM电镜扫描观察及物化特性研究对其品质进行分析。结果表明,花生壳膳食纤维化学改性最佳工艺参数为:Na OH浓度30%,碱化温度30℃,一氯乙酸浓度30%,醚化温度55℃,料液比1∶8g/m L。改性后的花生壳膳食纤维结构及物化特性得到改善,结构松散,组织均匀,分散性良好,膳食纤维含量为16.8%,品质良好。      

不同提取方法对鲜食大豆荚膳食纤维抗氧化特性的影响

以鲜食大豆荚为原料,通过碱法、酶法、超声辅助酶法及微波辅助酶法提取水溶性膳食纤维和不溶性膳食纤维,测定其总黄酮含量、还原能力、DPPH自由基清除能力和羟自由基清除能力以研究其抗氧化特性,并与市售大豆膳食纤维作比较。结果表明,各种方法提取的鲜食大豆荚膳食纤维的总黄酮含量及抗氧化特性均高于市售大豆膳食纤维,鲜食大豆荚水溶性膳食纤维的抗氧化特性高于不溶性膳食纤维,酶法、超声和微波处理能提高鲜食大豆荚膳食纤维的抗氧化特性。      

水浴和超声法制备苹果渣可溶性膳食纤维及其性能的研究

以苹果渣为原料,研究水浴法和超声法制备苹果渣可溶性膳食纤维及其性能。结果表明水浴法制备苹果渣可溶膳食纤维的适合工艺条件为:水浴温度80℃,水浴pH5,水浴料液比1∶20g/mL和水浴时间90min,在此条件下苹果渣SDF得率为12.76%;超声法制备苹果渣可溶膳食纤维的适合工艺条件为:超声温度60℃,超声pH5,超声料液比1∶20g/mL,超声时间45min和超声功率225W,在此条件下苹果渣SDF得率为14.14%。与水浴法相比超声法能加快苹果渣组织水解,扫描电镜分析表明超声对苹果渣纤维表面的微结构有破坏作用。在相同浓度下,苹果渣SDF抗氧化活性比苹果渣抗氧化活性高很多,但都远低于商业合成抗氧化BHA。      

改性方法对豆渣膳食纤维的结构影响研究

采用X射线衍射(XRD)和红外光谱技术,考察酶解改性、高温蒸煮改性以及高温蒸煮结合酶解改性对豆渣膳食纤维(DF)结构的影响。结合几种改性方法制备豆渣DF,运用XRD及红外光谱技术检测DF的结构特性。结果表明:酶解、高温蒸煮及其结合改性方法主要都是影响豆渣DF中的非结晶区结构,或部分破坏结晶区结构,使这些结构组分溶出或转化为水溶性成分溶出,从而达到改性目的;改性方法对豆渣DF的结晶区结构不会完全破坏。此外,XRD技术和红外光谱技术相结合,可作为研究DF的有效技术手段。     

发酵法制取刺梨果渣膳食纤维工艺优化及其特性分析

目的:通过混合菌种发酵刺梨果渣,提高总膳食纤维(TDF)含量,改善其理化特性,为刺梨果渣TDF的产业化生产与产品开发提供参考。方法:在单因素实验基础上,根据Box-Behnken实验设计以膳食纤维得率为响应值优化最佳工艺。结果:制取刺梨果渣可溶性膳食纤维最佳工艺为:混合菌种嗜酸乳杆菌(Lactobacillus acidophilus) GIM.1.208、戊糖乳杆菌(Lactobacillus pentosus) CICC.22210和生香酵母(Aroma-producing yeast)比例1:2:1、料液比1:5、接种量10%、发酵温度30℃、发酵时间52 h,此条件下SDF得率达11.590%,较原果渣提高76.53%,发酵法得到总膳食纤维(TDF)膨胀力、持水力和持油力均比原果渣有所提高。结论:微生物发酵法制备膳食纤维的同时能有效提高其品质指标,是一种简便的高品质膳食纤维制备方法。     

纤维素酶对苹果肉渣膳食纤维物化特性的影响

以苹果肉渣为原料,采用X-cell纤维素酶法对苹果肉渣中的水溶性膳食纤维进行提取及工艺优化,对其持水力、膨胀力、表观黏度以及超微结构等物化性质进行分析。得出X-cell纤维素酶优化工艺条件为:酶用量75 U/g,酶解温度50℃,最适pH值为4.6,酶解时间为5 h。在该条件下,可溶性膳食纤维提取率可达18.90%。改性后滤渣水不溶性膳食纤维的持水力和膨胀力有所提高;可溶性膳食纤维溶解性较高,其表观黏度降低。在红外光谱图下,改性前后的膳食纤维都有糖的特征吸收峰,并在电镜下观察可得其超微结构也有所改变。