叶面喷硒对胡萝卜GSH含量和GSH-PX活性的影响

采用不同浓度的亚硒酸钠进行胡萝卜叶面喷施的田间试验,研究硒对胡萝卜根中谷胱甘肽含量和谷胱甘肽过氧化物酶活性的影响,探讨硒在胡萝卜中的抗氧化功能,结果表明,0-100mg/L的亚硒酸钠溶液进行胡萝卜叶面喷施,胡萝卜根中谷胱甘肽含量和谷胱甘肽过氧化物酶活性分别比对照增加6.31％-82.1％和6.67％-50％,均达到极显著差异.且喷硒浓度为50mg/L为宜.     

苯酚-硫酸法测定北芪菇多糖的含量

采用水提醇沉法从北芪菇中提取水溶性多糖,用Sevage法除蛋白,通过苯酚-硫酸比色法在490nm波长处测定多糖含量.在10-80μg·mL-1范围内,葡萄糖质量浓度与吸光度线性关系良好,相关系数r=0.9985,平均回收率为97.74％,相对标准偏差为2.36％（n=6）,北芪菇中多糖含量为5.45％％.方法快速、简单,稳定性好,可作为北芪菇多糖的常规检测方法.     

大黄种子中蛋白质、多糖和淀粉含量的测定

采用凯氏定氮法、苯酚-硫酸比色法和双波长比色法测定唐古特大黄种子、掌叶大黄种子和药用大黄种子的蛋白质、多糖和淀粉的含量.采用凯氏定氮法测定蛋白质含量,苯酚-硫酸比色法测定多糖含量,双波长比色法测定淀粉含量.唐古特大黄种子的蛋白质和多糖在三种大黄种子中含量最高,分别为21.81％、6.58％,掌叶大黄种子淀粉含量在三种大黄种子中最高,含量为32.95％.三种大黄种子中,蛋白质含量为：唐古特大黄种子＞掌叶大黄种子＞药用大黄种子;多糖含量为：唐古特大黄种子＞掌叶大黄种子＞药用大黄种子;淀粉含量为：掌叶大黄种子＞唐古特大黄种子＞药用大黄种子.大黄种子的蛋白质、多糖、淀粉含量丰富.测定方法精密度、准确度、稳定性均符合生物样品测定要求,可用于大黄种子蛋白质、多糖和淀粉含量的测定.     

益母草多糖的抗氧化性

测定益母草多糖含量和研究其多糖的抗氧化性.利用水提醇沉法提取粗多糖,并利用Sevage法脱蛋白对其进行纯化;采用苯酚-硫酸法测定益母草多糖样品中纯多糖的含量并采用邻苯三酚自氧化法和水杨酸法分别研究益母草多糖清除O2-·和·OH的效果.益母草提取所得多糖样品中纯多糖含量达48.5％,益母草多糖具有较强的清除O2-·和·OH的作用.     

海参胶原蛋白的提取及其基本成分的分析

提取海参中胶原蛋白并分析其基本成分.分别用碱解、酶解法提取胶原蛋白,Folin-酚试剂法测定多糖含量、蛋白含量,运用GC分析单糖成分.海参中多糖含量为14.35％,蛋白含量为0.989％.多糖的成分包括岩藻糖、甘露糖、半乳糖、葡萄糖,其中岩藻糖为主要单糖成分.本法简单,操作方便,实验灵敏,多糖得率高.     

云南昭通产天麻中天麻多糖含量的测定

建立了用苯酚-硫酸法测定云南昭通产天麻中天麻多糖的方法,实验结果表明：该法用于天麻多糖的含量测定时,供试品溶液在180min内显色稳定,RSD=0.351％（n=6）;回收率在97.36％-100.88％之间,平均回收率为99.25％,RSD=1.447％（n=6）.本实验结果可靠,并且该法不受蛋白质的影响.通过回收率实验可知,本法所测多糖含量,准确率较高,重复性较好,且此法简便,灵敏.为其质量标准的研究提供实验依据,并为天麻多糖的进一步研究奠定了基础.     

玫瑰枝叶中可溶性多糖的含量测定

通过单因素试验研究了苯酚-硫酸法测定玫瑰枝叶可溶性多糖含量的最佳实验条件,即6％的苯酚溶液用量为1.0mL、浓硫酸用量为5.0mL,在室温下放置显色15min后于分光光度计488nm波长处测定吸光度.用此方法对生长季不同时期、不同生理状态(开花与未开花)下玫瑰枝、叶多糖含量进行了测定.试验结果显示:玫瑰叶片可溶性多糖含量高于枝条;开花植株的多糖含量高于未开花植株;在生长季不同时期玫瑰枝叶多糖含量呈现V形动态变化趋势.     

黑龙江膜荚黄芪多糖及微量元素Fe、Zn、Cu和Mn的测定

采用水提醇沉法制备黄芪多糖提取物,苯酚-硫酸分光光度法测定多糖的含量,在0.00-0.14mg/mL线性范围内具有良好的线性关系,回收率在94.81%-103.50%.测定黄芪多糖含量为4.3%.采用校准曲线法,用空气-乙炔火焰原子吸收光谱法测定样品中Fe、Zn、Cu和Mn的含量,膜荚黄芪中微量元素含量较高.     

叶面喷硒对胡萝卜品质的影响

采用不同浓度的Na2SeO3进行胡萝卜叶面喷施的盆栽实验,探讨硒对胡萝卜品质的影响.结果表明,叶面喷施Na2SeO3浓度在0.5-50mg/L范围内对维生素C含量均显著提高;浓度在1.0-100mg/L时,磷、总糖、胡萝卜素的含量均高于对照且达到极显著水平.综上所述,叶面喷施Na2SeO3能显著提高胡萝卜品质,喷施浓度100mg/L以下为宜.     

南瓜多糖的测定及南瓜多糖与口感性状相关性的研究

用苯酚-硫酸法测定了96个南瓜品种中多糖的含量,品尝了各种南瓜的口感特征,研究了南瓜的口感特征和多糖含量的相关性.结果显示,不同品种的南瓜中南瓜多糖含量有较大差别,南瓜多糖的含量和南瓜口感的面度存在显著性正相关.测定结果为南瓜新品种的培育与南瓜新产品的开发提供了重要的科学依据.     

Effect of ultrasound treatment on microstructure,colour and carotenoid content in fresh and dried carrot tissue

The aim of the study was to investigate the influence of ultrasound treatment on the carrot tissue microstructure, colour and carotenoids content. To avoid adverse effects of rinsing out substances contained in the raw material, carrot slices were vacuum-packed and treated with ultrasounds in an ultrasonic bath using 21 and 35 kHz frequency for 10, 20 and 30 min. Images of the carrot tissue made by scanning electron microscope were analysed by calculating the cross-section area for each cell. The colour was measured using CIE L^∗a^∗b^∗ method. To determine total carotenoid content spectrophotometric method was used. Obtained results indicate that the structural properties of carrots treated with ultrasound were significantly different from the samples without any treatment and it was clearly noticed during analysing images of scanning electron microscope. There was observed the influence of ultrasound treatment on colour L^∗, a^∗ and b^∗ parameters, especially for carrot treated with ultrasound for 30 min, independent of the applied frequency of the ultrasonic waves. Similarly, sonic treatment resulted in substantial increase of carotenoid in comparison to raw carrot, especially in the case of 35 kHz frequency ultrasounds. Probably, such significant increase is caused by the destruction of the original structure and thus higher extraction ability of these compounds.     

Effect of ultrasound and blanching pretreatments on polyacetylene and carotenoid content of hot air and freeze dried carrot discs

The effect of ultrasound and blanching pretreatments on polyacetylene (falcarinol, falcarindiol and falcarindiol-3-acetate) and carotenoid compounds of hot air and freeze dried carrot discs was investigated. Ultrasound pretreatment followed by hot air drying (UPHD) at the highest amplitude and treatment time investigated resulted in higher retention of polyacetylenes and carotenoids in dried carrot discs than blanching followed by hot air drying. Freeze dried samples had a higher retention of polyacetylene and carotenoid compounds compared to hot air dried samples. Color parameters were strongly correlated with carotenoids (p<0.05). This study shows that ultrasound pretreatment is a potential alternative to conventional blanching treatment in the drying of carrots.     

微波萃取-分光光度法测定灵芝中多糖的含量

通过单因素考察及正交试验优化微波法提取灵芝多糖的实验条件,并选用无水葡萄糖为对照品,5%苯酚和硫酸为显色剂,以分光光度法测定灵芝中多糖的含量。正交试验结果表明:当料液比为1:20(g/mL),微波功率为中高火,微波时间为30min时,得到的灵芝多糖的量最多。各因素对灵芝中多糖得率的影响由大到小依次为:微波功率>微波时间>料液比。在490nm波长下,总多糖浓度在0—14.41μg/mL范围内,吸光度与含量呈良好的线性关系,在10—180min内稳定。该方法操作简便、快速,灵敏度高和重复性好,可用于灵芝及其相关产品的多糖检测。     

富硒蛹虫草中硒多糖的分离与分析

在对人工栽培的富硒蛹虫草中分离提取了水溶性硒多糖,富硒蛹虫草硒多糖的分离纯化方法是采用水提醇沉工艺,粗硒多糖得率为5.76%。系统研究了富硒蛹虫草硒多糖的浸提、纯化、分离条件,苯酚硫酸法测定了富硒蛹虫草的多糖含量为47.5%,分子荧光法测定硒多糖中含硒量为92.3 mg·kg-1。     

Improved mechanical properties of retorted carrots by ultrasonic pre-treatments

The use of ultrasound pre-processing treatment, compared to blanching, to enhance mechanical properties of non-starchy cell wall materials was investigated using carrot as an example. The mechanical properties of carrot tissues were measured by compression and tensile testing after the pre-processing treatment prior to and after retorting. Carrot samples ultrasound treated for 10 min at 60 °C provided a higher mechanical strength (P < 0.05) to the cell wall structure than blanching for the same time period. With the addition of 0.5% CaCl₂ in the pre-treatment solution, both blanching and ultrasound treatment showed synergistic effect on enhancing the mechanical properties of retorted carrot pieces. At a relatively short treatment time (10 min at 60 °C) with the use of 0.5% CaCl₂, ultrasound treatment achieved similar enhancement to the mechanical strength of retorted carrots to blanching for a much longer time period (i.e. 40 min). The mechanism involved appears to be related to the stress responses present in all living plant matter. However, there is a need to clarify the relative importance of the potential stress mechanisms in order to get a better understanding of the processing conditions likely to be most effective. The amount of ultrasound treatment required is likely to involve low treatment intensities and there are indications from the structural characterisation and mechanical property analyses that the plant cell wall tissues were more elastic than that accomplished using low temperature long time blanching.     

地木耳多糖的提取工艺研究

为了筛选地木耳多糖的最佳提取条件,本试验用水提取地木耳多糖,以提取温度、提取时间、液料比和提取次数为主要因素,采用L9(34)正交试验进行提取工艺的优化;用苯酚-硫酸法测定多糖含量后计算多糖得率.结果发现,影响地木耳多糖提取的主要因素由大到小依次为提取温度＞提取次数＞提取时间＞液料比.通过正交试验及其验证试验确定地木耳...     

不同生长年限川党参多糖、总黄酮含量的分析比较

通过对不同生长年限川党参多糖、总黄酮含量的测定为川党参种植作出指导。用苯酚-硫酸法测定不同生长年限的川党参多糖含量,用UV法测定总黄酮含量,并对其结果的差异进行分析比较。三年生的川党参多糖含量最高,而总黄酮含量呈递增关系,四年生川党参总黄酮含量增长率比三年生川党参有放缓趋势,因而在实际川党参种植采收可以选收三年生川党参。以川党参的多糖含量、总黄酮含量为川党参药材质量主要参考指标,结合种植年限等生产成本考虑,采收三年生川党参比较合适。     

ICP-MS法测定茶叶及其多糖提取物中的降血糖相关性元素

采用微波溶样ICP-MS法测定了江西婺源绿茶茶叶、茶叶温水及热水浸提液和茶多糖中降血糖相关性元素(ERBS)的含量,探讨了ERBS含量与茶叶品质老嫩以及茶多糖中ERBS含量与茶叶中ERBS总量的关系。结果表明,茶叶品质老嫩不同,茶叶以及茶多糖中各ERBS含量存在一定差异,由品质差的茶叶提取得到的茶多糖中的ERBS的量较高。茶叶中结合于多糖中的各ERBS占相应ERBS总量的比例在0.03%～9.57%之间,与元素种类、茶叶品质有关。结合于多糖中的ERBS占茶叶ERBS总量的比例,鄣山特级和五级茶分别为1.11%和2.10%,对孤山老叶茶,为0.85%。测定结果可以作为选择提取茶多糖茶叶原料的依据,也可为研究茶多糖可能的降血糖机理提供可靠的无机元素方面的数据。     

Performance of dye-sensitized solar cells based on natural dyes

The natural dyes were successfully extracted from spinach, pitaya pericarp, orange peel, ginkgo leaf, purple cabbage and carrot, and then fabricated a dye-sensitized solar cells (DSSCs). It suggested that the absorption properties of natural dyes were strongly dependent on the types and concentration of pigments, and the purple cabbage exhibited an obvious absorption at 317 nm. Meanwhile, a higher conversion efficiency of 0.157% was obtained as the DSSCs were prepared by using purple cabbage, but the DSSCs showed a poor performance when the carrot was used as natural dyes, just achieved 0.01%. FTIR spectra revealed that purple cabbage showed a better adsorption properties between TiO₂ films and dyes than carrot. The dipping time was further investigated and proved that an optimal dipping time was 6 min, the DSSCs using purple cabbage could achieve 0.146% in photoelectric conversion efficiency.