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1.
This work examined the processing yields, physico-chemical characteristics, and bioactive properties of Canadian organic cranberry and blueberry pomace and phenolic-enriched extractives. The ethanol extracts from each berry contained three to four times the soluble solids and sugar contents compared to the pomace. The lipid content of organic cranberry pomace (4.44%), cranberry ethanol extractives (3.86%), and blueberry ethanol extractives (4.44%) were significantly lower than the lipid content of the organic blueberry pomace (5.42%). The organic blueberry pomace showed higher protein content (8.41%) than organic cranberry pomace (5.76%); however, both organic cranberry and blueberry ethanol extracts showed similarly low protein contents. Significant differences were observed in the mineral and elemental contents of both pomaces and their extractives. Total phenolics, tartaric esters, flavonols, anthocyanins, and antioxidant activities were increased by two to three times in both organic cranberry and blueberry ethanol extracts compared to their respective pomaces. The major anthocyanins detected in organic blueberry pomace and ethanol extracts were peonidin 3-glucoside, malvidin 3-galactoside, malvidin 3-glucoside, and cyanidin 3-arabinoside. Peonidin 3-galactoside, cyanidin 3-galactoside, cyanidin 3-arabinoside, and peonidin 3-arabinside were the major anthocyanins in the organic cranberry and ethanol extacts. Results indicated that cranberry and blueberry pomace could be used to develop bioactives with antioxidant activity for potential health benefit and/or bioenergy production.  相似文献   
2.
The objective of this study is to determine the properties of G. amplexifolia. In this paper; the chemical composition, including holocellulose, acid-insoluble lignin, 1% NaOH solubility, benzene-ethanol extractives and ash content, was considered for the variability with respect to positions along bamboo culm height (bottom, middle and top), parts along radial direction (inner part and outer part)and ages (1-year and 2- year). The test results were also compared to those of moso that is commonly planted and used in China. This study indicated that both the holocellulosecontent and the lignin content in inner part were lower than ; in outer part, but for extractives and ash content, the reverse was true. Bamboo age also had effect on chemical composition; both the holocellulose content and the ash content in the culm of 1- year were higher than those of 2-year; while the lignin content and the extractive content m the culm of 1- year were higher than those of 2-year. High holocellulose content, low lignin contentand extractive content were advantages of G. amplexifolia.  相似文献   
3.
早在有史以前,人们已经利用那些易于获得的树木提取物为人类提供了许多必需品,以后,不同国家的科学家们经过长期互相协作研究,分离出其有效组分,阐明了它们的结构,作到了化学合成和生物合成,还确定了控制它们在植物中生成的某些生物因素。今天在有机化学上的许多进展都是从175年以前的这些研究中发展而来的。近年技术的发展,质量标准的提高以及价格竞争都要求有特殊性质的原料以满足特殊的需要。当今技术的迅速发展使国际间的出口局限于那些价格低廉、质量较高的基本原料,或具有不能替代的特有成分的产品。在资源日益减少的今日世界必须更重视特定地区再生资源的保护和最大限度的发展,以及生产所需产品的最有效的技术。为此目的,对树木的生理和化学还需要更深刻的认识。  相似文献   
4.
A method for screening wood extractives was developed using cellulose thin-layer chromatography plate (Cell-TLC) separation and was directly applied to bioassays. Wood meal (60 mesh) from nangka (Artocarpus heterophyllus Lamk) heartwood was extracted with hot methanol. The crude extract was separated using a Cell-TLC plate (50 × 50mm). Two broad bands with Rf values of 0.46 and 0.96 were found, and the bands showed completely different effects against the pest termite Coptotermes formosanus Shiraki and the decay fungus Fomitopsis palustris. The band with Rf 0.46 was preferentially consumed by workers of C. formosanus, and it did not show any growth inhibition against F. palustris when the Cell-TLC plate was directly exposed to the organism. In contrast, the band with Rf 0.96 appeared to repel strongly the feeding by C. formosanus and inhibited the growth of F. palustris. It was concluded that the Cell-TLC system was applicable for screening wood extracts consisting of many compounds.  相似文献   
5.
采用硫酸水解法(aldito-acetate procedure)、X射线粉末衍射(XRD)、傅里叶变换红外光谱(FTIR)分析了蒸爆过程中毛竹材加工剩余物纤维聚集态结构及主要化学成分的变化.研究结果表明,(1)毛竹材加工剩余物经蒸爆处理,60%左右的半纤维素水解,木质素低分子化且裸露到纤维表面,易被80%乙醇及木质素溶剂提取,从而实现毛竹材加工剩余物主要组分的有效分离.(2)毛竹材加工剩余物经蒸爆处理,80%乙醇抽提物得率提高,综纤维素得率减少,木质素含量减少:葡萄糖相对含量增加,半纤维素降解明显.(3)210℃处理10 min和220℃处理10 min的蒸爆浆的化学组成变化几乎没有区别,但两者与200℃处理10 min差别较大,210℃处理10 min是毛竹材加工剩余物适宜的处理温度.(4)FTIR结果显示蒸爆处理后在1040~1060 cm-1区的吸收峰分裂为明显的2个峰表明半纤维素降解,1166 cm-1处的吸收强度明显减弱,表明C-O-C键有不同程度的断裂.X-身寸线衍射分析结果显示毛竹材加工剩余物蒸爆处理后纤维素相对结晶度增加.  相似文献   
6.
莫梅英  冷扬  张志 《湛江医学院学报》2007,25(3):250-251,260
目的利用微核试验了解松木刨花和枫木刨花的遗传毒性。方法80只NIH种小白鼠随机分为8组,每组10只。其中3组分别以100、50、12.5g/kg剂量的松木刨花水提取物染毒,另3组分别以100、50、12.5g/kg剂量的枫木刨花水提取物染毒,1组(阳性对照组)以环磷酰胺50mg/kg染毒,1组((阴性对照组)以生理盐水染毒。染毒方法均是先经口染毒,24h后以同样剂量再次灌胃。6h后颈椎脱臼处死动物,制片,观察并计数嗜多染红细胞的微核率。结果以松木刨花及枫木刨花水提取物染毒的各组小白鼠的微核率与阳性对照组比较差异有统计学意义(P<0.01),与阴性对照组比较差异无统计学意义(P>0.05)。结论松木刨花和枫木刨花的水提取物对小鼠的骨髓细胞未见有何致突变性。  相似文献   
7.
植物抗氧化剂研究展望   总被引:13,自引:1,他引:13  
总结了植物多酚、活性多糖、维生素、蛋白质和氨基酸等植物提取物的抗氧化活性主要成分,提出应在原料筛选,提取、分离方法创新,多组分协同作用机理和抗氧化活性成分的构效关系等方面深入研究  相似文献   
8.
ABSTRACT

The connection between chemical composition and anatomy of wood is poorly studied. Abiotic and biotic growth conditions affect the synthesis of structural compounds and the anatomy of wood at the same time as they affect growth. In this study, the wood chemical composition, and connections between wood chemistry and anatomy were studied in downy birch (Betula pubescens Ehrh.) grown on four growth sites possessing mineral and peat soils. Lignin, holocellulose, extractive and ash contents, and effective heating value were analysed and compared with libriform fibre double wall thickness and lumen diameter, vessel size and number, and ray and axial parenchyma numbers. Measured lignin and extractive contents were exceptionally high and holocellulose content low. Correlations between wood anatomy and effective heating value were partly different on different soils. Correlations between holocellulose and anatomy were the opposite of the correlations between other chemical compounds and anatomy. The significant correlations between chemical composition and anatomy were commonly opposite in trees grown on peat than in trees grown on mineral soil. Particularly, vessel characteristics and fibre wall thickness correlated significantly with wood chemistry in trees grown on mineral soil. The connections between wood anatomy and chemistry proved to be soil-dependent.  相似文献   
9.
The relationships existing among the values obtained when extracting the wood of four Argentinean species of Prosopis (P. alba, P. kuntzei, P. nigra, and P. ruscifolia) and one of the Acacia (A. aroma) by several procedures were evaluated and discussed. The used methods were: extraction in toluene/ethanol and hot water; determination of tannic and non-tannic content; measurement of phenolic compounds. Additionally, liquid chromatography (HPLC) was also used in order to quantitatively evaluate the content of (−)-mesquitol, a relatively unusual flavonoid (flavanol type). The total amount of Oxidation Products was also measured. They result from oxidation and polymerization processes of phenolic compounds occurring during heartwood formation, and were not separated during chromatographic analysis. Data evidenced a linear trend (R2 = 0.970) between organic and tannic extractives of all species, and a similar one (R2 = 0.927) between total phenols and tannic (or organic) extractives in the case of heartwood of Prosopis species. Interestingly, for sapwood very different values of organic extracts, tannic content or Oxidation Products type compounds were measured in spite of a similar amount of phenolic substances. Moreover, the various species presented the same peaks in chromatograms, thus evidencing the chemical similarity of compounds but a different quantity between heartwood and sapwood and also among the various species. The observed similarity implied that the various methods of extraction did not really extract only a single class of substances, and that great care must be adopted when using some specific procedures for extractions.Furthermore, the existing relationships between extractives and selected technological properties, namely specific volumetric shrinkage coefficient (BSvol) and natural durability (evaluated in terms of mass loss after fungal attacks in laboratory conditions), were given. It appeared that in heartwood BSvol was well correlated to organic extractives (R2 = 0.984), thus evidencing the microimpregnation of cell walls by extractives, but the fitting quality of the correlation was dependent on the type of extractives used. Analogously, a good relationship between mass loss and phenolic compounds existed (R2 = 0.764), and in this case the value of R2 was even more dependent on the considered extracts. Moreover, the availability of quantitative data on several Prosopis species allowed to consistently evaluate the bioactivity of (−)-mesquitol on the resistance against fungal attack, and the logarithmic form of the relationship between mass loss and (−)-mesquitol content suggested a direct fungicidal activity of this compound. On the other hand, data also evidenced that neither phenolic compounds nor (−)-mesquitol can be considered as the unique and definite factor able to determine the durability of the considered species.  相似文献   
10.
竹柳材因其良好的生物学特性,本世纪初被广泛引种到内蒙古西部干旱和半干旱地区。目前已进入平茬抚育期,间伐竹柳材可以作为人造板工业原材料。通过GB/T2677.2~10-1995、GB/T17660-1999、GB/T6043-2009和硝酸乙醇法,系统测试研究了不同树龄、不同部位的竹柳材的化学成分。结果表明:同一树龄不同部位竹柳材中纤维素、综纤维素、1% NaOH抽提物差异显著。不同树龄竹柳材中纤维素、酸不溶木素、苯醇抽提物和1% NaOH抽提物含量差异显著。通过对竹柳材化学性质的研究,得出竹柳材可以作为人造板材料。  相似文献   
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