Effects of Sodium Fertiliser on the Chemical Composition of Perennial Ryegrass and White Clover Leaves of Different Physiological Ages

A field experiment was conducted to examine the effects of applying sodium fertiliser on the chemical composition of perennial ryegrass and white clover leaves of different physiological ages. When no sodium fertiliser was applied the cation concentrations increased up to the point of senescence in grass leaves and then declined in the dead leaves. Sodium fertiliser increased the contents of sodium from 6 to 9 g kg^-1 DM and magnesium from 2·2 to 3·4 g^-1 kg DM in young grass leaves, but both declined to a low level in dead leaves. It decreased the content of potassium in young grass leaves and calcium in older leaves. Clover leaves were less responsive to sodium fertiliser than grass, but older clover leaves had an increased sodium content and reduced calcium content when sodium was applied. All clover leaves responded to sodium by increasing chloride and reducing magnesium contents. The nutritional value of grass, but not clover, was reduced by sodium fertiliser, with an increase in fibre content and a decrease in crude protein content and DM digestibility. This probably occurred because of the high content of sodium in the herbage without sodium fertiliser. It is concluded that young grass leaves tend to be more responsive to sodium fertiliser than old leaves, and that clover is less responsive than grass. © 1997 SCI.     

金边黄杨叶、茎挥发油成分分析及抗肿瘤活性研究

分析研究金边黄杨叶、茎挥发油的主要成分及其抗肿瘤活性。以超临界二氧化碳萃取金边黄杨叶、茎挥发油,利用气相色谱-质谱联用技术(GC-MS),经过NIST08谱库检索对比,从中分别,叶挥发油鉴定31个化合物,主要成分有:棕榈油酸(17.11%)、苯甲醛(10.66%)、(Z)-3-己烯-1-醇(8.93%)、正十六烷酸(7.92%)、苯甲醇(6.99%)、肉豆蔻酸(6.13%)、正十五烷酸(6.06%)。茎挥发油鉴定33个化合物,主要成分有:丙二醇单甲醚(12.20%)、正十六烷酸(5.52%)、6,6-二甲基二环[3.1.1]庚-2-烯-2-甲醇(5.17%)、2,4-二叔丁基苯酚(5.08%)。应用四甲基偶氮唑盐(MTT)法检测抗癌活性,结果叶挥发油对对肺癌细胞A549和胃癌细胞SGC-7901抑制最强,其IC50值分别为2.77μg/m L、3.78μg/m L,对比研究表明正十五烷酸是叶挥发油中抑制两种癌细胞的主要活性成分。     

Effects of sodium and potassium fertilisers on the composition of herbage and its acceptability to dairy cows

Fertilisation of herbage with Na can increase acceptability to cows, but the influence of fertiliser rate and fertilisation by K is unknown. In experiment 1, ten cows were grazed on pasture plots that had just been fertilised with 0–132 kg-Na ha⁻¹ (current Na) and had received 0–64 kg-Na ha⁻¹ in the previous grazing season (residual Na). Herbage Na concentration increased in proportion to current Na from 2·7 to 4·9 g-Na kg⁻¹ dry matter (DM) and also increased with increasing residual Na from 2·2 to 4·5 g-Na kg⁻¹ DM. Herbage K concentrations were low (10 g kg⁻¹ DM at 0 kg-Na ha⁻¹) and were only slightly reduced by Na fertiliser. Herbage Mg and Ca concentrations and DM digestibility were maximum at 66–99 kg-current-Na ha⁻¹. Cows grazed current-Na-fertilised plots to a lower height and spent more time grazing them. In experiment 2, pasture plots received no fertiliser, low and high isomolar and independent applications of Na and K or a combination of the two. The herbage was more mature than in experiment 1 and Na concentration of the herbage without Na fertilizer was high (5 g kg⁻¹ DM). Na fertiliser, therefore, only slightly increased Na concentration, more in clover than in grass, and had little effect on K concentration. K fertiliser increased K concentration from 16 to 20 g kg⁻¹ DM and reduced Na concentration to 3·5 g kg⁻¹ DM. Sodium fertiliser, therefore, only increased the acceptability of herbage to cattle when herbage Na concentrations were initially low (less than 5 g kg⁻¹ DM) and were increased substantially by the application of the fertiliser. © 1998 SCI.     

黔南烤坏烟与正常烟叶主要化学成分含量差异

为了明确烤坏烟与正常烟叶的内在质量差异,本研究采用BRAN+LUEBBE AA3型连续流动分析仪测定了K326品种烤后中部叶和上部叶的5种烤坏烟与正常烟叶（C3F和B2F）的主要化学成分含量。结果表明,与正常烟叶相比,烤坏烟的总糖、还原糖含量和糖碱比均大幅度降低,均为不适宜或极不适宜;烟碱、总氮和蛋白质含量明显提高。5种烤坏烟的总糖含量、还原糖含量的平均值,中部叶分别比正常烘烤的C3F低53.5%和50.6%,上部叶分别比比正常烘烤的B2F低39.6%和35.3%;中部叶烤坏烟的烟碱、总氮和蛋白质含量平均值分别比正常烘烤的C3F高31.4%、40.6%和28.6%,上部叶分别比正常烘烤的B2F高24.5%、36.4%和21.2%;中部叶烤坏烟的还原糖/烟碱平均值比正常烘烤的C3F低62.0%,上部叶则比正常烘烤的B2F低47.8%。可见,烤坏烟的主要化学成分含量大多不适宜、不协调。     

人参茎叶多糖提取工艺的研究

以长白山人参茎叶为原料,采用水提醇沉淀法提取人参茎叶中的多糖,用苯酚-硫酸法测定多糖的含量。以多糖提取率为指标,通过单因素试验和正交试验设计对提取工艺进行优化。评价提取温度、提取时间、料液比、p H值4个因素对多糖提取效果的影响,并确定最优提取工艺为:提取温度90℃,提取时间4 h,料液比1∶25(g/mL)、p H 5.0。在此条件下,人参茎叶多糖的提取率为5.64%。     

遮阴处理对茶树叶色表型及生化成分的影响

以\     

漂烫时间对铁核桃雄花序营养成分含量及抗氧化活性的影响

以‘黔核7号’核桃雄花序为材料,研究不同漂烫时间(0、3、6、9、12、15 min)对核桃雄花序主要营养品质及抗氧化活性的影响。结果表明,漂烫显著降低了核桃雄花序中的灰分、脂肪、蛋白质等常规营养素含量;漂烫3 min可溶性糖、淀粉、可滴定酸、灰分含量明显降低;脂肪含量在漂烫6 min后明显下降;粗纤维和蛋白质含量则在漂烫9 min和12 min后明显降低。漂烫处理对K、Fe、Mn和Zn含量损失严重,其次是Cu、P和B;Mg和Ca含量在漂烫过程中显著升高。漂烫过程中,必需氨基酸的损失率高于非必需氨基酸和总氨基酸,苯丙氨酸和缬氨酸损失率最高。抗氧化物质总酚和总黄酮含量均随漂烫时间的延长而明显下降,抗氧化能力也随之下降,且铁离子还原能力降幅大于1,1-二苯基-2-三硝基苯肼自由基清除能力。结论:为最大程度地保持核桃雄花序的营养价值,在加工和烹饪过程中漂烫时间应控制在3 min以内。     

The effect of supplementation of a white clover or perennial ryegrass diet with grape seed extract on indole and skatole metabolism and the sensory characteristics of lamb

Condensed tannin in the form of a grape seed extract (GSE) was dosed to weaned wether lambs fed white clover (WC) or perennial ryegrass (PRG) over a 9‐week period to determine whether the ‘pastoral’ flavour and odour of meat could be altered. The concentrations of the pastoral flavour compounds indole and skatole were determined in the rumen fluid, blood plasma and intermuscular fat. The odour and flavour of fat and meat from the slaughtered lambs was assessed by a trained panel. The rumen fluid and blood plasma concentrations of indole and skatole were higher in those lambs fed WC compared to PRG (P < 0.05) and the overall meat flavour intensity was greater when feeding WC (P < 0.01). The observed concentration of indole and skatole in the fat between WC and PRG feeding treatments was not statistically different. Power analysis indicated that increasing the number of lambs per treatment group from 20 to 65 would result in a higher fat skatole concentration (P < 0.05) being detected in lambs fed WC compared to PRG. Dosing with GSE gave a small reduction in skatole concentration in the rumen fluid and reduced plasma concentration of indole and skatole (P < 0.001). Odour and flavour scores of the fat and meat samples were not particularly high however, dosing with GSE lowered the overall and sweet odour and the sheepy, camphor, faecal and barnyard flavour (P < 0.05). Although the plasma concentration of indole and skatole suggests that GSE reduced indole and skatole formation, the intermittent supply of the GSE to the rumen environment was not sufficient to reduce their concentration in the fat. Hence, the small difference in the scores for pastoral odour and flavour attributes associated with GSE treatment may arise from other unknown factors. From a primary investigation, there was no difference in the concentration of indole and skatole in fat samples collected from carcasses before and after chilling. Further investigations into meat pastoral flavour are warranted through feeding condensed tannin‐containing forages. Copyright © 2007 Society of Chemical Industry     

Concentration of indoles and other rumen metabolites in sheep after a meal of fresh white clover,perennial ryegrass or Lotus corniculatus and the appearance of indoles in the blood

The objective of this study was to determine the effect of feeding three fresh forage diets, white clover (WC), perennial ryegrass (PRG) and Lotus corniculatus (LC), on the formation of indole and skatole in the rumen of sheep. The formation of indole and skatole in the rumen and their appearance in the blood were also compared. Peak rumen indole and skatole concentrations per kg crude protein intake (CPI) were significantly higher when feeding WC compared with PRG and LC (P < 0.05) and this was associated with a significantly higher rumen concentration per kg CPI of ammonia, branched chain volatile fatty acids, total nitrogen and soluble nitrogen (P < 0.05). Greater indole and skatole concentrations when feeding WC can be attributed to high solubility and rapid degradation of the forage protein. LC had a similar nutrient composition to WC, but the condensed tannins in LC slowed protein degradation and reduced indole and skatole formation. Indole and skatole concentrations peaked in the plasma 1–2 h after the end of feeding, indicating that skatole and indole are rapidly absorbed from the rumen into the blood. High indole and skatole formation with low intakes of WC indicates that the WC component of traditional New Zealand pastures may be the primary cause of undesirable pastoral flavours that result from the presence of indoles in meat. To ameliorate undesirable flavours, producers reliant on pastoral systems will need to consider using alternative forages such as LC to reduce protein solubility and degradation rate. Copyright © 2007 Society of Chemical Industry     

An Overview on Chemical Composition,Bioactivity and Processing of Leaves of Cinnamomum tamala

Dried leaves of Cinnamomum tamala, also known as Indian bay leaves, are a lesser-known spice used in the Indian subcontinent. It imparts a warm, peppery, clove-cinnamon like flavor to a variety of food preparations. Besides food applications, the leaves have also been traditionally used for curing a number of ailments and for other perceived health benefits. They find mention in the Aurvedic, Yunani, and other traditional medicinal literature. This review summarizes the effect of Cinnamomum tamala leaves on biological systems such as immune system, gastro-intestinal tract, liver and its antioxidant, antidiabetic, anti-inflammatory, anticancer, and antimicrobial activity. Chemical components that may be responsible for its flavor as well as bioactivity, have also been discussed.     

烟梗化学组分分析及其制浆与配抄纸张性能研究

本研究通过水热预处理-机械磨浆方式制备烟梗纸浆纤维,并与漂白硫酸盐阔叶木浆配抄纸张。烟梗化学组分析表明,烟梗原料中木质素和综纤维素含量较低（木质素含量为5%~8%、综纤维素含量为29%~35%）、抽出物和灰分含量较高（抽出物含量>50%、灰分含量为~15%）,比较适宜制备机械浆纤维。探究水热预处理条件、H₂O₂漂白工艺参数以及配抄条件对烟梗纤维和纸张性能的影响。结果表明,80 ℃、90 min的水热预处理后通过H₂O₂漂白60 min（H₂O₂用量3%）,可以制备纤维重均长度为0.395 mm、重均宽度为32.3 μm、扭结角为98°、卷曲指数为15.3%的烟梗浆纤维;利用制备的烟梗浆纤维与漂白硫酸盐阔叶木浆在质量比3∶7配抄条件下,所制纸张松厚度、白度、不透明度、撕裂指数和抗张指数分别为1.68 cm³/g、62.1% 、94.6%、5.92 mN·m²/g和33.8 N·m/g。     

红薯茎叶化学组成的研究进展

本文综述了近年来国内外对红薯茎叶化学组成的研究成果,着重介绍了其中具有生物活性的成分,同时展望了红薯茎叶今后的研究方向。     

真空回潮对烤后叶片结构、化学成分及感官质量的影响研究

本文研究了两种打叶复烤模式的对比试验,取两种模式烤后烟叶进行叶片结构、化学成分和感官质量检测、分析和评吸. 结果表明:"真空回潮"后打叶复烤,烤后烟叶大中片率(>12. 7 mm叶片率)和长梗率有所提高;化学成分协调性有所提高;可以一定程度减少杂气、提高余味舒适程度.     

桑叶多糖的化学组成及其对胰脂肪酶的抑制作用研究

将复合酶辅助热水提取所得的桑叶粗多糖依次进行脱蛋白和脱色处理后得到桑叶多糖,研究其化学组成和对胰脂肪酶的抑制作用及作用类型.结果 表明,桑叶多糖的总糖含量为58.28％,其单糖组成及摩尔比为甘露糖∶鼠李糖∶葡萄糖∶半乳糖∶木糖∶阿拉伯糖∶葡萄糖醛酸∶半乳糖醛酸=8.61∶23.42∶4.23∶12.73∶1.31∶3....     

Controlling the formation of indole and skatole in in vitro rumen fermentations using condensed tannin

Indole and skatole are formed in the rumen from the fermentation of tryptophan and have been correlated to the presence of undesirable pastoral flavours in meat from grazing ruminants. A series of four in vitro rumen fermentation experiments was carried out to determine the effectiveness of condensed tannin (CT) for reducing the formation of indole and skatole. Experiment 1 utilised fresh white clover (WC; Trifolium repens) in ratios with the CT‐containing forage Lotus pedunculatus (LP; 97 g CT kg^?1 dry matter (DM)). Increasing the ratio of LP to WC decreased the formation of indole and skatole. Experiments 2 and 3 used extracts of CT from LP and grape seed added to incubations of fresh non‐CT‐containing WC or perennial ryegrass (PRG; Lolium perenne). Including the CT extracts in incubations at 40 and 80 g kg^?1 DM was more effective at reducing indole and skatole formation than lower concentrations of CT extract (P < 0.05). Including fresh LP in ratios with WC gave a linear decrease in indole and skatole concentration (indicating dilution), while including a CT extract in the incubations gave an exponential decrease in indole and skatole concentration (suggesting binding). Experiment 4 elucidated the mechanisms behind the action of CT by delayed addition of tryptophan and polyethylene glycol (PEG) to incubations of LP. Rumen microbes that were exposed to CT of LP in planta for up to 6 h and then provided with tryptophan were still able to convert tryptophan to indole and skatole. Adding PEG to incubations of LP after 6 h inhibited the activity of plant CT and increased the availability of substrate for indole and skatole formation. These studies have shown that a higher concentration of CT is more efficient for reducing indole and skatole formation and that CT contained within plants acts differently in in vitro rumen fermentations than additions of extracted CT. Under the conditions of these experiments, there was no evidence that CT contained in LP affected the protein present in WC in a mixed fermentation. Copyright © 2007 Society of Chemical Industry     

海南雪茄烟叶外观质量与化学成分的关系研究

为研究雪茄烟叶外观质量与化学成分之间的关系,对海南种植的巴西3号、古引4号、H211、D系和H382等5个不同品种（系）雪茄烟叶进行外观质量和数字化评价,利用统计学方法分析其与雪茄烟叶化学成分的关系。试验结果表明,不同品种雪茄烟叶中总植物碱含量、钾含量和碱糖比在化学成分差异中起主导作用;化学成分中总植物碱含量、钾含量、碱糖比、碱钾比与外观质量指标的身份、油分和成熟度的相关性达到极显著水平;叶片结构与钾含量和碱糖比的相关性达到显著水平。回归分析结果表明,雪茄烟叶品种和外观质量指标的身份、油分可以较好地反映烟叶中总植物碱含量、碱钾比、氯离子含量的变化。     

不同采收期黄参茎叶化学成分及生物活性变化

本文分析了不同采收期黄参茎叶（SLSG）的化学成分及生物活性变化，以期为该资源的进一步开发利用提供新信息和科学建议。结果表明对于SLSG中的大多数营养物质，其在秋季采收样品中的含量高于春季采收样品，在次年采收样品中的含量高于同年采收样品。通过体外模拟消化发现，SLSG对于大部分矿物元素有较好的释放率。SLSG对氨基酸的释放率，尤其是色氨酸、甘氨酸、脯氨酸和谷氨酸（约为6%～11%），略低于其他营养物质。L7G和A7O是SLSG中主要的酚类物质，并且在模拟血清吸收中检测出48%～55%的总酚和40%～70%的单体酚。SLSG具有良好的抗氧化能力、α-葡萄糖苷酶抑制作用及体外保肝作用。多酚类物质和氨基酸是这些生物活性功能的主要来源。采收期T4的大多数指标测定结果最优，包括Ca、Zn、Cu、Se、Na、P、酚类物质含量，抗氧化能力，α-淀粉酶及α-葡萄糖苷酶抑制作用等。上述结果加深了对SLSG化学成分及生物活性的认识，并且为该资源的进一步开发利用提供了新信息和科学建议。     

茶叶加工过程对咖啡叶化学成分和抗氧化活性的影响

本研究采用茶叶加工方法对咖啡叶进行加工,探索茶叶加工步骤（包括萎凋、揉捻、发酵、干燥）对不同叶龄咖啡叶的基础成分、植物化学成分和抗氧化活性的影响。结果表明,加工步骤和叶龄对基础成分、植物化学成分和抗氧化活性有不同程度的影响。咖啡叶中水浸出物的含量在整个加工步骤中总体呈下降趋势;可溶性糖的含量在前三个步骤中呈下降趋势,但是干燥后其含量有所上升;萎凋使咖啡幼叶中的游离氨基酸含量提高,然而从发酵步骤开始降低。咖啡因含量在幼叶中呈降低趋势但在成熟叶中变化不显著;芒果苷和芦丁含量在萎凋时升高,揉捻和发酵时降低,干燥时升高;绿原酸含量在发酵步骤结束之前呈下降趋势,干燥时又升高;总酚和总黄酮含量以及抗氧化活性的基本变化趋势与绿原酸相似。鲜咖啡幼叶的水分含量、可溶性糖、可溶性蛋白、植物化学成分和抗氧化活性均显著高于成熟叶且在相同步骤下其含量在幼叶与成熟叶中存在显著性差异。发酵2 h的基础成分含量、植物化学成分含量和抗氧化活性高于48 h。不同茶叶加工步骤对咖啡叶的植物化学成分和抗氧化活性具有不同的影响,其中发酵的时间对除了水分之外的基础成分和植物化学成分的影响最为显著。     

Effectiveness of Alkali and Sodium Bicarbonate Treatments on Sugar Palm Fiber: Mechanical,Thermal, and Chemical Investigations

ABSTRACT

Sugar palm fiber (SPF) as one of the attractive natural fibers to reinforce matrix is gaining attention. This is largely due to its similar properties when compared with other established natural fibers. The aim of this study is to investigate the effectiveness of sodium bicarbonate as a treatment chemical for SPF in comparison with established alkaline treatment. Both treated and untreated fibers were characterized and it was found that the treated fiber shows an increase in crystallinity, thermal stability, and surface’s roughness when compared with the untreated. Among the two different treatments, SPF treated with alkali has an initial decomposition temperature of 255.47°C, while sodium bicarbonate treated and untreated fibers have 250.19°C and 246.76°C, respectively. In both cases, the thermal stability of the fiber was improved. Also, as revealed by the X-ray diffraction (XRD) analysis, the crystallinity index of SPF treated with alkali and sodium bicarbonate increased by 18.43% and 13.60%, respectively, when compared with untreated fiber. In conclusion, the investigation proved that treatment with the sodium bicarbonate has a significant effect on the physicochemical properties of SPF and the chemical could be an alternative chemical for treating other cellulose fibers.     

品种及平衡施肥量对初烤烟叶化学成分的影响

研究了不同品种以及平衡施肥量对初烤烟叶 8种化学成分及两个比值的影响。结果表明 :施肥量间烟叶总N、总糖、还原糖及糖 碱比、施木克值呈显著差异 ,其余成分差异不显著。随着施肥量的增加烟叶总N含量提高 ,总糖、还原糖、糖 碱比、施木克值降低 ;各品种间除烟碱含量外 ,其余成分和比值差异显著 ;二因素对烟叶化学成分的交互作用不显著