Development of Morus alba Reinforced Poly-Lactic Acid with Elevated Mechanical and Thermal Properties

This research investigates the mechanical and thermal properties of Morus alba combined with polylactic acid in comparison with other natural fibers. The study uses three different fiber and PLA compositions - 20%, 30%, and 40% respectively - to produce composite materials. In addition, another composite with the same fiber volume is treated with a 4% NaOH solution to improve mechanical properties. The composites are processed by twin-screw extrusion, granulation, and injection molding. Tensile strength measurements of raw fibers and NaOH-treated fibers were carried out using a single-fiber tensile test with a gauge length of 40 mm. It was observed that the NaOH surface treatment increases the resistance against tensile loading and exhibited improved properties for raw fiber strands. The diameter of the fibers was measured using optical microscopy. During this research, flexural tests, impact tests, differential scanning calorimetry (DSC), and heat deflection temperature measurements (HDT) were conducted to evaluate the mechanical and thermal properties of the developed composite samples. The results indicate that the mechanical properties of NaOH-treated Morus alba-reinforced polylactic acid outperform both virgin PLA samples and untreated Morus alba samples.

Evaluation of the Liver Cancer Prevention of Anthocyanin Extracts from Mulberry (<i>Morus alba</i>L.) Variety PR-01

This study aims to evaluate the preventive effects of anthocyanins extracts (MAEs) from mulberry variety PR-01 against N-nitrosodiethylamine (NDEA)-induced hepatocarcinogenesis in rats. It was found that 150 mg·kg-1 MAEs treatment significantly reduced the NDEA-induced hepatic nodules incidence and hepatocellular carcinoma incidence by 58.30% and 41.70% compared to the model group. Meanwhile, MAEs significantly restored the elevated the liver function enzymes, inhibited the tumor necrosis factor alpha and interleukin-6 levels, elevated the serum interleukin-10 and interferon-γ and increased hepatic glutathione-S-transferase and UDP-glucuronosyltransferase 2B1 enzyme activity. Moreover, 150 mg·kg-1 MAEs supplement enhanced glutathione content and the activities of superoxide dismutase, catalase, glutathione peroxidase activities but reduced the malondialdehyde and thiobarbituric acid-reactive substances content by 37.90% and 44.52%. Furthermore, MAEs pretreatment maintained nuclear factor erythroid 2-related factor 2 (Nrf2), Kelch-like ECH-associated protein 1, heme oxygenase-1, and NAD(P)H: quinine oxidoreductase1 stimulation and inhibited the expression of TNF-α, nuclear factor-kappaB (NF-κB), and cyclooxygenase-2 (COX-2), indicating that MAEs exhibit effectively prevention effects against liver cancer via decreased lipid peroxidation, induced Nrf2-mediated antioxidant enzymes and attenuating the inflammatory mediators COX-2 through NF-κB pathway. Thus, MAEs of mulberry variety PR-01 may be used as a good functional dietary supplement against liver cancer.

当年生桑树(Morus alba L.)果枝叶片特征与果实性状的相关性

为揭示叶果间的内在作用规律,以桑树(Morus alba L.)当年生果枝为研究对象,分析不同大小果枝上叶片特征和果实性状的差异及其二者间的相互关系。结果表明:随着果枝由小到大,果枝上的叶片数与总叶干重显著增加,而叶形指数却无显著变化;桑葚数与总桑葚干重也有显著增加,桑葚含水量无显著变化。桑葚数与叶片数、总叶干重、总叶面积及其平均桑葚干重显著正相关。研究结果证实了果实的性状与叶片特征之间存在极密切关系。当年生果枝上的桑葚数量多少取决于果枝上的叶片总数,平均桑葚的干重则与果枝上的平均叶面积显著相关。

Correlation between Different Morus alba L. Leaf Nodes and the Change in Leaf Size or Mass

This paper aimed to explore the correlation between Morus alba L. leaf node and its size or mass change and provide a theoretical basis for the development of scientific Morus alba L. cultivation technology. During 2016-2017,the correlation between Morus alba L. leaf node and its size or mass change was investigated and researched. Results showed that through the correlation coefficient analysis,there was a weakly positive correlation between the leaf node and some indicators such as( leaf length ÷ leaf width) and petiole length,there was a weakly negative correlation between the leaf node and some indicators such as leaf width,( leaf length + leaf width),( leaf length × leaf width) and leaf mass,and there was a weakly negative correlation between the leaf node and the other indicators; there was a highly positive correlation between the leaf mass and some indicators such as Morus alba L. leaf length,leaf width,( leaf length + leaf width) and( leaf length × leaf width),there was a significantly positive correlation between the leaf mass and some indicators such as petiole transverse diameter in width and petiole mass,and there was a weakly positive correlation between the leaf mass and some indicators such as petiole transverse diameter in thickness. In terms of significant level of difference,it was found that there was no significant difference in the correlation coefficients between the leaf nodes on the Morus alba L. shoots and some indicators such as leaf length,leaf width,( leaf length + leaf width),( leaf length × leaf width) and leaf mass; there was an extremely significant difference in the correlation coefficients between the leaf mass and some indicators such as Morus alba L. leaf length,leaf width,( leaf length + leaf width),( leaf length × leaf width),petiole transverse diameter in width and petiole mass; there was no significant difference in the correlation coefficients between the leaf mass and the other indicators. The regression analysis was performed on the leaf node and leaf length,leaf width,( leaf length + leaf width),( leaf length × leaf width),( leaf length ÷ leaf width),petiole length,petiole diameter in width,petiole diameter in thickness,petiole mass and leaf mass. Significance F values were0. 4864,0. 1995,0. 2888,0. 3004,0. 2350,0. 2407,0. 8925,0. 5227,0. 7022 and 0. 2000,respectively,that is,there was an extremely significant difference between Morus alba L. leaf node and petiole diameter in width,there was a significant difference between Morus alba L.leaf node and petiole mass,and there was no significant difference between Morus alba L. leaf node and the other indicators. The comparative analysis of quadratic curve regression equation and linear regression equation was performed on some indicators such as leaf length,and it was found that the R value between the leaf node and petiole diameter in width was in line with the logarithmic curve regression equation,and the other R values of quadratic curve regression equation was larger than the other R values of linear regression equation,indicating that different Morus alba L. leaf nodes,leaf length,leaf mass and other indicators were in line with the quadratic curve regression equation. It was concluded that by investigating the leaf node on the Morus alba L. shoots and regression equation,we could predict the leaf size,leaf mass and other indicators,and we could take the leaf node on the Morus alba L. shoots as a main factor affecting the Morus alba L. leaf size and mass.

Chemical characterization and antioxidative properties of Polish variety of Morus alba L. leaf aqueous extracts from the laboratory and pilot-scale processes

White mulberry tree (Morus alba L) is cultivated throughout Asia and Europe, including Poland. The leaves and root bark preparations from Morus alba have been used in traditional phytomedicine. The objective of the present study was to compare chemical composition and antioxidative activity of aqueous extracts prepared from Polish variety of Morus alba leaves at the laboratory (L) and pilot plant scale (PP) conditions. Proximate composition, phenolic acids profile (HPLC/MS), flavonol glicosides (HPLC/ MS), polyphenols (Folin-Ciocalteu assay), and the antioxidant activity (ABTS and DPPH assay) of the extracts were determined. The main phenolic compounds were identified as gallic, protocatechuic, phydroxybenzoic, vanillic, chlorogenic, caffeic, p-coumaric, ferulic, and sinapic acids. Chlorogenic acid was the main phenolic constituent of both extracts. The flavonols fraction contained rutin, quercetin 3-β-D-glucoside, and kaempferol 3-β-D- glucopyranoside. Total concentration of phenolic compounds were 7.9 g and 14.4 g gallic acid equivalent/100 g extract, and antioxidant activity was 137.1 and 214.1 μMol Trolox equivalent/g dry weight for the PP and L extracts, respectively. We concluded that current pilot plant process is less efficient than laboratory process at the aqueous extraction of bioactive components from Morus alba dried leaves. Potential improvements may include increasing efficacy of the extraction, decreasing losses of bioactive components during the process, or both.

High Phenotypic Variation in Morus alba L. along an Altitudinal Gradient in the Indian Trans-Himalaya

Ten quantitative morphological characters were studied in 56 Morus alba L. trees representing three natural populations from the trans-Himalayan Ladakh region. The altitude of collection sites ranged from 2815 to 3177 m above the sea level(asl). Coefficient of variation(CV) showed high phenotypic variation in M. alba. Linear regression analysis revealed that leaf and fruit size decreases with an increase in altitude. High CV was observed for leaf length, leaf width, petiole length, leaf area, internodal distance, number of nodes, bud length, fruit length, fruit width and fruit weight. Similarly, a high phenotypic plasticity index was observed for bud length, leaf length, leaf width, petiole length, leaf area, inter-nodal distance, number of nodes, fruit length, fruit width and fruit weight. For every 100 m increase in altitude, leaf length, leaf width and leaf area decreased by 1 cm, 0.8 cm and 16.6 cm2, respectively. Analysis of covariance showed a predominant altitudinal effect on the morphological characters in comparison to the population effect. A small change in the altitude caused significant change in the plant morphological characteristics. The present investigation represents to our knowledge the first study addressing phenotypic variation in mulberryalong an altitudinal gradient.

基于指纹图谱与化学计量学的桑叶蜜炙前后差异性标志物研究

目的比较桑叶蜜炙前后化学成分的变化,筛选差异性标志物并进行含量测定,为蜜炙桑叶的质量控制提供参考。方法采用高效液相色谱(HPLC)法建立桑叶蜜炙前后指纹图谱,标定共有峰并进行相似度评价;以生桑叶、蜜炙桑叶共有峰峰面积为指标,运用主成分分析和正交偏最小二乘-判别分析筛选桑叶蜜炙前后差异性标志物,并进行定量分析。结果从10批生桑叶、10批蜜炙桑叶HPLC指纹图谱中分别标定出23、24个共有峰,2类样品图谱的相似度均大于0.97;主成分分析结果显示,生桑叶和蜜炙桑叶分为2类,正交偏最小二乘-判别分析结果显示,峰2、峰H(5-羟甲基糠醛)、峰1、峰17(异绿原酸C)、峰16的变量重要性投影值均大于1;生桑叶、蜜炙桑叶中差异性标志物异绿原酸C的平均含量分别为0.0936、0.1278 mg/g,差异有统计学意义(P<0.05)。结论筛选得到异绿原酸C等5种差异性标志物;桑叶蜜炙后异绿原酸C含量显著升高。

Plants regenerated from mesophyll protoplasts of white mulberry

Morus alba(white mulberry) mesophyll protoplasts were isolated from leaves of 30-45 day old sterile shoots,with protoplast yields of 2.5 x 107 g-1/F.W. after purification. The protoplasts were cultured in a modified K8P liquid medium containing 0.2 mg/L 2,4-D(2,4- Dichlorophe-noxy acetic acid), 1 mg/L NAA(Naphthyl acetic acid) and 0.5 mg/L BA(6-benzylaminopurine). A low plating density (5 x 104/ml) proved to be favourable to the division of protoplast-derived cells. The first divisioll occurred 4 days after culture, and the division frequency reached 24% at 10 days. A number of cell colonies and microcalli formed in 6 weeks. The microcalli were transferred onto MSB medium with 0.5 mg/L NAA and 0.5 mg/L BA for further proliferation. Shoot formation was initiated when the calli of 3-4 mm in size were transferred onto MSB differentiation medium with 0.1 mg/L NAA and 1 mg/L BA. The frequency of shoot formation was 35%. The shoots of 4-5 cm in height were excised from the callus and rooted on half strength MS medium with 0.5 mg/L IBA and 0.1 mg/L BA. After transplantation into pots, the regenerated plants grew vigorously in the phytotron.

Mulberry fruit as an antioxidant component in muesli

The aim of the study was to develop the technology of muesli via analyzing the addition of white mulberry fruit. The first step involved the selection of ingredients from bioactive compounds. Next, the technology of production was developed. Then, the antioxidant activity of new muesli with potentially pro-health model systems was estimated. Muesli was characterized in terms of its basic nutritional value, and antioxidant potential. The ability to inactivate DPPH and ABTS radicals was estimated. In addition, the amount of fat in muesli was calculated. As part of this calculation, fatty acid composition and content of primary and secondary oxidation products were ascertained. The last stage of the project included sensory analysis of the resultant products. Our studies showed that the new product-muesli had high nutritional value, high antioxidant potential and a positive fatty acid composition. And sensory analysis showed that the product was attractive.

蛋白桑叶中蛋白质提取工艺优化及6种蛋白酶酶解物体外降血糖活性分析

为开发利用蛋白桑叶中蛋白质资源,对其蛋白质提取工艺及酶解物体外降血糖活性进行研究。本研究以蛋白桑叶为原料,采用超声辅助碱提酸沉法提取蛋白桑叶蛋白质。通过单因素实验和响应面法优化提取工艺,以α-葡萄糖苷酶抑制率为评价指标,分析不同蛋白桑叶蛋白酶解产物体外降血糖活性。结果表明,蛋白桑叶中蛋白质的最佳提取工艺为:氢氧化钠浓度0.125 mol/L、提取温度40℃、提取时间40 min和液料比37:1 mL/g。在此优化条件下,得到蛋白质提取率实际值为49.59%±0.45%,所得蛋白质等电点为pH3.5,吸水性为6.49±0.49 g/g,吸油性为2.59±0.06 g/g,乳化活性为7.40±0.17 m^(2)/g,乳化稳定性为72.48%±3.03%。研究考察了蛋白桑叶蛋白质的复合蛋白酶酶解物、风味蛋白酶酶解物、碱性蛋白酶酶解物、胰蛋白酶酶解物、中性蛋白酶酶解物、木瓜蛋白酶酶解物体外降血糖活性,其中中性蛋白酶酶解物对α-葡萄糖苷酶抑制效果最佳,其IC_(50)=3.52 mg/mL。本研究认为,此蛋白桑叶蛋白质提取工艺稳定,中性蛋白酶解肽具有较高的体外降血糖活性,为进一步开发蛋白桑叶蛋白质及其多肽资源提供参考。

桑叶茉莉茶对糖尿病小鼠的降血糖作用

目的研究桑叶茉莉茶对糖尿病小鼠的降糖功效,为桑叶茉莉茶产品的研发提供理论基础。方法取60只雄性ICR小鼠,其中10只设为空白组,剩余50只进行一次性腹腔注射四氧嘧啶(0.2g/kg)建立糖尿病小鼠模型,并将模型构建成功的小鼠分为模型组、桑叶茉莉茶低(0.5 g/kg)、中(1.0 g/kg)、高(2.0 g/kg)剂量组。给药4周后,研究不同剂量组对糖尿病小鼠的一般状态、摄食量、饮水量、空腹血糖值、脏器指数及肝脏中丙二醛(malondialdehyde,MDA)、过氧化氢酶(catalase,CAT)水平的影响。结果与空白组相比,模型组小鼠行为呆滞、反应迟缓,其饮水量、摄食量、空腹血糖值及肝、肾、脾脏指数均显著升高(P<0.01),表明糖尿病小鼠模型建立成功;与模型组相比,桑叶茉莉茶各剂量组小鼠行为状态略有好转,且中、高剂量组小鼠饮水量、摄食量、空腹血糖值及肝、肾、脾脏指数均显著降低(P<0.01),肝脏中MDA水平也显著降低(P<0.01),CAT水平显著升高(P<0.01)。结论桑叶茉莉茶具有降低四氧嘧啶型糖尿病小鼠血糖的作用。

Phytochemistry,pharmacology,and clinical trials of Morus alba

The present review is aimed at providing a comprehensive summary on the botany,utility,phytochemistry,pharmacology,and clinical trials of Morus alba(mulberry or sang shu).The mulberry foliage has remained the primary food for silkworms for centuries.Its leaves have also been used as animal feed for livestock and its fruits have been made into a variety of food products.With flavonoids as major constituents,mulberry leaves possess various biological activities,including antioxidant,antimicrobial,skin-whitening,cytotoxic,anti-diabetic,glucosidase inhibition,anti-hyperlipidemic,anti-atherosclerotic,anti-obesity,cardioprotective,and cognitive enhancement activities.Rich in anthocyanins and alkaloids,mulberry fruits have pharmacological properties,such as antioxidant,anti-diabetic,anti-atherosclerotic,anti-obesity,and hepatoprotective activities.The root bark of mulberry,containing flavonoids,alkaloids and stilbenoids,has antimicrobial,skin-whitening,cytotoxic,anti-inflammatory,and anti-hyperlipidemic properties.Other pharmacological properties of M.alba include anti-platelet,anxiolytic,anti-asthmatic,anthelmintic,antidepressant,cardioprotective,and immunomodulatory activities.Clinical trials on the efficiency of M.alba extracts in reducing blood glucose and cholesterol levels and enhancing cognitive ability have been conducted.The phytochemistry and pharmacology of the different parts of the mulberry tree confer its traditional and current uses as fodder,food,cosmetics,and medicine.Overall,M.alba is a multi-functional plant with promising medicinal properties.

Oxidative Stressand Antioxidant Responses in Young Leaves of Mulberry Plants Grown Under Nitrogen, Phosphorus or Potassium Deficiency

The aim of this study was to associate the generation of reactive oxygen species （ROS） with Induced antloxidant responses and disturbed cellular redox environment in the nitrogen-（N）, phosphorus-（P）, or potassium-（K） deftcient mulberry （Morus alba L. var. Kanva-2） plants. The indicators of oxidative stress and cellular redox environment and antioxldant defense-related parameters were analyzed. Oeficlency of N, P or K suppressed growth, accelerated senescence, and decreased concentrations of chloroplastic pigments and glutathione. Lipid peroxidation and activities of superoxide dismutase, ascorbate peroxidase and glutathione reductase were also increased in these N, P, or K deprived plants. Concentration of hydrogen peroxide Increased in plants deficient in N or P. Oeficlency of N or P particularly altered the cellular redox environment as indicated by changes in the redox couples, namely ascorbic acid/total ascorbate decreased in P-, glutathione sulfydryl/total glutathione decreased in N-, and Increased in P-deficient plants. Activity staining of native gels for superoxide dismutase revealed Increased activity as Indicated by Increased intensity of bands, and induction of few new isoforms in P- and K-deficient plants. Oifferences in the patterns of superoxide dismutase isoforms and redox status （ascorbic acid/total ascorbate and glutathlone sulfydryl/total glutathione） Indicate that N-, P-, or K-deficiency altered antioxidant responses to varying extents in mulberry plants.

桑叶活性成分及药理作用研究进展

桑叶是我国传统中药材,其含有多种活性成分,包括酚类、生物碱类、多糖类、氨基酸类及挥发性成分,其中1-脱氧野尻霉素(1-DNJ)、黄酮类、酚酸和多糖类的药用价值较高,具有抗氧化、降血糖、降血脂、抗炎和抗肿瘤等药理作用。本文从活性成分、药理作用两个方面介绍了桑叶的药用价值,为桑叶的质量控制及品种开发利用等相关研究提供参考。

湘7920冬芽组织培养体系的初步建立

为了丰富湖南地区桑树优质种质资源,同时为桑树品种改良与多用途利用提供技术支持,研究以湘7920桑树品种的冬芽为外植体材料,以MS培养基为基本培养基,初步建立了湘7920桑树品种的组织培养体系。结果表明:湘7920冬芽的最佳培养基为MS+1.0 mg/L 6-BA,增殖倍数为3.05,30 d可使冬芽增长27 mm;侧芽最佳培养基为MS+3.0 mg/L 6-BA+0.3 mg/L IBA,15 d可使侧芽增长22 mm;最佳生根培养基为1/2 MS+0.5 mg/L IBA,根系状态良好,生根率为73%,移栽成活率为30%。

桑叶粉对中华鳖生长性能、肝功能及血清抗氧化指标的影响

该文旨在探究桑叶粉[Mulberry(Morus alba L.)Leaf Powder]对中华鳖(Truogx sinensis)生长性能、肝功能及血清抗氧化能力的影响。试验选取120只体重一致的中华鳖幼鳖,随机分为两组,对照组饲喂基础日粮,试验组在基础日粮中添加,试验为期60 d。结果表明:与对照组相比,试验组中华鳖的体形、内脏形态与颜色均未出现明显差别,内脏与体重比、肝脏与体重比等均无显著性差异(P>0.05);谷草转氨酶(AST)、谷丙转氨酶(ALT)、超氧化物歧化酶活性(T-SOD)、丙二醛(MDA)、谷胱甘肽过氧化酶(GSH-PX)没有显著性差异(P>0.05);而总抗氧化能力(T-AOC)试验组显著低于对照组(P<0.05)。提示饲料添加3%桑叶粉不影响中华鳖的生长性能和肝功能,但影响中华鳖的血清总抗氧化水平。

添加乳酸菌和发酵底物对桑叶青贮发酵品质的影响

为开发桑叶作为非常规饲料资源,本试验探讨了添加乳酸菌、葡萄糖或糖蜜对桑叶青贮发酵品质的影响,试验设对照组(C)、乳酸菌组(P)、葡萄糖组(G)、糖蜜组(M)、乳酸菌+葡萄糖组(P+G)、乳酸菌+糖蜜组(P+M),青贮后第7,14,30和60天开窖取样分析桑叶青贮饲料发酵品质。结果表明,添加乳酸菌加速了桑叶青贮过程中乳酸发酵,青贮第7天P,P+G和P+M组乳酸含量已达到C组的6倍以上,pH值降至4.30以下,其中P+G和P+M在青贮结束时降至4.0左右。补充发酵底物并未有效改善桑叶青贮发酵品质,C、G和M组pH值在青贮前30d始终保持在5.85以上,青贮60d时C组为5.96,G和M组分别下降至5.35和5.24,显著(P<0.05)高于P组。整个青贮过程中P组显示最高的乙酸含量,始终显著(P<0.05)高于C、G和M组,青贮7d后开始显著(P<0.05)高于P+G和P+M组。青贮第7天P组氨态氮/总氮显著(P<0.05)低于对照组,之后各组氨态氮/总氮均随青贮时间的延长逐渐上升,其中P、P+G和P+M组氨态氮/总氮显著(P<0.05)低于C、G或M组直至青贮结束。本试验结论认为单独添加乳酸菌明显提高了桑叶青贮发酵品质,而组合添加并未进一步得到大的改善。

不同成熟度桑葚果实和叶片的多酚、黄酮和抗氧化性研究(英文)

【目的】明确桑葚果实和叶片的抗氧化活性。【方法】以不同成熟度的红桑葚(Morus rubra)果实和叶子为材料,研究其提取物的多酚、黄酮和抗氧化活性差异。【结果】成熟叶片中的多酚和黄酮含量最高,接下来依次是嫩叶、黑色果和红色果。通过DPPH、FRAP和SRSA方法,测定的抗氧化能力从低到高的顺序依次是黑色果、红色果、嫩叶和成熟叶。清除ABTS自由基的能力从高到低依次是成熟叶、嫩叶、黑色果和红色果。表明在DPPH、FRAP和SRSA分析体系里,提取物中花青素的含量起着主要的抗氧化作用,而在ABTS体系里,抗氧化活性主要与多酚和黄酮含量和种类有关。【结论】桑葚的果实和叶片是很好的天然抗氧化物质,尤其是果实。

盐胁迫对桑树幼苗光合生理及叶绿素荧光特性的影响

试验以黄河流域和西北地区常用的桑树砧木-1年生实生桑树幼苗为试验材料,采用盆栽加盐的方式模拟盐胁迫环境,通过设置1、3、5、7 g.kg-1等4个盐分梯度,以不加NaCl(0 g.kg-1)为对照(CK),研究NaCl胁迫对桑树幼苗光合作用和叶绿素荧光特性的影响。结果表明:1 g.kg-1NaCl处理对桑树幼苗叶片的净光合速率(Pn)没有明显影响;而3、5、7 g.kg-1等NaCl处理则对Pn具有明显的抑制作用,5、7g.kg-1等的NaCl处理的影响显著,造成桑树幼苗Pn急剧降低,部分植株受害严重,甚至死亡。此外,1、3 g.kg-1等NaCl处理对桑树幼苗的气孔导度(Gs)、蒸腾速率(Tr)、水分利用率(WUE)和胞间CO2浓度(Ci)没有明显影响,而5、7 g.kg-1等NaCl处理则显著提高了桑树幼苗的Ci,降低了Gs、Tr和WUE。盐胁迫对桑树幼苗叶片的叶绿素荧光参数具有一定的影响。随NaCl处理浓度增大,初始荧光(Fo)呈下降的趋势,而非光化学荧光淬灭系数(NPQ)则先升后降,但处理之间Fo和NPQ变化差异不明显;1、3 g.kg-1等NaCl处理对桑树幼苗的最大荧光(Fm)、最大光化学效率(Fv/Fm)、潜在光化学效率(Fv/Fo)和PSⅡ有效光化学量子效率(ΦPSⅡ)没有明显影响,而5、7 g.kg-1等NaCl处理则显著降低其Fm、Fv/Fm、Fv/Fo和ΦPSⅡ。

桑叶多糖的含量测定

用蒽酮-硫酸比色法测定了桑叶中多糖的含量。测定波长620nm,多糖换算因子f=3.07;在10～60μg/ml范围内吸收度与被测物含量呈良好的线性关系,r=0.999005;多糖的平均回收率为98.81%,RSD为2.08%(n=5)。测定结果表明,10月份桑叶中多糖含量最高。本法简便、准确、重现性好,可作为桑叶中多糖的含量测定方法。