Helianthus tuberosus(Jerusalem artichoke) tubers improve glucose tolerance and hepatic lipid profile in rats fed a high-fat diet

Objective:To analyze the effects of feeding Helianthus tuberosus(HT) tubers on glucose tolerance and lipid profile in rats fed a high-fat diet(HFD). Methods:A normal HFD or HFD including 10 w/w% HT tubers(HFD + HT) was fed to F334/Jcl rats. After 10 weeks,organ weights,glucose tolerance,and lipid profile were analyzed. Results:The body weight,liver weight,and epidermal fat content in the HFD group were higher than those of the normal group,and similar to those of the HFD + HT group. The oral glucose tolerance test at 10 weeks revealed that the blood glucose level 30 minutes after beginning the test in the HFD + HT group was significantly lower than that in the HFD group. Liver triglyceride and total cholesterol levels in the HFD + HT group were significantly lower than those in the HFD group. Fecal triglyceride and total cholesterol levels in the HFD + HT group were higher than those in the HFD group. Histological analyses revealed that fat and glycogen accumulation increased in the HFD group,but decreased in the HFD + HT group. Conclusions:These results indicate that HT tubers have anti-fatty liver effects based on improvements in glucose tolerance and the hepatic lipid profile.

An Analysis on Leaf Traits of 22 Helianthus tuberosus Germplasm Resources Introduced from Abroad

Atomic absorption spectrophotometry,sulfuric acid and potassium dichromate oxidation method and ultraviolet spectrophotometry,were used to determine mineral elements,fiber,the content of chlorogenic acid and flavones in leaves of 24 Helianthus tuberosus Linn.resources,and the characteristics of the leaf introduced from abroad were evaluated.The results showed that the highest water content of 22 species was F12(27.58%),and the lowest was F16(19.02%).The difference in mean water content between the species from Denmark and France was small,but it was lower than that of Qingyu 3 and Qingyu 4.There were 3 orbicular leaves,1 long oval-shaped leaf and 18 oval leaves.The highest K content in the leaves was F19(30.62 mg/g),which was 2.5 times than Qingyu 3.The highest Mg content was D8(14.17 mg/g).The Fe content hadlittledifference,ranging from 0.09 mg/g to 0.19 mg/g.The highest Ca content was D8(26.87 mg/g).The highest level of chlorogenic acid and flavones was F7,2.55%and 1.24 g/100 g respectively.The highest fiber content was F9(16.7%),and the lowest was F19(7.36%).Through the analysis of the main component and the clustering analysis,when the genetic distance was 0.65,the 24 resources can be divided into three major categories.The first category of leaves were mainly oval and orbicular;the second category of leaves were long oval-shaped;the third category of leaves were oval.There was a difference between the various indexes in the leaf of different kinds of H.tuberosus Linn.resources.Finally,F19,D8,F9,F7,D14 and D11,6 specific species(F19,D8,F9,F7,D14 and D11)were screened out for further studies in the future.

Nanoparticles induce the biosynthesis and activity of the new possible therapeutic proteinase source,Talaromyces purpureogenus KJ584844

The need for the bacterial proteinase is rapidly growing,urging to catch a lowcost medium for the microbial fermentation,nanoparticles can play a vital role in this respect.The proteinase of Talaromyces purpureogenus was produced on the tubers of Helianthus tuberosus that also operated as solid support for the fermentation process.The interface amongst nitrogen sources(NH_(4)Cl and yeast extract)was investigated,applying the statistical modeling of central composite design under solid-state fermentation.The optimum medium for proteinase secretion was stimulated by 979.82 mg NH_(4)Cl and 437.68 mg yeast extract per 100 g substrate,yielding 108.15 U/g tubers.Using Plackett-Burman experimental design,the nanoparticles Co,Ni and Fe were assessed as inducers for proteinase stimulants.Co nanoparticles(5 ppm)were the greatest in both proteinase production by the fungus as well as an inducer of the proteolysis process by the enzyme when using faba bean straw as a proteinaceous substrate in the reaction mixture,liberating the extreme quantity of amino acids,compared with the lack of the nanoparticles.The findings suggest the incorporation of Co nanoparticles in both the proteinase fabrication process and during the degradation of proteinaceous materials induce proteinase catalyst.This approach could be extended to modulate the productivity and activity of similar biomolecules.

基于表型数据的菊芋核心种质初步构建

为更好地保存、研究和利用现有菊芋种质资源,本研究以250份种质材料的19个表型性状数据为基础,采用逐步系统聚类并优化聚类和取样方法,初步构建遗传冗余少、代表性强的菊芋核心种质。结果表明,在25%取样比例下多种系统聚类方法抽取的核心种质中,以最短距离法(C4)和优先取样法(S3)组合的C4S3方法所抽取的核心种质评价参数优于其他方法,对原种质的代表性最强。在C4S3法下优化取样比例,结果显示最合适的取样比例为20%,所抽取的核心种质C4S3-20用较少的材料获得了较高的遗传代表性。在C4S3-20方法下继续进行分组取样,评价参数表明分组取样效果不如整体取样,因而不予采纳。主成分分析显示C4S3-20保留了原种质的主成分,去掉了原种质的遗传冗余。最终获得了菊芋核心种质C4S3-20,包括50份材料,其与原种质的性状均值差异百分率为0%,方差差异百分率63.63%,极差符合率为100%,变异系数变化率为131.38%,表型保留比例为96.15%;Shannon多样性指数为1.595。本研究发现该核心种质很好地代表了原种质的遗传多样性,在一定程度上为菊芋资源的有效利用奠定了基础。

菊芋果聚糖合成关键基因1-SST克隆及序列分析

果聚糖是菊芋的主要贮藏物质,其代谢与产量形成和逆境适应性密切相关。为了解菊芋果聚糖合成代谢的机制,本研究以‘青芋1号’为研究对象,利用同源克隆方法,对果聚糖合成关键基因1-SST克隆及序列分析。结果表明,1-SST基因全长为3 925 bp,CDS大小为1 890 bp,由5个内含子和6个外显子组成。经生物信息学分析,预测1-SST蛋白分子量70 934.40 Da,等电点5.10,有两个属于糖基水解酶32家族的保守区,属于亲水性蛋白,以延伸结构(24.48%)和无规则卷曲(56.76%)为主要二级结构,在质膜外行使功能。系统进化分析表明,菊芋1-SST基因与向日葵遗传距离最近,与龙舌兰等不同科不同属的植物进化距离较远。本研究基于对菊芋中调控果聚糖合成代谢1-SST基因的克隆与生物信息学分析,为高等植物果聚糖代谢途径研究奠定一定的理论基础。

干旱胁迫下菊芋果聚糖代谢生理响应特征

菊芋(Helianthus tuberosus L.)以果聚糖作为主要储藏物质,果聚糖有可能在适应干旱胁迫的生理调控中起着重要作用,其干旱条件下响应机制有待进一步研究。本实验以敏感型‘青芋1号’和抗旱型‘青芋3号’为材料,采用人工控水的方法进行干旱胁迫,控水后于不同时期取样并测定植株果聚糖含量及聚合度、果聚糖代谢相关酶活性等生理指标。结果显示:菊芋幼苗在干旱胁迫后,敏感型品种游离糖含量变化明显且处理组果聚糖含量低于对照组,而抗旱型品种的对照组和处理组的果聚糖含量在胁迫前期表现相反,后期同步升高。2个品种菊芋叶片的果聚糖合成酶活性均表现为处理组高于对照组,且抗旱型‘青芋3号’更高,胁迫前期2 d时SST活性达2801.18 kat,后期10 d时IVN、FEH活性分别达到7540.34 kat、7332.36 kat,说明菊芋受到胁迫后,叶片中果聚糖合成酶活性迅速提高,以快速积累果聚糖并增加果聚糖的聚合度,同时向贮存器官快速转运,增强植物抗旱能力;随着胁迫程度的加深,植株通过水解作用将贮存的果聚糖解链,释放出游离单糖以提升渗透调节能力。