Identification of key genes regulating the synthesis of quercetin derivatives in Rosa roxburghii through integrated transcriptomics and metabolomics

Rosa roxburghii fruit is rich in flavonoids, but little is known about their biosynthetic pathways. In this study, we employed transcriptomics and metabolomics to study changes related to the flavonoids at five different stages of R. roxburghii fruit development. Flavonoids and the genes related to their biosynthesis were found to undergo significant changes in abundance across different developmental stages, and numerous quercetin derivatives were identified. We found three gene expression modules that were significantly associated with the abundances of the different flavonoids in R. roxburghii and identified three structural UDP-glycosyltransferase genes directly involved in the synthesis of quercetin derivatives within these modules. In addition, we found that RrBEH4, RrLBD1 and RrPIF8could significantly increase the expression of downstream quercetin derivative biosynthesis genes. Taken together,these results provide new insights into the metabolism of flavonoids and the accumulation of quercetin derivatives in R. roxburghii.

Effect of fermented Rosa roxburghii Tratt fruit juice on gut microbiota in a dextran sulfate sodium-induced colitis mouse model

This study mainly investigated the regulatory effect of Rosa roxburghii Tratt fruit juice fermented by Lacticaseibacillus paracasei SR10-1(LAB-RRTJ)on modulating gut microbiota in dextran sulfate sodium(DSS)-induced ulcerative colitis in mice.Compared to control group,DSS induction decreased body weight of mice,indexes of Shannon,Simpson,Chao1 and Faith_pd,and increased disease activity index(DAI)and levels of interleukin 1β(IL-1β),IL-6,tumor necrosis factorα(TNF-α)and interferon-γ(IFN-γ);And this induction also led to an increase in Proteobacteria,Verrucomicrobia and Actinobacteria at phylum level,harmful bacterial species richness at genus level,and relative richness of S.sciuri,Desulfovibrio C21_c20,R.gnavus and Akkermansia muciniphila at species level,and a decrease in Firmicutes at phylum level and relative richness of B.acidifaciens in mice.LAB-RRTJ increased body weight of mice with DSS induced ulcerative colitis(UC)and indexes of Shannon,Simpson,Chao1 and Faith_pd,reduced DAI and the content of four infl ammatory factors and improved gut microbiota imbalance in DSS induced UC mice.Besides,the number of operational taxonomic units(OTUs)increased,α-diversity andβ-diversity were restored and similar to those in mice in the control group after LAB-RRTJ treatment.Compared with the positive drug treatment group,LAB-RRTJ has a better effect on regulating gut microbiota diversity in colitis mice.Correlation analysis showed that infl ammatory factors were positively correlated with harmful bacteria and negatively correlated with beneficial bacteria which commonly found in some colitis mice.Taken together,our study demonstrated that LAB-RRTJ could alleviate DSS-induced colitis in mice through the modulation of infl ammatory cytokines and gut microbiota composition.

Advances in the Study of Anoectochilus Roxburghii Extracts and Prospects for Cosmetic Application Potentials

Cosmetics made from natural ingredients are becoming more and more common because they contain bioactive compounds that provide many health benefits,are more environmentally friendly and sustainable.Anoectochilus roxburghii(AR)is a precious Chinese herb in China,possessing bioactive components including flavonoids,polysaccharides,volatile oils,kinsenoside,etc.Due to its unique bioactivity and high safety,the prospect of development and utilization is very broad.In this paper,the extraction,separation and purification techniques of AR’s flavonoid,polysaccharides,volatile oils and kinsenoside are briefly summarized.Meanwhile,we discusses their conformational relationships in cosmetics with antioxidant,whitening,antibacterial and soothing effect,and looks forward to the study of Anoectochilus roxburghii in the field of cosmetics,with a view to providing references to the development and utilization of this resource in the field of cosmetics.

Mechanism of Rosae Rugosae Flos fl avonoids in the treatment of hyperlipidemia and optimization of extraction process based on network pharmacology

This study aims to identify a natural plant chemical with hypolipidemic effects that can be used to treat high cholesterol without adverse reactions.Through network pharmacology screening,it was found that Rosae Rugosae Flos(RF)flavonoids had potential therapeutic effects on hyperlipidemia and its mechanism of action was discussed.TCMSP and GeneCards databases were used to obtain active ingredients and disease targets.Venn diagrams were drawn to illustrate the findings.The interaction network diagram was created using Cytoscape 3.8.0 software.The PPI protein network was constructed using String.GO and KEGG enrichment analysis was performed using Metascape.The results revealed 2 active flavonoid ingredients and 60 potential targets in RF.The key targets,including CCL2,PPARG,and PPARA,were found to play a role in multiple pathways such as the AGE-RAGE signaling pathway,lipid and atherosclerosis,and cancer pathway in diabetic complications.The solvent extraction method was optimized for efficient flavonoid extraction based on network pharmacology prediction results.This was achieved through a single factor and orthogonal test,resulting in an optimum process with a reflux time of 1.5 h,a solid-liquid ratio of 1:13 g/mL,and an ethanol concentration of 50%.

Exploring the mechanism of Crocus sativus and Rosa rugosa for the treatment of coronary heart disease based on network pharmacology and molecular docking

Coronary atherosclerotic heart disease(CHD)is the main type of cardiovascular disease.The efficacy of Uyghur drug compound Saffron formula in CHD has been clinically proven.However,the underlying mechanism remains unclear.In this study,researchers investigated the active ingredients and mechanism of action of Crocus sativus and Rosa rugosa in the treatment of CHD by network pharmacology and molecular docking techniques,collected target information with the help of TCMSP,GEO,GeneCards,and other databases,constructed protein-protein interaction(PPI)network diagrams by STRING database,performed GO and KEGG pathway enrichment analysis on common targets,and finally molecularly docked the active ingredients with core targets.C.sativus-R.rugosa have a variety of polyphenol compounds,a total of 12 active ingredients,including quercetin and kaempferol,were screened.The first three targets intersected with the core targets of CHD as AKT1,TNF,and IL-1B.Enrichment results of KEGG pathway showed that C.sativus-R.rugosa against CHD involved atherosclerosis pathways.The molecular docking results showed that quercetin and kaempferol were well bound to the core targets,and it was speculated that these components might be the main active ingredients for the treatment of CHD.The potential mechanism of action of C.sativus-R.rugosa for the treatment of coronary heart disease was initially revealed.

Determination of 13 Trace Elements in Anshun Thorn Pear (Rosa roxburghii) and Golden Thorn Pear (Rosa sterilis S.D.Shi) by ICP-MS

[Objectives] This study was conducted to establish an analytical method for the establishment of 13 trace elements in Anshun thorn pear(Rosa roxburghii) and golden thorn pear(Rosa sterilis S. D. Shi). [Methods] Nitric acid was used as the digestion system for microwave digestion. Inductively coupled plasma mass spectrometry(ICP-MS) was used to determine the trace elements in thorn pear and golden thorn pear. [Results] Be, Ti, V, Cr, Mn, Co, Ni, As, Sr, Mo, Cd, Sb and Hg were determined by ICP-MS method in thorn pear and golden thorn pear. The correlation coefficients of the regression equations of the elements were higher than 0.996; the precision RSD was lower than 2.87%; and the recovery ranged from 94.3% to 109.8%. [Conclusions] The method has the advantages of high sensitivity, good accuracy and simultaneous detection of multiple elements, and provides a reference method and theoretical basis for determining trace elements in thorn pear and golden thorn pear and other fruits.

Changes of Endogenous Hormone Contents in Fruit, Seeds and Their Effects on the Fruit Development of Rosa roxburghii

The fruit of cultivar Guinong5 (Rosa roxburghii Tratt.) was used to investigate the regularity of its growth and development, and the changes of endogenous hormone contents during the period of the growth and development. The result showed that contents of GA 1+3, IAA and ZRs in the flower receptacle of young fruit were high and then decreased, contents of GA 1+3and IAA in seeds increased with its development until maturity. The contents of ZRs and ABA in the flower receptacle of young fruits and seeds were high, and then had a tendency of descent with the development of fruits. The contents of GA 1+3, IAA, ZRs and ABA in flower receptacle of young fruit with normal fertilization were much higher than those of in non-fertilization fruits. In the flower receptacle of malformed fruits, the contents of GA 1+3, IAA and ZRs in normally developing flower receptacle were significantly higher than those in malformed fruits. The growth and development of fruits depended largely on the seeds, development because the seeds in the fruits with non-fertilization failed to be formed or even formed but irreproducible, which would lead to the decrease of GA 1+3, IAA contents and the abnormal development of fruits. Therefore the fruits deformed and dropped inevitably.

Chloroplast DNA-based genetic variation of Rosa roxburghii in Southwest China:Phylogeography and conservation implications

Rosa roxburghii Tratt.is a well-known commercial horticultural crop in China with nutritional and medicinal value.Wild germplasms of this species are mainly distributed in Southwest China but the population is decreasing due to continuous exploitation,habitat destruction,and fragmentation.Therefore,assessing the genetic diversity and phylogeography is essential for efficient conservation.Herein,two chloroplast intergenic spacers(trnL-trnF and accD-psaI)were investigated in 255 individuals from 29 R.roxburghii populations and 18 haplotypes(H1–H18)were identified.High levels of haplotype diversity(Hd=0.829)and nucleotide diversity(π=1.3×10^(−3))were detected in these populations.Also,the genetic variation representing 86.4%of the total variation was detected by an analysis of molecular variance.A significant correlation was established between genetic divergence and geographic distance by the Mantel test(r=0.204,P=0.04,9999 permutations),suggesting the isolation-by-distance model.A significantly higher Nst than Gst(Nst=0.257,Gst=0.136,P<0.05)indicated the phylogeographic structure of R.roxburghii.Further phylogeographic analysis revealed rapid range expansion in the population,probably between 647073 and 217848 years ago.The primary processes shaping the genetic patterns of the R.roxburghii populations included restricted gene flow with isolation distance within clades 1-8,2-3,and overall,contiguous expansion within clades 1-3 and 3-2,past fragmentation,and/or long-distance colonization within clades 1-9 and 2-2.Conservation priority should be given to the core populations GZ,FQ,DF,DS,xy,AL,LC,PB,and XY in the Yunnan-Guizhou Plateau,NZ and MX in the Qingling-Bashan mountains,and MN in the Hengduan mountains,where an in situ preservation and management strategy should be applied.

Structural characteristics,anticoagulant and antithrombotic mechanism of a novel polysaccharide from Rosa Chinensis Flos

This is the first report on a polysaccharide(RCJ2-Ib)isolated from Rosa Chinensis Flos.RCJ2-Ib was obtained through the extraction with water,precipitation with ethanol,separation with DEAE-52 column and purification with DEAE-Sepharose Fast Flow column and Sephadex G100 column.GC,FT-IR and NMR analyses revealed that RCJ2-Ib(3.3 k Da)was a 1,4-linked polymannuronic acid containing substantialβ-Danomers units.The anticoagulant effect of RCJ2-Ib evaluated by using rabbit ear venous blood and an acute blood stasis rat model showed that RCJ2-Ib had obvious anticoagulant activity in regulating endogenous and exogenous coagulation pathways and reducing serum thromboxane B2 and endothelin-1.In addition,RCJ2-Ib could also increase the number of Lactobacillus and Escherichia coli.As a result,RCJ2-Ib has the potential to inhibit thrombosis and maintain the intestinal environment.

Polysaccharide extract from Rosa laevigata fruit attenuates inflammatory obesity by targeting redox balance and gut interface in high-fat diet-fed rats

Low-molecular-weight polysaccharides(RLPs)extracted from Rosa laevigata fruits showed multiple biofunctions in Asia.This study aimed to investigate its anti-inflammatory obesity effect in high-fat dietfed rats and further elucidated the underlying molecular mechanism by multi-omics methods.The results showed that RLPs administration had significantly restored immune organ indexes and reduced body weight gain.RNA-seq revealed that the effect of RLPs was partially attributed to its regulation on PPARs signaling by increasing the expressions of Scd,Acox3 and Hmgcs2,and on other redox-related pathways by decreasing the expressions of Cyp2 e1,Il1-r1 and Lbp.Moreover,16 S rRNA sequencing coupled with metagenome sequencing showed that RLPs had significantly reduced the ratio of Firmicutes/Bacteroidetes from 8.01 to2.37,and significantly increased the relative abundances of Alistipes,Prevotella,and Akkermansia from 0.36%,1.10%and 2.61%to 0.65%,2.37%and 4.42%,respectively.Spearman correlation analysis result indicated that the abundances of Lachnospiraceae,Prevotella and Bacteroidales were significantly negatively correlated with obesity phenotype,liver function and inflammatory factors.These results revealed that RLPs exerted significant anti-inflammatory obesity property partially via regulation on gut microbiota interface and the redox balance.Therefore,RLPs could be a promising functional food resource with the potential for redox imb alance-related diseases chemoprevention.

Exploring the Protective Effect of the Ethanolic Extract of Rosa laevigata Michx.Fruit on Rats with Mesangial Proliferative Glomerulonephritis Based on NLRP3 Inflammasome Pathway

Objective:To investigate the effect of the ethanolic extract of Rosa laevigata Michx.fruit on rats with mesangial proliferative glomerulonephritis based on the NLRP3 inflammasome pathway.Methods:Thirty Wistar rats were divided into three groups,a blank control group,a diabetic nephropathy(DN)model group,and an ethanolic extract intervention group,according to the random number table method,with 10 rats in each group.One day before the experiment,basic feeding was initiated for all the rats;the changes in activity and weight of each group of rats were observed and recorded after 7 d,and a rat model of renal function injury was established after 1 d.Results:Compared with the control group,the model group had significantly higher kidney/body ratio,24 h urine protein,serum creatinine(SCr),blood urea nitrogen(BUN),glomerular mesangial cell(GMC)count,and extracellular matrix(ECM)positive area ratio(P<0.05);the same indicators were significantly lower in the intervention group than in the model group(P<0.05).The NLRP3 inflammasome pathway in renal intrinsic cells was activated in the intervention group.The overactivation of NLRP3 inflammasome is known to promote interleukin(IL)-1βrelease,which was inhibited in the intervention group.Conclusion:The ethanolic extract of Rosa laevigata Michx.fruit has a protective effect on renal intrinsic cells and may be related to NLRP3 inflammasome pathway,suggesting that the fruit of Rosa laevigata Michx.has a potential role in protecting renal intrinsic cells from inflammatory damage.NLRP3 inflammasomes are involved in the development of various chronic inflammatory diseases,such as acute and chronic glomerulonephritis and renal fibrosis.

金樱子叶衍生碳点的制备及其对金樱子不定芽的影响

为了探讨碳点对植物组织培养的影响,本论文以金樱子叶为碳源,采用一步水热法制备荧光碳点(JCDs),再以金樱子茎段为外植体建立再生体系,研究J-CDs对金樱子不定芽生长的影响。结果表明,J-CDs生物相溶性好,在pH值2-8范围内保持稳定,适用于植物组织培养。添加J-CDs可以促进金樱子不定芽生长,实验组金樱子不定芽株高比对照组高3-4倍,植株健壮,枝叶伸展,生长良好。当J-CDs浓度为0.9mg·mL^(-1)时,金樱子不定芽叶绿素总含量和可溶性蛋白含量达到最大值,SOD和POD酶活性最大,分别比对照组增加了56.25%和41.82%。本研究利用金樱子生物质制备荧光CDs,促进金樱子不定芽生长,为植物繁育提供了新方法。

无籽刺梨及其近缘种叶绿体基因组序列比较分析

【目的】探讨无籽刺梨及其近缘种之间的系统发育关系,为蔷薇属植物后期分子鉴定和群体遗传研究奠定基础。【方法】从NCBI数据库下载了6种植物的叶绿体基因组序列,包括无籽刺梨和其近缘种。利用生物信息学方法对这些基因组序列进行了研究,包括基因组结构、重复序列、高变区序列以及基于叶绿体全基因组序列的系统发育关系。【结果】6种植物的叶绿体基因组呈环状四分体结构,其长度为156561~156749 bp,平均GC含量均为37.2%,且6种植物基因组的反向重复(inverted repeat,IR)区未表现出明显的扩张和收缩。在对蔷薇属植物叶绿体基因组序列进行比较分析时,筛选出了7个高变区序列,包括trnK-trnQ、psbM-trnY、ycf3-rps4、rps4-trnL、psbE-petG、rpl16 intron和ycf1。这些序列可作为候选标记,用于进一步研究蔷薇属植物的系统发育。同时,利用叶绿体全基因组序列重建了蔷薇属植物的系统发育树。结果表明,无籽刺梨和刺梨是独立的2个种类,其中无籽刺梨与贵州缫丝花有较近的亲缘关系,而刺梨与单瓣缫丝花有较近的亲缘关系。【结论】无籽刺梨及其近缘种之间叶绿体基因组结构高度相似,单拷贝区核苷酸多样性高于重复区。

干旱胁迫条件下朱槿叶绿素荧光特性

以朱槿为试验材料,研究了干旱胁迫及复水对朱槿叶片叶绿素荧光参数的影响。结果表明:朱槿在经受25 d自然干旱胁迫后,除Fv/Fm值显著降低外,Y(Ⅱ)、qP、NPQ、ETR等值均有所上升。复水1 d后,Fv/Fm值有止降回升的趋势,Y(Ⅱ)、qP、NPQ、ETR等参数则恢复到对照水平。利用直角双曲线修正模型拟合的快速光曲线结果表明,中度干旱胁迫提高了朱槿光化学反应的启动能力,在弱光条件下具有最高的光能利用效率。当光强超过190μmol/(m^(2)·s)时,CK和复水1 d的适应能力更强,具有最大适应光强变化的能力和光合活性。研究综合认为,朱槿在干旱胁迫下具有良好的自身调节能力,具有较强的光合系统损伤修复能力,表现出极强的抗干旱胁迫能力,可在较干旱地区栽培应用。

盐胁迫下外源褪黑素和丛枝菌根真菌对月季幼苗生长生理特性的影响

【目的】盐胁迫易导致月季生长发育不良、观赏品质下降,严重影响其在高盐环境或沿海地区室外绿化应用,探究施用外源褪黑素(MT)和接种丛枝菌根真菌(AMF)对其幼苗生长、叶绿素荧光参数以及激素代谢的调控作用,解析它们促进月季适应盐胁迫的生理生化机制,对于增强月季抗盐性,扩大月季应用范围具有重要意义。【方法】以月季品种‘月月红’幼苗为试验材料,采用室内盆栽试验,设置对照(CK)、100 mol/L NaCl胁迫、根际施用MT、根际接种AMF幼套近明球囊霉(Claroideoglomus etunicatum)及其组合等8个处理,考察各处理对月季幼苗生长、叶绿素荧光参数、激素代谢及抗氧化系统的影响。【结果】(1)施用MT可以促进AMF对月季幼苗根系的侵染,提高侵染率、丛枝着生率、泡囊数和侵入点数;(2)月季幼苗株高、茎粗以及生物量等在盐胁迫下显著下降,在MT或AMF处理下均不同程度增加,而AMF+MT处理下株高、茎粗无显著变化,地上部干重、地下部干重分别显著增加24.1%和37.0%;(3)月季幼苗叶绿素含量在盐胁迫下显著下降,叶绿素荧光参数也降低,MT或AMF处理能提高盐胁迫月季幼苗叶绿素含量以及叶绿素荧光参数,AMF+MT处理则使叶绿素总量、叶绿素a/b分别增加46.2%和67.2%,PSⅡ最大光化学效率(F_(v)/F_(m))、潜在活性(F_(v)/F_(o))、实际光化学效率(ΦPSⅡ)、有效光化学量子效率(Fv'/Fm')、光化学淬灭系数(qP)分别增加4.9%、51.0%、175.0%、168.7%和92.5%,而NPQ下降42.7%;(4)在盐胁迫下,月季叶片中玉米素(ZT)、赤霉素(GA)、生长素(IAA)含量下降,而脱落酸(ABA)含量增加,MT或AMF处理有利于盐胁迫下ZT、GA、IAA含量的提高以及ABA含量的下降,AMF+MT处理后ZT、GA、IAA分别增加146.9%、116.9%、35.7%,ABA下降21.1%;(5)在盐胁迫下,抗氧化酶SOD、CAT活性增强,超氧阴离子(O_(2)^(-·))产生速率和H_(2)O_(2)累积大量增加,MT或AMF处理有助于增加抗氧化酶活性并减少O_(2)^(-·)产生速率和H_(2)O_(2)含量,而AMF+MT处理能够进一步激活SOD、CAT活性,降低O_(2)^(-·)产生速率和H_(2)O_(2)累积。【结论】接种AMF、添加MT或者AMF+MT处理均可以提高盐胁迫下月季幼苗叶绿素含量,保护叶绿素荧光系统,维持植物内源激素的平衡,激活SOD、CAT等抗氧化酶活性以及降低脂质过氧化和H_(2)O_(2)累积,以减轻盐胁迫对月季幼苗的伤害,促进月季生长,并以AMF+MT处理增强月季幼苗抗盐性的效果更佳。

体外产气法评价刺梨果渣对肉羊瘤胃体外发酵参数的影响

研究旨在利用体外产气法评价不同水平刺梨果渣的肉羊瘤胃体外发酵参数,为开发利用刺梨果渣饲料资源奠定基础。以4只成年山羊作为瘤胃液供体羊,体外发酵底物为动物饲养试验中肉羊采食的3组饲粮(对照组:不含刺梨果渣;处理1组:含12%刺梨果渣;处理2组:含24%刺梨果渣),测定产气量、发酵参数、纤维素酶活性。结果显示:处理1组6 h累计产气量(GP_(6 h))显著高于对照组(P<0.05),3组间其余时间点产气量差异不显著(P>0.05)。处理1组总挥发性脂肪酸、乙酸含量具有高于对照组、处理2组的趋势(P=0.08);3组间其余发酵参数[氨态氮(NH_(3)-N)、干物质降解率(DMD)和有机物降解率(OMD)]无显著差异(P>0.05)。3组间瘤胃纤维素酶(纤维二糖酶、羧甲基纤维素酶、木聚糖酶)活性不受刺梨果渣水平的影响,差异不显著(P>0.05)。由此可见,刺梨果渣对肉羊瘤胃体外发酵没有负面影响,可作为肉羊饲料使用,适量水平(12%)的刺梨果渣可提高产气量,促进瘤胃发酵,但仍需结合生产实际情况考虑其对肉羊生产性能的影响。

刺梨复合果茶的制备及品质研究

以刺梨、柠檬、金桔、赤藓糖醇为原料,以维生素C(VC)含量和感官评分为评价指标,进行刺梨复合果茶的制备工艺及品质研究。各原料经干燥工艺处理后,采用混料设计中的单纯形格子设计确定刺梨复合果茶的最佳配方,并对刺梨复合果茶的感官指标、理化指标以及抗氧化能力进行分析。结果表明,刺梨复合果茶的最佳配方是:刺梨70%、柠檬5%、金桔5%、赤藓糖醇20%,该果茶产品的维生素C含量为7.09 g/100 g、总酸含量为80.62 g/kg、p H为3.46,DPPH自由基清除率为98.43%、羟基自由基清除率为13.71%。刺梨复合果茶的维生素C含量较高、抗氧化能力较强,具有较好的品质。

非生物胁迫对月季生长发育影响的研究进展

从温度、光照、水分、盐及重金属5个非生物胁迫方面入手,对月季应答非生物胁迫的形态及生理生化变化、分子调控的研究现状进行综述,阐述非生物胁迫对月季生长发育影响,为深入阐释月季应答非生物胁迫的调控机制提供参考,也为高抗月季品种的培育和应用提供理论依据。提出相关研究应利用组学方法和先进的生物技术多维度解析月季应答非生物胁迫的分子调控网络,挖掘非生物胁迫应答关键基因,通过转基因技术培育抗性强的月季优势品种。

岷江干旱河谷黄蔷薇(Rosa hugonis)生长与繁殖特征及其空间差异

对乡土植物生长繁殖特征的认识是制定合理的植被恢复及管理措施的基础和依据。通过大面积的野外踏查和样方调查,分析了岷江干旱河谷乡土灌木-黄蔷薇(Rosa hugonis)的分布、生长繁殖特征及空间差异。发现:(1)黄蔷薇主要分布于岷江干旱河谷的茂县段,其植株株高、基径、年龄、丛冠幅、丛的萌生数、丛干重、丛生物量和密度等生长特征存在明显空间差异,除丛萌生数和密度之外海拔对其他各参数都有较大的影响,这些参数的值在高海拔地段大于低海拔地段;(2)黄蔷薇在干旱河谷丛平均萌生数为6.48±0.97株/丛,丛的萌生能力较强,且其受砍伐后具有很强的再生能力;萌生株年龄结构大致为金字塔型,最大植株年龄为25 a;(3)干旱河谷黄蔷薇的结实量较大,平均值为(404.96±106.91)果/丛,结实特征表现出明显的空间差异性;(4)各生长与结实参数关系密切,影响结实量的最主要的生长因素是冠幅和丛干重。研究结果表明:黄蔷薇适应干旱河谷的环境条件,具有较广泛的分布,生长和和繁殖状况良好,是可供选择的干旱河谷恢复物种。

刺梨果醋发酵过程中理化特性和风味特征的变化

为探究刺梨果醋发酵过程中成分变化,本文以刺梨为原料,采用全液态发酵技术,经酒精发酵和醋酸发酵制备果醋,动态监测发酵过程中的理化特性,并采用固相微萃取-气相色谱-质谱联用技术(Headspace solid-phase microextraction-gaschromatography-mass spectrometry,HS-SPME-GC-MS)和气味活性值(Odoractivityvalue,OAV)分析挥发性风味成分。结果表明,随着发酵时间的进行,可溶性固形物、pH、总糖及还原糖均呈下降趋势,而总酸和V_(C)含量持续增加,由原汁到醋酸发酵结束分别从1.86 g/100 mL和956.82 mg/100 mL增加至6.79 g/100 mL和1275.88 mg/100 mL。有机酸的含量不断变化,草酸、奎宁酸、丙酮酸、抗坏血酸、乳酸、乙酸及富马酸呈现不同程度的显著增加(P<0.05),而甲酸、柠檬酸、马来酸和琥珀酸含量变化小。共检测到92种挥发性物质,结合OAV分析,10种挥发性物质被确定为刺梨果醋中OAV≥1的关键香气物质,即壬醛、乙醛、异丁酸乙酯、丁酸乙酯、2-甲基丁酸乙酯、乙醇、异戊醇、叶醇、芳樟醇及苯乙醇。其中,丁酸乙酯和叶醇对刺梨果醋香气贡献最大,是刺梨果醋具有青草香、青苹果香的特征风味物质。研究结果为有效控制发酵条件、揭示发酵刺梨果醋的理化特性和风味特征,形成刺梨果醋品质评价方法、制定质量标准提供理论基础和实践指导。