Population genetic insights into the conservation of common walnut(Juglans regia)in Central Asia

The common walnut(Juglans regia)is one of the most economically important nut trees cultivated worldwide.Despite its importance,no comprehensive evaluation of walnut tree population genetics has been undertaken across the range where it originated,Central Asia.In this study,we investigated the genetic diversity and population structure of 1082 individuals from 46 populations across Central Asia.We found moderate genetic diversity of J.regia across Central Asia,with 46 populations clustered into three groups with a weak relationship between genetic and geographic distance.Our findings reveal that the western Himalaya might be the core region of common walnut genetic diversity in Central Asia and that,except for two populations in Gongliu Wild Walnut Valley,humans might have introduced walnut populations to Xinjiang,China.The observed distribution of the genetic landscape has probably been affected by historical climate fluctuation,breeding system,and prolonged anthropogenic activity.We propose the conservation of the core genetic diversity resources in the western Himalaya and pay special attention to populations from Gongliu in Xinjiang.These findings enhance our understanding of the genetic variation throughout the distribution range of J.regia in Central Asia,which will provide a key prerequisite for evidence-based conservation and management.

Antioxidant,antimicrobial,and α-glucosidase inhibitory activities of saponin extracts from walnut(Juglans regia L.) leaves

Objective:To investigate the relationship between triterpenoid saponin content and antioxidant,antimicrobial,and α-glucosidase inhibitory activities of 70%ethanolic,butanolic,aqueous,supernate and precipitate extracts of Juglans regia leaves.Methods:Triterpenoid saponins of different Juglans regia leaf extracts were measured by the vanillin method.Antioxidant activity was evaluated against DPPH and ABTS free radicals.We also assessed α-glucosidase inhibitory and antimicrobial activities of the leaf extracts.Pearson’s correlation coefficient was evaluated to determine the correlation between the saponin content and biological activities.Results:The butanolic extract was most effective against DPPH with an IC50of 6.63μg/mL,while the aqueous extract showed the highest scavenging activity against ABTS free radical with an IC50of 42.27μg/mL.Pearson’s correlation analysis indicated a strong negative correlation (r=-0.956) between DPPH radical scavenging activity (IC50) and the saponin content in the samples examined.In addition,the aqueous extract showed the best α-glucosidase inhibitory activity compared with other extracts.All the extracts had fair antibacterial activity against Bacillus subtilis,Escherichia coli,and Klebsiella pneumoniae except for the aqueous extract.Conclusions:Juglans regia extracts show potent antioxidant,antimicrobial,and α-glucosidase inhibitory activities.There is a correlation between saponin levels in Juglans regia leaf extracts and the studied activities.However,additional research is required to establish these relationships by identifying the specific saponin molecules responsible for these activities and elucidating their mechanisms of action.

Two new diarylheptanoids from the pericarps of Juglans regia L.

Two new cyclic diarylheptanoids juglanin A （1） and juglanin B （2） were isolated from the pericarps of Juglans regia L. Their structures were elucidated by various spectroscopic methods including 2D NMR techniques （COSY, HMQC, HMBC, NOESY） and HR-ESIMS.

In vitro antibacterial and free radical scavenging activity of green hull of Juglans regia

Abstract Antioxidant supplements from plants are vital to count the oxidative damage in cells. We assessed the antioxidants and antibacterial activity of green hull of Juglans regia in this study. According to our results the maximum antibacterial activity was observed in ethanolic extract when compared to other extract. So, the ethanolic extract was studied for antioxidant activity which exhibited high antiradical activity against DPPH, hydroxyl, and nitric oxide radicals. In conclusion, green hull of J. regia showed strong reducing power activity and total antioxidant capacity. The results justify the therapeutic application of plant in the indigenous system of medicine.

Anti-diabetes Agents——I:Tetralone Derivative from Juglans regia

A new compound, 4-hydroxy-a-tetralone-4-O-b-D-[6-O-(3,4,5-trihydroxybenzoyl) glucopyranoside (1), together with a known compound, 4-hydroxy-a-tetralone (2), has been isolated from the roots of Juglans regia. 2 showed moderate bioactivity against protein tyrosine phosphatase 1B (PTP1B).

Two new glucosides from the pellicle of the walnut (Juglans regia)

A newα-tetralonyl glucoside,6'-O-acetyl-juglanoside E(1),and a new dihydrophaseic acid glucoside,dihydrophaseic acid 1-O-(6-O-acetyl)-glucopyranoside(2),together with two known ones,juglanoside E(3)and dihydrophaseic acid(4),were isolated from the pellicle of the walnut(Juglans regia).The structures of the new compounds were elucidated by comprehensive spectroscopic analysis,including IR,HRESIMS,1D and 2D NMR data.

Gene flow among wild and cultivated common walnut(Juglans regia)trees in the Qinling Mountains revealed by microsatellite markers

Patterns of gene flow and gene introgres sion can be used to assess the risk of genetic pollution of wild forest trees from widespread cultivated trees.A comprehensive understanding of the genetic relationships and levels of gene flow among wild and cultivated common walnut(Juglans regia)has become an urgent issue.Using twelve microsatellite markers,we investigated the genetic diversity and gene flow between cultivated and wild trees of J.regia in the Qinling Mountains,China.A high level of genetic variation was detected in both cultivated and wild trees.The mean number of alleles per locus was 17.5.Observed heterozygosity(HO)and expected heterozygosity(HE)were 0.777 and 0.800,respectively.Pollination of mother trees was not by nearest neighbors,and a paternity of 60.7%of offspring evaluated could not be assigned to a local,sampled tree.Pollen flow from cultivated trees to wild trees was infrequent(5.4%),and selfing rates ranged from zero to 25.0%.Male parents were located from 0 to 1005 m from their female partners,with an average pollination distance of 285.1 m.These results are discussed in light of the cultivated species’diversity,outlining the frequent spontaneous genetic contributions from the wild to the cultivated compartment.In addition,the pollen flow parameters provide useful information about the dynamics of pollen movement within J.regia populations.

Antiglycation and antioxidation properties of juglans regia and calendula officinalis:possible role in reducing diabetic complications and slowing down ageing

OBJECTIVE:Accumulation of advanced glycation end products(AGEs) in the body due to the non-enzymatic glycation of proteins and oxidation is associated with aging and diabetes mellitus.In this study we wanted to investigate the antiglycation and antioxidation potential of two medicinal plants:Juglans regia and Calendula officinalis.METHODS:In-vitro investigation was carried out to discover the antiglycation and antioxidation potential of J.regia and C.officinalis.Using an Ultraviolet Double-beam Spectrophotometer,we evaluated the antiglycation property of the crude methanolic extracts of J.regia and C.officinalis by assessing their ability to inhibit the Maillard reaction.Employing the same instrument we also measured the antioxidation potential of these plant extracts using the nitric oxide(NO) free radical-scavenging assay.RESULTS:J.regia had greater antiglycation ability,with a minimum inhibitory concentration(MIC 50) of 28 μg/mL as compared with that of C.officinalis(270 μg/mL).C.officinalis had greater antioxidation potential(26.10,22.07 and 16.06% at 0.5 mg,0.25 mg and 0.125 mg,respectively,as compared with 18.15,16.50 and 16.06% of J.regia,respectively).CONCLUSION:J.regia and C.officinalis inhibited the Maillard reaction and prevented oxidation in-vitro.Hence,the extracts of these plants could have therapeutic uses in curbing chronic diabetic complications and slowing down aging.

Key chemical composition of walnut(Juglans regia.L)Oils generated with different processing methods and their cholesterol-lowering effects in HepG2 cells

We systematically evaluated fatty acids and triacylglycerol composition,as well as tocopherol,phytosterol,and phenolics,in walnut oil and compared the cholesterol-lowering effects of oil processed with different methods(cold pressing,roast-pressing,hexane extraction,subcritical butane extraction,and supercritical CO_(2) extraction).The different methods did not affect the lipid composition of walnut oil.The tocopherol(41.11 mg/100 g)and total phenolic content(TPC,4.26 mg/100 g)of roast-pressed walnut oil and the phytosterol contents of subcritical butane-extracted walnut oil(106.51 mg/100 g)were higher than those of other tested oils.Walnut oil significantly decreased cholesterol synthesis by downregulating the expression of HMGCR,SREBP-2,and CYP51 genes,and increased cholesterol efflux by upregulating the expression of ABCG1,thus significantly reducing total cholesterol and triacylglycerol.Phytosterols and TPC in walnut oil were responsible for lowering cholesterol;the optimal concentration of phytosterols was 10μg/mL,and that of TPC was 12.5×10^(-3)μg/mL.Through process optimization,a new processing method for walnut oil based on biological evaluation was preliminarily established.

Phytochemical profile and biological activity of Juglans regia

Juglans regia Linn. （Juglandaceae）, popularly known as English or Persian walnut, is a valuable medicinal plant with a potency to cure various diseases in traditional medicine, Since ancient time, different local ethnic groups have used various part of J. regia for a wide array of ailments including helminthiasis, diarrhea, sinusitis, stomach ache, arthritis, asthma, eczema, scrofula, skin disorders, diabetes mellitus, anorexia, thyroid dysfunction, cancer and infectious diseases. Biological activities of J. regia have been reported in several peer review journals and scientific attention is increasing. The present review attempts to provide comprehensive information on plant description, ethnobotanical use, toxicity, phytochemical profile, pharmacology, clinical studies and current research prospective of the J. regia. Currently, there is an immense interest on isolation/identification of active constituents from walnut and screening those active compounds for pharmacological activities. In addition, researchers are performing clinical trials as well as screening various solvent extracts or fractions of J. regia in several animal diseases models to identify promising therapeutic benefits. In the present work, we review the latest information based on published scientific investigations of J. regia.

陕西省核桃黑斑病新病原的鉴定及室内药剂筛选

分离田间红仁核桃(Juglans regia ‘Robert Livermore’)病叶上的黑斑病病原细菌,通过科赫氏试验明确致病菌,并通过病原菌生化试验以及分子生物学技术明确病原菌的分类学地位。结果表明,从红仁核桃的田间核桃病叶中分离到23株菌落形态一致的细菌菌株,从中随机选取菌株进行科赫氏回接试验能引起红仁核桃叶片发病,通过生理生化表型试验,结合基于16S rDNA、gyrB、rpoD基因序列的多位点序列分析,将该病原鉴定为扁桃假单胞菌(Pseudomonas amygdali)。随后对12种药剂进行室内毒力测定,筛选出的6种药剂对该病原菌具有明显抑制作用。其中,四霉素抑菌效果最好,EC50为50.353 4 μg/mL,其他药剂抑菌效果表现为中生菌素>春雷霉素>噻菌酮>噻唑锌>氢氧化铜。

基于网络药理学及分子对接技术分析核桃治疗高尿酸血症的作用机制

基于网络药理学方法及分子对接技术分析核桃(Juglans regia L.)治疗高尿酸血症(Hyperuricemia,HUA)的作用机制,利用中药系统药理数据库和分析平台(Traditional Chinese medicine systems pharmacology database and analysis platform,TCMSP)预测核桃活性成分的作用靶点,运用OMIM、GeneCards和DrugBank数据库检索HUA疾病靶点。使用Cytoscape 3.7.2软件进行作用靶点-活性成分-疾病网络绘制,利用Metascape平台进行富集分析。使用AutoDockTools 1.5.6软件进行分子对接,对活性成分及重要靶点的结合度进行验证。结果表明,共筛选出核桃活性成分5种,与HUA有交集靶点16个;富集程度较高的信号通路包括癌症信号通路、化学致癌-受体激活信号通路、糖尿病并发症中的晚期糖基化产物-晚期糖基化终末产物受体信号通路和卡波西肉瘤相关疱疹病毒信号通路;通过分子对接验证试验可知,核桃中主要活性成分与重要靶点结合紧密。

湖北省郧西核桃炭疽病病原菌的分离鉴定

炭疽病是危害湖北省郧西县核桃(Juglans regia)的重要病害,从典型炭疽病症状的核桃叶片上分离到1株真菌菌株,经过单孢分离纯化后,基于菌落形态、分子鉴定和柯赫氏法则验证等方法,对该菌株进行了鉴定。经菌落特性和孢子形态初步确定NYF2-2属于刺盘孢属(Colletotrichum spp.)真菌;致病性测定结果表明,菌株NYF2-2接种后引起的病害特征和核桃炭疽病病害特征一致;基于多基因序列采用最大似然法构建的炭疽病菌系统发育树显示,菌株NYF2-2与胶孢炭疽菌(Colletotrichum gloeosporioides)聚为一支。综合形态学、分子鉴定和致病性测定结果,将分离到的病原菌NYF2-2鉴定为胶孢炭疽菌。

核桃炭疽病的研究进展

核桃炭疽病是核桃(Juglans regia L.)的主要病害,严重威胁核桃产业的迅猛发展。近来年,随着核桃种植面积的进一步增加,该病害频频暴发,给核桃产业造成巨大的损失,极大地制约了该产业的发展壮大。结合国内外的相关报道综合论述该病害的研究进展,从其发病症状、发病规律、病原菌特性和防治方法等方面进行阐述。

Thinning effects on walnut stem and crown diameter growth and fruiting in the walnut-fruit forests of Kyrgyzstan

The walnut-fruit forests （Juglans regia L.） in southern Kyrgyzstan are considered to be biodiversity hotspots and of considerable economic and ecological importance to local populations. The fruiting ability and stability of these forests are, however, decreasing because of infrequent silvicultural interventions and non-existent natural regeneration. Continuous inventories and walnut harvest measurements were carded out on 18 trial and control plots over the course of i3 year. Results showed that i） thinning had a positive influence on diameter at breast height （dbh） increase, ii） dbh growth and crown area increases are strongly and positively correlated, iii） large crowns enhanced the production of fruits, and iv） temperature conditions had a major influence on the production of fruits. The above-mentioned points are particularly relevant for young plantations but are also valid for relatively old plantations （〉 50 years）. We conclude that regular thinning substantially improves diameter growth, fruit production and ability of trees to withstand wind and snow damage in both young stands and in older walnut-fruit forests.

基于网络药理学的核桃防治老年痴呆功能成分及其作用靶点研究

基于网络药理学方法探究核桃(Juglans regia L.)防治老年痴呆(Alzheimer's disease,AD)的作用机制,通过TCMSP数据库和文献挖掘获得核桃的活性成分及相应潜在靶点;使用OMIM等数据库进行AD相关基因预测和筛选;采用Cytoscape 3.7.2软件构建“药物-活性成分-疾病-靶点”网络以形成核桃防治AD的成分及靶点相互作用关系,并进行GO功能和KEGG通路富集分析。结果表明,筛选获得29种核桃活性成分,其中17种成分具有AD相关靶点159个,PTGS1/2、RXRA、RELA、MAOB和NOS3可能是AD的关键靶点,主要信号通路为AGE-RAGE信号通路、动脉粥样硬化、PI3K-Akt信号通路、IL-17信号通路和HIF-1信号通路。核桃通过多成分、多靶点、多途径防治AD,其中作用靶点最多的成分为槲皮素、油酸、鞣花酸;受最多化合物作用的靶点为前列腺素过氧化物合成酶、视黄酸受体、转录因子p65、单胺氧化酶和一氧化氮合酶。

核桃主要害虫防治研究进展

随着核桃(Juglans regia L.)种植面积的逐步扩大,栽培管理方式粗放,导致核桃的虫害发生日渐增多、严重,致使核桃产量、品质和效益均受到很大损害。调查研究核桃害虫种类、危害特征和发生规律,从而进行有针对性的综合防治,已是目前核桃产业亟需解决的问题。文章概述了核桃主要害虫危害特征和发生规律及其防治措施,并对核桃主要害虫防治提出展望,以期促进核桃产业健康持续发展。

High demand for firewood leads to overuse of walnut-fruit forests in Kyrgyzstan

After Kyrgyzstan gained independence in 1991, the importance of the primary sector for food- and energy-supply increased significantly. This has led to a discussion about the sustainability of current firewood use. We investigated firewood collection and use practices in three selected villages and analysed differences between the annual increment of woody biomass and firewood consumption for heating during winter months. The calculated individual firewood consumption is on average 3.90 kg/capita/heating day and the calculation of differences between increment and consumption shows that in minimum one village the surrounding forests are overused for firewood collection. Pressure on the forest and the overuse of preferred tree species for firewood can lead to an overuse of the resource and to a decrease in the genetic diversity of these species in the walnut-fruit forests which are considered as a biodiversity hotspot of international significance due to the diversity of woody.

配方型叶面微肥铃丹对核桃产果的影响

以林龄6年处于试果期核桃林为对象,研究了施用配方型叶面微肥铃丹对核桃(Juglans regia)单株产果量及坚果品质相关性状的影响。结果表明,施用配方型叶面微肥铃丹对核桃果产量及农艺性状有较大影响,其可提高核桃单株产干果质量,减小核桃果外形,降低核桃果壳质量,增加出仁率,但不影响果壳厚度。

核桃古树健康评价体系的建立与应用

核桃(Juglans regia L.)是全球重要的木本油料树种之一,在乡村振兴中发挥着重要作用,核桃古树还具有重要的文化和科学价值。为科学、准确评估核桃古树健康状况,采用层次分析法,建立6个约束层要素、17个标准层要素的评价体系,通过两两赋值,构建定性与定量相结合的评价层次模型,并运用该体系筛选左权县健康核桃古树。研究表明:约束层(S)要素对目标层(T)重要性排序为:根系裸露程度(权重:0.1551)、根部腐朽程度(权重:0.1551)、树龄(权重:0.1135)、生境状况(权重:0.0852)、树干内部腐烂和空洞(权重:0.0852)、树木倾斜度(权重:0.0568)、树皮损伤度(权重:0.0426)、树干病虫害(权重:0.0426)、阳光遮挡(权重:0.0426)和坡度(权重:0.0426),10个指标对目标层重要性的权重值合计达82.1%,是核桃古树健康评价的决定性评价要素。筛选左权县优质健康核桃古树资源78株,集中分布在县域东、东南及南部。核桃古树健康评价体系有利于开展核桃古树分级保护,可为核桃古树产业发展与其他古树资源健康评价提供依据与参考。