Transcriptome and weighted gene co-expression network analysis of jujube(Ziziphus jujuba Mill.)fruit reveal putative genes involved in proanthocyanin biosynthesis and regulation

Proanthocyanidin(PA)is an important bioactive compound with multiple physiological benefits in jujube(Ziziphus jujube Mill.).However,the molecular mechanisms underlying PA biosynthesis in jujube fruit have not been investigated.Here,the profiling of PA,(+)-catechin and(–)-epicatechin and transcriptome sequencing of three jujube cultivars from Xinjiang Uyghur Autonomous Region of China at five developmental stages were analyzed.The levels of total PAs and catechin exhibited a decreased trend over jujube ripening,and epicatechin content of two jujube cultivars increased first and then declined.Transcriptome analysis revealed that the differentially expressed genes(DEGs)were mainly enriched in ribosome,glycolysis/gluconeogenesis,fructose and mannose metabolism.17 DEGs encoding PAL,CHS,CHI,CHS,F3'H,LAR,ANR,C4Hs,4CLs,FLSs,DFRs and UFGTs involved in PA biosynthesis were relatively abundant.The highly transcribed LAR gene may greatly contribute to epicatechin accumulation.A weighted gene co-expression network analysis(WGCNA)was performed,and a network module including 1620 genes highly correlated with content of Pas and catechin was established.We identified 58 genes including 9 structural genes and 49 regulatory genes related to PA biosynthesis and regulation in the WGCNA module.Sixteen genes encoding 9 families of transcriptional factors(i.e.,MYB,bHLH,ERF,bZIP,NAC,SBP,MIKC,HB,WRKY)were considered as hub genes.The results of qRT-PCR analysis validating 10 genes were well consistent with the transcriptome data.These findings provide valuable knowledge to facilitate its genetic studies and molecular breeding.

Effects of IBA on the rooting of branch cuttings of Chinese jujube (Zizyphus jujuba Mill.) and changes to nutrients and endogenous hormones

‘Zhongqiusucui’ jujube secondary shoots were treated with 3-indolebutyric acid(IBA) at three concentrations, 500, 1000 and 1500 mg/L. Results show that IBA could significantly enhance rooting and root characteristics of cuttings and were best with IBA at 1500 mg/L. In the rooting process, the formation of adventitious roots was related to the consumption and accumulation of nutrients(soluble sugars and proteins) and the changes in endogenous hormones in phloem, leaf tips and leaf bases. The rooting of cuttings had a positive correlation with the consumption of soluble sugars during the period of callus formation and with the accumulation of soluble sugars during adventitious root formation and growth. Rooting was positively related to the breakdown of soluble proteins in the phloem when the callus formed, and had a positive correlation with its accumulation during adventitious root formation and growth. Leaf tips and leaf bases showed a reverse trend in changes of soluble protein. However, together with the phloem, leaf tips and leaf bases regulated and controlled the formation and development of adventitious roots. The main activities of soluble proteins exist in the leaf tips as this was the main source of soluble proteins. The relation between rooting and IAA(indole-3-acetic acid) content in phloem was positive and thus a high concentration of IAA could benefit the induction and formation of adventitious roots. However, rooting was negatively related with ABA(abscisic acid) and GA(gibberellic acid) and a high concentration of both could inhibit the induction and formation of adventitious roots. Rooting had a positive correlation with phloem IAA/ABA ratios, and higher ratios could improve rooting. Low concentrations of ZR(zeatin riboside) triggered the induction of adventitious roots, while higher concentrations promoted root growth.Endogenous hormones in leaf tips and bases had an impact on rooting. The activities of endogenous hormones mainly existed in leaf tips because they play a major role in the production and consumption of IAA and its ABA content increased during rooting. The ZR in leaf tips influenced the rooting of cuttings, especially in the callus formation and rooting stage. Leaf tips were the main source of GA.

Research Progress on Functional Components and Pharmacological Effects of Red Jujube ( Ziziphus jujuba Mill.)

Red jujube(Ziziphus jujuba Mill.),as a traditional Chinese medicine and edible plant,has a long history and extensive uses.Red jujubes are not only widely used in the food industry and traditional Chinese medicine preparations,but also have attracted widespread research interest due to their rich functional components and various pharmacological effects.This paper reviewed the main functional components of jujubes,including polysaccharides,triterpenoid saponins,organic acids and alkaloids,and discussed in detail the pharmacological effects of these components such as blood sugar-regulating,antioxidant,anti-inflammatory and anti-tumor effects.Furthermore,the paper also summarized the safety issues such as drug interactions and toxic side effects of jujubes,and prospected the future development direction of jujube research.

Dew measurement and estimation of rain-fed jujube (Zizyphus jujube Mill) in a semi-arid loess hilly region of China

Dew is an important water source for plants in arid and semi-arid regions. However, information on dew is scarce in such regions. In this study, we explored dew formation, amount, and duration of rain-fed jujube（Zizyphus jujube Mill） trees in a semi-arid loess hilly region of China（i.e., Mizhi County）. The data included dew intensity and duration, relative humidity, temperature, and wind speed measured from 26 July to 23 October, 2012 and from 24 June to 17 October, 2013 using a micro-climate system（including dielectric leaf wetness sensors, VP-3 Relative Humidity/Temperature Sensor, High Resolution Rain Gauge, and Davis Cup Anemometer）. The results show that atmospheric conditions of relative humidity of 〉78% and dew point temperature of 1°C–3°C are significantly favorable to dew formation. Compared with the rainfall, dew was characterized by high frequency, strong stability, and long duration. Furthermore, heavy dew accounted for a large proportion of the total amount. The empirical models（i.e., relative humidity model（RH model） and dew point depression model（DPD model）） for daily dew duration estimation performed well at 15-min intervals, with low errors ranging between 1.29 and 1.60 h, respectively. But it should be noted that the models should be calibrated firstly by determining the optimal thresholds of relatively humidity for RH model and dew point depression for DPD model. For rain-fed jujube trees in the semi-arid loess hilly regions of China, the optimal threshold of relative humidity was 78%, and the optimal upper and lower thresholds of dew point depression were 1°C and 5°C, respectively. The study further demonstrates that dew is an important water resource that cannot be ignored for rain-fed jujube trees and may affect water balance at regional scales.

Differences in leaf cuticular wax induced by whole-genome duplication in autotetraploid sour jujube

Drought-resistant plants exhibit strong water retention capability.In this regard,the autotetraploid sour jujube leaves exhibit better water retention than diploid leaves.Morphological comparisons and physiological comparisons of diploid and autotetraploid leaves showed that the autotetraploid leaves had thicker leaf cuticles and more leaf wax accumulation than the diploid leaves,which could reduce cuticle permeability and improve the drought tolerance of leaves.In this study,the cuticular wax crystalloids on the adaxial and abaxial sides of young and mature jujube leaves were observed in the two ploidy types,and unique cuticular wax crystalloids covering a large area of the cuticle on autotetraploid sour jujube leaves may provide an advantage in reducing leaf non-stomata transpiration and improving plant drought tolerance.Based on the transcriptome,115 differentially expressed genes between diploids and autotetraploids were further analyzed and found to be involved in the accumulation of cuticular wax components,including terpenoids,fatty acids,and lipids,as well as ABC transporter and wax biosynthetic process.Finally,14 genes differentially expressed between glossy autotetraploid leaves and nonglossy diploid leaves,such as LOC107414787,LOC107411574 and LOC107413721,were screened as candidate genes by qRT-PCR analysis.This findings provided insights into how polyploidization improved drought tolerance.

Geographical origin identification of winter jujube(Ziziphus jujuba Dongzao')by using multi-element fingerprinting with chemometrics

Winter jujube(Ziziphus jujuba'Dongzao')is greatly appreciated by consumers for its excellent quality,but brand infringement frequently occurs in the market.Here,we first determined a total of 38 elements in 167 winter jujube samples from the main winter jujube producing areas of China by inductively coupled plasma mass spectrometer(ICP-MS).As a result,16 elements(Mg,K,Mn,Cu,Zn,Mo,Ba,Be,As,Se,Cd,Sb,Ce,Er,Tl,and Pb)exhibited significant differences in samples from different producing areas.Supervised linear discriminant analysis(LDA)and orthogonal projection to latent structures discriminant analysis(OPLS-DA)showed better performance in identifying the origin of samples than unsupervised principal component analysis(PCA).LDA and OPLS-DA had a mean identification accuracy of 87.84 and 94.64%in the testing set,respectively.By using the multilayer perceptron(MLP)and C5.0,the prediction accuracy of the models could reach 96.36 and 91.06%,respectively.Based on the above four chemometric methods,Cd,Tl,Mo and Se were selected as the main variables and principal markers for the origin identification of winter jujube.Overall,this study demonstrates that it is practical and precise to identify the origin of winter jujube through multi-element fingerprint analysis with chemometrics,and may also provide reference for establishing the origin traceability system of other fruits.

GST family genes in jujube actively respond to phytoplasma infection

Jujube witches’broom(JWB)caused by phytoplasma has a severely negative effect on multiple metabolisms in jujube.The GST gene family in plants participates in the regulation of a variety of biotic and abiotic stresses.This study aims to identify and reveal the changes in the jujube GST gene family in response to phytoplasma infection.Here,70 ZjGSTs were identified in the jujube genome and divided into 8 classes.Among them,the Tau-class,including 44 genes,was the largest.Phylogenetic analysis indicated that Tau-class genes were highly conserved among species,such as Arabidopsis,cotton,chickpea,and rice.Through chromosome location analysis,37.1%of genes were clustered,and 8 of 9 gene clusters were composed of Tau class members.Through RT-PCR,qRT-PCR and enzyme activity detection,the results showed that the expression of half(20/40)of the tested ZjGSTs was inhibited by phytoplasma infection in field and tissue culture conditions,and GST activity was also significantly reduced.In the resistant and susceptible varieties under phytoplasma infection,ZjGSTU49-ZjGSTU54 in the cluster IV showed opposite expression patterns,which may be due to functional divergence during evolution.Some upregulated genes(ZjGSTU45,ZjGSTU49,ZjGSTU59,and ZjGSTU70)might be involved in the process of jujube against JWB.The yeast two-hybrid results showed that all 6 Tauclass proteins tested could form homodimers or heterodimers.Overall,the comprehensive analysis of the jujube GST gene family revealed that ZjGSTs responded actively to phytoplasma infection.Furthermore,some screened genes(ZjGSTU24,ZjGSTU49-52,ZjGSTU70,and ZjDHAR10)will contribute to further functional studies of jujube-phytoplasma interactions.

Utilization of Changyun Jujube, a Cultivar with Resistance to Witches Broom Disease

In 2021,the Shanting District Fruit Industry Service Center conducted an application test of a treatment for jujube witches broom disease using Changyun jujube.The results demonstrated that when diseased Changhong jujube plants were grafted with Changyun jujube in the spring using bark or cleft grafting,the majority of the new shoots of Changyun jujube exhibited no symptoms of witches broom disease,while a few exhibited symptoms of the disease.With the growth of new shoots,the symptoms of witches broom disease gradually abated,returning to normal growth and development.Similarly,the symptoms of witches broom disease on the rootstock below the grafting mouth also gradually abated,returning to normal.The Changyun jujube rootstock was utilized as the intermediate rootstock to grafting the jujube cultivars Qiyuexian and Fucuimi.The two cultivars were subsequently affixed with branch bark from the witches broom disease.The two cultivars did not exhibit any symptoms of witches broom disease,thus providing an opportunity to investigate potential treatments for this disease in jujube.Finally,the cultivation techniques of the Changyun jujube were presented.

Current Status of Clinical Application and Basic Research on Draba nemerosa Hebecarpa Jujube Lung-Diarrhoea Soup

The clinical application and basic research of Draba nemerosa Hebecarpa jujube diarrhoea lung soup focus on respiratory diseases and circulatory diseases, and its clinical application is more compared with the basic research, and Draba nemerosa Hebecarpa jujube diarrhoea lung soup is mostly used in the form of “Draba nemerosa Hebecarpa Hebecarpa jujube diarrhoea lung soup with additional subtractions or other formulas combining Draba nemerosa Hebecarpa Hebecarpa Hebecarpa jujube diarrhoea lung soup” in the clinical application. This article will focus on the main mechanisms of Draba nemerosa Hebecarpa jujube diarrhoea lung soup and its main components in the treatment of respiratory and circulatory diseases, and will give a review of the basic research on Draba nemerosa Hebecarpa Hebecarpa jujube diarrhoea lung soup as follows.

枣树(Zizyphus jujuba Mill.)叶片内氮素贮藏和循环利用的研究

金丝小枣秋季叶施^(15)N-尿素后,研究了氮素在其体内的贮藏部位、形态及循环利用情况。结果表明,幼树秋季叶弛的^(15)N可以输送到树体的各器官,地上部和根系在贮藏氮素上有同等重要的作用,根系可以利用来自叶片的氮供其生长。枣树春季生长先利用地上部贮藏的氮,而叶片回流的氮则优先用于梢、叶、花的形成。成年树分配到花的氮的比例较幼树大。秋季在成年树枣股叶片施用^(15)N-尿素,次年该枣股中的`(15)N量高于其上、下邻近枣股,表现局部贮藏局部优先利用的特点。氮素有较长时期重复利用的效应,重复利用的氮主要来自叶片。

Intellectual Property Protection and New Development Pattern Construction of Xinjiang Jujube

"Three new developments"is the guiding ideology of Chinese-style high-quality development in the new era.Jujube(Zizyphus jujube Mill.)is a plant of Zizyphus of Rhamnaceae,which originated in China and has been listed as one of the"five fruits"since ancient times.Xinjiang is the most important jujube producing area in China,and its yield has accounted for 50%of the national jujube yield.In the five prefectures and cities of southern Xinjiang,as well as the regimental farms of southern and eastern Xinjiang of Xinjiang Production and Construction Corps,the jujube industry is an advantageous characteristic industry in agriculture.This paper studied Xinjiang jujube industry and its agricultural intellectual property resources,analyzed six major issues to be further implemented,such as the"three new developments"thinking and the strategy of building an intellectual property power,and puts forward eight strategies such as coordinating the two markets and two resources to accelerate the construction of a new development pattern and dual circulation of jujube.

酸枣 (Zizyphus jujuba Mill)组织培养结合^(60)Co- γ射线辐照诱发突变株(英文)

建立了酸枣离体组织培养结合 6 0 Co γ射线辐照获得突变株的技术。 (1)酸枣叶片外植体在含有ZEA 1mg L ,2 ,4 D 0 .5mg L和NAA0 .5mg L的MS培养基上诱导愈伤组织 :经 6 0 Co γ射线辐照后在含有ZEA 1mg L和NAA0 .5 mg L的MS培养基上诱导幼苗 ;(2 )试管苗用 2 0～ 30Gy6 0 Co γ射线辐照后 ,在BAP 2mg L和IBA 0 .4mg L的MS培养基上进行不定苗繁殖。 (3)不定苗在含有IBA 1mg L和IAA0 .4mg L的MS培养基上生根。此外 ,用 2 0 0～ 4 5 0Gy6 0 Co γ射线辐照种仁 ,也能获得突变株。

Genome-wide identification and analysis of the DREB genes and their expression profiles under abiotic stresses in Chinese jujube(Ziziphus jujuba Mill.)

CBF/DREB proteins play a critical role in abiotic stress-mediated gene expression and represent attractive regulons for plant breeding programs.However,no study has been conducted for CBF/DREB protein-related genes in jujube(Ziziphus jujuba Mill.).In this study,twenty-five ZjDREB genes were identified and annotated from the jujube(Z.jujuba‘Dongzao’)genome.Detailed analysis,including gene classification,annotation,phylogenetic evaluation,conserved motif determination and expression profiling were performed on all genes.Phylogenetic analysis showed that ZjDREB proteins were divided into five subgroups(A1–A5),but lacking a subgroup A6 corresponding to AtDREBs.The ZjDREB genes were distributed in nine of twelve chromosomes in the genome.Additionally,the expression patterns of the DREB genes under different abiotic stresses were investigated using q RT-PCR.Nineteen ZjDREB genes were down-regulated under low temperature,in contrast six ZjDREB genes(01,03,05,11,23 and 24)were up-regulated.Under drought,salinity and high temperature conditions,expression of ZjDREB03,09,10,14,15,17 and 20 genes were induced and showed similar expression patterns,suggesting that various stress conditions share common elements in the signaling pathway.The results suggest that the family of DREB genes play an important role in abiotic stresses in jujube,and provide a foundation for further functional studies of this important class of transcriptional regulators.

Storage and Remobilization of Nitrogen by Chinese Jujube(Z. jujuba Mill. var. inermis Rehd) Seedling as Affected by Timing of ^(15)N Supply

Winter jujube orchard nitrogen （N） management aims at increasing N reserves to meet the tree＇s growth requirements. Fertilization strategies should maximize the efficiency of fertilizers, including the choice of the optimal timing of N supply. ^15N-urea was applied to winter jujubes on Jinsixiaozao jujubes rootstock to evaluate the effect of application timing on Nstorage and remobilization in mature trees in pot culture. The treatments consisted of ground application before budding （BB）, during fruit core-hardening stage （FCH）, and fruit rapid-swelling stage （FRS）. Nitrogen-use efficiency of treatments were significantly different, which were 2.42% （BB）, 9.77% （FCH）, and 9.01% （FRS） in the dormant and 5.20% （BB）, 16.16% （FCH）, and 10.30% （FRS） in the following full-bloom. N supply in the pre-harvest helped to increase N-reserves of trees and then translocate to the new growth organs the following year. The largest amount of ^15N was detected in the roots and trunks. In all the treatments, the partition rates were highest in coarse roots, which were 30.43% （BB）, 38.61% （FCH）, and 40.62% （FRS）, respectively. ^15N stored in roots and trunks was used by jujube trees to sustain new growth in the following full-bloom. ^15N applied before budding resulted in lower Ndff% in perennial organs （trunks and coarse roots） sampled in the following full-bloom, but fine roots had highest Ndff% （1.28%）. Other organs recovered similar amount of Ndff%. In contrast, FCH and FRS treatments led to higher Ndff% （4.01-5.15%） in the new growth organs （new growth branches, deciduous spurs, leaves and flowers）, but lower Ndff% in perennial branches （1.49-2.89%）. With the delay of ^15N-urea application time, ^15N increased the partitioning to roots. FCH treatment increased N-storage in perennial organ during winter, which should be remobilized to sustain new growth the following spring.

Spatial variability of leaf wetness under different soil water conditions in rainfed jujube (Ziziphus jujuba Mill.) in the loess hilly region, China

Leaf wetness provides a wide range of benefits not only to leaves,but also to ecosystems and communities.It regulates canopy eco-hydrological processes and drives spatial differences in hydrological flux.In spite of these functions,little remains known about the spatial distribution of leaf wetness under different soil water conditions.Leaf wetness measurements at the top(180 cm),middle(135 cm),and bottom(85 cm)of the canopy positions of rainfed jujube(Ziziphus jujuba Mill.)in the Chinese loess hilly region were obtained along with meteorological and soil water conditions during the growing seasons in 2019 and 2020.Under soil water non-deficit condition,the frequency of occurrence of leaf wetness was 5.45%higher at the top than at the middle and bottom of the canopy positions.The frequency of occurrence of leaf wetness at the top,middle and bottom of the canopy positions was over 80%at 17:00‒18:00(LST).However,the occurrence of leaf wetness at the top was earlier than those at the middle and bottom of the canopy positions.Correspondingly,leaf drying at the top was also latter than those at the middle and bottom of the canopy positions.Leaf wetness duration at the middle was similar to that at the bottom of the canopy position,but about 1.46-3.01 h less than that at the top.Under soil water deficit condition,the frequency of occurrence of leaf wetness(4.92%-45.45%)followed the order of top>middle>bottom of the canopy position.As the onset of leaf wetness was delayed,the onset of wet leaf drying was advanced and the leaf wetness duration was shortened.Leaf wetness duration at the top was linearly related(R^(2)>0.70)to those at the middle and bottom of the canopy positions under different soil water conditions.In conclusion,the hydrological processes at canopy surfaces of rainfed jujube depended on the position of leaves,thus adjusting canopy structure to redistribute hydrological process is a way to meet the water need of jujube.

Effect of pruning intensity on soil moisture and water use efficiency in jujube(Ziziphus jujube Mill.) plantations in the hilly Loess Plateau Region, China

Jujube(Ziziphus jujube Mill.)is a traditional economic forest crop and is widely cultivated in hilly areas of the Loess Plateau,China.However,soil desiccation was discovered in jujube plantations.Pruning is recognized as a water-saving method that can reduces soil water consumption.In this study,we monitored the jujube plots with control(CK),light(C1),medium(C2)and high(C3)pruning intensities during the jujube growing period of 2012-2015 to explore the effect of pruning intensity on soil moisture and water use efficiency(WUE)of jujube plantations in the hilly Loess Plateau Region.The results showed that pruning is an effective method for soil water conservation in jujube plantations.Soil moisture increased with increasing pruning intensity during the jujube growing period of 2012-2015.C1,C2 and C3 pruning intensities increased soil water storage by 6.1-18.3,14.4-40.0 and 24.3-63.3 mm,respectively,compared to CK pruning intensity.Pruning promoted soil moisture infiltration to deeper soil layer.Soil moisture infiltrated to soil depths of 240,280 and>300 cm under C3 pruning intensity,220,260 and 260 cm under C2 pruning intensity,200,240 and 220 cm under C1 pruning intensity,and 180,200 and 160 cm under CK pruning intensity in 2013,2014 and 2015,respectively.Soil water deficit was alleviated by higher pruning intensity.In 2013-2015,soil water change was positive under C2(6.4 mm)and C3(26.8 mm)pruning intensities but negative under C1(-20.5 mm)and CK(-40.6 mm)pruning intensities.Moreover,pruning significantly improved fresh fruit yield and WUE of jujube plants.Fresh fruit yields were highest under C1 pruning intensity with the values of 6897.1-13,059.3 kg/hm^2,which were 2758.4-4712.8,385.7-1432.1 and 802.8-2331.5 kg/hm2 higher than those under CK,C2,and C3 pruning intensities during the jujube growing period of 2012-2015,respectively.However,C3 pruning intensity had the highest WUE values of 2.92-3.13 kg/m3,which were 1.6-2.0,1.1-1.2 and 1.0-1.1 times greater than those under CK,C1 and C2 pruning intensities,respectively.Therefore,C3 pruning intensity is recommended to jujube plantations for its economic and ecological benefits.These results provide an alternative strategy to mitigate soil desiccation in jujube plantations in the hilly Loess Plateau Region,which is critical for sustainable cultivation of economic forest trees in this region.

Effects of Edible Coatings on Quality and Antioxidant Activity of Zizyphus Jujuba Miller cv. Dongzao During Storage

The development of edible coatings has been lauded with respect to their safety and effectiveness.In this study,we researched the effects of edible coatings(2%CaCl_2,1%chitosan and 1%pullulan) on the nutrient content and antioxidant abilities of jujube(Zizyphus jujuba Miller cv.Dongzao).Using the new analysis technique for order of preference by similarity to ideal solution(TOPSIS),we evaluated the effects of these coatings.Compared with the control fruit group,test results showed that coating treatment significantly delayed fruit senescence.Specifically,CaCl_2 treatment not only maintained fruit storage quality and antioxidant activity but also restrained the production and accumulation of malondialdehyde in jujube.Chitosan treatment delayed decreases in secondary metabolites and superoxide dismutase and catalase activity.Pullulan coatings performed better in terms of proanthocyanidin and cyclic adenosine monophosphate(cAMP).We also used TOPSIS to evaluate the preservation effect of different film coatings and found 2%CaCl_2 to be the best treatment for jujube,followed by 1%chitosan and 1%pullulan.Based on the appropriate materials and concentration of the film coatings,edible coatings have the potential to retain the quality and antioxidant capacity of the Chinese jujube cv.Dongzao.

Jujube(Ziziphus jujuba Mill.(Rhamnaceae)):a review on its pharmacological properties and phytochemistry

Jujube(Ziziphus jujuba Mill.)belongs to the Rhamnaceae family.It is distributed in the tropical and subtropical regions of Europe and Asia,including India,China,Iran,Russia,and the Middle East.Jujube is a highly tolerant tree that is resistant to soil salinity and alkalinity.Jujube possesses many phytochemical components and pharmacological properties that make it a good choice for the human diet.Jujube fruit is nutritious and rich in proteins,minerals,vitamins,organic acids,and carbohydrates.It also contains phytochemical components such as polyphenols,flavonoids,terpenoids,anthocyanins,alkaloids,and carotenoids.Jujube has both nutraceutical and cosmeceutical properties.All parts of this plant possess medicinal properties.Jujube has a long history of use in traditional medicine,especially in traditional Persian medicine.It has many pharmacological properties according to traditional Persian medicine,which include anti-pruritic and tranquilizing effects for renal and bladder pain.In Chinese medicine,jujube is used to increase appetite and treat diarrhea and fatigue.This indicates that jujube has several chemical constituents and beneficially affects multiple organs and tissues.These properties include antioxidant,anti-cancer,antimicrobial,neuroprotective,cardioprotective,and hepatoprotective activities.It also has health-promoting effects,including anti-aging properties.

Effects of methionine treatment on storage quality and antioxidant activity of postharvest jujube fruit

Jujube fruits usually suffer from physiological disorders or infectious diseases during storage,leading to quality deterioration,softening,or rotting.Therefore,this study aims to investigate the effect of methionine soaking treatment on the postharvest jujube fruit decay rate and storage quality.Methionine treatment significantly reduced the decay rate of postharvest jujube fruit and effectively maintained fruit color and titratable acid.Methionine treatment effectively delayed the decrease of firmness,soluble solids,ascorbic acid,and lignin contents in jujube fruit.Methionine treatment reduced the content of alanine and phenylalanine,and increased the content of glycine in jujube fruit,but displayed no significant effect on total amino acid content.In addition,jujube fruits in the methionine treatment group had a higher total phenolic and flavonoid content and antioxidant capacity,both in free and bound forms.Compared with the control,methionine treatment also significantly increased the content of individual phenolic acid fractions(gallic acid,vanillic acid,and syringic acid)and flavonoid fractions(catechin,epicatechin,rutin)in free form as well as individual phenolic acid fractions in bound form(gallic acid and ferulic acid)in jujube fruits.Overall,this study suggested that the methionine treatment could be used as a prospective preservative to reduce the postharvest decay of jujube fruit and alleviate its nutritional quality deterioration during cold storage at 4°C.

A cyclic effect of cAMP and calcium signaling contributes to jujube growth and development

3´,5´-Cyclic adenosine monophosphate(cAMP)is an important metabolite that is specifically enriched in jujube.However,the effect of cAMP on jujube cellular responses has not been comprehensively studied.Here,we established jujube cell suspension cultures and investigated the calcium influx in response to cAMP treatment through protoplast isolation and fluorescence intensity.Firstly,cAMP treatment could promote jujube growth and increase the content of endogenous cAMP.Using transcriptome analysis with transgenic Arabidopsis plants overexpressing adenylate cyclase(ZjAC)as a positive control,we identified 60 calcium-related differential expressed genes(DEGs)that contributed to the calcium signaling and inter-or intra-cellular responses.Pharmacological treatments such as cAMP and the calcium ionophore A23187 could induce ZjAC expression,the accumulation of cAMP and calcium influx in jujube cells,while ethylene glycol tetraacetic acid(EGTA)or bithionol treatment inhibited these changes.Moreover,the calcium channels and transporters in calcium influx,such as the ZjCNGC2 channel and the mitogen activated protein(MAP)kinase pathway,could be activated by cAMP treatment.In summary,our findings demonstrated that cAMP biosynthesis is dependent on calcium influx and the amplifying effect between calcium and cAMP may be involved in intracellular signal induction,which might contribute to the growth and development of jujube.