Jujube Fruit Research Articles

Identification and Functional Analysis of Key Genes Regulating Organic Acid Metabolism in Jujube Fruit

Organic acids are crucial indicators of fruit flavor quality, but the metabolic characteristics and regulatory genes of organic acids during jujube fruit development remain largely unexplored. In this study, the cultivar ‘Heigeda’ with a high organic acid content was used as the experimental material. The organic acid content was quantified, and key candidate genes were identified through transcriptome analysis. The results indicated that malic acid and citric acid were the main organic acid content in jujube fruit and increased gradually with fruit development. Transcriptome analysis identified nine genes associated with malic acid and seven with citric acid, with four genes co-regulating malic acid and citric acid. Functional assays by transient overexpression and silencing of these four genes in the jujube fruits revealed that overexpression significantly upregulated the malic and citric acid content. However, only the silencing of aconitase1 (ZjACO1) and aconitase3 (ZjACO3) significantly downregulated the content of malic and citric acids. Therefore, aconitase1 (ZjACO1) and aconitase3 (ZjACO3) are considered the key genes that regulate the metabolism of citric acid and malic acid in jujube fruits. Our study can enrich the regulation mechanism of the organic acid metabolism of jujube fruit and provide theoretical support for the efficient cultivation of jujube fruit.

ИЗУЧЕНИЕ И СТАНДАРТИЗАЦИЯ ПОЛИЭКСТРАКТА ПЛОДОВ ЗИЗИФУСА ОБЫКНОВЕННОГО

The main quality indicator for polyextracts is the content of biologically active substances (BAS). Depending on the presence of various groups of biologically active substances, the consistency and stability of the extracts, the regulatory documentation for the extracts contains requirements regarding their composition and quality. Liquid extracts are standardized according to the content of ethyl alcohol. Thick and dry extracts are assessed by their moisture content. Heavy metals are determined in all extracts. Standardization of plant extracts is carried out in accordance with the current regulatory documentation, namely the State Pharmacopoeia of the Russian Federation [1-4]. In this study, using the following methods: GC - MS, TLC and UV spectrophotometry, we studied extracts of the fruits of the common jujube Ziziphus Jujuba Mill., obtained by cascade extraction of raw materials with a solvent system with increasing polarity for maximum depletion of raw materials according to the main groups of biologically active substances. As a result of the work, the quality indicators of the polyextract of jujube fruits were determined and the drug was standardized in terms of the content of total flavonoids and total polysaccharides. The work was carried out in accordance with the research topic of the Federal State Budgetary Scientific Institution VILAR FGUU-2022-0011.

Regulatory network of flavonoids, phenolic acids and terpenoids biosynthesis in Zizyphus jujuba Mill. cv. Goutou jujube fruits

Flavonoids, phenolic acids and terpenoids are important active ingredients that are biomarkers for evaluating the quality of Zizyphus jujuba Mill. Cv. Goutou jujube fruit. Nevertheless, regulatory network of these active ingredients biosynthesis in jujube fruit is still unclear. Here, integrated metabolomics and transcriptomics analyses were conducted at four different stages during the ripening of jujube fruits. Cytochrome P450 enzymes (CYP450s) and uridine 5′-diphospho-glucuronosyltransferases (UGTs) are pivotal enzymes for flavonoids, phenolic acids and terpenoids biosynthesis in plants. Benzoylmalic acid, a phenolic acid, 4′, 5, 7-trihydroxyflavanon and quercetin-3-O-(6″-p-coumaroyl), two flavonoid metabolites, and jujuboside B1, a triterpenoid metabolite were targeted as they were correlated with both CYP450s and UGTs. Furthermore, networks of TFs, CYP450s and UGTs involved in the target metabolites biosynthesis were elucidated. NAC_1 and bZIP2 up-regulated CYP71A7 expression, while G2-like2 and bHLH_1 positively regulated the CSE expression contributing to promoted benzoylmalic acid biosynthesis. G2-like2, bHLH_1 and bHLH_2 indicated a positive relationship with CYP93D1, CYP86C2/3 or UGT71A16 which were positively correlated with 4′, 5, 7-trihydroxyflavanon biosynthesis. MYB1/2/3, C2H2_2 and WRKY positively regulated expression of CYP82A4 or UGT_1 resulted in increased quercetin-3-O-(6″-p-coumaroyl) galactoside biosynthesis. G2-like2 and bHLH_1 up-regulated 4 C L, CYP93D1 or UGT71A16 was the reason for an increase of jujuboside B1 biosynthesis. The findings provide new insight into molecular breeding of high-quality jujube fruits.

Transcriptome and metabolome reveal the molecular mechanism of quality formation in different planting areas of Ziziphus jujuba Mill. ‘Jingudazao’ fruit

Both environmental and genetic factors have important influences on the quality formation of jujube fruit. To elucidate the molecular mechanism of fruit quality formation with the effects of soil and meteorological factors, transcriptome and metabolome analysis was conducted on Ziziphus jujuba Mill. ‘Jingudazao’ (JG) fruits were harvested from the three areas, Hebei (HB), Shanxi (SX), and Xinjiang (XJ) at the half-red stage. Firstly, meteorological factors and soil conditions have significant effects on jujube fruit quality characteristics. In compared groups, 331, 295, and 297 differentially accumulated metabolites (DAMs) were identified, while the principal DAMs pertaining to carbohydrates, organic acids, amino acids, derivatives, etc. showed that JG_HB had fewer DAMs than JG_XJ and JG_SX. Among them, 20 differentially expressed genes (DEGs), 13 DAMs, and their derivatives participated in carbohydrates and acid metabolism. In addition, two DEGs and seven DAMs were involved in flavonoid biosynthesis. The results provide a valuable and theoretical foundation for the ecological planting and cultivation of jujube.

Effect of layering sequence and jujube fruit seed addition on the mechanical, water absorption and bio-degradation properties of Indian almond/peepal hybrid composites

Hybrid composite comprised fibers like peepal and Indian almond was fabricated, with the addition of natural filler such as jujube fruit seed particles aimed at enhancing composite performance. The impact of jujube fruit seed particles and layering sequence on the mechanical properties, water absorption and bio-degradation of the composites was investigated. Initially, two composite types, IA/P/IA (Indian almond/Peepal/Indian almond) and P/IA/P (Peepal/Indian almond/Peepal), were produced using hand layup practice, altering layering sequence of fibers. Based on tensile test results, the P/IA/P composite emerged as the optimal choice due to the denser packing of high-strength peepal fiber. Subsequently, jujube fruit seed particles were incorporated into the P/IA/P composite at varying weight percentages ranging from 2.5 to 10 with a step size of 2.5. The effect of jujube fruit seed particles on the performance of the P/IA/P composite was examined. The P/IA/P/7.5 wt% jujube composite demonstrated superior tensile, flexural, impact, and hardness properties, recording values of 82 MPa, 98 MPa, 5.2 kJ m−2, and 86 shore-d, respectively. These values were 15.4%, 22.5%, 20.9%, and 4.8% higher than those of the P/IA/P composite. The P/IA/P/10 wt% jujube composite demonstrated minimal water absorption, with only 8% recorded over a 12-day period, as well as limited mass loss, totaling 27% over 60 days. Consequently, this research suggests that the P/IA/P/7.5 wt% composite holds promise for industrial applications.

Study on the Metabolic Basis of the Color Formation of Two Color-Presenting Types of Jujube Fruits.

Jujube is a plant of the genus Ziziphus in the family Rhamnaceae; its fruit has high nutritional value, and it is rich in polyphenols, flavonoids, and other secondary metabolites. The color of its peel is an important indicator for evaluating the appearance of the fruit. However, the mechanism of the difference in color presentation between the seedling offspring of the 'Red Fruit' (TLHH) and the 'Green Fruit' (TLHL) of the fresh jujube cultivar 'Tailihong' is not clear. Therefore, this study used targeted metabolomics techniques to accurately and quantitatively analyze the metabolic pathways of carotenoid and anthocyanin metabolites during the ripening process of two color-presenting types of jujube fruits. Through the analysis of the dynamic changes in the pigment content of the jujube peel, it was found that 30 DAP (days after pollination), 80 DAP, and 110 DAP were the key periods for the development of the color of the peel of 'TLHL' and 'TLHH' jujube and that the substances responsible for the main differences were chlorophyll, carotenoids, and anthocyanins. Furthermore, we used an LC-MS/MS metabolic analysis to compare the differences in the carotenoids and anthocyanin metabolites between the two color-presenting types of jujube peels at the key periods of 30 DAP, 80 DAP, and 110 DAP. We detected 32 carotene metabolites and 75 anthocyanin metabolites, respectively, among which lutein had the highest content of carotenoids; it reached the maximum value (93.05 µg/g) and was higher than that of 'TLHH' (74.14 µg/g) at 30 DAP of 'TLHL'. Both showed a decreasing trend with fruit ripening. The anthocyanin with the highest content was cyanidin-3-O-(tartaryl)rhamnoside-5-O-glucoside, which reached the maximum value (258.32 µg/g) at 30 DAP of 'TLHH' and was 51.6 times that of 'TLHL'; similarly, both showed a decreasing trend with fruit ripening. These results elucidate the main metabolites of carotenoids and anthocyanins in the two types of jujube peel and their accumulation characteristics, suggesting that the key metabolites of the difference in color between 'TLHL' and 'TLHH' jujube fruits were lutein and cyanidin-3-O-(tartaryl)rhamnoside-5-O-glucoside, increasing the understanding of the color mechanism of jujube peel and providing a reference for targeted genetic breeding of jujube peel color.

Research Progress and Biosynthetic Mechanisms of Nutritional Compounds Obtained from Various Organs During the Developmental Stages of a Medicinal Plant (Chinese Jujube).

The fruit of the jujube tree is high in nutrients and has various health benefits. China is a major producer of jujube, and it is now cultivated all around the world. Numerous studies have demonstrated the nutritional value and potential health advantages of bioactive compounds found in the jujube tree. Furthermore, the jujube tree has a remarkable 7000-year agricultural history. The jujube plant has developed a rich gene pool, making it a valuable resource for germplasm. Different studies have focused on the developmental stages of jujube fruits to identify the optimal time for harvest and to assess the changes in their bioactive natural compounds or products during the process of development but the molecular mechanism underlying the production of bioactive natural products in Z. jujuba is still poorly understood. Moreover, the potential differential expressed genes (DEGs) identified as responsible for the synthesis of these compounds should be further functionally verified. It has been noticed that the contents of total flavonoids, total phenolic, and vitamin C increase significantly during the ripening process, while the contents of soluble sugars and organic acids decrease gradually. In this review, we have also scrutinized the challenges that hinder the utilization of jujube fruit resources and suggested potential areas for further research. As such, our review serves as a valuable resource for the future development of jujube-based nutritional compounds and the incorporation of their nutritional elements into the functional foods industry.

Regulation of skin pigments in winter jujube fruit treated with elevated O2

Color deterioration is one of the major symptoms of postharvest senescence in winter jujube fruit. Elevated O2 (60 %) was applied to winter jujube fruit during storage at 0 °C and 90 % relative humidity. The changes in three major skin pigments, chlorophyll, carotenoid, and anthocyanin, were quantified to explain changes in skin color. The results showed that elevated O2 maintained the contents of chlorophyll and carotenoid during the initial stages of storage, which were 25 % higher chlorophyll a, 34 % higher chlorophyll b, and 18 % higher carotenoid compared to the control on day 7. The maintenance of chlorophyll content under elevated O2 was due to the inhibition of chlorophyll catabolism. Additionally, elevated O2 treatment also maintained carotenoid content by activating its biosynthesis rather than inhibiting its degradation. During the later stages of storage, the accumulation of anthocyanin was enhanced by elevated O2, with a 1.3-fold increase in anthocyanin observed in elevated O2-treated fruit compared to the control fruit on day 21. Elevated O2 treatment effectively activated phenylpropanoid biosynthesis and flavonoid biosynthesis pathways, leading to the accumulation of anthocyanin. This study elucidated the mechanism by which elevated O2 regulated color deterioration in winter jujube fruit.

Induction of luteolin on postharvest color change and phenylpropanoid metabolism pathway in winter jujube fruit (Ziziphus jujuba Mill. cv. Dongzao)

The postharvest quality of winter jujubes is prone to deterioration, including inevitable pericarp reddening and rapid nutrient loss from the flesh, significantly impacting its edible quality and commercial value. As a crucial metabolic pathway in plants, phenylpropane metabolism not only regulates plant stress resistance but also closely relates to various coloration effects. In this study, we investigated the effects of luteolin solutions on postharvest color changes and phenylpropanoid metabolism in winter jujube. The results indicated that compared to the control group, winter jujube fruit treated with 200 mg L−1 luteolin exhibited improved quality indexes, increased antioxidant capacity (capability of eliminating ABTS and DPPH radicals), and higher activities of antioxidant enzymes(superoxide dismutase (SOD), and catalase (CAT)). This led to a reduction in the oxidation of phenolic substances in winter jujube. Furthermore, luteolin treatment inhibited phenylpropanoid metabolism by suppressing the activities of 4-Coumarate: coenzyme A ligase (4CL), phenylalanine ammonilyase (PAL), and cinnamate 4 hydroxylase (C4H), as well as the expression of ZjUFGT, ZjDFT, and ZjPAL genes. Consequently, anthocyanin and quercetin synthesis were limited while the degradation rate of chlorophyll and carotenoid synthesis were slowed down after luteolin treatment. This resulted in delayed reddening of winter jujube following luteolin treatment. In conclusion, luteolin exhibits potential application prospects as a preservative for inhibiting reddening and browning in winter jujubes.

Quantitative MRI post-processing algorithm and visualization research based on moisture status detection of winter jujube

Quantitative Magnetic Resonance Imaging (qMRI) offers precise measurements of the relaxation characteristics of microstructures, representing a cutting-edge method in non-destructive fruit analysis. This study aims to visualize information on changes in moisture status and distribution at the subcellular level of winter jujube. The 0.5 T nuclear magnetic imaging equipment was utilized to rapidly, non-invasively, and accurately capture the internal relaxation status of the sample with multiple-echo-imaging. By examining the signal and noise data, a simulated dataset was developed to tackle the optimization challenge of estimating parameters for the discrete relaxation model from the multiple-echo-imaging data, especially under conditions of low signal-to-noise ratio (SNR) and in the context of heteroscedastic noise. An optimal weighting factor and the T2NR truncation model have been identified to establish an effective experimental inversion strategy. Subsequently, multiple-echo-imaging can rapidly and stably yielded voxel-level maps under conditions of low signal-to-noise ratio. Utilizing this experimental approach, data from winter jujube was collected and analyzed, facilitating an exploration of water activity (T2 mapping) and associated water content (A2 mapping). Through analyzing winter jujube fruits across two maturity stages, this study elucidates the role of precise quantification and voxel-wise visualization in moisture status detection. The methodology presents an innovative approach for assessing internal moisture distribution in fruits.

Utilization of citrus, date, and jujube substrates for anaerobic digestion processes

AbstractThis research explores the potential for generating biogas and clean energy by processing organic waste, a process that can become a sustainable solution to Syria's energy needs. Focusing on agricultural residues generated from citrus fruit orange, date, and jujube cultivation in Syria, this study evaluates the potential for anaerobic digestion of these residues for biogas production. It highlights the influence of substrate composition and the optimization of fermentation processes on biogas and methane production. The study focuses on evaluating the anaerobic digestion process by examining various dosages ranging from 20% to 50% dry matter for citrus orange waste, and different types of substrate with a fixed ratio of 20% substrate dry matter. It specifically discusses the factors influencing the inhibitory effect of anaerobic digestion, giving particular consideration to orange waste, a significant byproduct of the citrus industry. The biogas produced maintained a stable methane content when a citrus‐to‐inoculum ratio of 30:70 was used. Jujube waste, characterized by a composition rich in cellulose and hemicellulose, exhibited a higher potential for biogas and methane generation among the fruit waste investigated, particularly when combined with the inoculum in a 20:80 ratio. The research findings underscore the potential of using Syrian agricultural residues, including orange citrus peel, date, and jujube fruit, for the production of biogas through anaerobic digestion.

Electrospun PCL/PVA/PHMB nanofibers incorporating Ziziphus jujuba fruit extract as promising wound dressings with potent antibacterial and antidiabetic properties

This investigation examined the potential antibacterial and antidiabetic effects of wound dressings created using electrospun nanofibers containing Ziziphus jujuba fruit extract (ZJ). These nanofibers were composed of a combination of Polycaprolactone (PCL), Polyvinyl Alcohol (PVA), and Polyhexamethylene Biguanide (PHMB). The process of creating these nanofibers involved electrospinning. The nanofiber products, which included PCL, PCL/PVA, PCL/PVA/ZJ, PCL/PVA/PHMB, and PCL/PVA/PHMB/ZJ, underwent a morphology, physicochemical, and biological assessment. Incorporating PHMB into the nanofibers enhanced the antibacterial properties, effectively preventing bacterial infections in wounds. Furthermore, including ZJ fruit extract in the nanofibers provided antidiabetic properties, making these dressings suitable for diabetic patients. The PCL/PVA/PHMB/ZJ combination exhibited exceptional healing capabilities and superior antibacterial efficiency in MRSA-infected wounds. The histological assay confirmed complete wound healing by day 14, accompanied by reduced inflammation. Based on these findings, using PCL/PVA/PHMB/ZJ as innovative wound dressings is recommended, as they can expedite wound healing while offering significant antidiabetic and antibacterial features. Ultimately, these electrospun nanofibers possess the potential to serve as advanced wound dressings with enhanced antibacterial and anti-diabetes properties.

Combined analysis of transcriptomics with metabolomics provides insights into the resistance mechanism in winter jujube using L-Methionine

Black rots lead to great economic losses in winter jujube industry. The objective of this research was to delve into the underlying mechanisms of enhanced resistance of winter jujube fruit to black rot by L-Methionine (Met) treatment. The findings revealed that the application of Met significantly curtailed lesion diameter and decay incidence in winter jujube fruit. The peroxidase (POD) activity in the Met-treated jujubes was 3.06-fold that in the control jujubes after 4 d of treatment. By day 8, the activities of phenylalanine ammonia-lyase (PAL), chitinase (CHI) and β-1,3-glucanase (GLU) in the Met-treated jujubes had surged to their zenith, being 1.39, 1.22, and 1.52 times in the control group, respectively. At the end of storage, the flavonoid and total phenol content remained 1.58 and 1.06 times than that of the control group. Based on metabolomics and transcriptomics analysis, Met treatment upregulated 6 key differentially expressed metabolites (DEMs) (succinic acid, trans-ferulic acid, salicylic acid, delphinium pigments, (S)-abscisic acid, and hesperidin-7-neohesperidin), 12 key differentially expressed genes (DEGs) (PAL, CYP73A, COMT, 4CL, CAD, POD, UGT72E, ANS, CHS, IAA, TCH4 and PR1), which were involved in phenylpropanoid biosynthesis pathway, flavonoid biosynthesis pathway and plant hormone signal transduction pathway. Further analysis revealed that the most of the enzymes, DEMs and DEGs in this study were associated with both antioxidant and disease resistance. Consequently, Met treatment enhanced disease resistance of winter jujube fruit by elevating antioxidant capacity and triggering defense response. This study might provide theoretical support for utilizing Met in the management and prevention of post-harvest black rot in winter jujube.

Transcriptomic responses of ‘Huping jujube’ (Zizyphus jujuba mill. cv. Huping) fruit to combined treatment of acidic electrolyzed water and high-voltage electrostatic field

The molecular mechanism underlying the preserving superior quality attributes of postharvest Huping jujube fruit by combining acidic electrolyzed water and high-voltage electrostatic field (AH) treatment remained unclear. The high-throughput sequencing analysis revealed a total of 3590 common differentially expressed genes (DEGs) in the T-W-CK0 vs T-W-CK75 and T-W-CK75 vs T-W-AH75 groups. AH treatment down-regulated most genes associated with respiratory metabolism, as well as lignin and anthocyanin biosynthesis, thereby maintaining lower physiological activities, improving taste and color quality of mature-white jujube. Additionally, AH treatment downregulated the genes involved in reactive oxygen species (ROS) generation and disease resistance, while simultaneously upregulating the genes associated with ROS elimination. This suggested that AH treatment could inhibit pathogen infection to prevent the activation of plants’ active defense and reduce the ROS-induced damage. In sum, the present study provided a comprehension explanation that AH treatment improved the storage quality attributes of jujube fruit at the genetic level.

Eco-safe hot water dip alleviates antioxidant level and sensory quality of Indian jujube fruits

Indian jujube (Ber) is highly perishable climacteric fruit owing to high decay index limiting its marketability and demands interventions to prolong shelf life. Fungicides are normally used to control rot during postharvest storage, however, residues left necessitate eco-safe alternatives like hot water dipping. Mature, pre-climacteric jujubes were dipped in 45, 50 or 55 °C water for 8, 6 or 4 min, respectively and then stored at 5 °C for periodic quality evaluation. Dipping fruits in 55 °C water resulted in 32.69 and 35.27, 64.21 and 58.57, 30.41 and 30.42, 38.50 and 52.20 % lower weight loss, decay index, malondialdehyde (MDA) and electrolyte leakage, whereas 15.40 and 16.77, 19.51 and 20.48 % greater antioxidant activity and ascorbic acid respectively for Umran and Pakwhite compared to 25 °C water dip. The highest glucose, fructose, malic, citric, and tartaric acids were 23.44 ± 1.04 and 29.9 ± 0.95, 30.68 ± 1.72 and 41.17 ± 2.34 mg/100 g, 138.1 ± 6.45 and 112.97 ± 6.16, 57.49 ± 1.71 and 53.78 ± 1.90, 79.58 ± 5.1 and 65.3 ± 4.83 μg/100 g whereas lower sucrose 12.34 ± 0.94 and 16.33 ± 1.05 mg/100 g were respectively recorded in 55 °C water dipped Umran and Pakwhite fruits. High dip water temperature (55 °C) exhibited better quality with the lowest decay index and weight loss, greater membrane integrity, bioactives content and sensory acceptance scores. Hence, hot water dipping was shown to be an effective residue-free option to extend the marketable period of jujubes to capture distant markets.

Exogenous brassinolides and calcium chloride synergically maintain quality attributes of jujube fruit (Ziziphus jujuba Mill.)

Jujube fruit, rich in nutritional value, is commonly utilized in the processing of dried jujube fruit, jujube powder, concentrates, and fermented products, but improper storage may lead to quality cracking, diminishing the fruit's quality and commercial value. BR, known for its role as a plant growth regulator, is often applied to maintain postharvest fruit quality. The study investigated the impact of exogenous brassinolide (BR) and calcium chloride (CC) either alone or in combination on the quality attributes of jujube during storage. The results revealed that exogenous BC (BR combined with CC) effectively mitigated the senescence of jujube fruit. Specifically, the redden index, decay index, weight loss, and MDA content of jujube in the BC group decreased by 15 %, 8 %, 33 %, and 41 %, respectively, in comparison to the control group. Furthermore, all treatments maintained higher firmness, ascorbic acid content, total phenol content, chlorophyll content, and antioxidant capacity. Although exogenous BR was able to preserve the quality attributes of jujube, it exhibited instability. Treatment with CC alone was better than treatment with BR alone, but BC treatment maintained a better quality of jujube. The relative conductivity of jujube fruit in the BC group was consistently measured lower than that of the control group, with the exception of 8 d. Exogenous CC and BC were found to inhibit the decrease in total flavonoid and phenol content. Overall, the present study contributes to establishing a theoretical foundation for application of exogenous brassinolide combined with calcium chloride to maintain the postharvest quality attributes of fruit and vegetables.

Effect of dietary supplementation of jujube fruit (Ziziphus jujuba) powder on performance, some biochemical parameters, and egg quality in quails (Coturnix coturnix japonica)

This study aimed to evaluate the effects of different dietary supplementation levels with jujube fruit powder on the performance, biochemical parameters, and egg quality characteristics of laying quails. A total of 60 quails (45 days old) were randomly assigned to treatments with different levels of jujube fruit powder: a basal diet (control) and diets supplemented with 5 g/kg (T1), 10 g/kg (T2), with five replicates per treatment (20 quails/treatment and four quails/replicate). The differences between 1-15 and 16-30 days for feed intake (p<0.05), 1-60 days for egg production (p<0.05), 16-30 days for egg weight (p<0.05), and 1-15 and 1-60 days for feed conversion ratio were statistically significant. The highest values for egg width (p<0.01) and egg length (p<0.05) were found in the control group (25.87 and 33.55 mm), while lower values were observed in the T1 and T2 groups. There was no statistical difference between the groups in egg shape index, shell weight, shell ratio, and shell thickness (p>0.05). The yolk height (p<0.05) and yolk diameter (p<0.01) were statistically significant. The differences between the groups for all serum biochemical parameters were insignificant (p>0.05). According to the results of this study, jujube fruit, a rich energy source, can be used as an alternative supplement in poultry diets with positive effects on egg production and feed conversion ratio.

Antioxidative enzymes, phytochemicals and proximate components in jujube fruit (Ziziphus mauritiana L.) with respect to genotypes and harvest maturity

Jujube is an underutilized fruit having high maturity variation at harvest. Investigations were made on eight different cultivars of jujube (Umran, Karela, Gurrh, Amrodia, Mehmood Wali, Aakash, Foladi and Khubani) for changes in antioxidative enzymatic activities, phytochemical functions and proximate composition with respect to different harvest maturity stages (M1: mature green, M2: yellow and M3: crispy brown) under postharvest ambient conditions (25 ± 2 °C; 60 %–65 % RH) at three shelf intervals (1, 3 and 5 d). Significant genotypic and maturity related variation was recorded regarding studied attributes. The fruit of cv. ʽKhubaniʼ had better attributes among the cultivars evaluated. The crispy brown jujube fruit had higher peroxidase (POD) and catalase (CAT) activity and more protein, total soluble solids (TSS), ash, crude fat and fiber than early mature stages. Over time, the ascorbic acid (vitamin C), titratable acidity (TA), total phenolic (TPC), total antioxidant capacity (TAC), crude protein, crude fiber, moisture, crude fat and activity of antioxidative enzymes [CAT and superoxide dismutase (SOD)] exhibited a significant decline; while increase was recorded in TSS, pH and POD activity. Overall, this work identified that jujube's antioxidative, biochemical and proximate properties are significantly influenced by cultivar, fruit harvest maturity and duration of postharvest handling under ambient shelf.

Variety classification and identification of jujube based on near-infrared spectroscopy and 1D-CNN

Jujube is an important economic crop in Xinjiang, China, and its related industry provides abundant employment opportunities and contributes positively to local economic development. Due to the high economic value and similar appearance of jujubes from different regions, there is a phenomenon of counterfeit products in the market. Therefore, it is necessary to trace the origin of jujubes to address these issues. In this study, we conducted traceability research on jujubes from four locations: Alaer, Hotan, Ruoqiang, and Zhangye. Near-infrared spectroscopy was used to extract non-destructive data from the jujubes for analysis. The extracted data was transformed into one-dimensional data, and six algorithms, including the Back Propagation Neural Network (BP), Radial Basis Function Neural Network(RBF), Convolutional Neural Networks (CNN), Long Short-Term Memory Network(LSTM), Support Vector Machine (SVM), and Random Forest (RF), were used for classification research on the obtained 4000 sets of one-dimensional data. The results showed that when sufficient data were available, the RBF, LSTM and CNN perform relatively better best with 93.50 %, 94.33 % and 94.25 % accuracy. The RF achieved an accuracy of 92.42 % and demonstrated good detection efficiency. However, the BP and SVM performed relatively poorly, with accuracies of 90.42 % and 80.42 % respectively. Considering the time-consuming nature of data collection for large datasets during the detection process, several sets of one-dimensional data were randomly selected for further experiments, through which 400 sets of data were found to be more prominent with 700 sets of data. The final experimental results demonstrate that, in the traceability detection of a small-scale dataset containing 400 instances, the CNN exhibits the best performance, achieving an accuracy of 86.67 %. The performance of the LSTM is slightly lower than that of the CNN, with an accuracy of 84.12 %. The accuracies of the BP, RBF, SVM, and RF were relatively lower at 82.5 %, 82.5 %, 74.12 %, and 74.18 % respectively. In the experiments with a dataset of 700 instances, the performance of CNN stands out prominently. In comparison to the CNN algorithm on the 400-instance dataset and the second-best LSTM algorithm, the accuracy, precision, recall, and F1-score have exhibited significant improvements by 53.13 %, 98.98 %, 481.43 %, and 140.36 %, respectively. The corresponding values are 0.9043, 0.9083, 0.9052, and 0.906. This study demonstrates the non-destructive traceability of jujube fruits using near-infrared spectroscopy data combined with neural network algorithms. Additionally, it reduces the need for additional preprocessing steps in data handling and achieves promising detection results. This research has positive implications for the traceability of jujube fruits and related crops.

Metabolome and transcriptome reveal high abundance of bioactive substances in albino jujube fruit as potential function food

Little is known about the fruit quality of albino mutants, due to generally exhibited lethal phenotypes caused by restrained photosynthesis and energy metabolism. In this study, a non-lethal bud mutant of jujube that could bear fruit with higher nutrient content after leaf albinism was described. Compared to normal mature fruit, the albino fruit contained lower soluble sugar and titratable acid, as well as higher ascorbic acid, phenols and flavonoids contents. Through metabolome and transcriptome analyses, 109, 117, and 126 differentially accumulated metabolites (DAMs) and 1169, 797, and 3059 differentially expressed genes (DEGs) were identified in the young, white-ripened, and mature stages of albino and normal fruits, respectively. KEGG annotation indicated that DEGs and DAMs were mainly enriched in phenylpropanoid and flavonoid biosynthesis, glutathione metabolism, and α-linolenic acid metabolism. Moreover, ADH, GST17, and POD16 were identified as hub genes that play major roles in high abundance of chalcone, (−)-epigallocatechin, GSH, and total ascorbate. The alteration of bioactive substance content in albino fruits was an adaptive molecular mechanism that responded to adverse mutations, and reflected a higher antioxidant capacity. These findings provide new insights into bioactive compounds accumulation in albino mutants, and provide experimental evidence for albino fruit as a potential nutraceutical or functional food.