Comparison of the Bioactive Components in Two Seeds of Ziziphus Species by Different Analytical Approaches Combined with Chemometrics

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.

Sour Jujube (Ziziphus jujuba var. spinosa): A Bibliometric Review of Its Bioactive Profile, Health Benefits and Trends in Food and Medicine Applications

Research on the comprehensive utilization of sour jujube and its beneficial properties to human health has attracted extensive attention. This study aims to conduct a bibliometric analysis of the bioactive profile of sour jujube and future trends in applications. The research advancements within this field from 2000 to 2023 were addressed using the Web of Science database and VOSviewer. Among the 322 results, the most frequent keywords of bioactivity are flavonoids, antioxidants, saponins, insomnia, polyphenols, terpenoids and anti-inflammatory; the most studied parts of sour jujube are seeds, fruits and leaves; the published articles with high citations mainly focus on identification, biological effects and different parts distribution of bioactive compounds. The bioactivity of various parts of sour jujube was reviewed considering their application potential. The seeds, rich in flavonoids, saponins and alkaloids, exhibit strong effects on central nervous system diseases and have been well-developed in pharmacology, healthcare products and functional foods. The pulp has antioxidant properties and is used to develop added-value foods (e.g., juice, vinegar, wine). The leaves can be used to make tea and flowers are good sources of honey; their extracts are rich sources of flavonoids and saponins, which show promising medicinal effects. The branches, roots and bark have healing properties in traditional folk medicine. Overall, this study provides a reference for future applications of sour jujube in food and medicine fields.

Biological Characteristics and Functional Analysis of the Linoleic Acid Synthase Gene ZjFAD2 in Jujube

Jujube fruit is rich in linoleic acid and other bioactive components and has great potential to be used for the development of functional foods. However, the roles of FAD2 genes in linoleic acid biosynthesis in jujube fruit remain unclear. Here, we identified 15 major components in jujube and found that linoleic acid was the main unsaturated fatty acid; major differences in the content and distribution of linoleic acid in the pulp and seeds were observed, and levels of linoleic acid decreased during fruit maturation. Analysis of the fatty acid metabolome, genome, and gene expression patterns of cultivated and wild-type jujube revealed five ZjFAD2 family members highly related to linoleic acid biosynthesis. The heterologous expression of these five ZjFAD2 family members in tobacco revealed that all five of these genes increased the content of linoleic acid. Additionally, transient expression of these genes in jujube fruit and the virus-induced gene silencing (VIGS) test further confirmed the key roles of ZjFAD2-11 and ZjFAD2-1 in the biosynthesis of linoleic acid. The results of this research provide valuable insights into the molecular mechanism underlying linoleic acid synthesis in jujube and will aid the development of quality-oriented breeding strategies.

Untargeted metabolomics reveals sour jujube kernel benefiting the nutritional value and flavor of Morchella esculenta

Nucleosides, organic acids, and amino acids separated from Morchella esculenta are well known for their nutritional value and flavor. However, how to increase their content in a better way has been a challenge. In this study, the effect of adding jujube kernel on the active components of M. esculenta was investigated by untargeted metabolomics using UPLC-MS/MS. A total of 1,243 metabolites were identified, of which 262 metabolites (21.078%) were organic acids and derivatives, 245 metabolites (19.71%) were lipids and lipid-like molecules, and 26 metabolites (2.092%) were nucleosides, nucleotides, and analogues. Subsequently, differential metabolites between groups were screened by the orthogonal partial least squares-discriminant analysis model, which showed that 256 metabolites were identified as significantly different for the positive ion model and 149 for the negative ion model. Moreover, significant differential metabolites (VIP > 1, P < 0.05) in annotation of kyoto encyclopedia of genes and genomes pathway were investigated, which showed that ABC transporters were the most commonly observed transporters, followed by pyrimidine metabolism and purine metabolism. The results indicated that the main components of jujube kernel might be conducive to the accumulation of nucleoside organic acids and amino acid metabolites in M. esculenta. These results provide important information for the understanding of more suitable way for cultivation of M. esculenta.

Research progress of quality control for the seed of Ziziphus jujuba var. spinosa (Bunge) Hu ex H.F. Chow (Suan-Zao-Ren) and its proprietary Chinese medicines

ETHNOPHARMACOLOGICAL RELEVANCE

Semen Ziziphi Spinosae (SZS), the seed of Ziziphus jujuba var. spinosa (Bunge) Hu ex H.F. Chow (Chinese name Suan-Zao-Ren), is widely distributed in China, Laos, Myanmar, and Iran. It is a classic traditional Chinese medicine with sedative and sleeping effects. In clinical practice, there are more than 155 proprietary Chinese medicines containing SZS. However, many commercial SZS products are difficult to qualify using current methods. Moreover, there is a scarcity of quality standards for SZS in proprietary Chinese medicines.

AIM OF THE STUDY

The purpose of this study was to clearly reveal the quality indicators during the entire production process of SZS and its products.

MATERIALS AND METHODS

This study reviewed more than 230 articles and related books on the quality control of SZS and its proprietary Chinese medicines published over the last 40 years (from January 1979 to October 2022). Moreover, where available, information on the quality of SZS and its proprietary Chinese medicines was also collected from websites for comparison, including online publications (e.g. PubMed, CNKI, Google Scholar, and Web of Science), the information at Yaozhi website and China Medical Information Platform, along with some classic books on Chinese herbal medicine. The literature and information search were conducted using keywords such as "Suan-Zao-Ren", " Ziziphus jujuba" and "quality control", and the latest results from various databases were combined to obtain valid information. The active components, which in vivo exposure, and Q-markers were also summarized.

RESULTS

The jujuboside A, jujuboside B, and spinosin were revealed as the key Q-markers for SZS. Moreover, the advancements and prospects of the quality control for SZS and its extract, proprietary Chinese medicines, health foods, and adulterants were comprehensively summarized. The high-performance liquid chromatography-UV/evaporative light scattering detection and fingerprint analysis were found to be the mainstream methods for the SZS quality control. In particular, the novel quality evaluation method based on the unit content was applied for SZS and its proprietary Chinese medicines. Significant fluctuations were found in the contents of Q-markers. Moreover, the mass transfer rule of Q-markers was comprehensively clarified based on the entire production process, including production origins, ripening time, primary process, processing, compatibility decoction/extract, and storage. Ultimately, the crushing and compatibility of SZS were found to be the key steps affecting the active components.

CONCLUSIONS

In short, this study provides solid evidences to reveal quality indicators for the entire production process of developing rational quality standards for SZS and its products. Moreover, this study also provides a template quality control overview, which could be extended to other traditional Chinese medicines.

Transcription Factors ZjMYB39 and ZjMYB4 Regulate Farnesyl Diphosphate Synthase- and Squalene Synthase-Mediated Triterpenoid Biosynthesis in Jujube

Jujube (Ziziphus jujuba Mill.) is rich in valuable bioactive triterpenoids. However, the regulatory mechanism underlying triterpenoid biosynthesis in jujube remains poorly studied. Here, we characterized the triterpenoid content in wild jujube and cultivated jujube. The triterpenoid content was higher in wild jujube than in cultivated jujube, triterpenoids were most abundant in young leaves, buds, and later stages of development. The transcriptome analysis and correlation analysis showed that differentially expressed genes (DEGs) were enriched in the terpenoid synthesis pathways, and triterpenoids content was strongly correlated with farnesyl diphosphate synthase (ZjFPS), squalene synthase (ZjSQS), and transcription factors ZjMYB39 and ZjMYB4 expression. Gene overexpression and silencing analysis indicated that ZjFPS and ZjSQS were key genes in triterpenoid biosynthesis and transcription factors ZjMYB39 and ZjMYB4 regulated triterpenoid biosynthesis. Subcellular localization experiments showed that ZjFPS and ZjSQS were localized to the nucleus and endoplasmic reticulum and ZjMYB39 and ZjMYB4 were localized to the nucleus. Yeast one-hybrid, glucuronidase activity, and dual-luciferase activity assays suggested that ZjMYB39 and ZjMYB4 regulate triterpenoid biosynthesis by directly binding and activating the promoters of ZjFPS and ZjSQS. These findings provide insights into the underlying regulatory network of triterpenoids metabolism in jujube and lay theoretical and practical foundation for molecular breeding.

Wild Jujube (Ziziphus jujuba var. spinosa): A Review of Its Phytonutrients, Health Benefits, Metabolism, and Applications

Wild jujube, Ziziphus jujuba Mill. var. spinosa (Bunge) Hu ex H. F. Chou, as a food and health supplement worldwide, has rich nutritional value. It contains nutrients such as nucleosides, amino acids, polysaccharides, and fatty oils. The fruits, seeds, and leaves of wild jujube can all be used for food, medicine, or health care purposes. Among these, the fruits play many roles, such as antioxidant, antibacterial, and anti-inflammatory functions, and can be used as a natural nutritional supplement to prevent aging. Simultaneously, the mature seed of wild jujube exhibits beneficial effects on central nervous system diseases and is often used for the treatment of insomnia and as a functional food for improving sleep quality and enhancing learning and memory. This review presents an overview of research progress relevant to the phytonutrients, biological functions, metabolism of bioactive compounds, and applications of wild jujube and aims to provide a scientific reference for the development and utilization of this plant.

Flavonoid Glycosides from Ziziphus jujuba var. inermis (Bunge) Rehder Seeds Inhibit α-Melanocyte-Stimulating Hormone-Mediated Melanogenesis

Ziziphus jujuba extracts possess a broad spectrum of biological activities, such as antioxidant and anticancer activities in melanoma cancers. Nevertheless, the compounds contain high antioxidant capacities and anticancer activities in melanoma cells, shown to be effective in hyperpigmentation disorders, but whether flavonoid glycosides from Z. jujuba regulate anti-melanogenesis remains unclear. In this study, we evaluated the anti-melanogenic activity of five flavonoid glycosides from Z. jujuba var. inermis (Bunge) Rehder seeds, including jujuboside A (JUA), jujuboside B (JUB), epiceanothic acid (EPA), betulin (BTL), and 6’’’-feruloylspinosin (FRS), in B16F10 melanoma cells and zebrafish larvae. According to our results, JUB, EPA, and FRS potently inhibited α-melanocyte-stimulating hormone (α-MSH)-induced melanogenesis and prevented hyperpigmentation in zebrafish larvae. In particular, under α-MSH-stimulated conditions, FRS most significantly inhibited α-MSH-induced intracellular and extracellular melanin content in B16F10 melanoma cells. Additionally, JUB, EPS, and FRS remarkably downregulated melanogenesis in α-MSH-treated zebrafish larvae, with no significant change in heart rate. Neither JUA nor BTA were effective in downregulating melanogenesis in B16F10 melanoma cells and zebrafish larvae. Furthermore, JUB, EPA, and FRS directly inhibited in vitro mushroom tyrosinase enzyme activity. JUB, EPA, and FRS also downregulated cyclic adenosine monophosphate (cAMP) levels and the phosphorylation of cAMP-response element-binding protein (CREB), and subsequent microphthalmia transcription factor (MITF) and tyrosinase expression. In conclusion, this study demonstrated that JUB, EPA, and FRS isolated from Z. jujuba var. inermis (Bunge) Rehder seeds exhibit potent anti-melanogenic properties by inhibition of the cAMP-CERB-MITF axis and consequent tyrosinase activity.

Inhibitory effects and molecular mechanism on mushroom tyrosinase by condensed tannins isolation from the fruit of Ziziphus jujuba Mill. var. spinosa (Bunge) Hu ex H. F. Chow

The structure of extracted condensed tannin (CT) from the fruit of Sour jujube (Ziziphus jujuba Mill. var. spinosa (Bunge) Hu ex H. F. Chow) and the molecular mechanisms by which CT inhibits the activity of mushroom tyrosinase were investigated. The structure of CT was characterized by high performance liquid chromatography electrospray ionization mass spectrometry, and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. The kinetic assays were used to detect inhibition effect, type and mechanism. UV scanning, fluorescence quenching, copper interacting, o-quinone interaction and molecular docking assays were also used to reveal the molecular mechanisms by which CT inhibit tyrosinase. The results showed the structural units of CT containing afzelechin/epiafzelechin, catechin/epicatechin, and gallocatechin/epigallocatechin. Kinetic analysis showed that CT inhibits both the monophenolase and diphenolase activities of tyrosinase and exhibits reversible, mixed type mechanism. The fruit CT interacts primarily with the copper ions and specific amino acid residue (Asn191, Thr203, Ala202, Ser206, Met201, His194, His54, Glu182 and Ile42) in the active site of tyrosinase to disturb oxidation of substrates by tyrosinase. These results suggested the sour jujube fruit is a potential natural source of tyrosinase inhibitors, and has a potential to be used in food preservation, whitening cosmetics.

Identification wild and cultivated licorice by multidimensional analysis

Licorice is known as a botanical source in medicine and a sweetening agent in food products. Commercial licorice is from the source of wild and cultivated G. uralensis. It was recognized that the material basis of wild and cultivated licorice is different. This study systematically investigated the difference between them by multidimensional analysis technology. The results showed that the content of starch grain, total dietary fibre (TDF), and 11 secondary metabolite components was significantly different in wild and cultivated licorice. principal component analysis (PCA) and orthogonal partial least square (OPLS-DA) analyses showed that the wild and cultivated licorice samples could be clearly separated based on the acquired data of microscopic, macromolecular substance and secondary metabolite analysis. The main markers were starch grain, isoliquiritin apioside, liquirtin apioside and TDF. Additionally, NIR spectroscpy combined with PLS-DA has demonstrated a suitable, fast and nondestructive methodology for authentication of wild and cultivated licorice.

Bioactive compounds, antioxidant and antimicrobial activities of extracts from different plant parts of two Ziziphus Mill. species

Ziziphus lotus L. (Lam.) and Z. mauritiana Lam., as a widespread species in Tunisia, are well known for their medicinal and food uses. The aim of the present study was to screen the content of total polyphenols, flavonoids, and condensed tannins together with the radical scavenging capacity and the antimicrobial activity of leaves, fruits and seeds extracts of Z. lotus and Z. mauritiana from different localities. Results showed that leaves extracts presented the highest phenolic compounds content for both species. Furthermore, LC-ESI-MS analysis allowed the identification of 28 bioactive compounds regardless of species and organs, with the predominance of quinic acid and rutin. Leaves extract of Z. mauritiana possessed the highest total antioxidant capacity. The antimicrobial tests showed that leaves extracts of Z. mauritiana and Z. lotus from Oued Esseder exhibited the highest activity against four bacterial strains (Staphylococcus aureus, Listeria monocytogenes, Salmonella typhimurium and Escherichia coli). The main results showed that the studied species of Ziziphus genus are an excellent source of natural bioactive molecules that could be an interesting material for industrial and food purposes.

Quality Variation of Goji (Fruits of Lycium spp.) in China: A Comparative Morphological and Metabolomic Analysis

Goji (fruits of Lycium barbarum L. and L. chinense Mill.) has been used in China as food and medicine for millennia, and globally has been consumed increasingly as a healthy food. Ningxia, with a semi-arid climate, always had the reputation of producing best goji quality (daodi area). Recently, the increasing market demand pushed the cultivation into new regions with different climates. We therefore ask: How does goji quality differ among production areas of various climatic regions? Historical records are used to trace the spread of goji production in China over time. Quality measurements of 51 samples were correlated with the four main production areas in China: monsoon (Hebei), semi-arid (Ningxia, Gansu, and Inner Mongolia), plateau (Qinghai) and arid regions (Xinjiang). We include morphological characteristics, sugar and polysaccharide content, antioxidant activity, and metabolomic profiling to compare goji among climatic regions. Goji cultivation probably began in the East (Hebei) of China around 100 CE and later shifted westward to the semi-arid regions. Goji from monsoon, plateau and arid regions differ according to its fruit morphology, whereas semi-arid goji cannot be separated from the other regions. L. chinense fruits, which are exclusively cultivated in Hebei (monsoon), are significantly lighter, smaller and brighter in color, while the heaviest and largest fruits (L. barbarum) stem from the plateau. The metabolomic profiling separates the two species but not the regions of cultivation. Lycium chinense and samples from the semi-arid regions have significantly (p < 0.01) lower sugar contents and L. chinense shows the highest antioxidant activity. Our results do not justify superiority of a specific production area over other areas. Instead it will be essential to distinguish goji from different regions based on the specific morphological and chemical traits with the aim to understand what its intended uses are.