Changes in pectin characteristics of jujube fruits cv "Dongzao" and "Jinsixiaozao" during cold storage.

Softening is one of the main factors affecting market value and consumer preferences for jujubes, and it was closely related to the modification and depolymerization of pectin. Changes in characteristics of three pectins (water-soluble pectin (WSP), sodium carbonate-soluble pectin (SSP) and chelate-soluble pectin (CSP)), including their contents, degree of methylesterification (DM), neutral sugar compositions, the molecular weight (Mw ) distributions and nanostructures, from two jujube fruits cv Dongzao (DZ) and Jinsixiaozao (JS) during cold storage were assessed. The results showed that variation in pectin characteristics during cold storage was similar between DZ and JS. The reduction of firmness corresponded to a conversion of water-insoluble pectin to WSP during cold storage. DM of WSP presented an increase trend in the late storage. Rhamnose (Rha), arabinose (Ara) and glucose (Glc) were the crucial compositions in three pectins, and most neutral sugar compositions in three pectins first increased and then decreased during cold storage. Changes in the ratio of (galactose (Gal)+Ara)/Rha and Ara/Gal represented that the branch chains of rhamnogalacturonan-I in three pectins depolymerized after storage. The high Mw in WSP and SSP of jujubes were solubilized and extensively depolymerized into pectin with lower Mw after storage. AFM images showed an increase in short chains and branch structures of three pectins after storage. Overall, three pectins in DZ and JS depolymerized and solubilized during cold storage. WSP and SSP were more contributed to the softening of jujubes compared to CSP, and they played the critical role for regulating the softening of jujube fruits during cold storage. PRACTICAL APPLICATION: Softening is one of the main factors affecting market value and consumer preferences for jujubes, and it was closely related to the modification and depolymerization of pectin. Changes in characteristics of three pectins (WSP, SSP, CSP), including their contents, degree of methylesterification, neutral sugar compositions, the molecular weight distributions and nanostructures, from two jujube fruits cv Dongzao (DZ) and Jinsixiaozao (JS) during cold storage were assessed. Three pectins in DZ and JS depolymerized and solubilized during cold storage. WSP and SSP were more contributed to the softening of jujubes compared to CSP, and they played the critical role for regulating the softening of jujube fruits during cold storage. This study would elucidate the mechanism of jujube softening and help to regulate the postharvest quality during cold storage.

Phytochemical Profiling and Fingerprint Analysis of Chinese Jujube (Ziziphus jujuba Mill.) Leaves of 66 Cultivars from Xinjiang Province.

Foliage of jujube (Ziziphus jujuba Mill.) as a byproduct of agriculture, is a traditional nutraceutical material in China. Previous studies have shown that it is a rich resource of polyphenols. However, information on its complete phenolic profile and the difference between cultivars is still limited. This study investigated and compared phytochemical profiles of leaves of 66 Chinese jujube cultivars. Forty-two compounds, including 22 flavonols, two flavanols, one flavanone, 13 derivatives of phenolic acids, three simple acids, and one unknown hexoside were identified/tentatively identified using high-performance liquid chromatography (HPLC) coupled with high-resolution mass spectrometry. Eight major flavonols were quantified by HPLC coupled with an ultraviolet (UV) detector. The contents of total flavonoids ranged from 2.6-25.1 mg/g dry weight (DW). Differences between cultivars were analyzed by hierarchical cluster analysis (HCA) and principal component analysis (PCA). This study presents a systematic study on the phenolic compounds in Chinese jujube leaves of different cultivars.

Ziziphus spinosa seeds for insomnia: A review of chemistry and psychopharmacology.

BACKGROUND: In Chinese medicine, Ziziphus jujuba Mill. var. spinosa (Bunge) Hu ex H. F. Chou is widely used for the treatment of insomnia. PURPOSE/SECTIONS: This paper summarises the chemistry, psychopharmacology, and compares the pharmaceutical effects of the seeds of Ziziphus jujuba plant, Ziziphus spinosa (ZS) seeds, with benzodiazepines. Whole extracts and constituent compounds have been evaluated in preclinical and clinical studies. CONCLUSIONS: ZS secondary metabolites modulate GABAergic activity and the serotonergic system. The actual therapeutic agents require further confirmation/identification so that new insomnia phytomedicines can be discovered.

[Species differentiation and quality assessment of Ziziphus jujuba var. spinosa based on the HPLC fingerprint and quantitative analysis].

OBJECTIVE: To establish an HPLC method of a characteristical chemical fingerprint analysis in combination with simultaneous determination of four bioactive components for species differentiation and quality assessment of Ziziphus jujuba var. spinosa. METHODS: The chromatographic separation was performed on an Agilent TC-C18 BDS (250 mm x 4.6 mm, 5 microm) column. The mobile phase consisted of acetonitrile and water in a linear gradient elution procedure. The evaporator tube temperature of ELSD was set at 110.5 degrees C with the nebulizing gas flow rate of 3.1 mL/min and the flow rate of mobile phase was 1.0 mL/min. The column was maintained at 30 degrees C. The injection volume was 20 microL. RESULTS: HPLC methodology for both chemical fingerprint analysis and quantitative determination of four active ingredients were validated, respectively. According to the contents of the four ingredients and the chemical fingerprints of Ziziphus jujuba var. spinosa using principal component analysis, Ziziphus jujuba var. spinosa was different from the fake derived from the seeds of Ziziphus mauritiana. CONCLUSION: The developed HPLC method is exclusive and repetitive for the species identification and quality evaluation of Ziziphus jujuba var. spinosa.

Chemotaxonomic variability in Zizyphus mouritiana varieties and its pharmacological properties in relation to human health.

Twenty varieties of ber (Zizyphus mouritiana), namely umaran, katha, bilayati, kaithli, ZG-3, gola, safeda rohtak, takadi, tikari, banarasi karaka, seo, sonaur-2, sonaur-3, ilaichi, mundia murahra, pathan, kakrola gola, seb, golden yellow and chhuhara, were investigated for the presence of phenolic acids in stem bark, leaves and fruits using high performance liquid chromatograph. Results indicated the presence of tannic (retention time (Rt.) 2.76 min), gallic (Rt. 2.86 min), caffeic (Rt. 3.12 min), vanillic (Rt. 3.26 min), ferulic (Rt. 3.42 min), chlorogenic (Rt. 4.16 min) and cinnamic acids (Rt. 4.45 min) in varying amounts in different parts in of these varieties. In fruits of seven varieties, namely, kaithly, sonaur-2, sonaur-3, mundia murahra, pathan, golden yellow and chhuhara, oxalic acid (Rt. 3.00 min) was also detected. Pharmacological properties of phenolic acids of fruits in relation to human health and the possible implications of different phenolic acids in chemotaxonomy of different varieties of ber are discussed.

[Studies on HPLC-FPS of the saponins from Semen Ziziphi Spinosae].

OBJECTIVE: To establish a method of HPLC-fingerprint spectrum (HPLC-FPS) for the active part in Semen Ziziphi Spinosae (SZS) in order to control the quality of SZS from different places. METHODS: The gradient elution mode was applied in chromatographic separation, and data were analysed by" Similarity Evaluation software" to compare the HPLC-FPS of SZS from different places. RESULTS: The conditions for HPLC analysis of SZS were established and the FPS of samples from different habitats showed some differences. CONCLUSION: All components in the spectrum were separated well and the HPLC fingerprint method is repeatable. The method can be used in quality assessment of SZS.