Composition Analysis and Nutritional Value Evaluation of Amino Acids in the Fruit of 161 Jujube Cultivars.

Amino acids are an essential group of compounds involved in protein synthesis and various metabolic and immune reactions in the human body. Chinese jujubes (Ziziphus jujuba Mill.) are an important fruit and medicinal plant which are native to China and have been introduced into around 50 countries. However, systematic research on the composition and content diversity of amino acids in the jujube is still lacking. In this experiment, the amino acid composition and the contents of the dominant amino acids in the fruit of 161 cultivars of jujube were determined by HPLC. Of the twenty-one kinds of amino acids detected, a total of fourteen kinds of amino acids were detected, of which eight kinds of amino acids were relatively high, including five essential amino acids (threonine, valine, isoleucine, leucine, and phenylalanine) and three nonessential amino acids (glycine, alanine, and proline). However, the contents of the remaining six amino acids were relatively low (aspartic acid, glutamic acid, histidine, serine, arginine, and tryptophan). Therefore, the eight primary amino acids were used as the index to evaluate the amino acids of 161 jujube varieties. Proline accounts for 56.8% of the total amino acid content among the eight amino acids. The total content of the eight primary amino acids in most jujube varieties was 1-1.5 g/100 g, and the highest content of 'Zaoqiangmalianzao' was 2.356 g/100 g. The average content of proline was 6.01-14.84 times that of the other seven amino acids. According to the WHO/FAO revised model spectrum of ideal essential amino acids for humans, 19 cultivars met the E/T (essential amino acids/total amino acids) standard, and their values ranged from 35% to 45%; 12 cultivars meet E/NE (non-essential amino acids) ≥ 60%. All cultivars reached the requirement of BC (branched-chain amino acids)/E ≥ 40% with 15 cultivars over 68%. One hundred and fifty-seven cultivars reach the standard of BC/A (aromatic amino acids) ≈ 3.0~3.5. The amino acid ratio coefficient analysis showed that phenylalanine was the first limiting amino acid of all the jujube cultivars. The SRC (the score of amino acid ratio coefficient) values of 134 cultivars were between 50% and 70%, with 12 cultivars over 70%, indicating that jujube fruits are of high nutritional value in terms of amino acids. Based on the principal component analysis and comprehensive ranking of amino acid nutritional value, the top five cultivars were screened from the 161 ones tested, i.e., 'Tengzhouchanghongzao', 'Xinzhengxiaoyuanzao', 'Hanguowudeng', 'Xuputiansuanzao', and 'Lichengxiaozao'. This study established, firstly, a complete basic data analysis of amino acid content in jujube fruit which could be used to select germplasm resources suitable for developing functional amino acid food, and provide theoretical support for the high value utilization of amino acids in jujubes.

Spatial and Temporal Distribution of Phenolic and Flavonoid Compounds in Sour Jujube (Ziziphus. Acidojujuba Cheng et Liu) and Their Antioxidant Activities.

In order to comprehensively analyze the antioxidant substances in sour jujube, total phenolic content (TPC) and total flavonoids contents (TFC) in different organs, including stem, leaf, flower, fruit pulp, and seed were analyzed for their contents and antioxidant activities. The results showed that leaves possessed significantly higher TPC and TFC (20.4 and 20.5 mg/g, respectively) than the other organs and have the highest antioxidant activity, which were also higher than the wild blueberry (A well-known for its high TPC). Subsequently, the variations in the antioxidant content and antioxidant activity of leaves were analyzed during leaf development. TPC in leaves sampled in may and august were significantly higher than that in other months, while the highest one was found in may. The n-hexane, ethyl acetate, n-butanol, and water fractions obtained from the main methanol extract of sour jujube leaves were evaluated for TPC and TFC and their antioxidant activity and it was found that ethyl acetate fraction displayed the highest TPC and TFC (184.5 and 193.3 mg/g, respectively), as well as the best antioxidant activity. In addition, using LC-MS and HPLC, ethyl acetate fraction was analyzed from qualitative and quantitative aspects; 31-one phenolic compounds, including catechin (33.0 mg/g), epigallocatechin (15.3 mg/g), quercetin 3-O-glucoside (11.4 mg/g), naringenin (6.7 mg/g), esculetin (4.8 mg/g), and chlorogenic acid (4.6 mg/g) were identified. Catechin, esculetin, epigallocatechin, chlorogenic acid, quercetin 3-O-glucoside, and naringenin exhibited high antioxidant activity. These results provide a theoretical basis for further study and utilization of flavonoid and polyphenols in sour jujube.

[Electroacupuncture of "Shangjuxu"(ST37) and "Tianshu"(ST25) reduces colonic injury by suppressing NF-κB/NLRP3 signaling in rats with ulcerative colitis].

OBJECTIVE: To observe the effect of electroacupuncture (EA) of "Shangjuxu"(ST37) and "Tianshu"(ST25) on colonic mucosal injury and activities of nuclear factor-κB (NF-κB)/Nod-like receptor family，pyrin domain-containing 3 (NLRP3) inflammasome signaling in the colonic tissue in rats with ulcerative colitis (UC), so as to explore its mechanisms underlying improvement of UC. METHODS: Male SD rats were randomly divided into blank, model, medication and EA groups, with 12 rats in each group. The UC model was established by enema of 2-4-6 trinitrobenzene sulfonic acid +50% ethanol (2.5 mL). EA (10 Hz/50 Hz) was applied to bilateral ST37 and ST25 for 20 min, once a day, for a total of 10 days. Rats of the medication group received gavage of mesalazine suspension (2 mL：0.2 g/kg+0.9% saline) once a day, for 10 days. The rats' general conditions were recorded for calculating the disease activity index (DAI) score (0-4 points). The colonic tissue was sampled for giving colonic mucosa damage index (CMDI, 0-5 points) score and for observing histopathological changes after hematoxylin-eosin (HE) staining, and for detecting expression levels of NF-κB and NLRP3 by using immunohistochemistry and Western blot, separately. The contents of serum interleukin-1ß (IL-1ß), NLRP3 and tumor necrosis factor-α (TNF-α) were detected by enzyme-linked immunosorbent assay. RESULTS: Compared with the blank group, the DAI and CMDI scores, contents of serum IL-1ß, NLRP3, and TNF-α, as well as the immunoactivity and expression of NF-κB and NLRP3 proteins were significantly increased in the model group (P<0.05). Relevant to the model group, modeling-induced increases of DAI and CMDI scores, serum IL-1ß, NLRP3 and TNF-α contents, and NF-κB and NLRP3 expression were reversed in both medication and EA groups (P<0.05), the effect of EA was apparently superior to that of mesalazine in down-regulating CMDI score and serum IL-1ß level (P<0.05). No significant diffe-rences were found between the medication and EA groups in down-regulating DAI score, serum TNF-α and NLRP3 contents, and expression of NF-κB and NLRP3 proteins (P>0.05). The rats' general conditions including arch back sloth, anorexia, loss of fur gloss, weight loss, lethargy and loose of stool, and histopathological changes such as necrosis of intestinal mucosa, formation of obvious ulcerative surface, with many neutrophils and pus cells and inflammatory cell infiltration were obvious in the model group, which were relative milder in both medication and EA groups. CONCLUSION: EA can relieve colonic injury in UC rats, which may be related to its functions in down-regulating serum IL-1ß, TNF-α and NLRP3 levels by suppressing colonic NF-κB / NLRP3 inflammasome signaling.

Evaluation of Cholinesterase Inhibitory Potential of Different Genotypes of Ziziphus nummularia, Their HPLC-UV, and Molecular Docking Analysis.

Ziziphus nummularia is an important source of valuable phytoconstituents, which are widely used in traditional medicine system of Indo-Pak sub-continent. In this study we investigated the distribution of phenolic compounds in the fruit pericarps of six different genotypes (ZNP01-06) of Z. nummularia growing in the unexplored hilly areas of Pakistan. The methanolic extracts of these genotypes were screened for total phenolic content (TPC), total flavonoid content (TFC), antioxidant, and cholinesterase inhibitory potentials. The observed biological potentials were explained in terms of the outcome of molecular docking and HPLC analyses. Among them, genotype ZNP02 displayed high TPC (88.50 ± 1.23 µg/mL) and showed potent scavenging activity against DPPH (67.03 ± 1.04 µg/mL) and ABTS (65.3 ± 1.74 µg/mL) in comparison to ascorbic acid (68.7 ± 0.47 µg/mL). Moreover, genotypes ZNP01, ZNP02, and ZNP04 displayed potent inhibition against acetyl and butyryl cholinesterases (AChE and BChE) with IC50 values of 21.2, 20.5, and 23.7 µg/mL (AChE) and 22.7, 24.4, and 33.1 µg/mL (BChE), respectively. Furthermore, the individual compounds in the most potent species ZNP01 responsible for potent enzyme inhibition (identified through HPLC-UV analysis), were computed via docking simulation software to the enzyme structures. Among these compounds rutin exhibited significant binding affinity with value of -9.20 kcal/mol. The differences amongst the phytochemical compositions of the selected genotypes highlighted the genotypic variations in them. Based on our results it was concluded that the selected plant can be used as remedy of oxidative stress and neurodegenerative diseases. However, further studies are needed to isolate responsible compounds and test the observed potential in vivo, along with toxicological evaluations in animal models.

The effect of deep eutectic solvent on the pharmacokinetics of salvianolic acid B in rats and its acute toxicity test.

Deep eutectic solvent (DES), the benign green solvent with uniquely physical properties, has been widely applied in various fields. Our previous study indicated that DES could improve the stability and extraction efficiency of salvianolic acid B (SAB). In this work, with SAB as a model drug, the feasibility of DES as a drug carrier for oral preparation was investigated by evaluating the influence of DES on the pharmacokinetics of SAB and the toxicity of DES. Acute oral toxicity test illustrated that choline chloride-glycerol (ChCl-GL, molar ratio 1:2) was non-toxic with the median lethal dose of 7733mg/kg. To comparison the difference of pharmacokinetics between SAB dissolved in ChCl-GL (1:2) and in water, a rapid and sensitive ultra-performance liquid chromatography coupled with mass spectrum was established to determine SAB and its metabolites in rat plasma. The method validation was also tested for the specificity, linearity (r2>0.9980 over two orders of magnitude), precision (intra-day relative standard deviation (RSD)<2.73% and inter-day RSD<7.72%), extraction recovery (70.96-80.78%) and stability under three different situations. Compared to water, the pharmacokinetic parameters clarified that ChCl-GL (1:2) could promote the absorption of SAB, the peak concentration (Cmax) of 0.308±0.020mg/L was slightly higher than 0.277±0.024mg/L (SAB dissolved in water), and the peak time (Tmax) was significantly decreased from 30min (SAB dissolved in water) to 20min. There was no significant difference on the metabolites between SAB dissolved in ChCl-GL (1:2) and in water. This is the first report on the pharmacokinetic study of DES as a candidate of drug carrier, and the results provide a meaningful basis for the application of DES in pharmaceutical preparation.

Deep Eutectic Solvent-Based Microwave-Assisted Method for Extraction of Hydrophilic and Hydrophobic Components from Radix Salviae miltiorrhizae.

Deep eutectic solvents (DESs) have attracted significant attention as a promising green media. In this work, twenty-five kinds of benign choline chloride-based DESs with microwave-assisted methods were applied to quickly extract active components from Radix Salviae miltiorrhizae. The extraction factors, including temperature, time, power of microwave, and solid/liquid ratio, were investigated systematically by response surface methodology. The hydrophilic and hydrophobic ingredients were extracted simultaneously under the optimized conditions: 20 vol% of water in choline chloride/1,2-propanediol (1:1, molar ratio) as solvent, microwave power of 800 W, temperature at 70 °C, time at 11.11 min, and solid/liquid ratio of 0.007 g·mL-1. The extraction yield was comparable to, or even better than, conventional methods with organic solvents. The microstructure alteration of samples before and after extraction was also investigated. The method validation was tested as the linearity of analytes (r² > 0.9997 over two orders of magnitude), precision (intra-day relative standard deviation (RSD) < 2.49 and inter-day RSD < 2.96), and accuracy (recoveries ranging from 95.04% to 99.93%). The proposed DESs combined with the microwave-assisted method provided a prominent advantage for fast and efficient extraction of active components, and DESs could be extended as solvents to extract and analyze complex environmental and pharmaceutical samples.

The complex jujube genome provides insights into fruit tree biology.

The jujube (Ziziphus jujuba Mill.), a member of family Rhamnaceae, is a major dry fruit and a traditional herbal medicine for more than one billion people. Here we present a high-quality sequence for the complex jujube genome, the first genome sequence of Rhamnaceae, using an integrated strategy. The final assembly spans 437.65 Mb (98.6% of the estimated) with 321.45 Mb anchored to the 12 pseudo-chromosomes and contains 32,808 genes. The jujube genome has undergone frequent inter-chromosome fusions and segmental duplications, but no recent whole-genome duplication. Further analyses of the jujube-specific genes and transcriptome data from 15 tissues reveal the molecular mechanisms underlying some specific properties of the jujube. Its high vitamin C content can be attributed to a unique high level expression of genes involved in both biosynthesis and regeneration. Our study provides insights into jujube-specific biology and valuable genomic resources for the improvement of Rhamnaceae plants and other fruit trees.

[Structure identification of jujuboside D].

AIM: To study the chemical constituents of Ziziphus jujuba Mill var. Spinosa (Bunge) Hu ex. H. F. Chou. METHODS: To separate the constituents by using various kinds of chromatography and identify their structures on the basis of spectral analysis. RESULTS: Five compounds were isolated and their structures were established as jujuboside D (1), jujuboside A (2), 5,7,4'-trihydroxyflavonol-3-O-beta-D-rhamnopyranosyl-(1-->6)-beta-D-glucopyranoside (3), 6'''-coumaroylspinosin (4) and phenylalanine (5). CONCLUSION: Compound 1 is a new compound named jujuboside D, 4 is reported as rotamer for the first time, 3 and 5 isolated from this plant for the first time.