Quantitative assessment of bioactive compounds and the antioxidant activity of 15 jujube cultivars

UPLC-Q-TOF-MS/MS identification, antioxidant, and alpha-glucosidase inhibition activities of three forms of phenolic compounds from Yemeni jujube fruit: In vitro and in silico investigations

Jujube fruits have rich medicinal value due to their biological properties which are affected mainly by geographical locations. This study investigates the antioxidant properties of free fraction (FF), esterified fraction (EF), bound fraction (BF), and other metabolites prepared from dried Yemeni jujube fruit and compare to those previously reported in the literature. Results from UPLC-Q-TOF-MS/MS analysis showed that this fruit consists of a total of 33, 26, and 27 free, esterified, and bound compounds identified, respectively. In terms of ABTS, DPPH, FRAP, and H2O2 assays, the BF exhibited values 1.2, 1.3,1.3, and 1.4 times higher than those of the FF, and similarly, 1.8, 1.9,2.0, and 2.5 times higher than the EF. A similar trend was observed in the inhibition of α-glucosidase (α-Glu), where the BF was 1.6, and 2.4 times more effective compared to the FF and EF, respectively. In silico analysis showed that flavonoids, the key active compounds, had substantial α-glucosidase binding capacity. In the meat model, all fractions inhibited protein and lipid oxidation during storage, and the BF exhibited the highest antioxidant capacity. This study provides the first investigation of the structure of active compounds and their biological properties in Yemeni jujube fruit. Yemeni fruits can be utilized as natural antioxidants, and nutraceuticals in food preservation, and medicine respectively.

Four new phenolic compounds from stems and leaves of Hemerocallis citrina (Daylily)

Four new phenolic compounds, hemerodiphenylethanes A-D (1-4), along with eight known compounds methyl 2,4-dihydroxy-6-[2-(4-hydroxyphenyl) ethyl] benzoate (5), methyl 2,4-dihydroxy-6-(4-hydroxyphenethyl)-3-methylbenzoate (6), neochlorogenic acid (7), isoquercetin (8), isorhamnetin-3-O-β-D-galactoside (9), velutin (10), rutin (11), and (+)-syringaresinol (12), were isolated from the stems and leaves of Hemerocallis citrina Baroni (Daylily). Their structures were elucidated based on HR-ESI-MS, 1D- and 2D-NMR spectra, and ECD calculations. Among them, both compounds 10 and 12 were isolated from the genus Hemerocallis, and compounds 5 and 6 were isolated from this plant species for the first time. These compounds showed antioxidant activity as determined by IC50 values of DPPH and ABTS+ in a radical scavenging experiment.

Exploring the wound-healing potential and seasonal chemical variability of the Formosan Callery pear Pyrus calleryana: implications for therapeutic applications

CONTEXT

Pyrus calleryana Decne (Rosaceae), renowned for its therapeutic properties, is known to moisturize the lungs (removing dryness; relieving cough), clear heat (acting as an antipyretic; febrifuge) and aid in detoxification (relieving pyogenic inflammation; eliminating toxins). However, scientific evidence supporting its efficacy in wound healing is lacking.

OBJECTIVE

This study investigated P. calleryana samples collected over a year to explore metabolite variations and their impact on skin wound-healing activities.

MATERIALS AND METHODS

P. calleryana (PC) twigs and leaves were collected from the Matsu Islands, Taiwan, spanning 2018-2020. Extracts were prepared using 95% ethanol or water, and we assessed the chemical composition, total phenolic/triterpenoid contents and antioxidant properties. Metabolites were analysed via LC-MS/MS and molecular networking. Wound healing potential was evaluated on WS-1 cells through MTT and migration assays, and gene expression analyses, with tests including control (DMSO), compounds 1 (3'-hydroxylbenzyl-4-hydroxybenzoate-4'-O-β-glucopyranoside) and 2 (vanilloylcalleryanin) (100 µM), and a positive control (ascorbic acid, 100 µM) for 24 h.

RESULTS

Significant variations in extract compositions were observed based on the solvent used, with distinct metabolomic profiles in extracts collected during different months. Notably, compounds 1 and 2 showed no cytotoxic effects on human dermal fibroblast cells and significantly accelerated wound closure at 100 μM. A gene expression analysis indicated upregulation of wound healing-associated genes, including MMP-1 (matrix metalloproteinase-1) and COL1A1 (collagen, type 1, alpha 1).

CONCLUSIONS

This study reports the first evidence of PC compounds aiding wound healing. Utilizing Global Natural Products Social Molecular Networking (GNPS) and principal component analysis (PCA) approaches, we unveiled metabolomic profiles, suggesting the potential to expedite wound-healing.

Characteristic Polyphenols in 15 Varieties of Chinese Jujubes Based on Metabolomics

BACKGROUND

Jujube is a homologous herb of medicine and food, and polyphenols are key in determining the functional effects of jujubes.

METHODS

In this study, characteristic polyphenols in 15 varieties of Chinese jujubes were investigated based on untargeted metabolomics.

RESULTS

The results showed that a total of 79 characteristic polyphenols were identified in the 15 varieties of Chinese jujube, and 55 characteristic polyphenols such as syringetin, spinosin and kaempferol were reported for the first time. Scopoletin (63.94% in LZYZ), pectolinarin (22.63% in HZ) and taxifolin (19.69% in HZ) contributed greatly and presented significant (p < 0.05) differences in the 15 varieties of Chinese jujubes. HZ was characterized by pectolinarin, erianin and wogonoside, while XSHZ, NYDZ and RQHZ, with similar polyphenol profiles, were characterized by (+)-catechin, combretastatin A4 and tectorigenin. JSBZ, HMDZ, TZ, JCJZ and HPZ had similar polyphenol profiles of galangin, isoferulic acid and hydroxysafflor yellow A.

CONCLUSIONS

Metabolomics is critical in grasping the full polyphenol contents of jujubes, and the differences in the polyphenol profiles and characteristic individual polyphenols of the 15 varieties of Chinese jujubes were well analyzed by principal component analysis (PCA).

In vitro digestion and fermentation characteristics of soluble dietary fiber from adlay (Coix lacryma-jobi L. var. ma-yuen Staft) bran modified by steam explosion

Adlay bran is known for its nutrient-rich profile and multifunctional properties, and steam explosion (SE) is an emerging physical modification technique. However, the specific effects of SE on the activity composition and antioxidant capacity of adlay bran soluble dietary fiber (SDF) during in vitro digestion, as well as its influence on gut microbiota during in vitro fermentation, remain inadequately understood. This paper reports the in vitro digestion and fermentation characteristics of soluble dietary fiber from adlay bran modified by SE (SE-SDF). Compared with the untreated samples (0-SDF), most of the phenolic compounds and antioxidant capacity were significantly increased in the SE-SDF digests. Additionally, SE was beneficial for adlay bran SDF to increase the content of acetic acid, propionic acid and total short-chain fatty acids (SCFAs) in fermentation broth during in vitro fermentation. SE-SDF could promote the growth of beneficial bacteria while inhibiting the proliferation of pathogenic microbes. Our research indicates that SE-SDF shows strong antioxidant properties after in vitro digestion and plays a pivotal role in regulating gut microbiota during in vitro fermentation, ultimately enhancing human intestinal health.

Functional Nutrients and Jujube-Based Processed Products in Ziziphus jujuba

Jujube (Ziziphus jujuba Mill.) is the first tree species in China, with a long history and abundant yield. However, fresh jujubes have a short shelf-life and are not resistant to storage. Therefore, more and more processed jujube products are being studied. These processed products can extend the shelf-life of jujubes and attract widespread attention for their rich functional nutrients. This review summarized changes in nutrients of fresh jujube and processed products and the research progress of different preparation methods of jujubes. Meanwhile, the pharmacological effects of bioactive components in jujube-based products were concluded. Jujube and its processed products contain rich polysaccharides, vitamin C, and other functional nutrients, which are beneficial to humans. As the initial processing method for jujubes, vacuum freezing or microwave drying have become the most commonly used and efficient drying methods. Additionally, processed jujube products cannot be separated from the maximum retention of nutrients and innovation of flavor. Fermentation is the main deep-processing method with broad development potential. In the future, chemical components and toxicological evaluation need to be combined with research to bring consumers higher quality functional jujube products and ensure the sustainable development of the jujube industry.

Investigation of bioactive compounds and their correlation with the antioxidant capacity in different functional vinegars

There are complex and diverse substances in traditional vinegars, some of which have been identified as biologically active factors, but the variety of functional compounds is currently restricted. In this study, it was aimed to determine the bioactive compounds in 10 typical functional vinegars. The findings shown that total flavonoids (0.21-7.19 mg rutin equivalent/mL), total phenolics (0.36-3.20 mg gallic acid equivalent/mL), and antioxidant activities (DPPH: 3.17-47.63 mmol trolox equivalent/L, ABTS: 6.85-178.29 mmol trolox equivalent/L) varied among different functional vinegars. In addition, the concentrations of the polysaccharides (1.17-44.87 mg glucose equivalent/mL) and total saponins (0.67-12.46 mg oleanic acid equivalent/mL) were determined, which might play key role for the function of tested vinegars. A total of 8 organic acids, 7 polyphenol compounds and 124 volatile compounds were measured and tentatively identified. The protocatechuic acid (4.81-485.72 mg/L), chlorogenic acid (2.69-7.52 mg/L), and epicatechin (1.18-97.42 mg/L) were important polyphenol compounds in the functional vinegars. Redundancy analysis indicated that tartaric acid, oxalic acid and chlorogenic acid were significantly positively correlated with antioxidant capacity. Various physiologically active ingredients including cyclo (Pro-Leu), cyclo (Phe-Pro), cyclo (Phe-Val), cyclo (Pro-Val), 1-monopalmitin and 1-eicosanol were firstly detected in functional vinegars. Principle component analysis revealed that volatiles profile of bergamot Monascus aromatic vinegar and Hengshun honey vinegar exhibited distinctive differences from other eight vinegar samples. Moreover, the partial least squares regression analysis demonstrated that 11 volatile compounds were positively correlated with the antioxidant activity of vinegars, which suggested these compounds might be important functional substances in tested vinegars. This study explored several new functionally active compounds in different functional vinegars, which could widen the knowledge of bioactive factor in vinegars and provide new ideas for further development of functional vinegar beverages.

The Flavor Characteristics and Metabolites of Three Commercial Dried Jujube Cultivars

To understand the flavor and metabolite differences between the three commercial dried jujube cultivars Huizao (HZ), Hamazao 1 (HMZ), and Qiyuexian (QYX), their soluble sugars, organic acids, volatiles, and metabolites were systematically investigated. The results show that sucrose and malic acid were the main soluble sugar and organic acids contained in these dried jujubes, respectively. Sucrose (573.89 mg/g DW) had the highest presence in HZ, and the total sugar content (898.33 mg/g DW) was the highest in QYX. Both of these had a low total acid content, resulting in relatively high sugar-acid ratios (105.49 and 127.86, respectively) compared to that of HMZ (51.50). Additionally, 66 volatile components were detected in the 3 jujubes. These mainly included acids, aldehydes, esters, and ketones (90.5-96.49%). Among them, (E)-2-nonenal, (E)-2-decenal, heptanal, decanal, nonanal, and octanal were identified as the key aromatic substances of the dried jujubes, and their contents were the highest in HMZ. Moreover, 454 metabolites were identified, including alkaloids, amino acids, flavonoids, lipids, nucleotides, and terpenoids. The highest contents of flavonoids (5.6%) and lipids (24.9%) were detected in HMZ, the highest contents of nucleotides (10.2%) and alkaloids (27%) were found in QYX, and the contents of saccharides (5.7%) and amino acids (23.6%) were high in HZ. Overall, HZ, HMZ, and QYX significantly differ in their flavor and nutrition. HZ tastes better, HMZ is more fragrant, and QYX and HMZ possess higher nutritional values.

The effects of blueberry (Vaccinium corymbosum L.) and jujube fruit (Ziziphus jujube) on physicochemical, functional, and sensorial properties, and probiotic (Lactobacillus acidophilusDSM 20079) viability of probiotic ice cream

The effects of blueberry (BB) and jujube fruit (JF) on the quality parameters, functional, probiotic (Lactobacillus acidophilus DSM 20079) viability, and sensorial properties of probiotic ice cream were investigated. No statistical differences were discovered regarding titratable acidity and L. acidophilus DSM 20079 counts between all samples. However, the ice creams preserved the survivability of probiotic bacteria during the storage period. The probiotic ice creams had counts of viable L. acidophilus DSM 20079 ranging from 8.42 to 8.80 log CFU/g which met the minimum required to achieve probiotic effects after 60 days of storage. Probiotic ice cream with BB or JF had significantly lower L* values than the control, and the BB addition caused the greatest decrease. The addition of both fruits clearly enhanced the total phenolic content and antioxidative activity in ice cream. The incorporation of BB or JF into the ice creams did not statistically affect the overrun value, while the addition of both fruits dramatically affected the first dripping time and increased hardness. Overall, sensory attributes were not significantly altered by the fortification of either fruit relative to the control, so these fruits can be added at higher concentrations to ice cream formulations for further studies.

Development of a polyphenol-enriched whole kiwifruit dietary supplement and its potential in ameliorating hyperlipidemia

BACKGROUND

Kiwifruit pomace, which contains abundant phenolic compounds, is typically discarded during the juicing process, leading to wastage of valuable resources. To address this issue, various indicators (including total acidity, sugar/acid ratio, vitamin C, total polyphenols, polyphenol monomers, and soluble solids content) of 15 kiwifruit cultivars were evaluated and juiced. Then, a polyphenol-concentrated solution from kiwifruit pomace was backfilled into kiwi juice to prepare whole nutritious compound kiwi juice, and its anti-hyperlipidemic activity on obese model mice was then investigated.

RESULTS

Through grey relational analysis and the technique for order preference by similarity to an ideal solution (TOPSIS), Kuimi and Huayou were identified as the predominant varieties for juicing, with weighted relevance scores of 0.695 and 0.871 respectively and TOPSIS scores of 0.6509 and 0.8220 respectively. The polyphenol content of Cuixiang pomace was 43.97 mg g-1 , making it the most suitable choice for polyphenol extraction. By backfilling a polyphenol-concentrated solution derived from Cuixiang pomace into compound kiwi juice of Huayou and Kuimi, the whole nutritious compound kiwi juice with polyphenols was produced and exhibited superior bioactivities, including enhanced hepatic oxidative stress defense, and alleviated serum lipid abnormalities. Furthermore, whole nutritious compound kiwi juice with polyphenols ameliorated host intestinal microbiota dysbiosis by increasing the relative abundance of the phyla Bacteroidota and Verrucomicrobiota.

CONCLUSION

A hypolipidemic dietary supplement based on kiwifruit pomace polyphenols has been successfully developed, providing an effective solution for hyperlipidemia intervention. © 2023 Society of Chemical Industry.

A Literature Review of the Pharmacological Effects of Jujube

Jujube is a plant native to China that could be used in medicine and food. Its dried fruit is a superior herb commonly used in traditional Chinese medicine formulations for its calming effect and for nourishing the blood and strengthening the spleen and stomach. Jujube contains numerous active components including polysaccharides, phenols, and triterpene acids, which show a diverse array of pharmacological activities such as neuroprotection and the prevention and treatment of cardiovascular diseases. In this paper, the research status of jujube over the past two decades has been statistically evaluated. Meanwhile, by tracking the latest research advances, the pharmacological efficacy and molecular mechanisms of jujube are exhaustively expounded to provide specific and systematic references for further research on the pharmacological effects of jujube and its application in the food and pharmaceutical industries.

Transcriptome Characterization of Pigment-Related Genes in Jujube (Ziziphus Jujuba Mill.) Peel at Different Growth Stages

One of the most important qualities of jujube fruit is its color. Chlorophyll, carotenoid, and anthocyanin all play important roles in the coloring of jujube fruit. However, few studies have focused on the pigment molecular mechanism. In the present study, jujube peels of 'Sanbianhong' in three growth stages were evaluated for their gene expression characteristics and gene regulation related to pigment formation using the transcriptome sequencing analysis. A total of 84.86 Gb of clean data were obtained in the analysis. In the FS1 vs. FS3, FS1 vs. FS5, and FS3 vs. FS5, 4,530, 11,012, and 9,072 differentially expressed genes (DEGs) were identified, respectively. The inter-group screening among the three comparisons yielded 1430 common DEGs. Among these DEGs, 27, 16, and 28 genes were enriched in chlorophyll, carotenoid, and anthocyanin metabolic pathways, respectively. Twelve genes were chosen at random, and the accuracy of the transcriptome data were confirmed using qRT-PCR. The molecular mechanism underlying the pigmentation of jujube fruit was elucidated at the transcriptome level, which would provide a scientific basis for the subsequent functional studies on the color-regulating genes of jujube fruits.

Effects of Jujube Powder on Growth Performance, Blood Biochemical Indices, and Intestinal Microbiota of Broiler

In total, 576 Cobb broilers were randomized into 6 treatment groups, with 8 replicates in each treatment group and 12 broilers in each replicate. Each treatment group was fed six different experimental diets containing 0%, 2%, 4%, 6%, 8%, and 10% jujube powder. The group receiving 0% jujube powder was considered the blank control group. The experimental period was 42 days and was divided into two periods: starter (0-21 days) and finisher (22-42 days). Compared with the control group, the addition of 8% jujube powder significantly improved the ADG of broilers (p < 0.05), and 8% and 10% jujube powder significantly improved the total tract apparent digestibility of organic matter in broilers (p < 0.05). Adding 10% jujube powder significantly improved the apparent metabolic energy of broilers (p < 0.05). Compared with the control group, 4-10% jujube powder significantly increased IgA, IgG, IgM, and sCD4 levels (p < 0.05) and T-AOC and SOD contents, and it reduced the MDA content in the serum of broilers (p < 0.05). In addition, the relative abundance of Firmicutes, Bacteroidetes, Lactobacillus, and Romboutsia significantly increased in the broiler ileum, whereas that of Proteobacteria and Enterobacter decreased significantly (p < 0.05) when 8% jujube powder was added to the diet. The relative abundance of Proteobacteria, Bacteroides, and Faecalibacterium in the cecum increased significantly (p < 0.05), whereas that of Bacteroidetes decreased significantly (p < 0.05).

Study on the spatial specificity of phenolics in fruit of different jujube varieties

Phenol, an important bioactive substance in jujube fruit, is one of the most important indexes of fruit quality. In order to clarify the phenolic substance composition, content and distribution characteristics of different varieties of jujube fruits, this study measured and compared the content of total phenols, total flavonoids and phenolic substance composition in different parts of fruits of six jujube varieties, and combined with the principal component analysis, the results showed that: Fourteen phenolic substances were identified in the fruits of different jujube varieties, and proanthocyanidins, epicatechin, catechin and rutin were the main components, accounting for 58.60%, 16.08%, 13.56% and 5.57% of the total phenolic substances, respectively. The total phenolic and total flavonoid contents of jujube fruits of each variety were between 18.11 and 21.45 mg GAE/g DW and 10.56-20.25 mg RE/g DW, respectively, and the differences in the contents between the varieties were significant, and the contents of 'Junzao' and 'Jinlingyuanzao' were higher than those of other varieties.The phenolic content of different parts of jujube fruits showed spatial distribution differences, manifested as the total phenols, total flavonoids and their fractions of the peel were significantly higher than that of the pulp, while the content of the pulp near the kernel was significantly higher than that of other parts of the pulp, This study provides a theoretical basis for analysing the differences in phenolic substances in jujube fruits.

Study on extraction technology and antioxidant activity of total alkaloids from Hemsleya chinensis based on orthogonal design and BP neural network

In this study, total alkaloids from Hemsleya chinensis were extracted and tested for their antioxidant properties. To optimize extraction methods, a single factor experiment was conducted to determine the total alkaloid concentrations of H. chinensis using the L9 (34) orthogonal design test method and the BP neural network (BPNN), resulting in the optimum extraction conditions for total alkaloids. The optimal conditions for H. chinensis alkaloids extraction with acid water are: HCl concentration is 0.50 %, extraction temperature is 85 °C, material-liquid ratio is 1:64.5, and extraction rate of alkaloids is 0.2785 ± 0.0003 mg/mL. The alkaloid from H. chinensis exhibited antioxidant activity in a quantity-effect relationship with activity. These findings showed that the procedure to be reasonable, the alkaloid extraction efficiency to be high, and the method could be used to extract the alkaloids of H. chinensis, improving the development of natural and healthy medicinal resources for the pharmaceutical and food industries.

Comparison of Bioactive Compounds and Antioxidant Activities in Differentially Pigmented Cerasus humilis Fruits

Chinese dwarf cherry (Cerasus humilis) is a wild fruit tree and medicinal plant endemic to China. Its fruits are rich in various bioactive compounds, such as flavonoids and carotenoids, which contribute greatly to their high antioxidant capacity. In this study, the contents of bioactive substances (chlorophyll, carotenoids, ascorbic acid, anthocyanin, total flavonoids, and total phenols), antioxidant capacities, 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonicacid) (ABTS+) scavenging ability, and ferric-reducing antioxidant power (FRAP)) in differentially pigmented C. humilis fruits of four varieties were determined and compared. The results revealed that anthocyanin, total flavonoids and total phenols were the three main components responsible for the antioxidant activity of C. humilis fruits. 'Jinou No.1' fruits with dark red peel and red flesh had the highest contents of anthocyanin, total flavonoids, and total phenols, as well as the highest antioxidant capacities; 'Nongda No.5' fruits with yellow-green peel and yellow flesh had the highest contents of carotenoids and chlorophyll, while 'Nongda No.6' fruit had the highest ascorbic acid content. To further reveal the molecular mechanism underlying differences in the accumulation of carotenoids and flavonoids among differentially pigmented C. humilis fruits, the expression patterns of structural genes involved in the biosynthesis of the two compounds were investigated. Correlation analysis results revealed that the content of carotenoids in C. humilis fruits was very significantly positively correlated with the expression of the ChCHYB, ChZEP, ChVDE, ChNSY, ChCCD1, ChCCD4, ChNCED1, and ChNCED5 genes (p < 0.01) and significantly negatively correlated with the expression of ChZDS (p < 0.05). The anthocyanin content was very significantly positively correlated with ChCHS, ChFLS, and ChUFGT expression (p < 0.01). The total flavonoid content was very significantly positively correlated with the expression of ChCHS, ChUFGT, and ChC4H (p < 0.01) and significantly positively correlated with ChFLS expression (p < 0.05). This study can provide a basis for understanding the differences in the accumulation of bioactive substances, and is helpful for clarifying the mechanisms underlying the accumulation of various carotenoids and flavonoids among differentially pigmented C. humilis fruits.

Preservation of Phenols, Antioxidant Activity, and Cyclic Adenosine Monophosphate in Jujube (Ziziphus jujuba Mill.) Fruits with Different Drying Methods

Jujube, commonly known as the Chinese date, is a nutritious fruit with medicinal importance. Fresh jujube fruits have a shelf life of about ten days in ambient conditions that can be extended by drying. However, nutrition preservation varies with the drying method and parameters selected. We studied total phenolic content (TPC), proanthocyanidins (PA), vitamin C, cyclic adenosine monophosphate (cAMP), and antioxidant activities in jujube fruits dried with freeze-drying (FD), convective oven drying (OD) at 50 °C, 60 °C, and 75 °C, and sun drying (SD) with FD as a control. The cultivars used for this study were 'Capri' and 'Xiang' from Las Cruces in 2019, and 'Sugarcane', 'Lang', and 'Sherwood' from Las Cruces and Los Lunas, New Mexico, in 2020. Freeze-drying had the highest of all nutrient components tested, the best estimates of mature jujube fruits' nutrient contents. Compared with FD, the majority of PA (96-99%) and vitamin C (90-93%) was lost during SD or OD processes. The retention rates of antioxidant activities: DPPH and FRAP were higher in OD at 50/60 °C than SD. SD retained a higher cAMP level than OD at 50/60 °C in both years. The increase in oven drying temperature from 60 °C to 75 °C significantly decreased TPC, PA, antioxidant activities, and cAMP.

Dietary Dried Jujube Fruit Powder (DJFP) Supplementation Improves Growth Performance, Antioxidant Stability, and Meat Composition in Broilers

Nowadays, broiler production is faced with great challenges due to intensive culture modes, and chickens are more susceptible to oxidative stress. Consequently, synthetic antioxidants have been used to reduce this process, but their use has shown potential health risks. Thus, the use of natural ingredients has been suggested as a strategy to prevent oxidative stress. This study investigated how dietary dried jujube fruit powder (DJFP) supplementation influences the growth performance, antioxidant stability, meat composition, and nutritional quality of Cobb broilers. A total of 360 unsexed broilers (1-day-old) were randomly assigned to treatments that varied in DJFP levels: a basal diet without DJFP (control) and diets supplemented with 50 g/kg DJFP (P1), 100 g/kg DJFP (P2), and 150 g/kg DJFP (P3), with 9 replicates per treatment (90 broilers/treatment or 10 broilers/replicate). The results demonstrated improvement in the growth performance of broilers in terms of body weight (BW), body weight gain (WG), average daily body weight gain (ADG), average daily feed intake (ADFI), and feed conversion ratio (FCR) following dietary DJFP supplementation. In addition, the antioxidant stabilities in the DJFP-treated broilers were improved and inhibited the production of lipid oxidation products compared with the control, with those in the P2 group showing the most marked effect. Moreover, dietary DJFP supplementation significantly increased (p < 0.05) the activity of antioxidant enzymes in broilers. Furthermore, the breast meat of the broilers displayed an increased protein content with a simultaneous reduction in the fat content after DJFP treatment (p < 0.05). Essential amino acid levels were higher in the DJFP-supplemented groups (p < 0.05). The sum of saturated fatty acids was lower, and that of monounsaturated fatty acids (MUFAs) and the polyunsaturated fatty acid/saturated fatty acid ratio (PUFA/SFA) were higher in the DJFP-supplemented groups (p < 0.05). Together, these results indicate that up to 100 g/kg of dietary DJFP supplementation can enhance the growth performance and antioxidant capacity, meat composition, and amino acid and fatty acid composition in broiler breast meat. In conclusion, dietary DJFP supplementation is a healthy alternative to the use of synthetic antioxidants in broiler production, especially in regions rich in jujube resources.

ZjFAS2 is involved in the fruit coloration in Ziziphus jujuba Mill. by regulating anthocyanin accumulation

Fruit color is one of the most important traits of jujube (Ziziphus jujuba Mill.). However, the differences in the pigments of different varieties of Jujube are not well studied. In addition, the genes responsible for fruit color and their underlying molecular mechanisms remain unclear. In this study, two jujube varieties, namely "Fengmiguan" (FMG) and "Tailihong" (TLH), were considered. The metabolites from jujube fruits were investigated using ultra-high-performance liquid chromatography/tandem mass spectrometry. Transcriptome was used to screen anthocyanin regulatory genes. The gene function was confirmed by overexpression and transient expression experiments. The gene expression was analyzed by quantitative reverse transcription polymerase chain reaction analyses and subcellular localization. Yeast-two-hybrid and bimolecular fluorescence complementation were used to screen and identify the interacting protein. These cultivars differed in color owing to their respective anthocyanin accumulation patterns. Three and seven types of anthocyanins were found in FMG and TLH, respectively, which played a key role in the process of fruit coloration. ZjFAS2 positively regulates anthocyanin accumulation. The expression profile of ZjFAS2 exhibited its different expression trends in different tissues and varieties. Subcellular localization experiments showed that ZjFAS2 was localized to the nucleus and membrane. A total of 36 interacting proteins were identified, and the possibility of ZjFAS2 interacting with ZjSHV3 to regulate jujube fruit coloration was studied. Herein, we investigated the role of anthocyanins in the different coloring patterns of the jujube fruits and provided a foundation for elucidating the molecular mechanism underlying jujube fruit coloration.

The Grade of Dried Jujube (Ziziphus jujuba Mill. cv. Junzao) Affects Its Quality Attributes, Antioxidant Activity, and Volatile Aroma Components

Jujube (Ziziphus jujuba Mill. cv. Junzao) has attracted a large number of consumers because it is rich in nutrients, such as carbohydrates, organic acids, and amino acids. Dried jujube is more conducive to storage and transportation, and has a more intense flavor. Consumers are affected by subjective factors, and the most important factor is the appearance of the fruit, including size and color. In this study, fully matured jujubes were dried and divided into five grades according to their transverse diameter and jujube number per kilogram. In addition, the quality attributes, antioxidant activities, mineral elements, and volatile aroma components of dried jujube were further analyzed. As the dried jujube grade increased, the total flavonoid content increased, which was positively correlated with the antioxidant activity. The results showed that small dried jujube had a higher total acidity and lower sugar-acid ratio than large and medium dried jujube, thus, large and medium dried jujube had a better flavor than small dried jujube. However, the antioxidant activity and mineral elements of medium and small dried jujube were superior to large dried jujube. From the edible value analysis of dried jujube, medium and small dried jujube were better than large dried jujube. Potassium is the highest among the measured mineral elements, with contents ranging from 10,223.80 mg/kg to 16,620.82 mg/kg, followed by Ca and Mg. Twenty-nine volatile aroma components of dried jujube were identified by GC-MS analysis. The main volatile aroma components were acids including n-decanoic acid, benzoic acid, and dodecanoic acid. The fruit size affected the quality attributes, antioxidant activity, mineral elements, and volatile aroma components of dried jujube. This study provided a piece of reference information for further high-quality production of dried jujube fruit.

Effects of cold plasma, high hydrostatic pressure, ultrasound, and high-pressure carbon dioxide pretreatments on the quality characteristics of vacuum freeze-dried jujube slices

Pretreatment combined with vacuum freeze-drying is an effective technique to extend the storage period of jujube fruits and reduce energy consumption and cost; however, the effects of pretreatment on the quality characteristics of jujube during vacuum freeze-drying remain unknown. In this study, the effects of cold plasma (CP), high hydrostatic pressure (HHP), ultrasound (US), high-pressure carbon dioxide (HPCD), and conventional blanching (BC) as pretreatments on the performance of vacuum freeze-dried jujube slices were investigated. The results indicated that the application of different pretreatments decreased the water activity and increased the rehydration capacity, owing to the pretreatment etching larger and more porous holes in the microstructure. Freeze-dried jujube slices pretreated with HPCD retained most of their quality characteristics (color, hardness, and volatile compounds), followed by the HHP- and US-pretreated samples, whereas samples pretreated with BC showed the greatest deterioration in quality characteristics, and hence, BC is not recommended as a pretreatment for freeze-dried jujube slices. Sensory evaluation based on hedonic analysis showed that jujube slices pretreated with HPCD and US were close to the control sample and scored highest. Compared to other pretreated samples and the control, freeze-dried jujube slices pretreated with HPCD showed the least degradation (4.93%) of cyclic adenosine monophosphate (cAMP), the highest contents of total phenol, total flavonoid, and l-ascorbic acid, and the highest antioxidant capacity. Partial least squares-discriminant analysis (PLS-DA) was performed to screen all the quality characteristic data of different pretreated samples, and 12 volatile compounds, including ethyl hexanoate and (E)-2-hexenal, along with color, l-ascorbic acid content, and cAMP content were found suitable to be used as discriminators for pretreated freeze-dried jujube slices. Therefore, non-thermal pretreatments, including HPCD, US, and HHP pretreatments, are promising techniques for the vacuum freeze-drying of jujube products.

Active compound analysis of Ziziphus jujuba cv. Jinsixiaozao in different developmental stages using metabolomic and transcriptomic approaches

Jujube (Ziziphus jujuba Mill.) is a popular fruit with health benefits ascribed to its various metabolites. These metabolites determine the flavors and bioactivities of the fruit, as well as their desirability. However, the dynamics of the metabolite composition and the underlying gene expression that modulate the overall flavor and accumulation of active ingredients during fruit development remain largely unknown. Therefore, we conducted an integrated metabolomic and transcriptomic investigation covering various developmental stages in the jujube cultivar Z. jujuba cv. Jinsixiaozao, which is famous for its nutritional and bioactive properties. A total of 407 metabolites were detected by non-targeted metabolomics. Metabolite accumulation during different jujube developmental stages was examined. Most nucleotides and amino acids and their derivatives accumulated during development, with cAMP increasing notably during ripening. Triterpenes gradually accumulated and were maintained at high concentrations during ripening. Many flavonoids were maintained at relatively high levels in early development, but then rapidly decreased later. Transcriptomic and metabolomic analyses revealed that chalcone synthase (CHS), chalcone isomerase (CHI), flavonol synthase (FLS), and dihydroflavonol 4-reductase (DFR) were mainly responsible for regulating the accumulation of flavonoids. Therefore, the extensive downregulation of these genes was probably responsible for the decreases in flavonoid content during fruit ripening. This study provide an overview of changes of active components in 'Jinsixiaozao' during development and ripening. These findings enhance our understanding of flavor formation and will facilitate jujube breeding for improving both nutrition and function.

Extraction of red pigment from Chinese jujube peel and the antioxidant activity of the pigment extracts

Chinese jujube is a delicious fruit with high antioxidant nutrients. The fruit peel, however, is always discarded due to its indigestibility. In the current study, the jujube peels were collected for red pigment extraction. Six extraction-related parameters (ethanol concentration, solid-liquid ratio, material granularity, enzyme concentration, enzymolysis time, and pH) were optimized for jujube peel pigment extraction using Plackett–Burman and Box–Behnken designs. When the fruit peels were treated with 1.18% cellulase and 73% ethanol at pH 3.15, optimization enhanced the pigment extraction efficiency by 29.7% compared with the control. Ultra-high performance liquid chromatography (UHPLC) assay revealed that delphinidin 3-O-galactoside and cyanidin 3-O-rutinoside chloride were the major components of the jujube pigment extracts. Additionally, the red pigment extracts exhibited high free radical scavenging capacity and strong Fe3+ reducing power. Finally, it also provides us a simple new method for efficient extraction of natural antioxidants from discarded jujube peels.

Combining Transcriptomics and Polyphenol Profiling to Provide Insights into Phenolics Transformation of the Fermented Chinese Jujube

As an important medicine homologous food, Chinese jujube is rich in nutrition and medicinal value. To enhance the bioactive compounds level of Chinese jujube products, three kinds of fungi strains (Rhizopus oryzae, Aspergillus niger and Monascus purpureus) were firstly selected to evaluate their effects on total soluble phenolic compounds (TSPC) and total soluble flavonoids compounds (TSFC) contents during liquid state fermentation of Chinese jujube. As the best strain, the highest contents of TSPC and TSFC could increase by 102.1% (26.02 mg GAE/g DW) and 722.8% (18.76 mg RE/g DW) under M. purpureus fermentation when compared to the unfermented sample, respectively. Qualitative and quantitative analysis of individual polyphenol compounds indicated that proto-catechuic acid, p-hydroxybenzoic acid and chlorogenic acid showed the highest level in the fer-mented Chinese jujube at the 7th day, which was enhanced by 16.72-, 14.05- and 6.03-fold when compared to the control, respectively. Combining with RNA sequencing, function annotation of CAZymes database and polyphenol profiling, three potential transformation pathways of poly-phenol compounds were proposed in the fermented Chinese jujube by M. purpureus, such as the conversion of insoluble bound phenolic acids, rutin and anthocyanin degradation. These findings would be beneficial for better understanding of the biotransformation mechanism of polyphenol compounds in fungi fermentation.

The Inclusion of Jujube By-Products in Animal Feed: A Review

Given the increasing demands for the quality and safety of animal-derived foods and the strict regulations on the use of antibiotics in animal feed, the use of functional feed additives has attracted increasing research and development. Jujube fruit is an energy-rich food with antioxidant, antibacterial, and antidiarrheal properties. With the expanding areas of cultivation to jujube trees and the intensive processing of jujube in Asia, especially in China, a large number of jujube by-products are produced. These by-products are used widely in animal feed for pigs, chicken, cattle, goats, and fish, as they improve growth performance, promote digestive tract health, and enhance the quality of animal products. This article reviews the nutritional components and benefits of jujube by-products and their potential incorporation in animal feed. The aim of this review is to introduce jujube by-products as a novel supplement or partial dietary replacement in the animal feed industry.

Physicochemical and antioxidant activity of fruit harvested from eight jujube (Ziziphus jujuba Mill.) cultivars at different development stages

Jujube is a crop highly resistant to drought and salinity, making it one of the main fruit trees in Xinjiang. The present study evaluated the changes in the physicochemical and antioxidant activities of jujube fruit of eight different cultivars from Xinjiang, China. The developmental stages were selected according to the days after full bloom and fruit peel colour during ripening; these stages included young (S1), fruit core-hardening (S2), green ripening (S3), half-red maturity (S4) and complete red. In present study, different cultivars of jujube fruit showed similar chemical profiles, but their amounts showed great variation. HZ had the highest content of sugars, and JY had the highest content of cAMP and cGMP, while relatively higher levels of ascorbic acid, catechin, epicatechin, rutin, proanthocyanidin and antioxidant activity were found in ‘FS’ than in other cultivars, indicating that ‘FS’ could be used as a potential natural antioxidant. Regarding the development stages of jujube fruit, the moisture, ascorbic acid, total polyphenol, catechin, epicatechin, proanthocyanidin and rutin contents decreased during the development of all jujube cultivars, while the fructose, glucose, sucrose, cAMP, and cGMP contents greatly increased. The antioxidant activity determined by DPPH and ABTS radical scavenging decreased as the fruits matured. Therefore, the results suggest that green jujube (S1) could be used for natural antioxidants (catechin, epicatechin, proanthocyanidin) and that the advanced ripening stage(S5) is the proper picking period for fresh fruit and commercial processing.

Beneficial Effects of Jujube Juice Fermented by Lactobacillus plantarum NXU19009 on Acute Alcoholic Liver Injury in Mice

Red jujube (Ziziphus jujuba Mill.) is an important fruit that has the concomitant function of both medicine and food. It has been proven to be rich in various bioactive components. In the present study, jujube juice was fermented by Lactobacillus plantarum NXU19009 to enhance the flavor and nutritional benefits. Its potential for the prevention and treatment of acute alcohol induced-liver injury in mice was examined in this study. The results showed that the administration of the fermented jujube juice along with alcohol significantly decreased (p < 0.01) the liver indices, as well as the levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), alcohol dehydrogenase (ADH), total triglyceride (TG), total cholesterol (TC), and liver malondialdehyde (MDA) in the serum. In contrast, the levels of liver superoxide dismutase (SOD) and glutathione (GSH) in mice administered with fermented jujube juice were found to increase significantly (p < 0.01). Furthermore, the administration of fermented jujube juice in mice was found to alter their intestinal microbiota and an improvement was observed based on the results obtained in the histopathology examination. Therefore, Jujube juice fermented by Lactobacillus plantarum NXU19009 protects against liver injury and may prove to be an effective supplement to attenuate acute alcoholic liver injury.

Propyl Gallate Treatment Improves the Postharvest Quality of Winter Jujube (Zizyphus jujuba Mill. cv. Dongzao) by Regulating Antioxidant Metabolism and Maintaining the Structure of Peel

The quality and color of winter jujube fruits are easy to change after harvest. We studied the regulation mechanism of propyl gallate (PG) on post-harvest physiological quality of winter jujube, from the perspective of antioxidant metabolism and peel structure. In our research, winter jujube fruits were treated with 0.001 mol L⁻¹ PG solution for 20 min. Our results showed that PG delayed the development of peel color, and improved the firmness, total soluble solids (TSS), and titratable acid (TA) of winter jujube. Meanwhile, the PG treatment had higher content of total phenols, total flavonoids, ascorbic acid (AsA), and reduced glutathione (GSH), and kept the enzyme activity including superoxide dismutase (SOD), catalase (CAT), ascorbate peroxidase (APX), and peroxidase (POD) at a higher level. PG treatment reduced membrane oxidative damage and maintained the integrity of pericarp structure by reducing electrolyte leakage (EL), lipoxygenase activity (LOX), hydrogen peroxide (H₂O₂), and malondialdehyde (MDA) content in the peel. Accordingly, PG improved the postharvest quality of jujube fruits by regulating antioxidant metabolism and maintaining the structure of peel. The appropriate concentration of PG has good application potential in the storage and preservation of fresh fruits such as winter jujube.

Composition and content of phenolic acids and flavonoids among the different varieties, development stages, and tissues of Chinese Jujube (Ziziphus jujuba Mill.)

The composition and content of phenolic acids and flavonoids among the different varieties, development stages, and tissues of Chinese jujube (Ziziphus jujuba Mill.) were systematically examined using ultra-high-performance liquid chromatography to provide a reference for the evaluation and selection of high-value resources. Five key results were identified: (1) Overall, 13 different phenolic acids and flavonoids were detected from among the 20 excellent jujube varieties tested, of which 12 were from the fruits, 11 from the leaves, and 10 from the stems. Seven phenolic acids and flavonoids, including (+)-catechin, rutin, quercetin, luteolin, spinosin, gallic acid, and chlorogenic acid, were detected in all tissues. (2) The total and individual phenolic acids and flavonoids contents significantly decreased during fruit development in Ziziphus jujuba cv.Hupingzao. (3) The total phenolic acids and flavonoids content was the highest in the leaves of Ziziphus jujuba cv.Hupingzao, followed by the stems and fruits with significant differences among the content of these tissues. The main composition of the tissues also differed, with quercetin and rutin present in the leaves; (+)-catechin and rutin in the stems; and (+)-catechin, epicatechin, and rutin in the fruits. (4) The total content of phenolic acid and flavonoid ranged from 359.38 to 1041.33 μg/g FW across all examined varieties, with Ziziphus jujuba cv.Jishanbanzao having the highest content, and (+)-catechin as the main composition in all 20 varieties, followed by epicatechin, rutin, and quercetin. (5) Principal component analysis showed that (+)-catechin, epicatechin, gallic acid, and rutin contributed to the first two principal components for each variety. Together, these findings will assist with varietal selection when developing phenolic acids and f lavonoids functional products.

Quantitative Assessment of Abiotic Stress on the Main Functional Phytochemicals and Antioxidant Capacity of Wheatgrass at Different Seedling Age

The wheat seedlings of 6 days old were daily subjected to ultraviolet irradiation (irradiating for 5, 10, 20, 40, and 60 min/day, respectively), Polyethylene glycol 6000 (5, 10, 15, 20, 25% in 1/2 Hoagland solution, respectively), and salinity solution (10, 25, 50, 100, 200 mM in 1/2 Hoagland solution, respectively), while the control group (CK) was supplied only with the Hoagland solution. The wheatgrass was harvested regularly seven times and the total soluble polysaccharides, ascorbic acid, chlorophyll, total polyphenol, total triterpene, total flavonoid, and proanthocyanins content were tested. The antioxidant capacity was evaluated through 2,2'-azino-bis (3-ethylbenzthia-zoline-6-sulfonic acid) (ABTS), 2,2-diphenyl-1-picrylhydrazyl (DPPH) scavenging ability, and ferric ion reducing power. Technique for order preference by similarity to ideal solution (TOPSIS) mathematical model was adopted to comprehensively assess the functional phytochemicals of the different treatments. The results showed that the accumulation patterns of phytochemicals under abiotic stress were complex and not always upregulated or downregulated. The antioxidant activity and functional phytochemicals content of wheatgrass were significantly affected by both the stress treatments and seedling age, while the latter affected the chemicals more efficiently. The top five highest functional phytochemicals were observed in the 200 mM NaCl treated group on the 21st and 27th day, 25% PEG treated group on the 24th day, 200 mM NaCl treated group on the 24th day, and the group of 40 min/day ultraviolet exposure on 27th day.

Research advances in bioactive components and health benefits of jujube (Ziziphus jujuba Mill.) fruit

Jujube (Ziziphus jujuba Mill.), a highly nutritious and functional fruit, is reported to have various health benefits and has been extensively planted worldwide, especially in China. Many studies have shown that bioactive components derived from jujube fruit have significant nutritional and potential biological effects. In this paper, the latest progress in research on major bioactive compounds obtained from jujube is reviewed, and the potential biological functions of jujube fruit resources are discussed. As a dietary supplement, jujube fruit is well recognized as a healthy food which contains a variety of bioactive substances, such as polysaccharides, polyphenols, amino acids, nucleotides, fatty acids, dietary fiber, alkaloids, and other nutrients. These nutrients and non-nutritive phytochemicals obtained from jujube fruit have physiological functions including anticancer, antioxidant, anti-inflammatory, anti-hyperlipidemic, anti-hyperglycemic, immunoregulatory, neuroprotective, sedative, and antiviral functions. Of note is that new constituents, including alkaloids, dietary fiber, and other bioactive substances, as well as the antiviral, hypoglycemic, lipid-lowering, and neuroprotective effects of jujube fruit, are systematically reviewed here for the first time. Meanwhile, problems affecting the exploitation of jujube fruit resources are discussed and further research directions proposed. Therefore, this review provides a useful bibliography for the future development of jujube-based products and the utilization of jujube nutritional components in functional foods.

Physiological and metabolic analysis of winter jujube after postharvest treatment with calcium chloride and a composite film

BACKGROUND

Ziziphus jujuba Miller cv. Dongzao is extremely susceptible to reddening, browning, nutritional loss, and perishability after harvest. In this study, we evaluated the mechanisms of calcium chloride and chitosan/nano-silica composite film treatments on the quality, especially in reddening, by physiological and metabolomic assays.

RESULTS

The treatment delayed the decline of phenylalanine ammonia-lyase (PAL), chalcone synthase (CHS), and chalcone isomerase (CHI) activities. Meanwhile, the treated groups retarded the increases in anthocyanin and quercetin contents by inhibiting the gene expressions of flavonol synthase (ZjFLS), dihydroflavonol 4-reductase (ZjDFR), and anthocyanidin synthase (ZjANS), while promoting leucoanthocyanidin reductase (ZjLAR) expression, which leads to retardation of fruit reddening. Anthocyanins were found to be responsible for post-harvest winter jujube reddening through principal component analysis. Results from the technique for order preference by similarity to an ideal solution indicated that the treated group delayed the decline of the quality of 'Dongzao' and extended its shelf life.

CONCLUSION

The treatment induced the heightening of flavonoids metabolism. They enhanced the nutritional value and the ability to resist stress by delaying the decline of PAL, CHS, and CHI activities. Meanwhile, the treated groups retarded the increase in anthocyanin and quercetin contents by inhibiting the gene expressions of ZjFLS, ZjDFR, and ZjANS and promoting ZjLAR expression, which leads to retardation of fruit reddening. Anthocyanins are responsible for post-harvest winter jujube reddening. Coating treatment effectively delayed the decline of winter jujube quality. © 2020 Society of Chemical Industry.

Comprehensive Evaluation of the Effect of Ultraviolet Stress on Functional Phytochemicals of Hulless Barley (Qingke) Grass in Different Growth Times at Vegetative Stage

The present study was executed to analyze the functional phytochemicals of hulless barley grass grown under different intensities of ultraviolet stress. The wheat seedlings were imposed to 0.5, 1.0, 1.5, 2.0, and 2.5 h ultraviolet radiation and harvested in different times at vegetative stage. Specifically, the contents of total polyphenols, total flavonoids, total triterpenes, total polysaccharides, proanthocyanidins, and chlorophyll were determined and antioxidants capacity was evaluated by OH^• and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) scavenging ability. A mathematical model (Technique for Order Preference by Similarity to Ideal Solution, TOPSIS) was also employed for the comprehensive evaluation of functional components of hulless barley grass at different growth stages. The results showed that the UV stress could efficiently improve/preserve the contents of total polyphenols, total flavonoids, total triterpenes, total polysaccharides, proanthocyanidins, chlorophyll a, chlorophyll b, and total chlorophyll, as well as the OH^• and ABTS scavenging capacity. TOPSIS evaluation revealed that the highest phytochemical contents were yield on the 15th day under 1.0 h ultraviolet treatment.