Anthocyanin biosynthesis in goji berry is inactivated by deletion in a bHLH transcription factor LrLAN1b promoter.

Black goji berry (Lycium ruthenicum Murray) contains a rich source of health-promoting anthocyanins which are used in herbal medicine and nutraceutical foods in China. A natural variant producing white berries allowed us to identify two key genes involved in the regulation of anthocyanin biosynthesis in goji berries: one encoding a MYB transcription factor (LrAN2-like) and one encoding a basic helix-loop-helix (bHLH) transcription factor (LrAN1b). We previously found that LrAN1b expression was lost in the white berry variant, but the molecular basis for this phenotype was unknown. Here, we identified the molecular mechanism for loss of anthocyanins in white goji berries. In white goji, the LrAN1b promoter region has a 229 bp deletion that removes three MYB-binding elements and one bHLH-binding element, which are key to its expression. Complementation of the white goji berry LrAN1b allele with the LrAN1b promoter restored pigmentation. Virus-induced gene silencing of LrAN1b in black goji berry reduced fruit anthocyanin biosynthesis. Molecular analyses showed that LrAN2-like and another bHLH transcription factor LrJAF13 can activate LrAN1b by binding directly to the MYB-recognizing element and bHLH-recognizing element of its promoter-deletion region. LrAN1b expression is enhanced by the interaction of LrAN2-like with LrJAF13 and the WD40 protein LrAN11. LrAN2-like and LrAN11 interact with either LrJAF13 or LrAN1b to form two MYB-bHLH-WD40 complexes, which hierarchically regulate anthocyanin biosynthesis in black goji berry. This study on a natural variant builds a comprehensive anthocyanin regulatory network that may be manipulated to tailor goji berry traits.

Integrated metabolome and transcriptome analysis of differences in quality of ripe Lycium barbarum L. fruits harvested at different periods.

BACKGROUND: Wolfberry is well-known for its high nutritional value and medicinal benefits. Due to the continuous ripening nature of Goji berries and the fact that they can be commercially harvested within a few weeks, their phytochemical composition may change during the harvesting process at different periods. RESULT: The involved molecular mechanisms of difference in fruit quality of ripe Lycium barbarum L. harvested at four different periods were investigated by transcriptomic and metabolomics analyses for the first time. According to the results we obtained, it was found that the appearance quality of L. barbarum fruits picked at the beginning of the harvesting season was superior, while the accumulation of sugar substances in L. barbarum fruits picked at the end of the harvesting season was better. At the same time the vitamin C and carotenoids content of wolfberry fruits picked during the summer harvesting season were richer. Ascorbic acid, succinic acid, glutamic acid, and phenolic acids have significant changes in transcription and metabolism levels. Through the network metabolic map, we found that ascorbic acid, glutamic acid, glutamine and related enzyme genes were differentially accumulated and expressed in wolfberry fruits at different harvesting periods. Nevertheless, these metabolites played important roles in the ascorbate-glutathione recycling system. Ascorbic acid, phenolic substances and the ascorbate-glutathione recycling system have antioxidant effects, which makes the L. barbarum fruits harvested in the summer more in line with market demand and health care concepts. CONCLUSION: This study laid the foundation for understanding the molecular regulatory mechanisms of quality differences of ripe wolfberry fruits harvested at different periods, and provides a theoretical basis for enhancing the quality of L. barbarum fruits.

Metabolite-based genome-wide association studies enable the dissection of the genetic bases of flavonoids, betaine and spermidine in wolfberry (Lycium).

Wolfberry is a plant with medicinal and food values. However, its bioactive ingredients and the corresponding genetic bases have not been determined. Here, we de novo generated a chromosome-level genome assembly for wolfberry, yielding a genome sequence of ~1.77 Gb with contig N50 of 50.55 Mb and 39 224 predicted gene models. A variation map, using 307 re-sequenced accessions, was called based on this genome assembly. Furthermore, the fruit metabolome of these accessions was profiled using 563 annotated metabolites, which separated Lycium barbarum L. and non-L. barbarum L. The flavonoids, coumarins, alkaloids and nicotinic acid contents were higher in the former than in the latter. A metabolite-based genome-wide association study mapped 156 164 significant single nucleotide polymorphisms corresponding to 340 metabolites. This included 19 219 unique lead single nucleotide polymorphisms in 1517 significant association loci, of which three metabolites, flavonoids, betaine and spermidine, were highlighted. Two candidate genes, LbUGT (evm.TU.chr07.2692) and LbCHS (evm.TU.chr07.2738), with non-synonymous mutations, were associated with the flavonoids content. LbCHS is a structural gene that interacts with a nearby MYB transcription factor (evm.TU.chr07.2726) both in L. barbarum and L. ruthenicum. Thus, these three genes might be involved in the biosynthesis/metabolism of flavonoids. LbSSADH (evm.TU.chr09.627) was identified as possibly participating in betaine biosynthesis/metabolism. Four lycibarbarspermidines (E-G and O) were identified, and only the lycibarbarspermidines O content was higher in L. barbarum varieties than in non-L. barbarum varieties. The evm.TU.chr07.2680 gene associated with lycibarbarspermidines O was annotated as an acetyl-CoA-benzylalcohol acetyltransferase, suggesting that it is a candidate gene for spermidine biosynthesis. These results provide novel insights into the specific metabolite profile of non-L. barbarum L. and the genetic bases of flavonoids, betaine and spermidine biosynthesis/metabolism.

Goji Berry Juice Prevents Tumor Necrosis Factor Alpha-Induced Xerostomia in Human Salivary Gland Cells.

Sjögren's syndrome (SS) is an autoimmune disorder characterized by oral dryness that is primarily attributed to tumor necrosis factor alpha (TNF-α)-mediated reduction in saliva production. In traditional Chinese medicine, goji berries are recognized for their hydrating effect and are considered suitable to address oral dryness associated with Yin deficiency. In the present study, we used goji berry juice (GBJ) to investigate the potential preventive effect of goji berries on oral dryness caused by SS. Pretreatment of human salivary gland cells with GBJ effectively prevented the decrease in aquaporin-5 (AQP-5) mRNA and protein levels induced by TNF-α. GBJ also inhibited histone H4 deacetylation and suppressed the generation of intracellular reactive oxygen species (ROS). Furthermore, GBJ pretreatment reserved mitochondrial membrane potential and suppressed the upregulation of Bax and caspase-3, indicating that GBJ exerted an antiapoptotic effect. These findings suggest that GBJ provides protection against TNF-α in human salivary gland cells and prevents the reduction of AQP-5 expression on the cell membrane. Altogether, these results highlight the potential role of GBJ in preventing oral dryness caused by SS.

LbCOPT1 is a copper transporter induced in Lycium barbarum mycorrhizal roots, which allows tobacco with improved growth and nutrient uptake.

KEY MESSAGE: Overexpressing the copper transporter LbCOPT1 leads to a notable increase in the abundance of mycorrhizal arbuscules that suggests the potential application of LbCOPT1 in breeding programs aimed at enhancing symbiotic nutrient uptake in Lycium barbarum L.

Integration of Transcriptome and Metabolome Reveals Wax Serves a Key Role in Preventing Leaf Water Loss in Goji (Lycium barbarum).

Drought stress is one of the main abiotic stresses that limit plant growth and affect fruit quality and yield. Plants primarily lose water through leaf transpiration, and wax effectively reduces the rate of water loss from the leaves. However, the relationship between water loss and the wax formation mechanism in goji (Lycium barbarum) leaves remains unclear. 'Ningqi I' goji and 'Huangguo' goji are two common varieties. In this study, 'Ningqi I' goji and 'Huangguo' goji were used as samples of leaf material to detect the differences in the water loss rate, chlorophyll leaching rate, wax phenotype, wax content, and components of the two materials. The differences in wax-synthesis-related pathways were analyzed using the transcriptome and metabolome methods, and the correlation among the wax components, wax synthesis genes, and transcription factors was analyzed. The results show that the leaf permeability of 'Ningqi I' goji was significantly lower than that of 'Huangguo' goji. The total wax content of the 'Ningqi I' goji leaves was 2.32 times that of the 'Huangguo' goji leaves, and the epidermal wax membrane was dense. The main components of the wax of 'Ningqi I' goji were alkanes, alcohols, esters, and fatty acids, the amounts of which were 191.65%, 153.01%, 6.09%, and 9.56% higher than those of 'Huangguo' goji, respectively. In the transcriptome analysis, twenty-two differentially expressed genes (DEGs) and six transcription factors (TFs) were screened for wax synthesis; during the metabolomics analysis, 11 differential metabolites were screened, which were dominated by lipids, some of which, like D-Glucaro-1, 4-Lactone, phosphatidic acid (PA), and phosphatidylcholine (PE), serve as prerequisites for wax synthesis, and were significantly positively correlated with wax components such as alkanes by the correlation analysis. A combined omics analysis showed that DEGs such as LbaWSD1, LbaKCS1, and LbaFAR2, and transcription factors such as LbaMYB306, LbaMYB60, and LbaMYBS3 were strongly correlated with wax components such as alkanes and alcohols. The high expression of DEGs and transcription factors is an important reason for the high wax content in the leaf epidermis of 'Ningqi I' goji plants. Therefore, by regulating the expression of wax-synthesis-related genes, the accumulation of leaf epidermal wax can be promoted, and the epidermal permeability of goji leaves can be weakened, thereby reducing the water loss rate of goji leaves. The research results can lay a foundation for cultivating drought-tolerant goji varieties.

Lycium barbarum glycopeptide alleviates neuroinflammation in spinal cord injury via modulating docosahexaenoic acid to inhibiting MAPKs/NF-kB and pyroptosis pathways.

BACKGROUND: Lycium barbarum polysaccharide (LBP) is an active ingredient extracted from Lycium barbarum that inhibits neuroinflammation, and Lycium barbarum glycopeptide (LbGp) is a glycoprotein with immunological activity that was purified and isolated from LBP. Previous studies have shown that LbGp can regulate the immune microenvironment, but its specific mechanism of action remains unclear. AIMS: In this study, we aimed to explore the mechanism of action of LbGp in the treatment of spinal cord injury through metabolomics and molecular experiments. METHODS: SD male rats were randomly assigned to three experimental groups, and after establishing the spinal cord hemisection model, LbGp was administered orally. Spinal cord tissue was sampled on the seventh day after surgery for molecular and metabolomic experiments. In vitro, LbGp was administered to mimic the inflammatory microenvironment by activating microglia, and its mechanism of action in suppressing neuroinflammation was further elaborated using metabolomics and molecular biology techniques such as western blotting and q-PCR. RESULTS: In vivo and in vitro experiments found that LbGp can improve the inflammatory microenvironment by inhibiting the NF-kB and pyroptosis pathways. Furthermore, LbGp induced the secretion of docosahexaenoic acid (DHA) by microglia, and DHA inhibited neuroinflammation through the MAPK/NF-κB and pyroptosis pathways. CONCLUSIONS: In summary, we hypothesize that LbGp improves the inflammatory microenvironment by regulating the secretion of DHA by microglia and thereby inhibiting the MAPK/NF-κB and pyroptosis pathways and promoting nerve repair and motor function recovery. This study provides a new direction for the treatment of spinal cord injury and elucidates the potential mechanism of action of LbGp.

Transcriptomics integrated with metabolomics reveals the effect of Lycium barbarum polysaccharide on apoptosis in Nile tilapia (Oreochromis niloticus).

Lycium barbarum polysaccharide (LBP) is one of the main active ingredients in the fruit of L. barbarum L. It has been used as herbal medicine for thousands of years in China. In this study, Nile tilapia (Oreochromis niloticus) was taken as the research object. After feeding tilapia with 5 different doses of LBP (0 mg/kg, 500 mg/kg, 1000 mg/kg, 1500 mg/kg, 2000 mg/kg) for 55 d, it was found that LBP could promote the growth of tilapia, and this effect was the strongest at Group 1500 mg/kg. Apoptosis analysis in the liver and spleen showed that dietary supplementation with 1000 mg/kg LBP had the best protective effect on the spleen and liver in tilapia. Combined transcriptomics and metabolomics of the spleen in tilapia at Group 0 mg/kg and 1000 mg/kg showed that the differentially expressed genes (DEGs) such as NT5C2L1, pmm1, FasL and the differentially metabolites such as xanthine, dGMP, guanine and glutamate were mainly concentrated in signaling pathways such as Purine metabolism and FoxO signaling pathway. In conclusion, LBP regulates the metabolic waste levels of tilapia mainly through Purine metabolism and the FoxO signaling pathway, thereby inhibiting cell apoptosis, improving the utilization of nutrients, and promoting the growth of tilapia. This study not only provides a theoretical basis for the application of LBP in aquatic animals but also provides useful information for the healthy development of the aquaculture.

The Ethanolic Extract of Lycium ruthenicum Ameliorates Age-Related Physiological Damage in Mice.

Aging and age-related diseases are important study topics due to their associations with progressive physiological damage to genes, cells, tissues, and the entire organism, which ultimately affects the functional efficiency of organs. Lycium ruthenicum Murr. is a functional food that is known for its high contents of anthocyanins and spermidines, both of which have been demonstrated to have positive effects on anti-aging activity and anti-oxidation. In this study, we used HPLC-MS to analyze the constituents of L. ruthenicum Murr. Extract (LRM) and investigated their potential mechanism for exerting antioxidative effects in D-galactose (D-Gal) aging model mice. LRM (25 mg/kg, 50 mg/kg, and 100 mg/kg) improved cognitive function in D-Gal-treated mice, as shown by reduced escape latencies and increased platform crossings in behavioral tests. We measured the contents of lipid peroxidation (LPO) and malondialdehyde (MDA) and the enzyme activities of the antioxidant enzymes superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) in mice serum and brain after 6 weeks of D-Gal treatment. LRM decreased the contents of LPO and MDA and increased the enzyme activities of SOD and GSH-Px, indicating the protection effect of LRM against D-Gal-induced oxidative stress. Additionally, LRM can inhibit oxidative stress in cells by reducing intracellular ROS levels and restoring mitochondrial membrane potential, thereby inhibiting paraquat (PQ)-induced cellular senescence and delaying cell aging. Therefore, LRM has the potential to be a healthcare product for the treatment of age-related diseases.

Neuroprotective Effects of Lycium Barbarum Fruit Extract on Pink1B9Drosophila Melanogaster Genetic Model of Parkinson's Disease.

Lycium barbarum (LB) is a famous traditional Chinese medicinal plant as well as food supplement possessing various pharmacological functions such as anti-aging and antioxidant effects. The Parkinson's disease (PD)-related kinase Pink1 plays vital role in maintaining the neuron cell homeostasis, having been recognized as a potential target for the development of anti-PD drugs. In this work, the neuroprotective effects of methanol extract of LB fruit (LBFE) were investigated using a Drosophila PD model (PINK1B9) and a human neuroblastoma SH-SY5Y cell line. We found that when LBFE was supplied to the PINK1B9 flies at 6, 12, and 18 days of age, it raised the ATP and dopamine levels at all ages, extended life span, improved motor behavior, and rescued olfactory deficits of the PINK1B9 flies. In addition, histopathological examinations indicated that muscle atrophy in thoraces of the mutant flies was significantly repaired. Finally, LBFE was able to rescue the SH-SY5Y cells against MPP+-induced neurotoxicity. This work reports for the first time the anti-PD potential of L. barbarum fruit extract in PINK1 mutant fruit flies, presenting a new viewpoint for studing the mechanism of action of LBFE.

Mechanism of 2,4-Dichlorophenoxyacetic acid-induced damage to rat testis via Fas/FasL pathway and the protective effect of Lycium barbarum polysaccharides.

The herbicide 2,4-Dichlorophenoxyacetic acid (2,4-D) is widely used to control broadleaved weeds and has been associated with male infertility. We studied the molecular mechanisms of 2,4-D induced male reproductive system damage and the protective effects of Lycium barbarum polysaccharides (LBP) using Sprague Dawley rats and TM4 cells. Treatment with 2,4-D caused architectural and functional changes in the testis, including collapsed and atrophied seminiferous tubules with reduced number of spermatozoa, scarce sperm in the epididymal duct, low levels of serum testosterone, decreased superoxide dismutase and glutathione peroxidase activity, high malondialdehyde content, and increased apoptosis in the testis and epididymis. The expression of Fas, FasL, FADD, Pro-caspase-8, Cleaved-Caspase-8, Pro-Caspase-3, and Cleaved-Caspase-3 were significantly increased in the testicular tissue of 2,4-D-treated rats. The proliferative activity of TM4 cells decreased with an increase in dose and time of 2,4-D exposure, along with enhanced Fas/Fas ligand expression and a decreased concentration of inhibin B in TM4 cell culture medium. Depletion of Fas by specific shRNA transfection reversed the effects of 2,4-D in TM4 cells, further confirming the involvement of death receptor pathway in 2,4-D-mediated apoptosis of sertoli cells. Treatment with LBP also reversed the effects of 2,4-D in testicular cells, resulting in improved cell architecture along with enhanced proliferative capacity. Moreover, in response to LBP treatment of Sertoli cells, the content of inhibin B increased, the level of reactive oxygen species and malondialdehyde decreased, the activities of superoxide dismutase and glutathione peroxidase increased, and the rate of apoptosis as well as the expression of Fas/Fas ligand signaling pathway proteins decreased.

Genome-Wide Identification and Analysis of the BBX Gene Family and Its Role in Carotenoid Biosynthesis in Wolfberry (Lycium barbarum L.).

The B-box proteins (BBXs) are a family of zinc-finger transcription factors with one/two B-Box domain(s) and play important roles in plant growth and development as well as stress responses. Wolfberry (Lycium barbarum L.) is an important traditional medicinal and food supplement in China, and its genome has recently been released. However, comprehensive studies of BBX genes in Lycium species are lacking. In this study, 28 LbaBBX genes were identified and classified into five clades by a phylogeny analysis with BBX proteins from Arabidopsis thaliana and the LbaBBXs have similar protein motifs and gene structures. Promoter cis-regulatory element prediction revealed that LbaBBXs might be highly responsive to light, phytohormone, and stress conditions. A synteny analysis indicated that 23, 20, 8, and 5 LbaBBX genes were orthologous to Solanum lycopersicum, Solanum melongena, Capsicum annuum, and Arabidopsis thaliana, respectively. The gene pairs encoding LbaBBX proteins evolved under strong purifying selection. In addition, the carotenoid content and expression patterns of selected LbaBBX genes were analyzed. LbaBBX2 and LbaBBX4 might play key roles in the regulation of zeaxanthin and antheraxanthin biosynthesis. Overall, this study improves our understanding of LbaBBX gene family characteristics and identifies genes involved in the regulation of carotenoid biosynthesis in wolfberry.

Anti-Fatigue Effects of Lycium barbarum Polysaccharide and Effervescent Tablets by Regulating Oxidative Stress and Energy Metabolism in Rats.

The purpose of this study was to investigate the anti-fatigue effect of natural Lycium barbarum polysaccharide (LBP) during exercise, develop a functional anti-fatigue effervescent tablet by applying LBP to practical products, and help patients who have difficulty swallowing conventional tablets or capsules. LBP was extracted with water, and DEAE-52 cellulose was used for purification. The chemical structure and monosaccharide composition of LBP by Fourier transform infrared spectroscopy (FI-IR) and ion chromatography (IC). Lycium barbarum polysaccharide effervescent tablets (LBPT) were prepared by mixing LBP and an excipient. Animal experiments showed that LBP and LBPT significantly increased the exhaustive swimming time in rats. LBP and LBPT improved biochemical markers in rat serum, such as lactic acid and creatine kinase, enhanced the antioxidant capacity of rat muscle, and reversed the decrease in serum glucose, ATP and glycogen content caused by exercise. Transmission electron microscopy showed that LBP and LBPT increased the density of mitochondria in rat liver. In addition, molecular experiments showed that LBP and LBPT could improve oxidative stress caused by exercise by regulating the Nrf2/HO-1 signaling pathway and regulating energy metabolism via the AMPK/PGC-1α signaling pathway.

Protective Effect of Lycium ruthenicum Polyphenols on Oxidative Stress against Acrylamide Induced Liver Injury in Rats.

Acrylamide (ACR) is formed during tobacco and carbohydrate-rich food heating and is widely applied in many industries, with a range of toxic effects. The antioxidant properties of Lycium ruthenicum polyphenols (LRP) have been established before. This study aimed to research the protective effect of LRP against ACR-induced liver injury in SD rats. Rats were divided into six groups: Control, ACR (40 mg/kg/day, i.g.), LRP (50, 100, and 200 mg/kg/day, i.g.) plus ACR, and LRP groups. After 19 days, we evaluated oxidative status and mitochondrial functions in the rat's liver. The results showed that glutathione (GSH) and superoxide dismutase (SOD) levels increased after LRP pretreatment. In contrast, each intervention group reduced reactive oxygen species (ROS) and malondialdehyde (MDA) levels compared to the ACR group. Meanwhile, alanine aminotransferase (ALT), aspartate aminotransferase (AST), liver mitochondrial ATPase activity, mRNA expression of mitochondrial complex I, III, and expression of nuclear factor-erythroid 2-related factor 2 (Nrf2) and its downstream proteins were all increased. This study suggested that LRP could reduce ACR-induced liver injury through potent antioxidant activity. LRP is recommended as oxidative stress reliever against hepatotoxicity.

Berberis lycium fruit extract and its phytoconstituents berberine and rutin mitigate collagen-CFA-induced arthritis (CIA) via improving GSK3ß/STAT/Akt/MAPKs/NF-κB signaling axis mediated oxi-inflammation and joint articular damage in murine model.

Rheumatoid arthritis (RA), a chronic auto-immune disease, is often result of persistent and misdirectional inflammation and cannot be effectually resolved by single-target selective drugs. Present study attempted to uncover anti-arthritic efficacy and governing molecular mechanism of BLFE and its phytoconstituents berberine and rutin, with focus on dysregulated oxi-inflammation and structural integrity during articular damage using Collagen II-CFA-induced RA mice model. NMR-based phytometabolomic analysis revealed presence of phenolics and alkaloids such as berberine and rutin. BLFE, rutin and berberine remarkably mitigated Collagen II-CFA-induced disease severity index, articular damage, immune cells influx and pannus formation. An effective decrease in levels of TNF-α, IL-6, IL-1ß, IFN-γ, IL-13, IL-17, MMPs, RORγt, Ob-cadherin, Cox-2, iNOS and enhancement in IL-10, IL-4 and IL-5, BMP-6/7 was observed in BLFE, rutin and berberine treatments. Molecular mechanistic analysis demonstrated reduction in expression of p-STAT-1/3, p-PI3K, p-Akt, p-JNK, p-p38, p-IκB, p-NF-κB and ß-catenin via BLFE, rutin and berberine. Furthermore, reduced activation of p-ERK and p-GSK3ß and enhanced splenic Tregs was only noticed in BLFE and berberine. Thus, the signifying presence of these phytoconstituents could contribute to the above-mentioned findings. These findings imply that BLFE could be beneficial for assuaging deleterious aspects of RA mediated via perturbed inflammation.

Anthocyanin extract from Lycium ruthenicum enhanced production of biomass and polysaccharides during submerged fermentation of Agaricus bitorquis (Quél.) Sacc. Chaidam.

Agaricus bitorquis (Quél.) Sacc. Chaidam (ABSC) is a wild edible fungus uniquely found in the Tibet Plateau. ABSC is rich in polysaccharides that are considered biologically active. This study aimed to determine the feasibility of enhancing exopolysaccharide (EPS) production by ABSC in shake flask culture by supplementing the fermentation medium with anthocyanin extract. Different concentrations of Lycium ruthenicum Murr. (LRM) anthocyanin crude extract were tested on ABSC fermentation. The activity of phosphoglucose isomerase (PGI), phosphoglucose mutase (PGM), and phosphomannose isomerase (PMI), enzymes presumably involved in EPS synthesis by ABSC, was determined. ABSC transcriptomic profile in response to the presence of anthocyanins during fermentation was also investigated. LRM anthocyanin crude extract (0.06 mg/mL) was most effective in increasing EPS content and mycelial biomass (by 208.10% and 105.30%, respectively, P < 0.01). The activity of PGI, PGM, and PMI was increased in a medium where LRM anthocyanin extract and its main components (proanthocyanidins and petunia anthocyanin) were added. RNA-Seq analysis showed that 349 genes of ABSC were differentially expressed during fermentation in the medium containing anthocyanin extract of LRM; 93 genes were up-regulated and 256 genes down-regulated. From gene ontology enrichment analysis, differentially expressed genes were mostly assigned to carbohydrate metabolism and signal transduction categories. Collectively, LRM anthocyanins extract positively affected EPS production and mycelial biomass during ABSC fermentation. Our study provides a novel strategy for improving EPS production and mycelial growth during ABSC liquid submerged fermentation.

Integrative Analysis of Transcriptome and Metabolome Reveals Salt Stress Orchestrating the Accumulation of Specialized Metabolites in Lycium barbarum L. Fruit.

Salt stress seriously affects yield and quality of crops. The fruit of Lycium barbarum (LBF) is extensively used as functional food due to its rich nutrient components. It remains unclear how salt stress influences the quality of LBF. In this study, we identified 71 differentially accumulated metabolites (DAMs) and 1396 differentially expressed genes (DEGs) among ripe LBF with and without 300 mM of NaCl treatment. Pearson correlation analysis indicated that the metabolomic changes caused by salt stress were strongly related to oxidoreductases; hydrolases; and modifying enzymes, in particular, acyltransferases, methyltransferases and glycosyltransferases. Further analysis revealed that salt stress facilitated flavonoid glycosylation and carotenoid esterification by boosting the expression of structural genes in the biosynthetic pathways. These results suggested that salt stress prompts the modification of flavonoids and carotenoids to alleviate ROS damage, which in turn improves the quality of LBF. Our results lay a solid foundation for uncovering the underlying molecular mechanism of salt stress orchestrating LBF quality, and the candidate genes identified will be a valuable gene resource for genetic improvement of L. barbarum.

Yeast Synthetic Biology for the Production of Lycium barbarum Polysaccharides.

The fruit of Lycium barbarum L. (goji berry) is used as traditional Chinese medicine, and has the functions of immune regulation, anti-tumor, neuroprotection, anti-diabetes, and anti-fatigue. One of the main bioactive components is L. barbarum polysaccharide (LBP). Nowadays, LBP is widely used in the health market, and it is extracted from the fruit of L. barbarum. The planting of L. barbarum needs large amounts of fields, and it takes one year to harvest the goji berry. The efficiency of natural LBP production is low, and the LBP quality is not the same at different places. Goji berry-derived LBP cannot satisfy the growing market demands. Engineered Saccharomyces cerevisiae has been used for the biosynthesis of some plant natural products. Recovery of LBP biosynthetic pathway in L. barbarum and expression of them in engineered S. cerevisiae might lead to the yeast LBP production. However, information on LBP biosynthetic pathways and the related key enzymes of L. barbarum is still limited. In this review, we summarized current studies about LBP biosynthetic pathway and proposed the strategies to recover key enzymes for LBP biosynthesis. Moreover, the potential application of synthetic biology strategies to produce LBP using engineered S. cerevisiae was discussed.

A Comparative Study on Polyphenolic Composition of Berries from the Tibetan Plateau by UPLC-Q-Orbitrap MS System.

Five traditional medicinal food from the Tibetan plateau including Nitraria tangutorum Bobrov (NT), Hippophae rhamnoides L. (HR), Lycium ruthenicum Murray (LR), Lycium barbarum L. (LB) and Rubus corchorifolius L.f. (RC) are rich in phenolic compounds. However, the detailed studies about the phenolic compounds remain scarce. Therefore, we established a rapid method for the simultaneous identification and quantification of the phenolic compounds from berries via Ultra Performance Liquid Chromatography-Quadruple-Orbitrap MS system (UPLC-Q-Orbitrap MS). This method was verified from many aspects including detection limit, quantification limit, precision, repeatability, stability, average recovery rate and recovery range, and then was used to analyze the phenolic compounds in these five species of berries. Finally, a total of 21 phenolic compounds were directly identified by comparing the retention time and exact mass, of which 14 compounds were identified by us for the first time in berries from the Tibetan plateau, including one flavonoid aglycone (myricetin), 11 phenolic acids (gallic acid, protocatechuate, chlorogenic acid, vanillic acid, caffeic acid, syringic acid, p-coumaric acid, ferulic acid, 2-hydroxybenzeneacetic acid and ellagic acid), one flavanol (catechin) and one dihydrochalcone flavonoid (phloretin). Quantitative results showed that rutin, myricetin, quercetin and kaempferol were the main flavonoids. Moreover, a variety of phenolic acid compounds were also detected in most of the berries from the Tibetan plateau. Among these compounds, the contents of protocatechuate and chlorogenic acid were high, and high levels of catechin and phloretin were also detected in these plateau berries.

Preparative Separation of Flavonoids from Goji Berries by Mixed-Mode Macroporous Adsorption Resins and Effect on Aß-Expressing and Anti-Aging Genes.

Flavonoids are the main constituents of Goji berries and have good biological and pharmacological activities. The mixed-mode macroporous adsorption resins (MARs) for purification of flavonoids from Goji berries through computer-assisted calculation of the molecular size of flavonoids and the precise matching of MAR physical and chemical properties was firstly developed in the present study. Ten varieties of MARs with suitable molecular dimensions and polarities were used for investigating the adsorption/desorption behaviors of the flavonoids. Both AUKJ-1 and BWKX-1 showed higher separation efficiency than other MARs and then were mixed in different ratios to constitute a mixed-mode macroporous adsorption resin to obtain the optimal adsorption phase. Under optimal conditions, total flavonoid content of purified flavonoid (p-FLA) extract increased from 0.97% to 36.88% after one purification. The p-FLA extract from Goji berries significantly improved the expression of six genes with anti-aging effects and played an important role in aging-related Alzheimer's disease by down-regulating Aß expression.