Extraction, purification, structural characterization and pharmacological activities of polysaccharides from sea buckthorn (Hippophae rhamnoides L.): A review.

ETHNOPHARMACOLOGICAL RELEVANCE: Sea buckthorn (Hippophae rhamnoides L.) is an edible fruit with a long history in China as a medicinal plant. The fruits of H. rhamnoides are rich in a variety of nutrients and pharmacological active compounds. As one of the most important active ingredients in sea buckthorn, polysaccharides have attracted the attention of researchers due to their antioxidant, anti-fatigue, and liver protective qualities. AIM OF THE REVIEW: This review summarizes recent studies on extraction, purification, structural characterization and pharmacological activities of polysaccharides from sea buckthorn. In addition, the relationship between the structure and the activities of sea buckthorn polysaccharides (SBPS) were discussed. This review would provide important research bases and up-to-date information for the future in-depth development and application of sea buckthorn polysaccharides in the field of pharmaceuticals and functional foods. MATERIALS AND METHODS: By inputting the search term "Sea buckthorn polysaccharides", relevant research information was obtained from databases such as Web of Science, Google Scholar, PubMed, China Knowledge Network (CNKI), China Master Theses Full-text Database, and China Doctoral Dissertations Full-text Database. RESULTS: The main extraction methods of SBPS include hot water extraction (HWE), ultrasonic assisted extraction (UAE), microwave-assisted extraction (MAE), flash extraction (FE), and ethanol extraction. More than 20 polysaccharides have been isolated from sea buckthorn fruits. The chemical structures of sea buckthorn polysaccharides obtained by different extraction, isolation, and purification methods are diverse. Polysaccharides from sea buckthorn display a variety of pharmacological properties, including antioxidant, anti-fatigue, liver protection, anti-obesity, regulation of intestinal flora, immunoregulation, anti-tumor, anti-inflammatory, and hypoglycemic activities. CONCLUSIONS: Sea buckthorn has a long medicinal history and characteristics of an ethnic medicine and food. Polysaccharides are one of the main active components of sea buckthorn, and they have received increasing attention from researchers. Sea buckthorn polysaccharides have remarkable pharmacological activities, health benefits, and broad application prospects. In addition, further exploration of the chemical structure of SBPS, in-depth study of their pharmacological activities, identification of their material basis, characterization of disease resistance mechanisms, and potential health functions are still directions of future research. With the accumulation of research on the extraction and purification processes, chemical structure, pharmacological effects, molecular mechanisms, and structure-activity relationships, sea buckthorn polysaccharides derived from natural resources will ultimately make significant contributions to human health.

Dynamic analysis of physiological indices and transcriptome profiling revealing the mechanisms of the allelopathic effects of phenolic acids on Pinellia ternata.

Pinellia ternata (Thunb.) is a famous traditional Chinese medicine with high medicinal value, but its culture is strongly hindered by the continuous cropping obstacles (CCO) which are tightly associated with allelopathic effects. Deciphering the response mechanisms of P. ternata to allelochemicals is critical for overcoming the CCO. Here, we elucidate the response of P. ternata to phenolic acids treatment via physiological indices, cellular approaches, and transcriptome analysis. Phenolic acids showed a significant effect on the growth of P. ternata seedlings, similar to the phenotype of continuous cropping. Cellular analysis demonstrated that phenolic acids remarkably induced root cell death. Physiological analysis revealed that phenolic acids induced the overaccumulated of H2O2 and O 2 - in root cells. However, two exogenous antioxidants (L-ascorbic acid and ß-gentiobiose) aid in the scavenging of over-accumulated H2O2 and O 2 - by promoting the antioxidant enzyme activity such as superoxide dismutase (SOD), ascorbate peroxidase (APX), and catalase (CAT). Transcriptome analysis demonstrated that differentially expressed genes (DEGs) related to the cell wall degeneration and reactive oxygen species (ROS) metabolism were upregulated by phenolic acid treatment. In addition, downregulated DEGs involved in sucrose and starch metabolism and phenylpropanoid biosynthesis pathways decreased the key metabolites contents. Taken together, phenolic acids caused root cell death by inducing the overaccumulation of H2O2 and O 2 - , and L-ascorbic acid and ß-gentiobiose effectively alleviated ROS stress. The present study elucidates the underlying mechanism of the allelopathic effect of phenolic acids, offers valuable information for further understanding the mechanism of CCO, and could contribute to improving guidance for further P. ternata production.

Pinellia ternata (Thunb.) Breit: A review of its germplasm resources, genetic diversity and active components.

ETHNOPHARMACOLOGICAL RELEVANCE: The medicinal plant Pinellia ternata has been widely used in China, Korea, and Japan and has been demonstrated to be highly effective for treating cough, vomiting, infection, and inflammatory diseases. Modern pharmacological investigations have demonstrated its multiple activities, such as antitussive, expectorant, antiemetic, antitumor, antibacterial, and sedative-hypnotic activities. AIM OF THE REVIEW: This review aims to summarize the information about the biological traits, genetic diversity, active components, and continuous cropping obstacle of P. ternata in order to improve its use. MATERIALS AND METHODS: In this review, the relevant literature was gathered by using Pinellia ternata, genetic diversity, active components, and continuous cropping obstacle as the keywords from Google Scholar, PubMed, Springer Link, the Wiley online library, SciFinder, SCOPUS, Baidu Scholar, China national knowledge infrastructure (CNKI), and WANFANF DATA (up to April 2020). RESULTS: P. ternata is the most widely used herb in the Pinellia genus to treat several diseases. The genetic diversity of P. ternata has been extensively studied, and its high genetic diversity level in China has been demonstrated. Modern pharmacological research has indicated that amino acids, alkaloids, and polysaccharides are the main active components supporting P. ternata's medicinal effects. However, an efficient method for determining its active components is still unavailable. The method used to evaluate Pinelliae Rhizoma (PR) quality standards should be further optimized. The continuous cropping obstacle has a significant effect on the quantity and quality of P. ternata. The underlying mechanism of the continuous cropping obstacle needs to be further explored. CONCLUSIONS: P. ternata has emerged as a valuable source of traditional medicine. Some uses of P. ternata in medicine have been validated by pharmacological investigations. However, a more efficient analytical method should be established to evaluate the quality of PR based on multiple quality markers. Furthermore, high-performance liquid chromatography (HPLC) and DNA barcoding should be introduced to identify the authenticity of PR. In addition, the genes involved in the metabolic synthesis pathways of the main active components, population genetic relationships, the quality control of processed PR, and the continuous cropping obstacle need to be further elucidated. We hope this review will allow for better utilization of this valuable herb.

Physiological, transcriptional, and metabolic alterations in spaceflight-subjected Senna obtusifolia.

Senna obtusifolia is a widely used medicinal herb in Asian countries. To select elite cultivars, S. obtusifolia seeds were carried by "ShenZhou Ⅷ" recoverable satellite to space. Three spaceflight-subjected lines (SP-lines), namely QC10, QC29, QC46, and their ground control line (GC-line) were cultivated on the ground. Previous studies demonstrated that biological traits and secondary metabolites are different between SP-lines and GC-line. Here, we combined physiological, transcriptional, and metabolic studies to compare the differences between SP-lines and GC-line. The results showed that activities of superoxide dismutase (SOD), peroxidase (POD), catalase (CAT), ascorbate peroxidase (APX), and monodehydroascorbate reductase (MDHAR) were dramatically increased in SP-lines as compared to that of GC-line. Transcript levels of SOD, POD, CAT, APX, and MDHAR were significantly up-regulated in SP-lines. Malondialdehyde (MDA) and hydrogen peroxide (H2O2) contents decreased in SP-lines. Seed yields of QC29 and QC46 were considerably higher than that of GC-line. Besides, QC29 had significantly higher aurantio-obtusin content. Pearson correlation coefficient analysis revealed positive relationships between POD and aurantio-obtusin, as well as APX and aurantio-obtusin. In conclusion, SP-lines have higher antioxidant gene expression level and antioxidant enzyme activity as compared to that of GC-line. With higher seed yield and aurantio-obtusin content, QC29 can be used to breed elite S. obtusifolia cultivars. This study provides a new insight in SP-lines and paves the way to breed elite S. obtusifolia cultivars in the future.

Remediation of deterioration in microbial structure in continuous Pinellia ternata cropping soil by crop rotation.

Pinellia ternata is a traditional Chinese herb that suffers from continuous cropping (CC), which significantly decreases both yield and quality. The influence of CC on the microbiome in P. ternata rhizosphere and the effects of remediation on microbiota by rotational cropping (CR) were assessed by Illumina high-throughput sequencing technology. CC tends to decrease the α-diversities as a function of cultivation time, whereas CR tends to increase them. Differentially abundant analysis showed that microbial structure was important in maintaining the health status of P. ternata rhizosphere. Results suggested that CC soils were mainly enriched for Pseudomonas, Rhizobium, and Streptophyta operational taxonomic units (OTUs), while the CR soils were mainly enriched for Rhizobium, Pseudomonas, Flavobacterium, Sphingomonas, Rhizobacter, and Arthrobacter OTUs. On the basis of the community dissimilarities, we grouped all sample replicates into three post hoc clusters in which soils were defined as healthy, health-suppressed, and health-depressed soils. The three soil types represented different soil physicochemical properties. The activities of the microbiome features, including ammonia oxidizer, sulfate reducer, nitrite reducer, dehalogenation, xylan degrader, sulfide oxidizer, nitrogen fixation, atrazine metabolism, chitin degradation, degraded aromatic hydrocarbons, and chlorophenol degradation, were also considerably different among the three soils.

Identification of seeds based on molecular markers and secondary metabolites in Senna obtusifolia and Senna occidentalis.

BACKGROUND: Senna obtusifolia and Senna occidentalis (Leguminosae), whose seeds have similar appearance and chemical constituents, are easily confused in using their seeds. To elucidate the similarities and differences between S. obtusifolia seeds and S. occidentalis seeds, three molecular markers and high performance liquid chromatography (HPLC) were employed to evaluate the seeds characteristics of these two medicinal herbs. RESULTS: The results showed that selected 3 ISSR and 7 SCoT primers could distinguish S. obtusifolia seeds from S. occidentalis seeds based on the specific band and UPGMA dendrogram. ITS2 sequence indicated that the intra-specific similarity of 20 S. obtusifolia and 16 S. occidentalis was 99.79 and 100.0%, respectively, while the inter-specific similarity between S . obtusifolia and S. occidentalis was 89.58%. Although phylogenetic analysis revealed that these two species had a close relationship, they were assigned to different branches. HPLC fingerprint results showed that seeds of S. obtusifolia and S. occidentalis shared some secondary metabolites, but aurantio-obtusin was not detected in S. occidentalis seeds which could differentiate S. obtusifolia seeds from S. occidentalis seeds. CONCLUSIONS: The present study not only compared the seeds characters of S. obtusifolia and S. occidentalis from molecular and secondary metabolites levels, but also provided a convenient method to identify S. obtusifolia seeds and S. occidentalis seeds effectively.

Identification and Characterization of Salvia miltiorrhizain miRNAs in Response to Replanting Disease.

Replanting disease is a major factor limiting the artificial cultivation of the traditional Chinese medicinal herb Salvia miltiorrhiza. At present, little information is available regarding the role of miRNAs in response to replanting disease. In this study, two small RNA libraries obtained from first-year (FPR) and second-year plant (SPR) roots were subjected to a high-throughput sequencing method. Bioinformatics analysis revealed that 110 known and 7 novel miRNAs were annotated in the roots of S. miltiorrhiza. Moreover, 39 known and 2 novel miRNAs were identified and validated for differential expression in FPR compared with SPR. Thirty-one of these miRNAs were further analyzed by qRT-PCR, which revealed that 5 miRNAs negatively regulated the expression levels of 7 target genes involved in root development or stress responses. This study not only provides novel insights into the miRNA content of S. miltiorrhiza in response to replanting disease but also demonstrates that 5 miRNAs may be involved in these responses. Interactions among the differentially expressed miRNAs with their targets may form an important component of the molecular basis of replanting disease in S. miltiorrhiza.

Phosphate starvation promoted the accumulation of phenolic acids by inducing the key enzyme genes in Salvia miltiorrhiza hairy roots.

KEY MESSAGE: Phosphate starvation increased the production of phenolic acids by inducing the key enzyme genes in a positive feedback pathway in Saliva miltiorrhiza hairy roots. SPX may be involved in this process. Salvia miltiorrhiza is a wildly popular traditional Chinese medicine used for the treatment of coronary heart diseases and inflammation. Phosphate is an essential plant macronutrient that is often deficient, thereby limiting crop yield. In this study, we investigated the effects of phosphate concentration on the biomass and accumulation of phenolic acid in S. miltiorrhiza. Results show that 0.124 mM phosphate was favorable for plant growth. Moreover, 0.0124 mM phosphate was beneficial for the accumulation of phenolic acids, wherein the contents of danshensu, caffeic acid, rosmarinic acid, and salvianolic acid B were, respectively, 2.33-, 1.02-, 1.68-, and 2.17-fold higher than that of the control. By contrast, 12.4 mM phosphate inhibited the accumulation of phenolic acids. The key enzyme genes in the phenolic acid biosynthesis pathway were investigated to elucidate the mechanism of phosphate starvation-induced increase of phenolic acids. The results suggest that phosphate starvation induced the gene expression from the downstream pathway to the upstream pathway, i.e., a feedback phenomenon. In addition, phosphate starvation response gene SPX (SYG1, Pho81, and XPR1) was promoted by phosphate deficiency (0.0124 mM). We inferred that SPX responded to phosphate starvation, which then affected the expression of later responsive key enzyme genes in phenolic acid biosynthesis, resulting in the accumulation of phenolic acids. Our findings provide a resource-saving and environmental protection strategy to increase the yield of active substance in herbal preparations. The relationship between SPX and key enzyme genes and the role they play in phenolic acid biosynthesis during phosphate deficiency need further studies.