Flavonoid Glycosides and Their Derivatives from the Herbs of Scorzonera austriaca Wild

The genus Scorzonera L. (Asteraceae): A comprehensive review on traditional uses, phytochemistry, pharmacology, toxicology, chemotaxonomy, and other applications

ETHNOPHARMACOLOGICAL RELEVANCE

The genus Scorzonera L. comprises of approximately 175 species, which are mainly distributed in temperate and arid regions of Central Europe, Central Asia, and Africa. Twenty-nine Scorzonera traditional ethnomedicines have been used for treating colds and fevers, pulmonary diseases, asthma, dyspepsia, malignant stomach neoplasia, liver disorder, jaundice, kidney diseases, mastitis, women's vaginitis, herpes zoster, poisonous ulcers, rheumatic pain, diabetic, atherosclerosis, headache, hypertension, dysentery, pregnant vomiting, snakebites, etc. AIM OF THE REVIEW: This review aims to systematically evaluate the genus Scorzonera over its ethnomedicinal uses, phytochemistry, pharmacology, and toxicology, discuss the relationship between traditional uses, phytochemistry and pharmacological properties, and put forward some suggestions to promote further development and utilization of Scorzonera.

MATERIALS AND METHODS

This review is based on published scientific research works obtained from the following databases: Elsevier, Web of Science, PubMed, Springer, Wiley, Taylor & Francis, Google Scholar, CNKI, Baidu Scholar, ResearchGate, and others (the Flora of China, 1997 edition; Chinese herbal books, PhD dissertation and Master thesis in Chinese).

RESULTS

The genus 81 Scorzonera plants have been studied for their traditional usage, phytochemistry, and pharmacology. Altogether 421 chemical constituents are isolated from the 54 species of Scorzonera, which include sesquiterpenoids, monoterpenes, diterpenes, triterpenoids, steroids, quinic acid derivatives, flavonoids, cumarinoids, lignanoids, phenylpropanoids, stilbene derivatives, benzylphthalides, kava lactones, phenolics, aliphatic acids, phthalic acids, alkanes, vitamins, sugars, alkaloids, and other constitutes. Besides those listed above, there are also volatile oils, polysaccharides, tannins, amino acids, enzymes, and inorganic elements. The extracts and compounds extracted from 55 Scorzonera species exhibit extensive pharmacological activities, such as anti-inflammatory, antinociceptive, wound healing, anti-cancer, hepatoprotective, anti-microbial, anti-ulcerogenic, antidiarrheal, antidiabetic, hypolipidemic, antioxidant, repairing cerebral ischemia, antidepressant, immunomodulatory activities, enzyme inhibitory effects, etc. Clinical applications strongly indicate that certain species are effective in treating herpes zoster and pregnancy resistance. Certain species are studied over applicationssuch as pharmacokinetic and histological distribution, and toxicity, the product extraction process, quick-freezing processing technology, synthesized metabolites, etc. Chemotaxonomy is also discussed on Scorzonera.

CONCLUSION

This review provides information on traditional usage, phytochemistry, pharmacology, toxicology, chemotaxonomy, other applications aspects, and future prospects of the genus Scorzonera. However, only around one third of Scorzonera species have been studied so far. This review may be used as the basis for future endeavors, including further biological and chemical investigations, and efforts of seeking more applications.

Identification and Quantification of Flavonoids in Okra (Abelmoschus esculentus L. Moench) and Antiproliferative Activity In Vitro of Four Main Components Identified

Okra is a kind of flavonoid-rich food which was reported to have a variety of health functions. Flavonoids are the major polyphenolic compounds in okra and are thought to play a role in reducing the risk of disease. The aim of this study was to isolate and identify the flavonoids composition in okra pods and explore the activity of the main flavonoids components identified on inhibiting tumor cell proliferation in vitro. Six individual flavonoids were identified by HPLC-MS/MS: quercetin-3-gentiobioside (Q3G), quercetin-3-sambubioside (Q3S), rutin, quercetin-7-glucoside (Q7G), isoquercitrin (ISO) and quercetin-3-malonylglucoside (Q3M), which were all separated well within 30 min. The analytical method was validated by the recovery of spiked samples and so on. Moreover, four main flavonoids components, namely Q3G, Q3S, ISO and Q3M, exhibited significant (p < 0.05) inhibition of NCI-N87, A375, A549 cells proliferation (25−100 μmol/L) and of HFLS-RA (200−300 μmol/L) in different levels, according to MTT method, respectively. It is demonstrated that the flavonoids components of okra exhibited a noteworthy development prospect as a possible nutraceutical dietary supplement.

Complete genome sequence and genome organization of scorzonera virus A (SCoVA), a novel member of the genus Potyvirus

The complete genomic sequence of scorzonera virus A (SCoVA) from a Scorzonera austriaca Willd. plant in South Korea was determined by high-throughput sequencing and confirmed by Sanger sequencing. The SCoVA genome contains 9867 nucleotides, excluding the 3'-terminal poly(A) tail. The SCoVA genome structure is typical of potyviruses and contains a single open reading frame encoding a large putative polyprotein of 3168 amino acids. Pairwise comparison analysis of the complete genome and polyprotein sequences of SCoVA with those of other potyviruses showed that they shared the highest nucleotide and amino acid sequences identity (54.47% and 49.57%, respectively) with those of lettuce mosaic virus (GenBank accession number KJ161185). Phylogenetic analysis of the amino acid sequence of the polyprotein confirmed that SCoVA belongs to the genus Potyvirus. These findings suggest that SCoVA should be considered a novel member of the genus Potyvirus, family Potyviridae.

Phytochemical Composition and Biological Activities of Scorzonera Species

The genus Scorzonera comprises nearly 200 species, naturally occurring in Europe, Asia, and northern parts of Africa. Plants belonging to the Scorzonera genus have been a significant part of folk medicine in Asia, especially China, Mongolia, and Turkey for centuries. Therefore, they have become the subject of research regarding their phytochemical composition and biological activity. The aim of this review is to present and assess the phytochemical composition, and bioactive potential of species within the genus Scorzonera. Studies have shown the presence of many bioactive compounds like triterpenoids, sesquiterpenoids, flavonoids, or caffeic acid and quinic acid derivatives in extracts obtained from aerial and subaerial parts of the plants. The antioxidant and cytotoxic properties have been evaluated, together with the mechanism of anti-inflammatory, analgesic, and hepatoprotective activity. Scorzonera species have also been investigated for their activity against several bacteria and fungi strains. Despite mild cytotoxicity against cancer cell lines in vitro, the bioactive properties in wound healing therapy and the treatment of microbial infections might, in perspective, be the starting point for the research on Scorzonera species as active agents in medical products designed for miscellaneous skin conditions.

The evaluation of hepatoprotective effects of flavonoids from Scorzonera austriaca Wild against CCl4-induced acute liver injury in vitro and in vivo

Scorzonera austriaca Wild is a traditional herbal medicine; however, little is known with regard to the effect of flavonoids from S. austriaca (FSA) on liver injury induced by Carbon tetrachloride (CCl₄), especially the mechanism remains unknown. Therefore, our paper was designed to investigate the hepatoprotective effect of FSA against CCl₄-induced acute liver injury in vitro and in vivo, with focus on its potential mechanism. The purity of FSA prepared by using polyporous resin column chromatography could reach 94.5%, and seven flavonoid compounds in FSA were identified by using LC-ESI-MS analysis. In vivo results showed that FSA markedly decreased the levels of aspartate aminotransferase (AST), alanine aminotransferase (ALT), lactate dehydrogenase (LDH) and malonaldehyde (MDA) and increased the contents of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px). Furthermore, in vivo and in vitro results confirmed that FSA could inhibit inflammatory response, as evidenced by decreasing the levels of tumor necrosis factor alpha (TNF-α) and interleukin-6 (IL-6) through inactivating toll-like receptor-4/nuclear factor-κB (TLR4/NF-κB) signaling pathway. FSA activated autophagy by increasing the ratio of LC3B-II/I and decreasing the protein level of p62 so as to exert its hepatoprotective effect. In general, these evidences suggested that FSA is likely to serve as a potential material for the drugs against chemical hepatic injury.

Flavonoid pattern inheritance in the allopolyploid Spartina anglica - Comparison with the parental species S. maritima and S. alterniflora

The invasive species Spartina anglica arose in Europe by a cross between the Afro-European species S. maritima (native, paternal ancestor) and the introduced North American S. alterniflora (invasive, maternal ancestor). Aqueous methanolic extracts were prepared from plant tissue for chemotaxonomical comparison between the three species and determination of the phenolic pattern inheritance in S. anglica. A total of 20 phenolic compounds were detected in the aerial tissues of S. anglica and S. alterniflora, but only seven in S. maritima. They were isolated from their respective crude extracts, and their structures were determined according to spectroscopic data analysis and chemical evidence. They all belong to the flavonoid class, with 13 of them identified as C-glycoflavonoid and seven as O-glycoflavonoid. All these products were detected for the first time from S. anglica, fourteen of them for the first time from S. alterniflora, and three of them for the first time from S. maritima. The individual concentrations in the three species were determined by quantitative HPLC. The two parental species were found to differ markedly in their foliar phenolic fingerprint, whereas that of S. anglica showed a clear maternal dominance. Eight of the fourteen major compounds identified were of maternal origin among which, six were over-expressed, only three were from paternal origin but under-regulated, while two originated from the two parents. As far as we know, this work represents the first exhaustive report of the phenolic fingerprints of S. alterniflora and S. anglica and of the phenolic pattern inheritance in S. anglica. The similarity in the phenolic chemistry of the introduced and invasive S. alterniflora to its progeny could play a role in the physiological vigour and invasion success of S. anglica. This work provide a foundation for further studies, considering the reported biological activities of C-glycosidic flavonoids and tricin derivatives, and the lack of knowledge of the ecological chemistry of the genus Spartina.

Phytochemical Analysis of Podospermum and Scorzonera n-Hexane Extracts and the HPLC Quantitation of Triterpenes

Previously tested n-hexane extracts of the Scorzonera latifolia showed promising bioactivity in vivo. Because triterpenes could account for this activity, n-hexane extracts were analyzed by HPLC to identify and quantify the triterpenes as the most abundant constituents. Other Scorzonera and Podospermum species, potentially containing triterpenic aglycones, were included in the study. An HPLC method for simultaneous determination of triterpene aglycones was therefore developed for analysis of Podospermum and Scorzonera species. n-Hexane extracts of root and aerial parts of S. latifolia, ten other Scorzonera species and two Podospermum species were studied to compare the content of triterpenes. HPLC was used for the qualitative and quantitative analysis of α-amyrin, lupeol, lupeol acetate, taraxasteryl acetate, 3-β-hydroxy-fern-7-en-6-one acetate, urs-12-en-11-one-3-acetyl, 3-β-hydroxy-fern-8-en-7-one acetate, and olean-12-en-11-one-3-acetyl. Limits of detection and quantification were determined for each compound. HPLC fingerprinting of n-hexane extracts of Podospermum and Scorzonera species revealed relatively large amounts of triterpenes in a majority of investigated taxa. Lupeol, lupeol acetate, and taraxasteryl acetate were found in a majority of the species, except S. acuminata. The presence of α-amyrin, 3β-hydroxy-fern-7-en-6-one-acetate, urs-12-en-11-one-3-acetyl, 3β-hydroxy-fern-8-en-7-one-acetate, and olean-12-en-11-one-3-acetyl was detected in varying amounts. The triterpene content could correlate with the analgesic and anti-inflammatory activity of Scorzonera, which was previously observed and Scorzonera species that have been determined to contain triterpenes in large amounts and have not yet been tested for their analgesic activity should be tested for their potential analgesic and anti-inflammatory potential. The presented HPLC method can be used for analysis of triterpene aglycones, for example dedicated to chemosystematic studies of the Scorzonerinae.

Recent advances in pharmacokinetics approach for herbal medicine

Traditional Chinese Medicine (TCM), an indispensable part of herbal medicine, has been used for treating many diseases and/or symptoms for thousands of years.