A new cyclic polyketide and other constituents from Ononis spinosa growing wildly in Jordan and their antioxidant activity

The new cyclic polyketide 7,9,11-trihydroxytetracos-2-eneoic acid δ-lactone (1), together with other eleven known compounds, were isolated from Ononis spinosa, growing wildly in Jordan. All isolated compounds were identified by thorough investigation of their spectral data including NMR and HRESIMS. Antioxidant activity testing of puerol B, specionin and the new cyclic polyketide revealed that puerol B had the highest DPPH radical scavenging activity (IC₅₀ 0.09 ± 0.006 mg/ml) as compared to α-tocopherol (IC₅₀ 0.039 ± 0.0006 mg/ml), while specionin had the highest ABTS radical scavenging power (IC₅₀ 0.013 ± 0.0008 mg/ml) as compared to α-tocopherol and ascorbic acid (IC₅₀ 0.042 ± 0.0004; 0.026 ± 0 .0007 mg/ml; respectively).

Phytochemical Profile and Microbiological Activity of Some Plants Belonging to the Fabaceae Family

This study aimed to investigate the chemical composition and the activity against Staphylococcus aureus (S. aureus) (ATCC 25923), Streptococcus pyogenes (S. pyogenes) (ATCC 19615), Escherichia coli (E. coli) (ATCC 25922), Pseudomonas aeruginosa (P. aeruginosa) (ATCC 27853), Shigella flexneri (S. flexneri) (ATCC 12022), Salmonella typhimurium (S. typhimurium) (ATCC 14028), Haemophillus influenzae (H. influenza) type B (ATCC 10211) and two fungal strains: Candida albicans (C. albicans) (ATCC 10231) and Candida parapsilopsis (C. parapsilopsis) (ATCC 22019) of the extracts obtained from Melilotus officinalis (MO), Coronilla varia (CV); Ononis spinosa (OS) and Robinia pseudoacacia (RP) (Fabaceae), and to identify the chemical compounds responsible for the antimicrobial effect against the tested strains. The extracts were obtained by conventional hydroalcoholic extraction and analyzed in terms of total polyphenols using the spectrophotometric method and by liquid chromatography (LC). The results have shown that the highest polyphenols content was recorded in the RP sample (16.21 mg gallic acid equivalent GAE/g), followed by the CV (15.06 mg GAE/g), the OS (13.17 mg GAE/g), the lowest value being recorded for the MO sample (11.94 mg GAE/g). The antimicrobial testing of plant extracts was carried out using the microdilution method. The most sensitive strains identified were: E. coli, S. typhimurium, P. aeruginosa and S. pyogenes, while protocatechuic acid, gallic acid, caffeic acid, quercetin, rutin, and kaempferol were identified as the chemical compounds responsible for the antibacterial effect. The analysis of the correlation between the chemical composition and the antimicrobial effect proved a moderate (r > 0.5) positive correlation between rosmarinic acid and S. pyogenes (r = 0.526), rosmarinic acid and S. typhimurium (r = 0.568), quercetin and C. albicans (r = 0.553), quercetin and S. pyogenes (r = 0.605). Therefore, it suggested possible antimicrobial activity generated by these chemical components. The results recommend the Fabaceae plants as promising candidates for further research to develop novel natural antimicrobial drugs.

Phenolic Content and Antimicrobial and Anti-Inflammatory Effects of Solidago virga-aurea, Phyllanthus niruri, Epilobium angustifolium, Peumus boldus, and Ononis spinosa Extracts

Prostatitis is an inflammatory condition that is related to multiple infectious agents, including bacteria and fungi. Traditional herbal extracts proved efficacious in controlling clinical symptoms associated with prostatitis. In this context, the aim of the present study was to explore the efficacy of extracts from Solidago virga-aurea, Ononis spinosa, Peumus boldus, Epilobium angustifolium, and Phyllanthus niruri against bacterial (Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, Bacillus cereus) and fungi strains (Candida albicans; C. tropicalis) involved in prostatitis. Additionally, anti-mycotic effects were tested against multiple species of dermatophytes (Trichophyton rubrum, T. tonsurans, T. erinacei, Arthroderma crocatum, A. quadrifidum, A. gypseum, A. currey, and A. insingulare). Antioxidant effects were also evaluated in isolated rat prostates challenged with lipopolysaccharide (LPS), and phytochemical analyses were conducted to identify and quantify selected phenolic compounds, in the extracts. Finally, a bioinformatics analysis was conducted to predict putative human and microbial enzymes targeted by extracts’ phytocompounds and underlying the observed bio-pharmacological effects. The phytochemical analysis highlighted that rutin levels could be crucial for explaining the highest antibacterial activity of P. boldus extract, especially against E. coli and B. cereus. On the other hand, in the E. angustifolium extract, catechin concentration could partially explain the highest efficacy of this extract in reducing lipid peroxidation, in isolated rat prostates stimulated with LPS. Concluding, the results of the present study showed moderate antimicrobial and anti-inflammatory effects induced by water extracts of S. virga-aurea, P. boldus, E. angustifolium, P. niruri, and O. spinosa that could be related, at least partially, to the phenolic composition of the phytocomplex.

Root Extracts From Ononis spinosa Inhibit IL-8 Release via Interactions With Toll-Like Receptor 4 and Lipopolysaccharide

Extracts from the roots of Ononis spinosa L. (restharrow roots) are traditionally used for the treatment of patients with urinary tract infections due to its mild diuretic activity, caused by the inhibition of renal human hyaluronidase-1 by isoflavonoids. Preliminary studies also indicated anti-inflammatory effects. The following study aimed at investigating potential anti-inflammatory effects of restharrow extracts, prepared with solvents of different polarity. A dichloromethane extract (OS1), mainly composed of isoflavonoids and triterpenes as characterized by LC-MS, showed a concentration-dependent (25–100 μg/ml) inhibition of IL-8 and TNF-α release from LPS-stimulated human neutrophils. Significant inhibition was also found for the triterpene α-onocerin and the norneolignan clitorienolactone B, isolated from OS1. Further, OS1 and both compounds significantly decreased the expression of the adhesion molecules CD11b/CD18 and conversely increased the expression of CD62L in LPS-stimulated human neutrophils. This finding corresponds to a reduced inflammatory response by the inhibition of adhesion and migration of immune cells. As all of the observed effects are potentially mediated via Toll-like receptor 4 (TLR4) signaling, TLR4 transfected HEK293 cells were incubated with OS1. LPS-induced IL-8 secretion was significantly inhibited in a concentration-dependent manner, confirming TLR4 antagonism. This inhibition, however, was in part caused by an interaction of OS1 with LPS. In addition, also an aqueous extract containing high amounts of isoflavonoid glycosides and saponins from the roots of O. spinosa showed anti-inflammatory effects by interacting with the TLR4 signaling pathway. This study rationalizes the traditional use of extracts from O. spinosa for therapy of urinary tract infections, due to its potential anti-inflammatory effects that are mediated via TLR4 receptor antagonism.

root extract

Human hyaluronidase-1 (Hyal-1) is one of the main enzymes in the homeostasis of hyaluronic acid (HA), the main polysaccharide of extracellular matrix. Development of specific Hyal-1 inhibitors might be a promising target for improved wound healing, tissue regeneration, and looking at renal function for diuresis. By using surface-displayed Hyal-1 on Escherichia coli F470 cells, HA as substrate and stains-all method for quantification of undegraded HA, the respective enzyme activity can be determined easily. Based on the traditional use of extracts from the roots from Ononis spinosa L. (Restharrow root) as a weak diuretic to achieve flushing of the urinary tract and as an adjuvant in minor urinary complaints the herbal material was selected for bioactivity guided fractionation for compounds with Hyal-1 inhibition activity. Hot water and hydroalcoholic extracts showed moderate inhibiting effects (IC₅₀ 1.36 resp. 0.73 mg/mL) while dichloromethane extract exerted an IC₅₀ of 190 μg/mL. Bioassay guided fractionation of the dichloromethane extract yielded four isoflavonoids with anti Hyal-1 activity: onogenin 1, sativanone 2, medicarpin 3 and calycosin-D 4 with inhibition rates of 25.4, 61.2, 22.4 and 23.0%, respectively at test concentration level of 250 μM. The norneolignan clitorienolactone B 5, the first time described for the genus Ononis, was inactive. The IC₅₀ of sativanone, the most active compound was determined with 1501 μM, which was better than that of the positive control glycyrrhizinic acid (177 μM). Thus, a possible explanation for diuretic properties of Ononis spinosa L. root extract may be postulated from the results so far obtained.

Isoflavonoids as wound healing agents from Ononidis Radix

ETHNOPHARMACOLOGICAL RELEVANCE

Dried roots of Ononis spinosa L. are traditionally used for their diuretic, anti-inflammatory and wound healing effects.

AIM OF THE STUDY

Isolation of the bioactive compounds of Ononis spinosa L. subsp. leiosperma (Boiss.) Sirj.

MATERIALS AND METHODS

Ethyl acetate extract prepared from the roots of Ononis spinosa L. subsp. leiosperma (Boiss.) Sirj. was subjected to silica gel column. The fractions were tested for their wound healing and anti-inflammatory activities. Linear incision and circular excision wound models and hydroxypyroline estimation assay were used for the wound healing activity. Carrageenan-induced hind paw edema, TPA-induced ear edema and acetic acid-induced increase in capillary permeability tests as acute inflammation; FCA-induced arthritis as chronic inflammation models were used for the assessment of anti-inflammatory activity. Antioxidant capacities of the fractions were tested using 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay, 2,2-azino-bis-(3-ethylbenzthiazoline-6-sulfonic acid (ABTS) scavenging activity assay, reducing power assay and hydroxyl radical (OH^-) scavenging assay. The isolation procedure was continued with the active fraction (Fr-E5).

RESULTS

Fr-E5 exhibited remarkable wound healing activity with the 33.4% tensile strength value on the linear incision wound model and 51.4% reduction of the wound area at the day 12 on the circular excision wound model. Hydroxyproline content of the tissue treated by Fr-E5 was found to be 30.9 ± 0.72μg/mg. Acetic acid induced increase in capillary permeability test results revealed that Fr-E5 inhibited inflammation by the value of 40.3%. Fr-E5 showed 28.1-32.2% inhibition in carrageenan-induced hind paw edema test while did not possess activity on TPA-induced ear edema and FCA-induced arthritis models. Trifolirhizin, ononin, medicarpin-3-O-glucoside, onogenin-7-O-glucoside and sativanone-7-O-glucoside were isolated from Fr-E5 and tested for their wound healing activities using by measuring their inhibition of hyaluronidase, collagenase and elastase enzymes. Ononin and sativanone-7-O-glucoside inhibited hyaluronidase and elastase enzymes by 31.66% and 41.75%; 45.58% and 46.88% values respectively at the dose of 100μg/mL.

CONCLUSION

Among five isolated compounds, ononin and sativanone-7-O-glucoside were found to inhibit hyaluronidase and elastase enzymes. According to the results, these compounds may majorly be responsible for the wound healing activity of the extract.