ANTI-INFLAMMATORY, ANALGESIC AND ANTIOXIDANT ACTIVITIES OF HYDRO-ACETONIC EXTRACT FROM WISSADULA AMPLISSIMA VAR. ROSTRATA (SHUM. AND THONN.) R. E. FRIES

Objective: The present study aims to investigate anti-inflammatory, analgesic and antioxidant effects of the hydroacetonic extract (HAE) from Wissadula amplissima whole plant and to determine its polyphenol and flavonoid contents.Methods: Extraction was achieved by soaking defatted W. amplissima with aqueous acetone solvent. Acute toxicity and pharmacological investigations were performed per os and intraperitoneally on Naval Medical Research Institute (NMRI) mice. The carrageenan-induced paw edema and the acetic acid-induced writhing tests were used to assess the in vivo anti-inflammatory and analgesic activities. Inhibition of xanthine oxidase and lipoxygenase were carried out in vitro using endpoint spectrophotometric assays at 295 nm and 234 nm. 2,2-diphenyl-1-picrylhydrazyl (DPPH), Ferric Reducing Antioxidant Power (FRAP), lipid peroxidation and desoxyribose degradation assays were used to point out antioxidant activities of extract. Aluminium chloride colorimetric method was used to determine total flavonoids content when and total phenolic content was measured by the method Folin-ciocalteu reagent.Results: W. amplissima's HAE exhibited a slight acute toxicity with no lethality observed. Significant (p<0.05) anti-inflammatory and analgesic activities were recorded as well as strong inhibitory activities on lipoxygenase and xanthine oxidase. W. amplissima's HAE also demonstrated interesting antioxidant activities particularly in preventing lipid peroxidation. Polyphenol and flavonoid contents were respectively estimated to 64.33±1.34 mg Gallic Acid Equivalent (GAE) and 35.17±0.77 mg Quercetin Equivalent (QE) per 100 mg of W. amplissima's HAE.Conclusion: HAE of W. amplissima exhibited a promising anti-inflammatory and analgesic potential compared to the reference (acetylsalicylic acid, Hydrocortisone, paracetamol) and regarding the inhibition of lipoxygenase and lipid peroxidation. The anti-inflammatory and analgesic activities seem to be related to the antioxidant and enzymes inhibitors compounds of the plant extract.Â

Comparative Study of Two Monoterpenes Effect on Rhipicephalus microplus Tick

The cattle tick Rhipicephalus microplus is one of the most important ectoparasites for livestock in tropical and subtropical areas worldwide. This tick hurts the economy of the milk and meat production chain. In addition, it constitutes a vector for the transmission of Anaplasmosis and Babesiosis pathogens. The control of R. microplus populations is mainly based on the use of synthetic acaricides. However, using this control method presents a danger to humans and the environment and leads to the emergence of resistant tick populations. In this situation, searching for ecological and effective control alternatives is essential. Thus, plant extracts constitute a promising solution, particularly essential oils and their active compounds. Thus, the present study aims to assess the acaricidal activity of two monoterpenes (Thymol and 1.8 cineole) abundantly found in essential oils to find an alternative to synthetic acaricides. The acaricidal activity was determined according to the method of larval immersion test (LIT). Eight concentrations were tested and R software version 4.0.3 was used for data analysis. Results showed 100 % larval mortality rates for the two monoterpenes with LC50 and LC90 values of (0.28 and 0.64) and (0.64 and 2.66) respectively, for thymol and 1.8 cineole for the immersion time of 5 min. For 10 min of immersion, all LC values decreased for the two monoterpenes. These findings highlight the potential of the thymol and 1.8 cineole as an alternative for managing R. microplus tick

ANTI-INFLAMMATORY ACTIVITIES OF FRUIT AND LEAVES EXTRACT OF LANNEA MICROCARPA ENGLAND K. KRAUS (ANACARDIACEAE)

Objective:  To investigate the anti-inflammatory activity as well as carotenoid content of crude hydro-acetonic extract of fruit and leaves of Lannea microcarpa (L. microcarpa) and to elucidate the possible anti-inflammatory mechanism by enzymatic and non-enzymatic methods.Methods:  Anti-inflammatory activity was determined by using carrageenan induced paw edema in mice;  the anti-inflammatory mechanism may have been assessed using the inhibitory effect of the extracts, on the lipoxygenase, xanthine oxidase, lipid peroxidation and the reduction of Fe3+.Results:  At the doses of 100mg/kg, 200mg/kg, 400mg/kg, the extracts of both fruit and leaves reduced the carrageenan-induced paw edema while the dose of 200 mg/kg has produced a maximum percentage of inhibition of mice paw edema both for fruit (78.44%) and leaves (58.02%) at the fifth hour compared to control. Significant lipoxigenase and xanthine oxidase inhibitory effect was obtained with both fruit and leaves extract ethyl acetate fraction. Ethyl acetate fraction from both extracts inhibited lipid peroxidation. The fruit and leaves extract ethyl acetate fraction also inhibited lipid peroxidation with 32.85% and 78.07% respectively. Crude acetonic extract of leaves of Lannea microcarpa has shown a significantly reducing power of Fe3+ by 9.46±0.26 and high carotenoids content compared to those of fruit extract.Conclusion: The results obtained from the present study suggest that Lannea microcarpa fruit and leaves extract possess significant anti-inflammatory and antioxidant capacities (mg AAE/100 mg). Therefore, they could be useful for food and pharmaceutics industries.Â

Phenolic composition, in vitro antioxidant effects and tyrosinase inhibitory activity of three Algerian Mentha species: M. spicata (L.), M. pulegium (L.) and M. rotundifolia (L.) Huds (Lamiaceae)

International audienceThe leaves of three Mentha species harvested in Algeria, Mentha spicata L. (MS), Mentha pulegium L. (MP) and Mentha rotundifolia (L.) Huds (MR) were examined for their content in polyphenols and for some activities-linked biological properties these could impart. The contents in total phenolics (TPC) and flavonoids (TFC) were evaluated by the Folin–Ciocalteu and the aluminum chloride methods, respectively. Whereas MS showed the highest TPC (12.0 ± 0.3 mg gallic acid equivalents/g of dry weight), MR had the highest content in TFC (3.3 ± 0.1 mg quercetin equivalents of dry weight). The pharmacological properties of these extracts were evaluated by assessing in vitro their antioxidant and antityrosinase activities. The modulation of mushroom tyrosinase activity was measured by colorimetry of the melanins formed in the presence of tyrosine. MS exhibited the strongest radical scavenging activity (RSA) in all assays: (i) the IC50s values to neutralize the 2,2′-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) cation radicals (ABTS+) and the 2,2′-diphenyl-1-picrylhydrazyl radicals (DPPH) were 10.3 ± 0.9 and 16.2 ± 0.2 μg/mL, respectively; and (ii) its original electrochemically measured superoxide quenching index value is 188 ± 37 μg/mL (AI50). MR however showed the highest tyrosinase inhibitory activity (IC50 = 108 ± 20 μg/mL). A silica gel thin-layer chromatography (TLC) technique revealed the presence of caffeic and rosmarinic acids and diosmin in all extracts. These results were confirmed by high performance liquid chromatography with diode array detection (HPLC/DAD

Phenolic compounds, antioxidant and antibacterial activities of three Ericaceae from Algeria

International audienceHerbs of the Ericaceae family are commonly found in Algeria and used in traditional medicine as antiseptic, diuretic, astringent, depurative, and to treat scalds and wounds. The methanolic extracts of three species, Arbutus unedo L. (A. unedo, leaves), Erica arborea L. (E. arborea, flowered aerial parts), and Erica multiflora L. (E. multiflora, flowered aerial parts), were compared regarding their content in phenolic compounds, their antioxidant, and antibacterial activities. A. unedo harbors the highest content in total phenolics and flavonoids, followed by E. arboreaE. multiflora. The contents in total phenolics and flavonoids showed a correlation with the measured antioxidant (hydrogen-donating) activities; this was particularly the case for flavonoids content. The A. unedo extract showed antibacterial activity against all the tested strains (Staphylococcus aureus ATCC 6538, S. aureus C100459, Escherichia coli ATCC 25922, and Pseudomonas aeruginosa ATCC 9027); however, the E. arborea and E. multiflora extracts showed antibacterial activity only against Gram positive bacteria. Some polyphenols were identified in the three herbs by thin-layer chromatography and high-performance liquid chromatography coupled with diode array and mass spectrometry detection; from these, caffeic acid, p-coumaric acid, naringin, quercetin and kaempferol are reported for the first time in E. multiflora

Antibacterial and anti-inflammatory activities of crude extracts of three Togolese medicinal plants against ESBL Klebsiella pneumoniae strains

Background: Pithecellobium dulce (Roxb.) Benth., Securidaca longepedunculata Fresn and Cryptolepis sanguinolenta (Lindl.) Schlt are three plants widely used in the Togolese traditional medicine to treat microbial infections. Some studies reported their antibacterial activity alone but until know there no data concerning their possible interaction with conventional antibiotics. The main objective of this study was to investigate the antibacterial activity of the association of the crude extracts of the three plants with some conventional antibiotics. We further evaluate the antioxidant and the anti-inflammatory activities of the extracts on rat’s model.Materials and methods:The antimicrobial activity was evaluated by the broth microdilution assay and the Fractional inhibitory concentrations (FIC) determined by the checkerboard method. The anti-inflammatory activity was evaluated using the Carrageenan- induced rat paw edema model. The antioxidant activities and the phenol contents were determined by spectrophotometry.Results: The MICs of hydroethanolic extract of plants ranged from 3.125 to 100 mg/mL on Klebsiella pneumoniae strains. Synergistic action was observed only with the combination of Imipenem/P. dulce, imipenem/C. sanguinolenta, amikacin/P. dulce and amikacin/C. sanguinolenta against the ESBL negative Klebsiella pneumoniae strain. Of the 21 associations, 15 were antagonistic on the ESBL-producing strains. The indifference effect was observed with the combination of the extract of Securidaca longepedunculata and the following antibiotics imipenem, amikacin, tetracyclin, ciprofloxacin, Cefotaxim; and Sulfametoxazol+Trimethoprim. The in vitro anti-inflammatory with Lipoxygenase inhibition activity was best with C. sanguinolenta extract while the in vivo paw edema model revealed that S. longepedunculata was the highest reducer of paw edema. In addition white blood cells count and biochemical parameters such as total proteins and immunoglobulins were significantly affected by the administration of plant extracts.Conclusion: This study revealed that the three plants although they may inhibit the bacterial growth by themselves, but there is also a possible synergistic action with the commercial antibiotics. Further investigations are needed to identify the active compounds and their mechanism of action.Keywords: antibiotics, extended-spectrum beta lactamase, plant extract, bacteria, Tog

ANTIBACTERIAL AND ANTI-INFLAMMATORY ACTIVITIES OF CRUDE EXTRACTS OF THREE TOGOLESE MEDICINAL PLANTS AGAINST ESBL KLEBSIELLA PNEUMONIAE STRAINS

Background: Pithecellobium dulce (Roxb.) Benth., Securidaca longepedunculata Fresn and Cryptolepis sanguinolenta (Lindl.) Schlt are three plants widely used in the Togolese traditional medicine to treat microbial infections. Some studies reported their antibacterial activity alone but until know there no data concerning their possible interaction with conventional antibiotics. The main objective of this study was to investigate the antibacterial activity of the association of the crude extracts of the three plants with some conventional antibiotics. We further evaluate the antioxidant and the anti-inflammatory activities of the extracts on rat’s model. Materials and methods:The antimicrobial activity was evaluated by the broth microdilution assay and the Fractional inhibitory concentrations (FIC) determined by the checkerboard method. The anti-inflammatory activity was evaluated using the Carrageenan- induced rat paw edema model. The antioxidant activities and the phenol contents were determined by spectrophotometry. Results: The MICs of hydroethanolic extract of plants ranged from 3.125 to 100 mg/mL on Klebsiella pneumoniae strains. Synergistic action was observed only with the combination of Imipenem/P. dulce, imipenem/C. sanguinolenta, amikacin/P. dulce and amikacin/C. sanguinolenta against the ESBL negative Klebsiella pneumoniae strain. Of the 21 associations, 15 were antagonistic on the ESBL-producing strains. The indifference effect was observed with the combination of the extract of Securidaca longepedunculata and the following antibiotics imipenem, amikacin, tetracyclin, ciprofloxacin, Cefotaxim; and Sulfametoxazol+Trimethoprim. The in vitro anti-inflammatory with Lipoxygenase inhibition activity was best with C. sanguinolenta extract while the in vivo paw edema model revealed that S. longepedunculata was the highest reducer of paw edema. In addition white blood cells count and biochemical parameters such as total proteins and immunoglobulins were significantly affected by the administration of plant extracts. Conclusion: This study revealed that the three plants although they may inhibit the bacterial growth by themselves, but there is also a possible synergistic action with the commercial antibiotics. Further investigations are needed to identify the active compounds and their mechanism of action

Ultralight vector dark matter search using data from the KAGRA O3GK run

Among the various candidates for dark matter (DM), ultralight vector DM can be probed by laser interferometric gravitational wave detectors through the measurement of oscillating length changes in the arm cavities. In this context, KAGRA has a unique feature due to differing compositions of its mirrors, enhancing the signal of vector DM in the length change in the auxiliary channels. Here we present the result of a search for U(1)B−L gauge boson DM using the KAGRA data from auxiliary length channels during the first joint observation run together with GEO600. By applying our search pipeline, which takes into account the stochastic nature of ultralight DM, upper bounds on the coupling strength between the U(1)B−L gauge boson and ordinary matter are obtained for a range of DM masses. While our constraints are less stringent than those derived from previous experiments, this study demonstrates the applicability of our method to the lower-mass vector DM search, which is made difficult in this measurement by the short observation time compared to the auto-correlation time scale of DM

Methanol Extract from Anogeissus leiocarpus (DC) Guill. et Perr. (Combretaceae) Stem Bark Quenches the Quorum Sensing of Pseudomonas aeruginosa PAO1

Background: Due to its extensive arsenal of virulence factors and inherent resistance to antibiotics, Pseudomonas aeruginosa is a threat particularly in immunocompromised patients. Considering the central role of quorum sensing in the production of virulence factors, inhibition of bacterial communication mechanism constitute an opportunity to attenuate pathogenicity of bacteria resistant to available antibiotics. Our study aimed to assess the anti-quorum sensing activity of Anogeissus leiocarpus, traditionally used in Burkina Faso, for the treatment of infected burn wounds. Methods: Investigations were carried out on methanol extract from A. leiocarpus stem bark. The reporter strains Chromobacterium violaceum CV026 and P. aeruginosa PAO1 derivatives were used to evidence any interference with the bacterial quorum sensing and expression of related genes. P. aeruginosa PAO1 was used to measure the impact on pyocyanin production. Results: At a sub-inhibitory concentration (100 µg/mL), A. leiocarpus methanol extract quenched the quorum sensing mechanism of P. aeruginosa PAO1 by down-streaming the rhlR gene, with a subsequent reduction of pyocyanin production. Moreover, the antioxidant polyphenols evidenced are able to reduce the oxidative stress induced by pyocyanin. Conclusion: The antioxidant and anti-quorum sensing activities of A. leiocarpus stem bark could justify its traditional use in the treatment of infected burn wounds