Acute toxicity and antioxydant property of Striga hermonthica (Del.) Benth (Scrophulariaceae)

Plants containing flavonoids have been reported to possess strong antioxidant properties. The aqueous acetone extract of Striga hermonthica was further separated into aqueous and ethyl acetate fractions and assayed for their in vitro antioxidant properties using 2,2-diphenyl-1-picrylhydrazyl (DPPH). Thecrude extract exhibits a weak antioxidant activity (IC50 of 95.27±2.30 ìg/ml) and an insignificant acute toxicity on mice (LD50: 1753±44 mg/kg). Luteolin was isolated and identified by mean of its spectral data as the main DPPH radical scavenger of the ethyl acetate fraction, exhibiting an IC50 value of 6.80±1.46 ìg/ml. These results suggest an antioxidant potential for S. hermonthica

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-proliferative effect of Scoparia dulcis L. against bacterial and fungal strains

Scoparia dulcis L. was sequentially extracted with hexane, chloroform and methanol and soaked with aqueous-acetone (80%) to check for its antimicrobial activities against five bacterial and four fungal strains.250μg of each extract loaded on a whatman paper disc exhibited significant antimicrobial activities on all the fungus and against Gram-negative and Gram-positive bacteria. Therefore, P. mirabilis is less sensitive to all the extracts while B. cereus, a â-lactamase producer bacterium, was resistant to the activity of the polar methanol and aqueous-acetone extracts. By the microdilution method, the most active extracts were chloroform extract on B. cereus with minimal inhibitory concentration (MIC) of 1.56 mg/ml and Aqueous-acetone extract on S. typhimurium (MIC = 1.56 mg/ml); the antifungal activity was strongest for hexane extract (MIC = 6.25 mg/ml) on both A. niger and P. roquefortii.Keywords: Scoparia dulcis, Antibacterial, Antifungal, Polyphenols

Updated observing scenarios and multi-messenger implications for the International Gravitational-wave Network's O4 and O5

Advanced LIGO and Virgo's third observing run brought another binary neutron star merger (BNS) and the first neutron-star black-hole (NSBH) mergers. While no confirmed kilonovae (KNe) was identified in conjunction with any of these events, continued improvements of analyses surrounding GW170817 allow us to project constraints on the Hubble Constant ($H_0$), the Galactic enrichment from $r$-process nucleosynthesis, and ultra-dense matter possible from forthcoming events. Here, we describe the expected constraints based on the latest expected event rates from the international gravitational-wave network (IGWN) and analyses of GW170817. We show the expected detection rate of gravitational waves and their counterparts, as well as how sensitive potential constraints are to the observed numbers of counterparts. We intend this analysis as support for the community when creating scientifically-driven electromagnetic follow-up proposals. During the next observing run O4, we predict an annual detection rate of electromagnetic counterparts from BNS of $0.43^{+0.58}_{-0.26}$ ($1.97^{+2.68}_{-1.2}$) for the Zwicky Transient Facility (Rubin Observatory)

NMMA: A nuclear-physics and multi-messenger astrophysics framework to analyze binary neutron star mergers

The multi-messenger detection of the gravitational-wave signal GW170817, the corresponding kilonova AT2017gfo and the short gamma-ray burst GRB170817A, as well as the observed afterglow has delivered a scientific breakthrough. For an accurate interpretation of all these different messengers, one requires robust theoretical models that describe the emitted gravitational-wave, the electromagnetic emission, and dense matter reliably. In addition, one needs efficient and accurate computational tools to ensure a correct cross-correlation between the models and the observational data. For this purpose, we have developed the NMMA (Nuclear-physics and Multi-Messenger Astrophysics) framework. The code allows incorporation of nuclear-physics constraints at low densities as well as X-ray and radio observations of isolated neutron stars. It also enables us to classify electromagnetic observations, e.g., to distinguish between supernovae and kilonovae. In previous works, the NMMA code has allowed us to constrain the equation of state of supranuclear dense matter, to measure the Hubble constant, and to compare dense-matter physics probed in neutron-star mergers and in heavy-ion collisions. The extension of the NMMA code presented here is the first attempt of analysing the gravitational-wave signal, the kilonovae, and the GRB afterglow simultaneously, which reduces the uncertainty of our constraints. Incorporating all available information, we estimate the radius of a 1.4 solar mass neutron star to be $R=11.98^{+0.35}_{-0.40}$ km

Ready for O4 II: GRANDMA Observations of Swift GRBs during eight-weeks of Spring 2022

We present a campaign designed to train the GRANDMA network and its infrastructure to follow up on transient alerts and detect their early afterglows. In preparation for O4 II campaign, we focused on GRB alerts as they are expected to be an electromagnetic counterpart of gravitational-wave events. Our goal was to improve our response to the alerts and start prompt observations as soon as possible to better prepare the GRANDMA network for the fourth observational run of LIGO-Virgo-Kagra (which started at the end of May 2023), and future missions such as SM. To receive, manage and send out observational plans to our partner telescopes we set up dedicated infrastructure and a rota of follow-up adcates were organized to guarantee round-the-clock assistance to our telescope teams. To ensure a great number of observations, we focused on Swift GRBs whose localization errors were generally smaller than the GRANDMA telescopes' field of view. This allowed us to bypass the transient identification process and focus on the reaction time and efficiency of the network. During 'Ready for O4 II', 11 Swift/INTEGRAL GRB triggers were selected, nine fields had been observed, and three afterglows were detected (GRB 220403B, GRB 220427A, GRB 220514A), with 17 GRANDMA telescopes and 17 amateur astronomers from the citizen science project Kilonova-Catcher. Here we highlight the GRB 220427A analysis where our long-term follow-up of the host galaxy allowed us to obtain a photometric redshift of $z=0.82\pm0.09$, its lightcurve elution, fit the decay slope of the afterglows, and study the properties of the host galaxy

The GRANDMA network in preparation for the fourth gravitational-wave observing run

GRANDMA is a world-wide collaboration with the primary scientific goal ofstudying gravitational-wave sources, discovering their electromagneticcounterparts and characterizing their emission. GRANDMA involves astronomers,astrophysicists, gravitational-wave physicists, and theorists. GRANDMA is now atruly global network of telescopes, with (so far) 30 telescopes in bothhemispheres. It incorporates a citizen science programme (Kilonova-Catcher)which constitutes an opportunity to spread the interest in time-domainastronomy. The telescope network is an heterogeneous set of already-existingobserving facilities that operate coordinated as a single observatory. Withinthe network there are wide-field imagers that can observe large areas of thesky to search for optical counterparts, narrow-field instruments that dotargeted searches within a predefined list of host-galaxy candidates, andlarger telescopes that are devoted to characterization and follow-up of theidentified counterparts. Here we present an overview of GRANDMA after the thirdobserving run of the LIGO/VIRGO gravitational-wave observatories in $2019-2020$and its ongoing preparation for the forthcoming fourth observational campaign(O4). Additionally, we review the potential of GRANDMA for the discovery andfollow-up of other types of astronomical transients.<br