14 research outputs found
Biofilm inhibition of Inula viscosa (L.) Aiton and Globularia alypum L. extracts against Candida infectious pathogens and In vivo action on galleria mellonella model
The increasing importance of fungal infections has fueled the search for new beneficial alternatives substance from plant extracts. The current study investigates the antifungal and antibiofilm activity of Inula viscosa (L.) Aiton and Globularia alypum (L.) leaves extracts against Candida both in vitro and in vivo. The inhibition of planktonic and sessile Candida albicans and Candida glabrata growth using both leaf extracts are evaluated. Moreover; an in vivo infection model using Galleria mellonella larvae; infected and treated with the extracts are performed. All extracts show fungicidal activity; with a minimum fungicidal concentration (MFC) ranging from 128 to 512 mu g mL(-1) against the two selected strains of Candida. In particular, the best results are obtained with methanolic extract ofI. viscosa and G. alypum with an MFC value of 128 mu g mL(-1). The extracts are capable to prevent 90% of biofilm development at minor concentrations ranging from 100.71 +/- 2.49 mu g mL(-1) to 380.4 +/- 0.92 mu g mL(-1). In vivo, tests on Galleria mellonella larvae show that the extracts increase the survival of the larvae infected with Candida. The attained results reveal that I. viscosa and G. alypum extracts may be considered as new antifungal agents and biofilm inhibiting agents for the pharmaceutical and agro-food field
Exploring the potential anti-inflammatory and wound-healing proprieties of Cepaea hortensis snail mucin
Long before its popularization as a skincare ingredient, snail slime was reported to have a variety of health-promoting attributes. Its medicinal use involved the treatment of ailments, such as anthrax, hernias, stomach pain, chest pain, as well as tuberculosis. The main aim of this study was to investigate the anti-inflammatory and wound-healing properties of snail slime from Cepaea hortensis (Müller, 1774) (brown garden snail). The slime was extracted by a mild method, and the anti-inflammatory characteristics were determined by croton-oil-induced mouse-ear edema. The histological study showed that the snail slime exerts its action at the level of inflammatory mediators, explaining the drastic decrease of edema (59% in comparison to the 47% of indomethacin). The daily application of 50 µL (15 mg/kg) of snail slime on excision wounds in rabbits proved to induce an almost full tissue repair after 24 days of treatment (87.80–92.7% wound closure in width and length, respectively). Analysis of the slime’s safety aspect allowed affirming the nontoxicity of snail slime on both the skin and eyes.info:eu-repo/semantics/publishedVersio
Diagnostic centralisé et décentralisé des systèmes dynamiques hybrides : application à un convertisseur à trois cellules
Les travaux de ma thèse ont pour but la définition d’une démarche modulaire permettant le diagnostic des défauts liés conjointement aux dynamiques continue et discrète des systèmes dynamiques hybrides, en particulier les Systèmes Continus à Commande Discrète. L’objectif est de construire un modèle de diagnostic appelé, diagnostiqueur, permettant de diagnostiquer à la fois les défauts paramétriques et discrets des systèmes dynamiques hybrides de grande taille. Les défauts paramétriques sont caractérisés par un changement anormal de certains paramètres tandis que les défauts discrets sont caractérisés par un changement inattendu du mode discret du système. Cette démarche est basée sur une modélisation modulaire orientée composant permettant de tenir compte de la nature composite du système. Elle tient compte également des interactions entre les dynamiques discrètes et continue. Cette démarche est développée à travers deux approches. Une approche de diagnostique modulaire dont le diagnostiqueur est construite à partir du modèle global de système, et une approche de diagnostique décentralisé dont d’un ensemble des diagnostiqueurs locaux sont construits à partir des modèles locaux des composants système. Ces deux approches sont validées en utilisant un convertisseur à trois cellules.This thesis aims at defining a diagnosis approach for hybrid dynamic systems in particular Discretely Controlled Continuous Systems. The goal is to build a diagnosis module called, diagnoser, able to diagnose parametric and discrete faults. Parametric faults affect the system continuous dynamics and are characterized by abnormal changes in some system parameters; whereas discrete faults affect the system discrete dynamics and are considered either as the occurrence of unobservable events and/or reaching discrete fault modes. This approach is based on modular modeling in order to take into account the interactions between continuous and discrete dynamics. This approach is developed through two approaches. A modular diagnosis approach in which the diagnoser is built based on the use of the global model and a decentralized approach in which a set of local diagnosers are built based on the local model of the system components. The three-cell converter is used to demonstrate the efficacy of these two approaches
Development and Validation of a TLC-Densitometry Method for Histamine Monitoring in Fish and Fishery Products
Histamine poisoning is a significant public health problem. Therefore, the monitoring of histamine content in fish and fishery products is considered to be a crucial measure in the seafood industry. In the present study, a simple and rapid densitometric thin-layer chromatographic (TLC) method for histamine determination in fish samples was developed and validated. The samples were homogenized with 10% trichloroacetic acid and histamine was efficiently extracted. Then, an appropriate derivatization procedure was adopted with dansyl chloride. Once the derivatization was carried out, the samples were applied to silica gel TLC plates and developed by ascending chromatography with chloroform-triethylamine (6:4, v/v) as the mobile phase. The intensity of the histamine-dansyl derivative spots was measured by densitometry at 365 nm, and the quantitation was performed by BIO-1D image processing software. The validation of this method revealed good linearity and specificity over a concentration range from 6.25 to 100 mg/kg. Adequate precision was shown by relative standard deviations (RSD) smaller than 4.82%, accuracy ranged from −6.88% to 5.28%, and satisfactory recoveries ranging from 93% to 105% were obtained. The Limit of Detection and the Limit of Quantification were calculated at 4.4 mg/kg and 10.5 mg/kg, respectively. In addition, the effectiveness of the proposed method was assessed by the analysis of various samples, and the obtained results were confirmed with those achieved by the HPLC-UV method. Moreover, the developed method was found to be simple, cheap, and suitable for application to analyze several samples simultaneously