Wissem MNIF | King Khalid University (original) (raw)

Papers by Wissem MNIF

Background: Lipid transfer proteins (LTP) are members of the family of pathogenesis-related prote... more Background: Lipid transfer proteins (LTP) are members of the family of pathogenesis-related proteins (PR-14) that play a key role in plant defense mechanisms. Methods: In this study, a novel gene TdLTP4 encoding an antifungal protein from wheat (cv. Om Rabiaa) was subcloned, overexpressed in Escherichia coli BL-21 (DE3) and enriched using ammonium sulfate fractionation. The TdLTP4 fusion protein was then tested against a panel of pathogens, food-borne and spoilage bacteria and fungi in order to evaluate the antimicrobial properties. Our protein was applied to 0.5 µg/mL LPS-induced RAW 264.7 macrophages in vitro at different concentrations (5, 10, 20, 50 and 100 µg/ml). Levels of nitric oxide (NO), pro-in ammatory cytokines interleukin (IL)-1β (IL-1 β), interleukin (IL)-6 (IL-6), tumor necrosis factor (TNF-α) and anti-in ammatory cytokine IL-10 in the supernatant fraction were measured using enzyme-linked immunosorbent assay (ELISA). Expression of cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) were detected via Western blot. Results: The inhibition zones and minimal inhibitory concentration (MIC) values of bacterial strains were in the range of 14-26 mm and 62.5-250 µg/mL, respectively. Moreover, a remarkable activity against several fungal strains was revealed. TdLTP4 (5-100 µg/mL) decreased the production of NO (IC 50 = 4.32 µg/mL), IL-6 (IC 50 = 11.52 µg/mL), IL-1β (IC 50 = 7.87 µg/mL) and TNF-α (IC 50 =8.66 µg/mL) by lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophages. Our protein could modulate the macrophages in ammatory mode by causing reduction in iNOS and COX 2. Conclusion: According to these ndings, LTP fusion protein could be used as natural anti-in ammatory and antimicrobial agent in food preservation and human health.

Foods, Dec 6, 2022

This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY

Resumen del trabajo presentado al XVIII Scientific Meeting of the Spanish Society of Chromatograp... more Resumen del trabajo presentado al XVIII Scientific Meeting of the Spanish Society of Chromatography and Related Techniques (SECyTA), celebrado en Granada del 2 al 4 de octubre de 2018.

International Journal of Molecular Sciences, Feb 3, 2023

International Journal of Pharmacy and Pharmaceutical Sciences, 2015

Objective: This study was conceived to evaluate the essential fatty acids, secondary metabolite, ... more Objective: This study was conceived to evaluate the essential fatty acids, secondary metabolite, antimicrobial and antioxidant activities of Olea europaea ssp. oleaster fruits pulp methanolic extract. Methods: Analysis of the lipid content from unexploited Olea europaea ssp. oleaster pulp was carried out using gas chromatography. The antioxidant activity was evaluated by DPPH radical scavenging. The antimicrobial activity was also tested against seven pathogenic bacteria, two fungal species and one yeast strain using two methods. Results: The obtained results showed that the major components of fatty acids were oleic acid (77.4%) and elaidic acid (17.58%). Moreover, the tested extract was rich in phenol (84.04±0.01 mg GAE/g DW) than in flavonoids (60.41±0.02 mg RE/g DW). In addition, it showed puissant antioxidant (IC50 = 28±0.01 µg/mL), antibacterial and antifungal activities. The inhibition zones diameters and the minimum inhibition concentration values for tested microorganisms were in the range of 13-18 mm and 3.125-25 mg/mL, respectively. Conclusion: This study shows that Olea europaea ssp. oleaster fruit pulp could be developed into ingredients for use in foods as the natural antioxidant and antimicrobial agent.

Journal of Essential Oil Bearing Plants, 2012

ABSTRACT Pistacia terebinthus seeds were submitted to hydrodistillation in a Clevenger apparatus.... more ABSTRACT Pistacia terebinthus seeds were submitted to hydrodistillation in a Clevenger apparatus. Their essential oil composition was analysed by gas chromatography coupled to mass spectrometry (GC-MS). We tested also its biological activity against some microorganisms : Escherichia Coli ATCC 25922, Staphylococcus aureus ATCC 29213 and Bacillus cereus ATCC 11778. Results showed that the most abundant volatile compound of P. terebinthus seed essential oil was β-pinene with a percentage of 38.28 %. Furthermore, monoterpene hydrocarbons accounting for 84.66 % of total volatiles constituted the prominent chemical class of this volatile oil. Respective amounts of oxygenated monoterpenes and sesquiterpenes were of 6.58 and 3.29 %. Moreover, the antibacterial assay showed that P. terebinthus seed essential oil was moderately active against the tested microorganisms due to its low amount of oxygenated monoterpenes.

Natural Product Research, Dec 12, 2012

The temperature and the speed of drying may affect the quality of the end product of medicinal pl... more The temperature and the speed of drying may affect the quality of the end product of medicinal plants. In addition, ecotypes and chemotypes could be factors influencing this quality. Thus, the aim of our study was to explore various techniques of drying of Origanum syriacum L., which is considered as a main ingredient in the Lebanese diet. For all these reasons, we decided to study two types of O. syriacum originating from Rkai and Ibrine regions on which analyses were carried out. In view of our results, a moderate temperature, in the absence of light, is more favourable for the safeguarding of the flavours and chlorophylls. On the other hand, these conditions seem to be unsuitable for other substances. In order to clarify the optimal conditions for drying of O. syriacum to lead to a product of quality, the choice of a technique of suitable dehydration seems to be delicate.

Food Science and Nutrition, Apr 4, 2022

The aim of the present study was to investigate the extraction and the characterization of a nove... more The aim of the present study was to investigate the extraction and the characterization of a novel heteropolysaccharide from Tunisian halophyte Lobularia maritima (LmPS). We were also interested in its antioxidant, anti‐inflammatory, and hepatoprotective effects on carbon tetrachloride (CCl4)‐induced liver injury in rats. LmPS physicochemical properties were evaluated by thin‐layer chromatography (TLC), high‐performance liquid chromatography (HPLC), thermogravimetric analysis (TGA), and UV absorption. According to TLC and HPLC results, LmPS was a heteropolysaccharide composed of glucose, galactose, and xylose. Its molecular weight was 130.62 kDa. This heteropolysaccharide was characterized by a significant antioxidant potential and was efficient against oxidative stress and CCL4‐induced hepatotoxicity in rat Wistar models (n = 8) treated with a single dose of LmPS 250 mg/kg of body weight. This was evidenced by a significant increase in serum marker enzymes specially aspartate transaminase (AST), alanine transaminase (ALT), alkaline phosphatase (ALP), and lactate dehydrogenase (LDH). The cytokines released after stimulation of rats with LmPS showed high anti‐inflammatory profiles with an increased rate of interleukine‐10 (IL‐10) with 0.03 pg/mL compared to animals treated only with CCl4. On the contrary, we noticed a decrease of the other cytokines (tumor necrosis factor α: TNF‐α, interleukine‐6: IL‐6, transforming growth factor beta 1: TGF‐β1) with average concentration values of <0.2, 0.1, and 0.04 pg/mL, respectively. Besides, histopathological examinations revealed that CCl4 causes acute liver damage, characterized by extensive hepatocellular necrosis, vacuolization, and inflammatory cell infiltration, as well as DNA fragmentation. LmPS administration at a dose of 250 mg/kg resulted in a significant hepatoprotection, evidenced by a reduction of CCl4‐induced oxidative damage for all tested markers. These findings eagerly confirmed that LmPS was effective in the protection against CCl4‐induced hepatotoxicity and genotoxicity. It, therefore, suggested a potential therapeutic use of this polysaccharide as an alternative medicine for patients with acute liver diseases.

RSC Advances, 2019

Myrtus communis L. (Myrtle) is one of the most important aromatic and medicinal species from the ... more Myrtus communis L. (Myrtle) is one of the most important aromatic and medicinal species from the Myrtaceae family. It is traditionally used as antiseptic, disinfectant drug and hypoglycemic agent. The aim of our study was to evaluate the protective effect of Myrtus communis essential oil (McEO) on CCl 4-induced hepatotoxicity in rat. Thirty two adult Wistar rats were divided into 4 groups of 8 each: (1) a control group; (2) was given a single dose of CCl 4 (1 mL kg À1 in 1% olive oil. ip) on the 14 th day (3) were given during 15 days a daily i.p. injection of McEO at 250 mL kg À1 b.w (4) a group was pretreated with McEO and intoxicated with CCl 4 on the 14 th day. The major components of McEO are a-pinene (35.20%), 1,8-cineole (17%), linalool (6.17%) and limonene (8.94%) which accounted for 67.31% of the whole oil. The antioxidant activity of McEO was evaluated using DPPH scavenging ability, b-carotene bleaching inhibition and hydroxyl radical-scavenging activity. Moreover, the effect of McEO (250 mg kg À1 body weight BW) administrated for 14 consecutive days was evaluated in wistar rat. Administration of a single dose of CCl 4 caused hepatotoxicity as monitored by an increase in lipid peroxidation (thiobarbituric acid reactive substances) as well in protein carbonyl level but decreased in antioxidant markers in the liver tissue. The McEO pre-treatment significantly prevented the increased plasma levels of hepatic markers and lipid levels induced by CCl 4 in rats. Furthermore, this fraction improved biochemical and histological parameters as compared to CCl 4-treated group. Our results suggest that M. communis contains promising substances to counteract the CCl 4 intoxication and which may be efficient in the prevention of hepatotoxicity complications.

Microbial Pathogenesis, May 1, 2021

Lipid transfer proteins (LTP) are members of the family of pathogenesis-related proteins (PR-14) ... more Lipid transfer proteins (LTP) are members of the family of pathogenesis-related proteins (PR-14) that play a key role in plant defense mechanisms. In this study, a novel gene TdLTP4 encoding an antifungal protein from wheat (cv. Om Rabiaa) was cloned, overexpressed in Escherichia coli BL-21 (DE3) and enriched using ammonium sulfate fractionation. The TdLTP4 fusion protein was then tested against a panel of pathogens, food-borne and spoilage bacteria and fungi in order to evaluate the antimicrobial properties. TdLTP4 was applied to 0.5 μg/mL LPS-induced RAW 264.7 macrophages in vitro at different concentrations (5, 10, 20, 50 and 100 μg/ml). Levels of nitric oxide (NO), pro-inflammatory cytokines interleukin (IL)-1β (IL-1 β), interleukin (IL)-6 (IL-6), tumor necrosis factor (TNF-α) and anti-inflammatory cytokine IL-10 in the supernatant fraction were measured using enzyme-linked immunosorbent assay (ELISA). Expression of cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) were detected via Western blot. The inhibition zones and minimal inhibitory concentration (MIC) values of bacterial strains were in the range of 14-26 mm and 62.5-250 μg/mL, respectively. Moreover, a remarkable activity against several fungal strains was revealed. TdLTP4 (5-100 μg/mL) decreased the production of NO (IC50 = 4.32 μg/mL), IL-6 (IC50 = 11.52 μg/mL), IL-1β (IC50 = 7.87 μg/mL) and TNF-α (IC50 = 8.66 μg/mL) by lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophages. TdLTP4 could modulate the macrophages inflammatory mode by causing reduction in iNOS and COX-2. According to these findings, TdLTP4 fusion protein could be used as natural anti-inflammatory and antimicrobial agent in food preservation and human health.

Water

Due its high water content, sewage sludge dewatering is not just a simple operation; rather, it i... more Due its high water content, sewage sludge dewatering is not just a simple operation; rather, it is a challenging process and a costly management task. Its final handling is usually preceded by several dewatering steps, and among them is the conditioning process known as the flocculation stage, which is carried out using synthetic chemical reagents. Despite the abilities of these additives to reduce sludge volume and extract its bound waters, they are suspected to cause serious environmental and health threats. Their substitution by natural and efficient additives originating from plant extracts could thus be a safe and an eco-friendly alternative, overcoming ecosystem damages. It is within this context that the present review paper critically investigates the efficacy and feasibility of plant-based flocculants, aiming to enhance sludge dewatering and dispense with environmental burdens. To do so, the types of the conventional chemical flocculants, their drawbacks, and their impacts ...

Antioxidants

Citrus fruits occupy an important position in the context of the fruit trade, considering that bo... more Citrus fruits occupy an important position in the context of the fruit trade, considering that both fresh fruits and processed products are produced on a large scale. Citrus fruits are recognized as an essential component of the human diet, thanks to their high content of beneficial nutrients such as vitamins, minerals, terpenes, flavonoids, coumarins and dietary fibers. Among these, a wide range of positive biological activities are attributed to terpenes and flavonoids derivatives. In this review, a list of bibliographic reports (from 2015 onwards) on the phytochemical composition, beneficial effects and potential applications of citrus fruits and their by-products is systematically summarized. In detail, information regarding the nutraceutical and medicinal value closely linked to the presence of numerous bioactive metabolites and their growing use in the food industry and food packaging, also considering any technological strategies such as encapsulation to guarantee their stabi...

Processes

In this study, pomegranate peel extract was used to dye cotton fabrics. Generally, natural dyes h... more In this study, pomegranate peel extract was used to dye cotton fabrics. Generally, natural dyes have low affinity for cellulosic fibers and therefore need treatment for attachment. Air atmospheric plasma was applied to lower the concentrations of mordants needed and enhance dyeability. The outcomes showed that the residual concentrations of metallic ions decreased when applying the plasma treatment. ATR-FTIR and SEM analysis were performed to evaluate the effect of plasma modification on the surface chemistry and topography of the cellulosic fibers. The traces of metals released from finished fabric were quantified using ICP OES spectrometry. Color fastnesses (wash, rubbing and light) were evaluated to assess the mordanting step effect and the durability of the color. All tested fastnesses were good to very good. The concentrations of metal ions in finished fabrics were 32.4 for Fe, 0.28 for Al, 0.29 for Cr and 1.21 for Cu. Plasma treatment can be considered an efficient strategy to...

Scientific Reports, 2022

Leukemic cells proliferate faster than non-transformed counterparts. This requires them to change... more Leukemic cells proliferate faster than non-transformed counterparts. This requires them to change their metabolism to adapt to their high growth. This change can stress cells and facilitate recognition by immune cells such as cytotoxic lymphocytes, which express the activating receptor Natural Killer G2-D (NKG2D). The tumor suppressor gene p53 regulates cell metabolism, but its role in the expression of metabolism-induced ligands, and subsequent recognition by cytotoxic lymphocytes, is unknown. We show here that dichloroacetate (DCA), which induces oxidative phosphorylation (OXPHOS) in tumor cells, induces the expression of such ligands, e.g. MICA/B, ULBP1 and ICAM-I, by a wtp53-dependent mechanism. Mutant or null p53 have the opposite effect. Conversely, DCA sensitizes only wtp53-expressing cells to cytotoxic lymphocytes, i.e. cytotoxic T lymphocytes and NK cells. In xenograft in vivo models, DCA slows down the growth of tumors with low proliferation. Treatment with DCA, monoclonal...

Resumen del trabajo presentado a las III Jornadas Científicas CIAL Fórum, celebradas del 22 al 23... more Resumen del trabajo presentado a las III Jornadas Científicas CIAL Fórum, celebradas del 22 al 23 de noviembre de 2018 en el Instituto de Investigación en Ciencias de la Alimentación (CIAL).The date palm Phoenix dactylifera, a tropical and subtropical tree, belonging to the family Palmae (Arecaceae) is one of mankind’s oldest cultivated plants. Date palm has long been one of the most important fruit crops in the arid regions of the Arabian Peninsula, North Africa, and the Middle East. Dates are a major food source and income source for local populations in the Middle East and North Africa, and play significant roles in the economy, society, and environment in these areas. Date fruits have gained great importance in human nutrition owing to their rich content of essential nutrients and various biological activities (hepatoprotective, anti-genotoxic, nephroprotective, anti-allergic, neuroprotective, antiviral, antifungal. The aim of this work is to figure out set up a sample preparation method to address the composition and to explore the different activities of dates (fruit and seed) by using “green” extractions methods and to assess the differences between the varieties coming from different localities. From the seeds, oil has been extracted by a supercritical CO2 and analyzed by GC-MS. To set up the extraction conditions to have the best extract, a chemometric optimization was done. Different ranges of pressure (100-300 bar), temperature (40-80°C) and co-solvent (Ethanol: 0-10%) were chosen, then a statistical analysis was done to determine the optimum conditions (100 bar, 40°C and 10% ethanol). The oil of each extract obtained was analyzed by gas chromatography to determine the profile in fatty acids. The main fatty acid found in all the varieties was myristic acid (C14:0). In order to determine the lipid class composition of the oil, the extracts had been analyzed by HPLC-ELSD. From the pulp the extraction was operated by Pressurized liquid extraction (PLE). The same methodology of optimization has been used; the variables were temperature (50-150°C) and solvent composition (Ethanol 100%, water 100%, water/Ethanol 50%). To get the optimum conditions an antioxidant assay was run and the yield was evaluated and then analyzed by the same method as SFE. The optimum was determined at those conditions of temperature: 150°C and Ethanol: 72%. Then the plenolic composition of extracts were analyzed by HPLC-DAD-MS/MS for quantification purposes.This work was done thanks to the support and financial help of the Tunisian Ministry of High Education and Scientific Research via the University of Carthage and the Faculty of Science of Bizerte.Peer reviewe

Materials Research Express, 2019

Cactus is cultivated in many regions over the world. Because of its chemical composition and its ... more Cactus is cultivated in many regions over the world. Because of its chemical composition and its valuable nutritional and biological characteristics, cactus finds applications in different sectors such as the pharmaceutical and the food industries. Interestingly, cactus materials (cladodes, fruit seeds, peel, etc) have been explored for their probable use as adsorbents for the removal of toxic heavy metals and dyes from wastewater. Various preparations methods were used to produce cactus material-based biosorbents. These biosrbents have been investigated and successfully used for the elimination of both heavy metal and dyes from aqueous solutions. Related results showed very promising pollutant removal efficiency associated with an interesting adsorption capacity similar to other materials from various origins. This paper explores various cactus biosorbents preparations. Furthermore, their efficiency in depollution and factors controlling the adsorption capacity will be discussed.

Journal of Developing Drugs, 2015

It has been reported that dyes toxicity may happen due to either the direct action of the origina... more It has been reported that dyes toxicity may happen due to either the direct action of the original compound or its intermediate metabolites such as naphthalene, benzidine and other aromatic amines

Journal of Essential Oil Bearing Plants, 2016

Abstract: Albizia julibrissin seed oil was extracted by the continuous method of soxhlet. We were... more Abstract: Albizia julibrissin seed oil was extracted by the continuous method of soxhlet. We were interested to some physicochemical parameters of the oil. The main results showed that the saponification number was of 190; the iodine value was of 111 whereas the acid value was equal to 2.54. Concerning oil composition, the main fatty acids (FA) were linoleic (57.7 %), palmitic (12.5 %) and oleic ones (9.8 %). The major triacylglycerols (TAGs) were represented by ECN 42 accounting for 56.2 % of TAGs. Concerning ECN 44, it was represented by OLL. Furthermore, PLL accounted for 39 %. It is worth mentioning that A. julibrissin oil was rich in β-carotene and that it was characterized by a low quantity of chlorophylls according to its UV spectrum in the region 400-800 nm. Concerning the UV spectra in the region 200-400nm, our profile revealed an important absorbency in the domain UV-C and low absorbencies in the domains UV-B and UV-A. These findings showed that A. julibrissin seed oil could be valorised in many sectors such as cosmetic, pharmaceutical and agro industry.