Current Science International

An Integrated Spatial Assessment Framework for Evaluating Flash Flood Hazard Potential in EL-Negila Coastal Area, Marsa Matruh Governorate, Western Desert, Egypt

2026-09-03T04:03:03+00:00

The sustainable geo-environmental management of Egypt's El-Negila coastal region within the Marsa Matruh Governorate faces significant challenges, including the deterioration of natural resources driven by climate variability and flash flood occurrences. This research employs a multi-geospatial approach integrating satellite remote sensing data and GIS methodologies to map, monitor, and
evaluate these environmental changes and associated hazards. Flash flood prediction maps were generated based on multiple factors encompassing topographic, meteorological, geological, and local conditions. A 30 m resolution Digital Elevation Model (DEM). This DEM served as the basis for extracting various topographic features, including elevation, slope, watershed characteristics (drainage
density), and Topographic Wetness Index (TWI) within the GIS environment. LULC, NDVI, and road network data were derived from Sentinel-2 imagery acquired in 2025. Flash flood hazard evaluation utilized the multi-criteria Analytical Hierarchy Process (AHP) incorporating controlling parameters such as elevation, slope, watershed attributes (stream proximity and drainage density), LULC,
normalized difference vegetation index (NDVI), road network proximity, topographic wetness index (TWI), lithological composition, and precipitation patterns. The resulting hazard zonation classified the region into three risk categories high, moderate, and low representing 33.78%, 63.06%, and 3.15% of the total area, respectively. The flood hazard map indicates that the most vulnerable zones are concentrated in the northern and eastern sectors, encompassing the tourism village, El-Negila town, and Marsa Matruh city. The mitigation strategies and management recommendations proposed in this investigation offer a practical framework for sustainable development planning in the region.

Comparative Screening of Fungal Isolates for Dextranase, Glucoamylase, and Carboxymethyl Cellulase Production

2026-09-03T04:06:59+00:00

Polysaccharide-hydrolyzing enzymes are important biocatalysts in biomass conversion, food and sugar processing, fermentation, and agro-waste valorization. Soil samples collected at a depth of 20 cm from geographically separated sites in five Egyptian governorates were cultured on potato dextrose agar (PDA), and 15 fungal isolates (F1–F15) were recovered. Each isolate was screened for dextranase, glucoamylase, and carboxymethyl cellulase (CMCase) production under submerged fermentation. Reducing sugars were quantified by the dinitrosalicylic acid method. The isolates showed distinct and complementary enzyme-production profiles. F11 produced the highest dextranase-associated release (0.1156 mg/mL), F8 was the leading glucoamylase isolate (0.8528 mg/mL), and F6 showed the highest CMCase-associated release (0.1977 mg/mL). Several isolates expressed more than one detectable activity, supporting their potential use in enzyme combinations and biomass-processing applications.

Distribution, Purification and Biochemical Characterization of an Esterase from Red Palm Weevil Rhynchophorus ferrugineus (Olivier) (Coleoptera: Curculionidae) Larvae

2026-10-09T13:46:03+00:00

Red palm weevil (RPW) Rhynchophorus ferrugineus is the most destructive insect pest of numerous palm species in the world and the larval stage (grubs) is the most destructive stage. Great variation in general esterase (GE) activity is recorded among the major tissues and the fat body of the 12th instar larvae has the highest enzyme activity. A major GE isoenzyme is purified to homogeneity to a specific activity 1871.2 U/mg protein. R. ferruginous GE was biochemically characterized to estimate the compounds required for suppressing the enzyme. The enzyme has optimum activity at pH 8.0 and at a temperature of 50°C, irreversibly denatured above 60°C, is induced by Hg2+, Ni2+, Zn2+, Cu2+, Co2+, completely suppressed by Fe2+, appearing to be a Zn2+-dependent enzyme. The enzyme hydrolyzed various phosphoric esters as substrates, has high specificity towards PNPA and α-NA with Km values 0.4 and 0.8 mM. R. ferruginous GE is completely inhibited by PMSF, β-ME, DTT, and 49% by EDTA. The enzyme was inhibited competitively by PMSF and noncompetitively by β-ME and DTT with Ki values 1.5, 2.0 and 3.5 mM. The inhibition of GE can increase the susceptibility of the target pest to chemical insecticides and is appropriate for enhancing the insecticidal efficacy of the chemical insecticides. Further studies in vivo are in progress to investigate the deleterious effect of EDTA, Fe2+, and thiol reducing agent on RPW larval development and the possibility of introducing them as insecticide synergists in IPM programs for developing RPW management strategies.