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SECTION I: MOLECULAR GENETIC ENGINEERING AND BIOCHEMICAL TECHNOLOGY 79concentration of the tested sample that causes the half-maximal response, was determined by linearly regressing the serial SC values versus the concentrations. 2.4. Antimicrobial assayThis study has made use of pathogenic ATCC (American Type Culture Collection) strains, which include two Gram (+) bacteria, Bacillus subtilis ATCC 5230 and Staphylococcus aureus ATCC 33591, two Gram (%u2013) bacteria, Escherichia coli ATCC 8739 and Pseudomonas aeruginosaATCC 27853, two fungi, Aspergillus niger ATCC 9587 and Fusarium oxysporum ATCC 11739, and two yeasts, Candida albicans ATCC 12354 and Saccharomyces cerevisiae ATCC 4078 [7]. Every pathogenic strain was cultivated for 24 ho at 37 oC on Muller Hilton Agar (MHA, Merck) plates. EtOH dissolved compounds 1 - 2, resulting in concentrations ranging from 16 to 256 %u00b5g/mL. Each well contained 20 %u00b5L of sample and 180 %u00b5L of a bacterial culture containing 106 CFU mL-1 in Muller Hilton Broth (MHB, Merck). An Elisa reader (RNE-9002, USA) was used to measure the mixture%u2019s optical density (OD) at 600 nm after it had been incubated at 37 %u00b0C. The MIC was determined to be the lowest concentration at which no growth was observed. Three runs of the tests were conducted. The positive controls, which contained MHB and bacterial suspension in place of the tested sample, and the negative control, which contained MHB and Tween, underwent identical processes. As reference chemicals, streptomycin and tetracycline were employed for Gram (+) and Gram (%u2013) bacteria, respectively, while nystatin was utilized for yeasts and fungi.2.5. Moquisto larvicidal activity The larvicidal activity of the investigated compounds was assessed against Aedes aegypti and Aedes albopictus, as detailed