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84 PROCEEDINGS OF INTERNATIONAL SCIENTIFIC CONFERENCE ON APPLIED BIOTECHNOLOGYvalue of 400 %u03bcg/mL against two Gram (%u2013) bacteria P. aeruginosa and E. coli, and the yeast C. glabrata [14]. It also displayed intense antimicrobial activity with MIC of 50 %u03bcg/mL and MBC/MFC value of 200 %u03bcg/mL against C. albicans [14]. Three minor flavonoids derived from green propolis, namely quercetin 3-methyl ether, 3,3%u2019-O-dimethylquercetin, and 5-O-methyl ether, also strongly controlled the growth of the Gram-positive bacteria B. subtilis, and S. aureus with MIC values of 32-64 %u03bcg/mL [11].3.4. Mosquito larvicidal activity Larvicidal activities of flavonoids 1-2 against fourth-instar mosquito larvae of Ae. aegypti, and Ae. albopictus for 24-h and 48-h treatments are provided in Table 3. It has been noted that the isolates having LC50<50 %u00b5g/mL were considered strong active agents, but moderate activity with 50 %u00b5g/mL < LC50 < 100 %u00b5g/mL, and weak activity with 100 %u00b5g/mL < LC50 < 750 %u00b5g/mL, as well as those products in the range of LC50> 750 %u00b5g/mL will be inactive [11]. Santin (1) showed strong inhibitory activity with both 24-h and 48-h LC50 < 50 %u00b5g/mL, whereas sakurannetin (2) had moderately inhibitory activity with 24-h and 48-h LC50> 50 %u00b5g/mL. For Table 3, the 24-h and 48-h LC90 values of compound 1 were also lower than those of compound 2. This reflects that flavones seem better than flavones in larvicidal actions. Several other flavonoids from green propolis, such as eriodictyol 5-O-methyl ether, 5,4%u2019-dihydroxy-6, 7-dimethoxyflavanone, licoflavanone, and macarangaflavanone B, were also recorded to exhibit strong or moderate mosquito larvicidal activity against Ae. aegypti and Ae. albopictus fourth instar larvae with the 24 h LC50 values of 29.62-55.89 %u00b5g/mL [11]. Yaseen and Ali in 2022 reported that the alcoholic extracts of Iraqi propolis were almost complete in killing Culex pipiens molestus third instar larvae for 3 days of treatment [15]. The