The study evaluates screening methods to determine antibacterial activity of natural products. Natural products from plants, fungi, and lichens were tested against Staphylococcus aureus ATCC 25923 and Escherichia coli ATCC 25922 using agar diffusion (well and disc variants), bioautographic (direct and indirect variants), and microdilution methods. The well variant of the agar diffusion method was found to be more sensitive than the disc variant. The direct variant of the bioautographic method showed greater sensitivity compared to the indirect variant. Both bioautographic and diffusion techniques had similar sensitivity, but the latter provided better conditions for microbial growth. The study also discussed the best conditions for determining the minimum inhibitory concentration (MIC). The agar diffusion well variant was more sensitive than the disc variant. The direct bioautographic method was more sensitive than the indirect variant. The diffusion method provided better conditions for microbial growth. The study also discussed the best conditions for determining the minimum inhibitory concentration (MIC). The results showed that the well variant of the agar diffusion method was more sensitive than the disc variant. The direct variant of the bioautographic method was more sensitive than the indirect variant. The study also discussed the best conditions for determining the minimum inhibitory concentration (MIC). The results indicated that the well variant of the agar diffusion method was more sensitive than the disc variant. The direct variant of the bioautographic method was more sensitive than the indirect variant. The study also discussed the best conditions for determining the minimum inhibitory concentration (MIC). The results showed that the well variant of the agar diffusion method was more sensitive than the disc variant. The direct variant of the bioautographic method was more sensitive than the indirect variant. The study also discussed the best conditions for determining the minimum inhibitory concentration (MIC).The study evaluates screening methods to determine antibacterial activity of natural products. Natural products from plants, fungi, and lichens were tested against Staphylococcus aureus ATCC 25923 and Escherichia coli ATCC 25922 using agar diffusion (well and disc variants), bioautographic (direct and indirect variants), and microdilution methods. The well variant of the agar diffusion method was found to be more sensitive than the disc variant. The direct variant of the bioautographic method showed greater sensitivity compared to the indirect variant. Both bioautographic and diffusion techniques had similar sensitivity, but the latter provided better conditions for microbial growth. The study also discussed the best conditions for determining the minimum inhibitory concentration (MIC). The agar diffusion well variant was more sensitive than the disc variant. The direct bioautographic method was more sensitive than the indirect variant. The diffusion method provided better conditions for microbial growth. The study also discussed the best conditions for determining the minimum inhibitory concentration (MIC). The results showed that the well variant of the agar diffusion method was more sensitive than the disc variant. The direct variant of the bioautographic method was more sensitive than the indirect variant. The study also discussed the best conditions for determining the minimum inhibitory concentration (MIC). The results indicated that the well variant of the agar diffusion method was more sensitive than the disc variant. The direct variant of the bioautographic method was more sensitive than the indirect variant. The study also discussed the best conditions for determining the minimum inhibitory concentration (MIC). The results showed that the well variant of the agar diffusion method was more sensitive than the disc variant. The direct variant of the bioautographic method was more sensitive than the indirect variant. The study also discussed the best conditions for determining the minimum inhibitory concentration (MIC).