Table 2. Description of studies used in the meta-analysis of antimicrobial activity of propolis extract

Source	Study location	Extract method	N	EPc	Control	Bacterial species
Abdullah et al. (2020)	Brunei Darussalam	Ethanol	55	2 g/L	Negative	Basillus subtilis and Staphylococcus aureus
Abdullah et al. (2019)	Brunei Darussalam	Ethanol	18	2 mg/mL; 8 mg/mL	Negative	Staphylococcus aureus, and Pseudomonas aeruginosa
Seibert et al. (2019)	Brazil	Ethanol, hexane, ethyl acetate	36	50 mg/mL	Negative	Staphylococcus saprophyticus, Listeria monocytogenes, and Enterococcus faecalis
Khodayari et al. (2019)	Iran	Ethanol	4	2%	Negative	Escherichia coli
Rezaeigolestani et al. (2017)	Iran	Ethanol	12	2%	Negative	Staphylococcus aureus, and V. parahaemolyticus
Kujumgiev et al. (1999)	Bulgaria	Ethanol	6	0.1%	Negative	Streptococcus aureus
Oliveira et al. (2017)	Portugal	Ethanol	12	20 uL	Negative	Staphylococcus aureus, and Salmonella Typhimurium
Airen et al. (2018)	India	Ethanol	60	5%; 20%	Negative	L. acidophilus, and Streptococcus mutans
Tosi et al. (2007)	Argentina	Ethanol	10	1.4 mg	Negative	Escherichia coli

N, sample size; EPc, extract of propolis concentrations.