Table 6.

In vitro antimicrobial activity of P. curatellifolia.

Plant part	Solvent	Experimental model	Key findings	References
Stem	Aqueous, Diethyl ether, Methanol, Hexane	Extract concentration – 2.8 g/100 mL Microorganisms tested: Pseudomonas aeruginosa, Salmonella typhi, Klebsella spp, Bacillus aureus, Escherichia coli, Bacillus subtilis and Staphylococcus aureus	Aqueous extracts inhibited microbial growth and most effective against S. aureus and Klebsiella spp. methanolic fraction was effective against B. subtilis and P. aeruginosa while diethyl ether and n-hexane had no antimicrobial activity.	[33]
Leaves	Dichloromethane-methanol mixture (50 % v/v), hexane, DCM, acetone, ethyl acetate, ethanol, methanol, and water	Extract concentration: 0.4–200 μg/mL Microorganisms tested: Broth microdilution with nosocomial pathogens including Mycobacterium smegmatis 155 mc2, Candida krusei, Klebsiella pneumoniae (ATCC 700603) and Staphylococcus aureus (ATCC 9144)	Mycobacterium smegmatis was the most susceptible to most extracts. The methanol and ethanol extracts were the most active against M. smegmatis with an MIC of 25 μg/mL. Klebsiella pneumoniae and Staphylococcus aureus showed resistance against all extracts tested. Antifungal properties of P. curatellifolia extracts were attributed to β-sitosterol.	[36]
	Dichloromethane-methanol mixture (50 % v/v), hexane, DCM, acetone, ethyl acetate, ethanol, methanol, and water	Extract concentration: 0–1000 μg/mL Microorganisms used: Broth microdilution with Mycobacterium smegmantis	Acetonic extracts had the lowest MIC at 6.2 μg/mL, followed by ethanol (12.5 μg/mL), with methanol and ethyl acetate at 50 μg/mL biofilm formation by M. smegmantis was inhibited by ethanol, dichloromethane, and water extracts.	[38]
Stem bark, root, and leaves	Water, ethanol, and methanol	Extract concentration: 50–500 mg/mL Microorganisms used: Staphylococcus aureus, Streptococcus mutans and Lactobacillus spp.	Methanolic extracts had high inhibitory activity against all three microbes.	[83]
Root bark	Ethyl acetate	Microorganisms used:Candida albicans (ATCC 90028), Cryptococcus neoformans (ATCC 90112), Aspergillus niger (AZN 8240) and Candida albicans clinical isolates	Crude extracts showed lower MIC against C. neoformans and A. niger compared to control (clotrimazole)	[40]
Trunk bark	Ethanol	Extract concentrations: 0.25–2.5 mg/mL Microorganisms used: Trichophyton rubrum, Trichophyton schoenleinii, and Microsporum canis	The extracts were most effective against T. schoenleinii (MIC – 0.75 mg/mL), while the MIC for T. rubrum and M. canis was 1.5 mg/mL	[41]
Stem bark	Methanol, ethyl acetate and n-butanol	Extract concentration: 50 mg/mL Microorganisms used: Cup plate method with Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa and Bacillus subtilis	The ethyl acetate fraction was most effective, with its activity against S. aureus comparable to 0.01 mg/mL ampicillin. Additionally, the same fraction sowed a MIC and MBC of 0.78 mg/mL and 6.25 mg/mL against S. aureus.	[35]
Bark	Ethanol	Extract concentration: 0.8–25 mg/mL Microorganisms used: Microdilution assay with oral pathogens Actinomyces naeslundii, Actinomyces israelii, Streptococcus mutans (Gram positive); Actinobacillus actinomycetemcomitans, Privotella intermedia, Porphyromonus gingivalis (Gram negative)	Extracts were active against Gram negative oral pathogens with MIC and MBC in the range 1.6–6.3 mg/mL: MIC of 3.1–12.5 mg/mL for Gram negative pathogens with MBC of 25 mg/mL against Gram positive P. gingivalis	[84]

MIC = minimum inhibitory concentration, MBC = minimum bactericidal concentration.