Research Article

Antibacterial and Antibiotic-Modifying Activity of Methanol Extracts from Six Cameroonian Food Plants against Multidrug-Resistant Enteric Bacteria

Table 3

Minimal inhibitory concentration (MIC) in μg/mL of methanol extracts from the studied plants and chloramphenicol.
(a)

Bacterial strainsTested samples and MIC and MBC and MIC in the presence of PAβN in parenthesis (μg/mL)
P. guajava (leaves)P. guajava (fruits)P. guajava (bark)P. americana (leaves)P. americana (bark)
MICMBCRMICMBCRMICMBCRMICMBCRMICMBCR

Escherichia coli
ATCC873951210241024256256
ATCC105365121024512128256
AG10010241024512256256
AG100A256 (256)5121024256 (256)512 (512)
AG102512 (512)25610244102464 (16)5128128 (64)10248
AG100ATet512 (128)1024512 (128)512 (128)
MC41005121024128512
W311010241024256256

Enterobacter aerogenes
ATCC130482561024512512512
EA-CM64512 (512)1024512 (512)512 (512)
EA3512512256128
EA27128 (128)128 (256)256 (256)
EA289256 (128)512256 (256)512 (512)
EA294102425612810248
EA2981024 (1024)128 (128)10248256 (256)10244

Klebsiella pneumoniae
ATCC1129610245121024
K251210241024256256
K245121024512512
KP551024 (1024)1024512— (—)— (—)
KP63256 (16)512512 (<8)128 (<8)10248

Providencia stuartii
ATCC299165121024
ATCC299645512102410245121024
PS2636512 (512)51210242512256 (256)10244512 (512)
NEA161024 (1024)512102421024 (512)256 (16)10244

Enterobacter cloacae
BM47256 (1024)512512 (512)128 (128)
BM67256 (256)1024512512 (512)256 (256)
ECCI69512 (512)5121024 (1024)— (—)

Pseudomonas aeruginosa
PA015121024128
PA1241024 (1024)1024— (—)1024 (512)

R: MIC/MBC; —: MIC > 1024 or not detected; ( ): values in parenthesis are MIC of substance in the presence of PAβN at 30 μg/mL; values in bold are the best MIC values for the plant extracts.
(b)

Bacterial strainsTested samples and MIC and MBC and MIC in the presence of PAβN in parenthesis (μg/mL)
Citrus sinensisM. indica (leaves)M. indica (bark)Camellia sinensisCoula edulis
MICMBCRMICMBCRMICMBCRMICMBCRMICMBCR

Escherichia coli
ATCC8739642564256512642564
ATCC10536256512256512645128
AG100128102451264
AG100A512 (256)1024— (—)512 (256)1024
AG102128 (<8)102441024 (1024)1024 (1024)256 (256)322568
AG100ATet512 (8)1024 (1024)— (—)256 (256)1024
MC41006410241024102464
W3110325121610241024102464

Enterobacter aerogenes
ATCC1304851210242512512512512
EA-CM64— (16)— (1024)— (—)— (—)64
EA325610245121024128
EA27512 (256)512 (256)512 (256)1024 (1024)256
EA289512 (<8)— (—)512 (—)512 (64)512
EA2941285124102464102416
EA298128 (128)5124— (—)— (—)512 (512)256

Klebsiella pneumoniae
ATCC11296512512
K2128102410246432
K24102410245121024
KP55— (—)1024 (1024)1024 (1024)— (—)1024
KP63256 (<8)1024 (1024)512 (256)256 (64)512

Providencia stuartii
ATCC299165121024512
ATCC299645102451212810248
PS26361024 (<8)512 (512)512 (512)— (—)5125121
NEA16128 (16)10248512 (512)512 (512)1024 (1024)1024112810248

Enterobacter cloacae
BM47256 (16)512512 (512)1024 (1024)1024
BM67512 (512)1024512 (512)256 (256)10244
ECCI69512 (512)— (—)512 (256)

Pseudomonas aeruginosa
PA011285124102432512
PA124— (1024)1024 (512)512 (512)1024 (1024)

R: CMB/CMI; —: MIC > 1024 or not detected; ( ): values in parenthesis are MIC of substance in the presence of PAβN at 30 μg/mL; values in bold are the best MIC values for the plant extracts.
(c)

Bacterial strainsChloramphenicol
MICMBCR

Escherichia coli
ATTC87394164
ATCC10536412832
AG1008648
AG100A64
AG102642564
AG100ATet128
MC41008648
W3110825632

Enterobacter aerogenes
ATCC130488648
EA-CM64128
EA3322568
EA27128
EA289256
EA294812816
EA29832642

Klebsiella pneumoniae
ATCC1129664
K2321284
K241282562
KP55641282
KP63642564

Providencia stuartii
ATCC29916128
ATCC299645642564
PS2636128
NEA16322568

Enterobacter cloacae
BM47256
BM67128
ECCI69256

Pseudomonas aeruginosa
PA0132
PA124256

R: CMB/CMI; —: MIC > 1024 or not detected; values in parenthesis are MIC of substance in the presence of PAβN at 30 μg/mL; values in bold are the best MIC values for the plant extracts.