Extracts from five indigenous Palestinian medicinal plants including
Rosmarinus officinalis
,
Pisidium guajava
,
Punica granatum
peel, grape seeds and
Teucrium polium
were investigated for antimicrobial and free radical scavenging activities against eight microorganisms, using well diffusion method. The microorganisms included six bacterial isolates (i.e.
Staphylococcus aureus
,
Escherichia coli
,
Pseudomonas aeruginos
,
Klebsiella pneumonia
,
Bacillus subtilis
and
Micrococcus luteus
) and two final isolates (i.e.
Candida albicans
and
Aspergillus niger
). A standard antioxidant assay was performed on the plant extracts to assess their capability in scavenging 2,2-diphenyl-1-picrylhydrazyl (DPPH). Of the five tested plant extract, only
Rosmarinus offcinalisextract contained significant antimicrobial activity against all eight microbial isolates including
Pseudomonas aeruginosa. Extracts from other four plants exhibited a variable antimicrobial activity against all microorganisms, except
Pseudomonas aeruginosa. Significant antioxidant activity was detected in all plant extracts. However, extracts from
Pisidium guajava leaves contained significantly higher antioxidant activity compared to the other extracts tested. The antimicrobial and scavenging activities detected in this in vitro study in extracts from the five Palestinian medicinal plants suggest that further study is needed to identify active compounds to target diseases caused by a wide-spectrum pathogens.
