The antibacterial activities of mikanolide and its derivatives.

OBJECTIVE: The sesquiterpene, mikanolide, was found to possess antibacterial activity. As a result, a structure-activity relationship study was carried out on mikanolide and eleven of its derivatives. METHODS: Mikanolide and two of its derivatives were isolated from organic extract of Mikania micrantha using chromatographic methods. Nine additional derivatives were synthesized and all were investigated for their antibacterial activity against the Gram positive pathogen Staphylococcus aureus and beta haemolytic Streptococcus group A (BHSA) as well as the Gram negative Escherichia coli using the disk diffusion assay. RESULTS: The investigation revealed that only four of the derivatives displayed antibacterial activity and only pathogens Staphylococcus aureus and beta haemolytic Streptococcus group A were susceptible at a concentration of 100 microg per disk. However there was an increase in activity for three of the derivatives in comparison to mikanolide. CONCLUSION: This study underscores the potential for phytochemicals from locally available plants to be further investigated and developed as antibacterial agents.

Investigation of essential oil extracts from four native Jamaican species of Bursera for antibacterial activity.

OBJECTIVE: Bacterial infection with organisms resistant to antibiotics have increased during the last few decades worldwide. Because of this increase, the authors decided to subject the essential oils from the stem, leaves and fruits of the four native Jamaica species of Bursera to microbial studies. METHODS: Steam distillate extracts from different parts of four native Jamaican spp of Bursera simaruba (Red Birch), Bursera lunanii (Black Birch), Bursera hollickii and Bursera aromatica (Siboney) were tested for their antibacterial activity against six common pathogens: Escherichia coli, Proteus mirabilis, Pseudomonas aeruginosa, Staphylocococcus aureus, methicillin resistant Staphylococcus aureus (MRSA) and beta-haemolytic Streptococcus group A (BHSA) using a disk diffusion assay. RESULTS: The investigation revealed that extracts from two of the four plants tested were active against all the pathogens. These were extracts from the fruits and stems of B. simaruba and those from the fruit of B. lunanii. CONCLUSION: This study gives credence to the ongoing search for locally available plants whose extracts possess significant antimicrobial activity. This may be useful in the development of naturally derived pharmaceuticals.

Investigation of essential oil extracts from four native Jamaican species of Bursera for antibacterial activity / Investigación de los extractos de aceites esenciales a partir de cuatro especies de bursera, endémicas de jamaica, para la determinación de su actividad antibacteriana

OBJECTIVE: Bacterial infection with organisms resistant to antibiotics have increased during the last few decades worldwide. Because of this increase, the authors decided to subject the essential oils from the stem, leaves and fruits of the four native Jamaica species of Bursera to microbial studies. METHODS: Steam distillate extracts from different parts of four native Jamaican spp of Bursera simaruba (Red Birch), Bursera lunanii (Black Birch), Bursera hollickii and Bursera aromatica (Siboney) were tested for their antibacterial activity against six common pathogens: Escherichia coli, Proteus mirabilis, Pseudomonas aeruginosa, Staphylocococcus aureus, methicillin resistant Staphylococcus aureus (MRSA) and beta-haemolytic Streptococcus group A (BHSA) using a disk diffusion assay. RESULTS: The investigation revealed that extracts from two of the four plants tested were active against all the pathogens. These were extracts from the fruits and stems of B. simaruba and those from the fruit of B. lunanii. CONCLUSION: This study gives credence to the ongoing search for locally available plants whose extracts possess significant antimicrobial activity. This may be useful in the development of naturally derived pharmaceuticals.

Objetivo: La infección bacteriana con organismos resistentes a los antibióticos ha aumentado a nivel mundial durante las últimas décadas. Debido a este aumento, los autores decidieron someter a estudios microbianos los aceites esenciales de cortezas, hojas y frutos de cuatro especies de Bursera endémicas de Jamaica. Métodos: Los extractos destilados al vapor, de diferentes partes de cuatro spp endémicas de Jamaica, a saber, Bursera simaruba (abedul rojo), Bursera lunanii (abedul negro), Bursera hollickii y Bursera aromatica (Siboney), fueron analizados mediante un ensayo de difusión en disco, a fin de determinar su actividad antimicrobiana frente a seis patógenos comunes: Escherichia coli, Proteus mirabilis, Pseudomonas aeruginosa, Staphylocococcus aureus, Staphylococcus aureus resistente a la meticilina (MRSA) y el Streptococcus betahemolítico del grupo A (EBHA). Resultados: La investigación reveló que los extractos de dos de las cuatro plantas sometidas a examen eran activas contra todos los patógenos. Estos fueron los extractos de frutos y ramas de B simaruba y los de frutos de B lunanii. Conclusión: Este estudio da crédito a la investigación que se lleva a cabo con el propósito de determinar qué extractos de plantas disponibles localmente poseen una actividad antimicrobiana significativa. Esto puede resultar útil para el desarrollo de productos farmacéuticos derivados naturalmente.

Investigation of plants used in Jamaican folk medicine for anti-bacterial activity.

We have started a systematic scientific study of folklore medicinal plants currently used as alternative medicine in Jamaican society. In this initial study, extracts of plants widely used by the islanders are studied for antibacterial activity against five common pathogens; Streptococcus group A, Staphylococcus aureus, Proteus mirabilis, Pseudomonas aeruginosa and Escherichia coli. These studies revealed that 25% (approx.) of the plant extracts had antimicrobial activity against at least one of the microbes used. Subsequent to these observations, extracts from Mikania micrantha were examined in detail. This led to the isolation of two sesquiterpenoids, mikanolide and dihydromikanolide, with activity against S. aureus and C. albicans. The results suggest that traditional folk medicine could be used as a guide in our continuing search for new natural products with potential medicinal properties.

Investigation of plants used in Jamaican folk medicine for anti-bacterial activity

We have started a systematic scientific study of folklore medicinal plants currently used as alternative medicine in Jamaican society. In this initial study, extracts of plants widely used by the islanders are studied for antibacterial activity against five common pathogens; Streptococcus group A, Staphylococcus aureus, Proteus mirabilis, Pseudomonas aeruginosa and Escherichia coli. These studies revealed that 25 percent (approximately) of the plant extracts had antimicrobial activity against at least one of the microbes used. Subsequent to these observations, extracts from Mikania micrantha were examined in detail. This led to the isolation of two sesquiterpenoids, mikanolide and dihydromikanolide, with activity against S. aureus and C. albicans. The results suggest that traditional folk medicine could be used as a guide in our continuing search for new natural products with potential medicinal properties.(Au)