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J Chromatogr Sci ; 50(8): 666-72, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22595260


This paper describes the determination of fatty acid composition of coffee, citrus and rum distillery wastes using reversed-phase high-performance liquid chromatography (RP-HPLC). Lipid extracts of the waste samples are derivatized with phenacyl bromide and their phenacyl esters are separated on a C8 reversed-phase column by using continuous gradient elution with water and acetonitrile. The presence of saturated and unsaturated fatty acids in quantifiable amounts in the examined wastes, as well as the high percentage recoveries, are clear indications that these wastes have potential value as inexpensive sources of lipids. The HPLC procedures described here could be adopted for further analysis of materials of this nature.

Acetofenonas/química , Agricultura , Cromatografia Líquida de Alta Pressão/instrumentação , Cromatografia Líquida de Alta Pressão/métodos , Ácidos Graxos/análise , Resíduos Industriais/análise , Bebidas Alcoólicas , Citrus , Café , Jamaica
West Indian Med J ; 59(3): 249-52, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21291101


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.

Lactonas/farmacologia , Sesquiterpenos de Germacrano/farmacologia , Antibacterianos/farmacologia , Testes de Sensibilidade a Antimicrobianos por Disco-Difusão , Humanos , Staphylococcus aureus/efeitos dos fármacos , Streptococcus pyogenes/efeitos dos fármacos , Relação Estrutura-Atividade
J Chromatogr Sci ; 47(8): 674-80, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19772744


Jamaican agro-industries generate large quantities of wastes, which are either discarded or under-utilized. In order to evaluate the possible utilization of these wastes, it is necessary that the profiles of the major biochemical groups be developed. This paper describes the determination of the amino acid composition of coffee, citrus, and rum distillery wastes using a reversed-phase high-performance liquid chromatography method. Acid hydrolysates of the wastes are derivatized with phenylisothiocyanate. They are analyzed as their phenylthiocarbamyl derivatives and determined quantitatively using norleucine as the internal standard. The presence of all the 17 amino acids investigated, nine of which include those essential for animal nutrition, are observed in the samples investigated, suggesting a high quality of protein with implications in the formulation of animal feeds.

Agricultura , Aminoácidos/análise , Aminoácidos/química , Cromatografia Líquida de Alta Pressão/métodos , Resíduos Industriais/análise , Isotiocianatos/química , Jamaica
West Indian Med J ; 56(1): 5-10, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17621837


Epingaione (4-Methyl-1-(5-methyl-2, 3,4,5-tetrahydro-[2,3']bifuranyl-5-yl)-pentan-2-one) was isolated as one of the major lipophilic secondary metabolites from the leaves and stems of Bontia daphnoides L. The compound gave 79.24% and 50.83% anti-proliferation/cytotoxic activity on the human SH-SY5Y neuroblastoma and TE-671 sarcoma cells in vitro at 50 pg/mL, respectively. Epingaione was transformed into eleven derivatives under laboratory conditions using ethanol, some gave greater anti-proliferation/cytotoxic activity on the cancer cell lines tested. One of the derivatives (compound 2) with enhanced cytotoxic activity was elucidated as 5'-Ethoxy-5-methyl-5-(4-methyl-2-oxo-pentyl)-2,3,4,5-tetrahydro-5'H-[2,3']bifuranyl-2'-one. Both epingaione and compound 2 caused an accumulation of arrested or dead SH-SY5Y neuroblastoma in the m-phase of the cell cycle as revealed by the m-phase specific marker KE 67.

Furanos/farmacologia , Myoporaceae , Neuroblastoma/tratamento farmacológico , Pentanonas/farmacologia , Fitoterapia , Sarcoma/tratamento farmacológico , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular , Ensaios de Seleção de Medicamentos Antitumorais , Furanos/química , Humanos , Pentanonas/química , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Folhas de Planta , Caules de Planta
West Indian Med J ; 56(1): 22-5, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17621840


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.

Infecções Bacterianas/tratamento farmacológico , Bursera , Fitoterapia , Extratos Vegetais , Testes de Sensibilidade a Antimicrobianos por Disco-Difusão , Frutas , Humanos , Caules de Planta