Prophylactic effect of Andrographis paniculata extracts against Streptococcus agalactiae infection in Nile tilapia (Oreochromis niloticus).
J Biosci Bioeng
; 107(5): 579-82, 2009 May.
Article
em En
| MEDLINE
| ID: mdl-19393561
ABSTRACT
Six herbs were assessed for their antimicrobial activity against Streptococcus agalactiae, a major fish pathogen causing streptococcosis. Each herb was extracted with 3 solvents water, 95% ethanol, and methanol. Using swab paper disc assays, aqueous extracts of Andrographis paniculata and Allium sativum produced the largest (27.5 mm) and smallest (10.3 mm) inhibition zones, respectively. Determination of minimal inhibitory concentration (MIC) of herb extracts against S. agalactiae showed that the aqueous extract of A. paniculata had the lowest MIC value (31.25 microg/mL). Aqueous extract of A. sativum was the only herb extract with a MIC > 500 microg/mL. Based on mortalities in 2 weeks after intraperitoneal S. agalactiae injection, the median lethal dose (LD(50)) of S. agalactiae for Nile tilapia (Oreochromis niloticus) was 3.79 x 10(5) CFU/mL. In vivo experiments showed that fish feed supplemented with either A. paniculata leaf powder or dried matter of A. paniculata aqueous extract reduced mortality of S. agalactiae infected Nile tilapia. In addition, no mortality was found in fish receiving dried matter of A. paniculata aqueous extract supplemented feeds at ratios (w/w) of 436 and 535. During 2 weeks of feeding with A. paniculata supplemented feeds, no adverse effects on appearance, behavior, or feeding responses were observed.
Texto completo:
1
Base de dados:
MEDLINE
Métodos Terapêuticos e Terapias MTCI:
Terapias_biologicas
/
Plantas_medicinales
Assunto principal:
Infecções Estreptocócicas
/
Streptococcus agalactiae
/
Extratos Vegetais
/
Tilápia
/
Andrographis
/
Doenças dos Peixes
Idioma:
En
Revista:
J Biosci Bioeng
Ano de publicação:
2009
Tipo de documento:
Article
País de afiliação:
Tailândia