Renata Albuquerque Costa

Susceptibilidade "in vitro" a antimicrobianos de estirpes de Vibrio spp isoladas de camarões (Litopenaeus vannamei) e de água de criação destes animais provenientes de uma fazenda de camarões no Ceará Nota prévia

Foram feitos ensaios de susceptibilidade a antibioticos em 48 cepas de Vibrio isoladas do cultivo do Litopenaeus vannamei no Ceara. Para os testes de difusao foram utilizados 11 antibioticos. A especie que apresentou maior percentagem de resistencia aos antimicrobianos foi V. cholerae, onde 33,33% das 12 cepas testadas mostraram-se resistentes a sulfazotrim, 25% a ampicilina e 33,33% a ceftriaxona.

Antibiotic-Resistant Vibrios in Farmed Shrimp

Antimicrobial susceptibility pattern was determined in 100 strains of Vibrio isolated from the Litopenaeus vannamei shrimp and identified phenotypically. A high antibiotic-resistance index (75%) was observed, with the following phenotypic profiles: monoresistance (n = 42), cross-resistance to β-lactams (n = 20) and multiple resistance (n = 13). Plasmid resistance was characterized for penicillin (n = 11), penicillin + ampicillin (n = 1), penicillin + aztreonam (n = 1), and ampicillin (n = 1). Resistance to antimicrobial drugs by the other strains (n = 86) was possibly mediated by chromosomal genes. The findings of this study support the conclusion that the cultured shrimps can be vehicles of vibrios resistant to β-lactam and tetracycline.

Thiocarbamates from Moringa oleifera Seeds Bioactive against Virulent and Multidrug-Resistant Vibrio Species

Prospect of antibacterial agents may provide an alternative therapy for diseases caused by multidrug-resistant bacteria. This study aimed to evaluate the in vitro bioactivity of Moringa oleifera seed extracts against 100 vibrios isolated from the marine shrimp Litopenaeus vannamei. Ethanol extracts at low (MOS-E) and hot (MOS-ES) temperature are shown to be bioactive against 92% and 90% of the strains, respectively. The most efficient Minimum Inhibitory Concentration (MIC) levels of MOS-E and MOS-ES against a high percentage of strains were 32 µg mL−1. Bioguided screening of bioactive compounds showed that the ethyl acetate fraction from both extracts was the only one that showed antibacterial activity. Vibriocidal substances, niazirine and niazimicine, were isolated from the aforementioned fraction through chromatographic fractionation.

Antibiotic Resistance in Salmonella: A Risk for Tropical Aquaculture

Salmonelas are rod-shaped, non-spore-forming Gram-negative facultative anaerobes measuring 0.7-1.5 by 2-5 μm. With the exception of the serovars Gallinarum and Pullorum, salmonelas are motile organisms. They are classified according to morphology and staining pattern and are divided into serotypes and serovars based on their reaction to somatic (O) and flagellar (H) antigens (Bremer et al., 2003). According to Kumar et al.(2003), the genus Salmonella has over 2,000 serovars. Two of these―Saintpaul and Newport―have been isolated from seafood (Ponce et al., 2008).