Bioencapsulation of probiotic Lactococcus lactis subsp. lactis on Artemia franciscana nauplii: Effects of encapsulation media on Nauplii survival and probiotic recovery

Aims: This study aimed to investigate the suitability and efficacy of various encapsulation media in bioencapsulating the probiotic Lactococcus lactis subsp. lactis in Artemia franciscana nauplii. The impact of the encapsulation media on nauplii survival and probiotic recovery was also determined. Methodology and results: Various encapsulation media (sodium alginate, palm oil, starch, gum Arabic and gelatin) were prepared by dissolving the respective media in artificial sea water. Each media was prepared in four different concentrations: 0.25, 0.5, 1.0 and 2.0 g/L. To determine the suitability of encapsulation media on the survivability of A. franciscana, survival rate (SR) of Artemia nauplii was determined after 8 hours post-encapsulation. Instar II stage Artemia nauplii at 1 nauplii per mL was used for each replicate. The result revealed that A. franciscana reached 100 % SR in the encapsulation media at ≤ 0.5 g/L. All media enabled > 23 % recovery of L. lactis subsp. lactis from encapsulated A. franciscana, which is similar (p > 0.05) to the recovery of free-cells (non-encapsulated) of L. lactis subsp. lactis. Noticeably in sodium alginate (E1) treatment, the total counts of L. lactis subsp. lactis in bioencapsulated A. franciscana were the highest among others, accounting for 2.44 × 107 CFU/mL per A. franciscana tissue homogenate. Conclusion, significance and impact of study: Artemia nauplii bioencapsulated with L. lactis subsp. lactis using 0.5 g/L sodium alginate as encapsulation medium has the highest SR for nauplii and bioencapsulation efficiency, respectively. This result provides a basic guideline for Artemia bioencapsulation in fish/shrimp larval culture.

Effect of Probiotics against Marine Pathogenic Bacteria on Artemia franciscana.

Presently an effort has been made to determine the effectiveness of probiotics against marine pathogenic bacterial load ingested by Artemia franciscana nauplii. In this experiment Artemia franciscana nauplii was allowed to ingest pathogenic bacterial strains, viz. Escherichia coli, Salmonella typhi, Salmonella paratyphi, Vibrio cholerae and Shigella sp. Probiotic organism (Bioremid) was used against the pathogenic strains on Artemia franciscana nauplii. On completion of the experiment it was observed that the use of Probiotic organism (Bioremid) reduced the pathogenic bacterial load, especially that of Shigella sp. on Artemia franciscana.

Effects of salinity on growth and survival in five Artemia franciscana (Anostraca: Artemiidae) populations from Mexico Pacific Coast

Salinity is an important factor influencing growth and survival of aquatic organisms such as Artemia, a valuable aquaculture species. This study evaluated the effects of salinity on A. franciscana populations from different water bodies in Mexico’s Pacific Coast. With this purpose, five autochthonous bisexual Artemia populations were tested to assess their survival and growth values against salinities of 40, 60, 80, 100 and 120g/l, under laboratory conditions (25±2ºC; pH 8-10; constant light and aeration). The organisms were fed with 100mL of rice bran and 2L of Tetraselmis suecica (500 000cel/ml). The culture experiments were made in 200L plastic tanks, and survival and growth final values were obtained after 21 culture days. Survival and growth curves were determined by a regression analysis (R²). The significant differences between salinities were determined by ANOVA test (p<0.05). The best survival and growth rates were found at salinities of 100-120g/l. When the Mexican Artemia populations were cultivated at 40g/l of salinity, 100% mortality was observed in the juvenile stage. This study determined that survival and growth values of A. franciscana populations increased with salinity. The five A. franciscana populations presented significant differences in their survival rate under various salinity regimes. The studied populations experienced high mortality at salinities under 60g/l and over 200g/l, and especially during the metanauplius stage. The present study confirms that growth rates in Mexican A. franciscana populations from Pacific Coast habitats are not inversely proportional to salinity. These A. franciscana populations should be cultured at 100-120g/l of salinity to obtain better survival and growth rates. This data is useful to improve culture systems in aquaculture biomass production systems. Rev. Biol. Trop. 59 (1): 199-206. Epub 2011 March 01.

La salinidad es el factor más importante que modifica el crecimiento y la sobrevivencia de las poblaciones mexicanas de Artemia en el mundo. El efecto de este factor en las poblaciones costeras del Pacífico Mexicano ha sido poco estudiado. Cinco poblaciones bisexuales de Artemia provenientes de cuerpos de aguas costeras del Pacífico Mexicano, se estudiaron para determinar el efecto que tiene la salinidad de 40, 60, 80, 100 y 120g/l sobre la sobrevivencia y el crecimiento, en condiciones de laboratorio (25±2ºC, pH 8-10; luz y aireación continua). Los experimentos de cultivo fueron realizados en tanques de plástico de 200l. Los valores finales de sobrevivencia y crecimiento fueron determinados después de 21 días de cultivo. Los organismos fueron alimentados con 100ml de salvado de arroz y 2l de Tetraselmis suecica (500cel/ml). Las curvas de sobrevivencia y crecimiento fueron determinadas usando un análisis de regresión (R²). Las diferencias significativas entre los valores promedio a las distintas salinidades fueron determinadas por una prueba de ANDEVA (p<0.05). Las mejores tasa de sobrevivencia y crecimiento se encontraron a la salinidad de 100-120g/l. Cuando las poblaciones mexicanas fueron cultivadas a 40 g/l de salinidad, hubo una mortalidad del 100% de los organismos en estadio juvenil. A la salinidad de 80g/l, los valores de sobrevivencia y crecimiento, fueron menores que cuando se cultivaron entre 100 y 120g/l. Las cinco poblaciones bisexuales de A. franciscana presentaron diferencias significativas en sus tasas de sobrevivencia bajo las salinidades estudiadas. Las tasas de sobrevivencia fueron afectadas por la salinidad. Las poblaciones estudiadas experimentaron alta mortalidad a salinidades por debajo de 60 g/l y por arriba de 200g/l. Es importante mencionar que las altas mortalidades se observaron en el estadio metanauplios. El presente trabajo confirma que las tasas de crecimiento de las poblaciones que costeras del Pacífico Mexicano de A. franciscana no son inversamente proporcionales a la salinidad. Las poblaciones de A. franciscana deben de ser cultivadas a una salinidad de 100-120g/l para obtener mejores tasas de sobrevivencia y crecimiento. Estos datos permiten realizar mejoras en los sistemas de cultivo de este crustáceo para la obtención de biomasa para la acuicultura.

Bioactive dihydroxyfuranonaphthoquinones from the bark of Tabebuia incana A.H. Gentry (Bignoniaceae) and HPLC analysis of commercial pau d'arco and certified T.incana bark infusions

Tabebuia incana A.H. Gentry (Bignoniaceae) is a tree from the Brazilian Amazon having medicinal uses and is one several Tabebuia spp. known as pau d'arco or palo de arco in this region. Fractionation of the bark ethanolic extract afforded a mixture of 5 and 8-hydroxy-2-(1-hydroxyethyl)naphtho[2,3-b]furan-4,9-diones (1 and 2, respectively) identified on the basis of nuclear magnetic resonance (NMR), infrared (IR) and mass (MS) spectra, whose in vitro antimalarial and antitumor activity have been shown previously. This is the first study on T. incana bark, and 2 are described in this species for the first time. Also, high performance liquid chromatography (HPLC) analysis of T. incana bark tea revealed the presence of the 1 + 2 mixture peak corresponding to a concentration in the range 10-6-10-5 M. The chromatograms of teas prepared from commercial pau d' arco and T. incana bark were also studied and the presence of the 1 + 2 peak has potential for quality control of commercial plant materials.

Tabebuia incana A.H. Gentry (Bignoniaceae) é uma árvore da Amazônia brasileira com usos medicinais. É uma de várias espécies de Tabebuia conhecidas como pau d'arco ou palo de arco nesta região. O fracionamento do extrato etanólico das cascas resultou no isolamento da mistura de 5 e 8-hidróxi-2-(1-hidroxietil)nafto[2,3-b]furano-4,9-dionas (1 e 2, respectivamente), identificadas com base em seus espectros de ressonância magnética nuclear (RMN), infravermelho (IV) e massa (EM), e cujas atividades antimalárica e antitumoral in vitro foram mostradas previamente. Este é o primeiro estudo das cascas de T. incana e a primeira vez que o composto 2 é descrito nesta espécie. Análises por cromatografia liquida de alto empenho (CLAE) do chá das cascas de T. incana revelaram a presença de um pico correspondente à mistura de 1 + 2, permitindo inferir uma concentração na faixa de 10-6-10-5 M desses componentes no chá. Os cromatogramas de chás (infusões) preparados a partir das cascas de pau d' arco commercial and T. incana certificada também foram estudados. A verficação da presença do pico das substâncias 1 + 2 nos cromatogramas tem potencial contribuição para o controle de qualidade de material vegetal comercial.

Screening of plants found in Amazonas State for lethality towards brine shrimp

226 methanol and water extracts representing 74 mainly native plant species found in Amazonas State, Brazil, were tested at a standard concentration of 500 g/mL for lethality towards larvae of the brine shrimp species Artemia franciscana. Several cytotoxic plant species were identified in this work: Aspidosperma marcgravianum, A. nitidum, Croton cajucara, Citrus limetta, Geissospermum argenteum, Minquartia guianensis, Piper aduncum, P. amapense, P. capitarianum, P. tuberculatum and Protium aracouchini. The results were analyzed within the context of the available traditional knowledge and uses for these plants.

Foram testados 226 extratos metanólicos e aquosos de 74 espécies vegetais (a maioria nativas) encontradas no Estado do Amazonas, Brasil, para letalidade às larvas da espécie microcrustácea Artemia franciscana na concentração teste de 500 g/mL. Várias espécies citotóxicas foram identificadas nesse estudo: Aspidosperma marcgravianum, A. nitidum, Citrus limetta, Croton cajucara, Geissospermum argenteum, Minquartia guianensis, Piper aduncum, P. amapense, P. capitarianum, P. tuberculatum e Protium aracouchini. Os resultados foram analisados levando em consideração as informações populares, quando disponíveis.