Application of Chlorophyte ChlB Gene and Cyanophyte NIES Gene in the Detection of Drowning-Related Plankton / 法医学杂志

Objective To construct a polymerase chain reaction-capillary electrophoresis （PCR-CE） detection method using ChlB gene and NIES gene, investigate the method's specificity and sensitivity, and to evaluate its application value in drowning diagnosis. Methods The specific primers ChlB and NIES were designed for the conserved sequence of chlorophyte ChlB gene and cyanophyte NIES gene in GenBank to construct PCR-CE detection method; 50 species of standard DNA samples were amplified; the sensitivity was determined by gradient concentration detection of positive standard samples; 25 actual cadaver lung tissue samples （drowned： 20, natural death： 5） were detected, and the simultaneous detection results of microwave digestion-vacuum filtration-automated scanning electron microscopy （MD-VF-Auto SEM） were simultaneously compared. Results The minimum DNA detection concentration of primers ChlB and NIES was 0.161 ng and 0.109 ng, respectively, which could specifically amplify chlorophyte （Chlorella pyrenoidosa） and cyanophyte ［Microcystis aeruginosa （producing and not producing toxin）］ widespread in water. The product fragments were 156 bp and 182 bp, respectively. The results of non-drowning tissues were negative. Conclusion This method has high sensitivity and specificity. It can be applied to the detection of plankton related to drowning and combined with MD-VF-Auto SEM method, can increase the detection range of plankton related to drowning and improve the evidence power of drowning diagnosis.

Proximate composition of several macroalgae from the coast of Salinas Bay, Ecuador / Composición proximal de varias macroalgas de la costa de Bahía Salinas, Ecuador

Abstract Seaweeds are accessible and important marine organisms found in coastal zones, which have shown their nutritive potential as food or additive. These organisms are relatively abundant in the coastline of Ecuador, but their biochemical composition has not been adequately studied. Therefore, the aim of this research was to evaluate the proximate composition of seven seaweeds (four red, two brown, and one green) collected from Salinas Bay, Ecuador, as a contribution to the knowledge of the nutritional potential of these organisms that belong to this region. Moisture, ash, fat, fiber and protein contents were determined by standard protocols, while carbohydrates were obtained by difference. Energetic content (or caloric profile) was calculated according to the contributions of macromolecules (fats, proteins and carbohydrates). The parameters in highest proportion found in all species were carbohydrates (32.2-45.5 %) and minerals (or ash, 25.8-36.7 %), which play a significant role in human nutrition and the food industry. Furthermore, protein, fiber, and fat contents were relatively low, with values around 4.7-8.0 %, 0.9-5.0 %, and 0.3-3.0 %, respectively, indicating these organisms are a good option as healthy food. According to statistical analysis (ANOVA), each nutritive parameter was significantly different among the species (P < 0.05). Results indicate edible seaweeds from Ecuador have potential as nutritious food that could offer between 1 500-2 000 kcal kg-1, which is higher than many common vegetables.(AU)

Resumen Las macroalgas marinas son organismos accesibles e importantes de las zonas costeras, los cuales han mostrado su potencial como alimentos o aditivos nutritivos. En la línea costera de Ecuador estos organismos son relativamente abundantes, pero su composición bioquímica no ha sido estudiada adecuadamente. En consecuencia, el objetivo de esta investigación fue evaluar la composición proximal de siete especies de macroalgas (cuatro rojas, dos pardas y una verde) que fueron recolectadas en la Bahía de Salinas, Ecuador, como una contribución al conocimiento del potencial nutricional de estos organismos pertenecientes a esta región. Los contenidos de humedad, cenizas, grasa, fibra y proteínas fueron determinadas mediante protocolos estándares, mientras que el contenido de carbohidrato fue obtenido por diferencia. El contenido energético (o perfil calórico) de las macroalgas fue calculado de acuerdo con las contribuciones de las macromoléculas (grasas, proteínas y carbohidratos). Los parámetros encontrados en mayor proporción en todas las especies fueron: carbohidratos (32.2-45.5 %) y minerales (o cenizas, 25.8-36.7 %), los cuales tienen importancia en la nutrición humana y la industria alimentaria. Además, los contenidos de proteína, fibra y grasa fueron relativamente bajos, encontrando valores alrededor de 4.7-8.0, 0.9-5.0, y 0.3-3.0 %, respectivamente, indicando que estos organismos son una buena y saludable opción como alimento. De acuerdo con el análisis estadístico (ANOVA), cada parámetro nutritivo fue significativamente diferente entre especies (P < 0.05). Los resultados indican que las algas comestibles de Ecuador tienen potencial como alimento nutritivo que pueden ofrecer entre 1 500-2 000 kcal kg-1, un aporte energético un poco mayor que muchos vegetales comunes.(AU)

Asymmetric cell division and its role in cell fate determination in the green alga Tetraselmis indica.

The prasinophytes (early diverging Chlorophyta), consisting of simple unicellular green algae, occupy a critical position at the base of the green algal tree of life, with some of its representatives viewed as the cell form most similar to the first green alga, the ‘ancestral green flagellate’. Relatively large-celled unicellular eukaryotic phytoflagellates (such as Tetraselmis and Scherffelia), traditionally placed in Prasinophyceae but now considered as members of Chlorodendrophyceae (core Chlorophyta), have retained some primitive characteristics of prasinophytes. These organisms share several ultrastructural features with the other core chlorophytes (Trebouxiophyceae, Ulvophyceae and Chlorophyceae). However, the role of Chlorodendrophycean algae as the evolutionary link between cellular individuality and cellular cooperation has been largely unstudied. Here, we show that clonal populations of a unicellular chlorophyte, Tetraselmis indica, consist of morphologically and ultrastructurally variant cells which arise through asymmetric cell division. These cells also differ in their physiological properties. The structural and physiological differences in the clonal cell population correlate to a certain extent with the longevity and function of cells.