Vibrio sp. ArtGut-C1, a polyhydroxybutyrate producer isolated from the gut of the aquaculture live diet Artemia (Crustacea)

BACKGROUND: Vibrio species display variable and plastic fitness strategies to survive and interact with multiple hosts, including marine aquaculture species that are severely affected by pathogenic Vibrios. The culturable Vibrio sp. strain ArtGut-C1, the focus of this study, provides new evidence of such phenotypic plasticity as it accumulates polyhydroxybutyrate (PHB), a biodegradable polymer with anti-pathogen activity, particularly in the marine larviculture phase. The strain was isolated from the gut of laboratory-reared Artemia individuals, the live diet and PHB carrier used in larviculture. Its main phenotypic properties, taxonomic status and genomic properties are reported based on the whole-genome sequencing. RESULTS: Vibrio sp. ArtGut-C1 yielded 72.6% PHB of cells' dry weight at 25 C. The genomic average nucleotide identity (ANI) shows it is closely related to V. diabolicus (ANI: 88.6%). Its genome contains 5,236,997- bp with 44.8% GC content, 3,710 protein-coding sequences, 96 RNA, 9 PHB genes functionally related to PHB metabolic pathways, and several genes linked to competing and colonizing abilities. CONCLUSIONS: This culturable PHB-accumulating Vibrio strain shows high genomic and phenotypic variability. It may be used as a natural pathogen biocontrol in the marine hatchery and as a potential cell factory for PHB production.

Actividad antimicrobiana y toxicidad frente a Artemia salina del extracto diclorometánico de raíces de Morinda royoc L / Antimicrobial action and toxicity against Artemia salina of the dichlormethane extract from Morinda royoc L roots

Introducción: las plantas son una fuente de diversidad natural por la gran variedad de compuestos que sintetizan. Particularmente las antraquinonas resultan un importante grupo de metabolitos secundarios con actividad antimicrobiana y antioxidante. Objetivos: evaluar la actividad antimicrobiana del extracto diclorometánico de raíces de Morinda royoc L, así como su toxicidad contra Artemia salina. Métodos: la actividad antimicrobiana se determinó utilizando el método de microdilución en placa de 96 pozos. Se evaluó la actividad del extracto frente a 7 aislados clínicos de Candida spp. y frente a las bacterias Staphylococcus aureus resistente a meticilina, Staphylococcus aureus ATCC 12598, Enterococus faecales, Escherichia coli, Acinetobacter baumanii, Pseudomonas aeruginosa y Klebsiella pneumoniae. La toxicidad del extracto se evaluó mediante el ensayo de letalidad con A salina. Resultados: el extracto crudo fue activo frente a todas las especies de Candida evaluadas. La concentración mínima inhibitoria más baja fue 1,95 µg/mL. El extracto mostró fuerte actividad inhibitoria contra S. aureus, E faecales, y E coli. El valor más bajo de concentración mínima inhibitoria obtenido fue 31,25 µg/mL. El extracto presentó una toxicidad moderada hacia A salina. Conclusiones: los resultados obtenidos demuestran el potencial del extracto diclorometánico de raíces de M. royoc L en el tratamiento de infecciones causadas por bacterias y hongos

Introduction: plants are a source of natural diversity because of the great variety of compounds that they synthesize. Anthraquinones in particular are an important group of secondary metabolites characterized by their antimicrobial and antioxidant action. Objectives: to evaluate the antimicrobial action of dichloromethane extract from Morinda royoc L roots as well as its toxicity against Artemia salina. Methods: the antimicrobial action was determined by using the brooth microdilution in 96-well plate. The extract action against 7 Candida spp clinical isolates and against bacteria such as methicillin-resistant Staphylococcus aureus, Staphylococcus aureus ATCC 12598, Enterococus faecales, Escherichia coli, Acinetobacter baumanii, Pseudomonas aeruginosa and Klebsiella pneumoniae was evaluated. The extract toxicity was measured using brine shrimp (Artemia salina) lethality test. Results: the crude extract proved to be active against all the tested Candida species. The lowest minimal inhibitory concentration was 1,95 µg/mL. The extract showed strong inhibitory action against S aureus, E. faecales, and E coli. The lowest minimal inhibitory concentration was 31.25 µg/mL. The extract presented moderate toxicity against A salina. Conclusions: the results showed the potentialities of dichloromethane extract from M. royoc L. roots for the treatment of bacterial and fungal infections

Avaliaçäo da atividade citotóxica, antiviral e antimicrobiana de Apocynaceae amazônicas / Evaluation of the activity cytotoxic, antiviral and antimicrobial of Apocynaceae Amazonian

A necessidade de se introduzir novos fármacos quimioterápicos é patente. Para tanto, a modelagem molecular, a terapia gênica e os produtos naturais têm sido os caminhos escolhidos para a obtenção de novas moléculas. As florestas brasileiras estão entre os principais celeiros de biodiversidade, grande parte não estudada do ponto de vista fitoquímico e farmacológico. Isso implica em grandes possibilidades de identificação de novos fármacos, uma vez que a riqueza da biodiversidade biológica pode ser refletida na riqueza da biodiversidade química. Trinta e oito extratos provenientes de espécies de Apocynaceae foram submetidos a um estudo de triagem farmacológica antiviral, antimicrobiana e citotoxicidade, in vitro...