Holothuria

About: Holothuria is a research topic. Over the lifetime, 362 publications have been published within this topic receiving 4982 citations.

B:Genus Holothuria an imminent source of diverse chemical entities: A review

Abstract: Nature is a valuable source for many medicines in use. About 30 per cent of the world's drugs are either natural products or their biologically active derivatives. Natural products display a wide range of chemical structures that even are unapproachable by highly formulated synthetic principles. Compared to the terrestrial, marine organisms have provided the widest diversity; thirty-four of the thirty-six phyla of life exist. One of the most important diverse families of sea cucumbers is the Holothuriidae family, which exist in oceans and shallow waters as well. This family comprises five genera. Among them, genus Holothuria which is the most predominant one and represented in Egypt by eight species. Phytochemical investigation of sea cucumbers belonging to genus Holothuria has led to the isolation and identification of numerous chemical compounds of different classes. The current review demonstrated that genus Holothuria is a rich source of cerebrosides, saponins, fatty acids, amino acids and phenolics.

Caracterización de los ácidos grasos y actividad antimicrobiana del extracto en metanol de Holothuria princeps (Holothuriida: Holothuriidae)

Abstract: Introduction: In recent decades, studies related to the search and characterization of bioactive molecules in marine organisms have increased exponentially, demonstrating the enormous wealth of secondary metabolites of diverse structural composition that cannot be found in organisms present in the terrestrial environment. A significant number of the new marine natural compounds discovered have contributed to solving some of the problems of humanity, mainly those related to human health. Objective: The purpose of this research is to evaluate the bactericidal and fungicidal activities of the methanolic extract of sea cucumber Holothuria princeps collect from the bay of Cispata in the Colombian Caribbean, in addition to chemically identifying its fatty acids. Methods: A methanolic extraction was performed from the collected biological material, by the cold maceration method. The extract obtained was fractionated using chromatographic techniques and the fatty acids were obtained, which were derivatized and identified by means of gas chromatography in coupling with mass spectrometry. The antibacterial and antifungal activities of the methanolic extract of Holothuria princeps was performed through the microdilution method against reference strains and clinical isolates. Results: We found 16 fatty acids present in Holothuria princeps according to the analysis of their mass spectra. Antibacterial activity showed that Enterococcus faecalis was the most susceptible to the extract at low concentrations, while Pseudomonas aeruginosa was the highest at the higher concentrations. In antifungal treatment, the fungus with the highest inhibition was the clinical isolate of Candida albicans (blood sample). Conclusions: Taking into account previous studies in the genus Holothuria, it is considered that the environment plays a fundamental role in the presence and diversity of fatty acids. The evaluation of the antibacterial activity against reference strains of Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, Klebsiella pneumoniae and Enterococcus faecalis demonstrated the existence of a considerable effect in the reduction of bacterial growth by the extracts applied, mainly at low concentrations (less than 1 000 ppm). On the other hand, the antifungal activity against the reference strain of Candida albicans and the clinical isolates of Candida albicans (blood sample) and Candida krusei (catheter sample), the extract showed that the best results were presented at higher concentrations (above 1 500 ppm).

First record of asexual reproduction of Holothuria (Mertensiothuria) hilla in a fringing reef at Reunion Island, western Indian Ocean

Abstract: Around 10 species of holothurians are known to be naturally fissiparous, and several belong to the genus Holothuria (H. atra, H. leucospilota, H. edulis and H. parvula). This note reports on the observation of asexual reproduction in Holothuria hilla at Reunion. Evidence of natural fissiparity had been previously observed in this species in June 2001, with an anterior specimen regenerating the posterior end (weight 22 g) and a posterior one regenerating with an anterior end (weight 32 g). Only one specimen of the species was observed at this date.

PHYLOGENY OF Holothuria leucospilota (ECHINODERMATA: HOLOTHUROIDEA) AS INFERRED FROM CYTOCHROME C OXIDASE I mtDNA GENE SEQUENCES

Abstract: This study aimed to generate the genetic profile of Holothuria (Mertensiothuria) leucospilota (Brandt 1835) from Intan Besar Island, Langkawi, Kedah Darul Aman, Malaysia and then to determine the phylogenetic relationship between H. leucospilota and other members of genus Holothuria available in the GenBank using partial sequences of cytochrome c oxidase I (COI) mitochondrial DNA (mtDNA) gene. In this study, tree topologies of neighbour joining, maximum parsimony and maximum likelihood show that H. leucospilota has its own monophyletic clade clearly distinct from the other species and it is genetically closer to Holothuria (Acanthotrapeza) coluber Semper 1868.

The Reproductive Cycle of Holothuria Cucumaria frondosa of the Barents Sea

Abstract: The study considers the morphological features of the gonad structure and the seasonal changes in the reproductive activity of the gonads of holothuria Cucumaria frondosa of the Barents Sea. The sex of individuals can be identified using morphometric analysis with the average mass of gonads of 1.63 g, with the average mass of the skin-muscle sac of 53.00 g and the length of 80.00-83.00 mm whereas the diameter of the genital tubes is not less than 0.50 mm. The spawning of cucumaria, producing plankton progeny, occurs from March to May, but the spawning period can be shifted, since the beginning of the spawning period is associated with the seasonal increase of the surface water temperature and the intensive phytoplankton blooming. The character of spawning is intermittent. Individual fertility is low, in individuals with the average mass of SMS 150.00-200.00 g ranged from 9 to 32 thousand cells.