Macroscopic and microscopic morphological characteristics of gelatinous egg masses (egg veils) of yellow goosefish Lophius litulon (Lophiiformes; Lophiidae).

We recorded the morphological characteristics and effect of preservation methods on the structure of the egg veils of Lophius litulon found in field investigations. The egg veils were characterized as translucent sheet-shape with parallel opaque creases spaced approximately 2 cm apart. The egg veils were found to be composed of pentagonal or hexagonal chambers with rounded corners arranged in one layer, and each chamber enveloped one to three embryos. Cryopreservation is recommended to prevent structural changes in the egg veil rather than ethanol solution and neutral buffered formalin solution.

Distinct gut microbial communities and functional predictions in divergent ophiuroid species: host differentiation, ecological niches, and adaptation to cold-water habitats.

IMPORTANCE: Gastrointestinal microorganisms are critical to the survival and adaptation of hosts, and there are few studies on the differences and functions of gastrointestinal microbes in widely distributed species. This study investigated the gut microbes of two ophiuroid species (Ophiura sarsii and its subspecies O. sarsii vadicola) in cold-water habitats of the Northern Pacific Ocean. The results showed that a combination of host and environmental factors shapes the intestinal microbiota of ophiuroids. There was a high similarity in microbial communities between the two groups living in different regions, which may be related to their similar ecological niches. These microorganisms played a vital role in the ecological success of ophiuroids as the foundation for their adaptation to cold-water environments. This study revealed the complex relationship between hosts and their gut microbes, providing insights into the role they play in the adaptation and survival of marine species.

Rapid preparation of fluorescent 9-anthrylmethyl esters for fatty acid analysis of small amount of triacylglycerols.

This paper proposes a one-step method for preparation of fluorescent 9-anthrylmethyl esters from triacylglycerols (TAG) ranging in amount from 0.1 to 5 microg. It involves base-catalyzed transesterification using potassium 9-anthracenemethoxide, prepared by proton exchange between 9-anthracenemethanol and potassium tert-butoxide. Transesterification for 10 min at room temperature gave the fatty acid 9-anthrylmethyl esters in nearly maximal yields (82-85%). The products could be analyzed by reversed-phase HPLC without purification. Excellent linear relationships were observed for standard curves of 10-250 pmol of TAG standards (16:0, 19:0, 18:2 and 22:6), and differences in the slopes were less than 5% among the standards. Almost consistent compositions of the esters were observed for the products formed from 0.5 to 5 microg or less of fish oils TAG, and they were similar to those obtained by HPLC of ordinary multi-step synthesis products and by GLC of methyl esters. The present method is a great improvement of derivatization time, and is powerful for fatty acid analysis of small amounts of natural TAG.