Investigation of lipolytic activity of the red king crab hepatopancreas homogenate by NMR spectroscopy

The digestive gland of craboids (hepatopancreas) is rich in a huge number of various enzymes (collagenases, nucleases, hyaluronidases, proteases), which are well studied at the moment. However, little is known about crustacean lipases. In this work, using 1H NMR spectroscopy, it was found that the hepatopancreas homogenate of the red king crab Paralithodes camtschaticus demonstrates high lipolytic activity against triacetin in a wide pH range and shows moderate activity against the caprylic/capric triglyceride emulsion. Under the action of the hepatopancreas homogenate, triacylglycerols are converted into 1,2-diacylglycerol, and then into 2-monoacylglycerol and 1-monoacylglycerol. The 1-monoacylglycerol predominates in the reaction products. The use of NMR spectroscopy makes it possible to quickly detect hydrolysis products and evaluate the reaction direction.

Metatranscriptomic Analysis Reveals an Imbalance of Hepatopancreatic Flora of Chinese Mitten Crab Eriocheir sinensis with Hepatopancreatic Necrosis Disease

Hepatopancreas necrosis disease (HPND) of the Chinese mitten crab Eriocheir sinensis causes huge economic loss in China. However, the pathogenic factors and pathogenesis are still a matter of dissension. To search for potential pathogens, the hepatopancreatic flora of diseased crabs with mild symptoms, diseased crabs with severe symptoms, and crabs without visible symptoms were investigated using metatranscriptomics sequencing. The prevalence of Absidia glauca and Candidatus Synechococcus spongiarum decreased, whereas the prevalence of Spiroplasma eriocheiris increased in the hepatopancreatic flora of crabs with HPND. Homologous sequences of 34 viral species and 4 Microsporidian species were found in the crab hepatopancreas without any significant differences between crabs with and without HPND. Moreover, DEGs in the hepatopancreatic flora between crabs with severe symptoms and without visible symptoms were enriched in the ribosome, retinol metabolism, metabolism of xenobiotics by cytochrome P450, drug metabolism—cytochrome P450, biosynthesis of unsaturated fatty acids, and other glycan degradation. Moreover, the relative abundance of functions of DEDs in the hepatopancreatic flora changed with the pathogenesis process. These results suggested that imbalance of hepatopancreatic flora was associated with crab HPND. The identified DEGs were perhaps involved in the pathological mechanism of HPND; nonetheless, HPND did not occur due to virus or microsporidia infection.

Prospects of Red King Crab Hepatopancreas Processing: Fundamental and Applied Biochemistry

Since the early 1980s, a large number of studies on enzymes from the red king crab hepatopancreas were conducted. They have been relevant both from a fundamental point of view in terms of studying the enzymes of marine organisms and in terms of rational natural resource management aimed to obtain new valuable products from the processing of crab fishing waste. Most of these works were performed by Russian scientists due to the area and amount of waste of red king crab processing in Russia (or the Soviet Union). However, the close phylogenetic kinship and the similar ecological niches of commercial crab species and the production scale of the catch provide the bases for the successful transfer of experience in the processing of the red king crab hepatopancreas to other commercial crab species caught worldwide. This review describes the value of recycled commercial crab species, discusses processing problems, and suggests possible solutions for these issues. The main emphasis is made on hepatopancreatic enzymes as the most salubrious products of red king crab waste processing.

Prospects of Red King Crab Hepatopancreas Processing: Fundamental and Applied Biochemistry

Since the early 1980s, a large number of research works on enzymes from the red king crab hepatopancreas have been conducted. These studies have been relevant both from a fundamental point of view for studying the enzymes of marine organisms and in terms of the rational management of nature to obtain new and valuable products from the processing of crab fishing waste. Most of these works were performed by Russian scientists due to the area and amount of waste of red king crab processing in Russia (or the Soviet Union). However, the close phylogenetic kinship and the similar ecological niches of commercial crab species and the production scale of the catch provide the bases for the successful transfer of experience in the processing of red king crab hepatopancreas to other commercial crab species mined worldwide. This review describes the value of recycled commercial crab species, discusses processing problems, and suggests possible solutions to these problems. The main emphasis is placed on the enzymes of the hepatopancreas as the most highly salubrious product of waste processed from red king crab fishing.

The effect of hepatopancreas homogenate of the Red king crab on HA-based filler

In this study, several methods were used to analyze the hydrolysis of hyaluronic acid (HA)-based cosmetic fillers by the hepatopancreas homogenate of the Red king crab. The results show that the homogenate and commercially available hyaluronidases have similar hydrolysis activities on the fillers. Atomic force microscopy images reveal that the HA fillers consist mainly of spherical-like particles, which are converted into filamentous structures as a result of hydrolysis by the Red king crab hepatopancreas homogenate. Turbidimetric analysis of the hydrolysis process shows that HA aggregation with acidic albumin exhibits a bell-shaped dependence on reaction time. Analysis of the hydrolysis process by nuclear magnetic resonance shows that HA degradation lasts several days. The maximum rate of the reaction is detected in the 1st h of incubation. The data confirm that the purified homogenate of the Red king crab hepatopancreas exerts hyaluronidase activity on HA-based cosmetic fillers; therefore, it may be considered as a potential therapeutic agent for treating filler complications.

Perspectives on the Use of Hyaluronidase from the Red King Crab Hepatopancreas in Treating Filler Complications: In Vitro Investigations

This study focused on hydrolysis of cosmetic fillers hyaluronic acid (HA) and kinetics of the HA hydrolysis using the homogenate of the red king crab hepatopancreas. Turbidimetric analysis of the reaction mixture revealed a bell-shaped time dependence of aggregation formation. It was shown that the obtained homogenate has the similar activity to the commercially available hyaluronidase. The atomic force microscopy (AFM) examination found that the HA fillers were represented by spherical-like structures. These structures were destroyed under the action of the homogenate of the red king crab hepatopancreas. NMR of the reaction mixture showed that HA degradation lasts for some days, but a maximum rate of the reaction is detected in the first hours of incubation. The preparation with hyaluronidase activity obtained from the red king crab hepatopancreas could be used as potentially safe product for treating filler complications.

Perspectives on the Use of Hyaluronidase from the Red King Crab Hepatopancreas in Treating Filler Complications: In Vitro Investigations

The kinetics of the hydrolysis of hyaluronic acid (HA) of cosmetic fillers using thehomogenate of the red king crab hepatopancreas was studied for the first time. Turbidimetricanalysis of the reaction mixture revealed a bell–shaped time dependence of aggregation formation. The HA fillers were examined by atomic force microscopy (AFM) and it was found that they wererepresented by spherical–like structures. These structures were disrupted under the action of thehomogenate of the red king crab hepatopancreas. It was shown that the prepared homogenate hasthe activity which is similar to that observed in the commercially available hyaluronidase products.The preparation with hyaluronidase activity obtained from the red king crab hepatopancreas couldbe used as potentially safe product for treating filler complications.