| Tetrodotoxin(TTX), known as Spheroidine and Fugu poison, is one of the most potent non-protein neurotoxins extracted form the ovaries and livers of the puffer fish. It can block sodium channels and thus inhibits the propagation of action potentials. TTX was widely used as an important pharmacological reagent for neurobiological research. A recent study showed that TTX may be one of the most promising analgesic, detoxification agent and local anesthetic in the future which is currently under phase II clinic trials. All these will increase the application of TTX. Currently, TTX is purified from ovaries and livers of puffer fish and the yield is limited. Isolation of TTX-producing bacteria will make it possible to produce large amount of TTX in vitro without destroying the puffer fish resource.The origin of TTX is one of the most controversial topics. TTX was originally discovered and isolated from certain species of puffer fish. It has been known for many years that the toxicity of the ovaries and livers of puffer fish is more potent than that of other organs, but the farming puffer fish are non-toxic. For a long time, puffer fish was thought to produce and accumulate TTX within their body. However, TTX not only exist in puffer fish, but also in varies of animals. These bearing-TTX animals have one common point which is that they all have some kinds of TTX-producing microbe. In recent years, many TTX-producing microorganisms have been discovered. As a result, the theory on microorganismic source of TTX is advocated by more and more scholars.The aim of the present study was to isolate and identify of the intestinal bacteria from the Taikifugu oblongus's intestine, and clarify the intestinal bacteria flora of the Taikifugu oblongus. The bacterial production of TTX was achieved and detected by mouse bioassay and post column derivation HPLC(High Performance Liquid Chromatography). Our results demonstrated that (1) three strains bacteria existed in the Taikifugu oblongus's intestine; (2) based on 16S ribosomal DNA (rDNA) sequences, the bacteria were identified as Brachybacterium paraconglomeratum(HDC13), Bacillus megaterium(HDC35), Psychrobacter celer(HDC37);(3)the groups of (HDC13, HDC35)and (HDC13, HDC35, HDC37) also can produce TTX.In summary, the present study firstly indicated the intestinal bacteria flora and discovered the TTX-producing bacteria of the Taikifugu oblongus. The results will play an important role in the study of the origin of the tetrodotoxin (TTX). Crude oil, also known as petroleum , is a type of combustible organic mineral. It is an extremely complex mixture which is dominantly composed of hydrocarbons,such as paraffin hydrocarbon, olefin, cyclane and dutrex. Besides, the petroleum also contains sulfur-containing compounds, nitrogenous compounds, oxygen-containing compounds and a few of organometallics. Due to the different composition, the crude oil produced from the different oil field usually have different properties. Different types of petroleum , on the basis of the different properties, should be used diverse processing approaches for the appropriate products. Therefore, qualitative chemical analysis of the components of crude oil is very meaningful to the oil processing. Along with the frequently increasing occurence of the accidental oil spills in the marine environment, the identification of oil spills has become an important means of taking evidence and the identification of oil fingerprints is the primary technique for oil spill source identification. In addition, the ability of microorganisms to degrade petroleum hydrocarbons has been widely documented. Therefore, it's important for the biodegardation of oill spill to isolate the petroleum-degrading microorganisms.Firstly, the components of crude oil produced in Sheng Li Oil Field was analyzed qualitatively using gas chromatography-mass spectrometry ( GC-MS). Some indices, such as CPI, Cmax, and PPhr , were employed to analyze the fingerprints of the crude oil. 103 kinds of components were identified by the qualitative analysis, and the concentration of saturated paraffinic hydrocarbons were accounted for 89.864%. The analysis of the fingerprints indicated that the evolution degree of the crude oil produced in Sheng Li Oil Field is high and its type of source is good. Also, the sedimentary environments of the crude oil belongs to the marine and reducing condition. Secondly, three petroleum-degrading bacteria isolated from oil contaminated soil were identified by theirs 16s rDNA sequencing. Two strains belong to Acinetobacter sp., and the other one belongs to Pseudomonas sp..These strains were found to have the high ability of degrading the majority of petroleum hydrocarbon.
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