摘要
黄斑蓝子鱼(Siganus oramin)具有天然抗刺激隐核虫(Cryptocaryon irritans)能力,并从其血清中分离纯化了一种抗虫蛋白。以黄斑蓝子鱼皮肤黏液为对象,研究了其对刺激隐核虫(C.irritans)、多子小瓜虫(Ichthyophthirius multifiliis)、布氏锥虫(Trypanosoma brucei brucei)及一些病原菌的杀灭和抑制效果。结果显示:黄斑蓝子鱼黏液对刺激隐核虫、多子小瓜虫和布氏锥虫均具有明显的杀虫效果,黏液蛋白对3种寄生虫的最低杀寄生虫浓度(Minimum Parasiticidal Concentration,MPC)分别为4.0、5.0和3.0 mg/mL。显微镜观察发现,刺激隐核虫和多子小瓜虫的幼虫在经过黄斑蓝子鱼黏液作用后,均出现纤毛脱落、虫体肿胀、外膜破裂和内容物泄漏等现象。黏液抑菌活性实验结果表明,除大肠杆菌(Escherichia coli)外,黄斑蓝子鱼皮肤黏液对金黄色葡萄球菌(Staphylococcus aureus)、霍乱弧菌(Vibrio cholerae)、海豚链球菌(Streptococcus iniae)、温和气单胞菌(Aeromonas sobria)、溶藻弧菌(Vibrio alginolyticus)、副溶血弧菌(Vibrio Parahaemolyticus)、星形诺卡氏菌(Nocadia asteroides)和美人鱼发光杆菌杀鱼亚种(Photobacterium damselae subsp.)皆有明显的抑菌效果。在最低抑菌浓度(Minimum Inhibitory Concentration,MIC)测定中,黄斑蓝子鱼黏液对金黄色葡萄球菌、霍乱弧菌、海豚链球菌、溶藻弧菌、温和气单胞菌和副溶血弧菌的MIC分别为0.16、0.16、0.08、0.63、0.63和0.63 mg/mL。黄斑蓝子鱼皮肤黏液对小麦赤霉菌(Gibberella saubinetii)和黑曲霉菌(Aspergillus niger)没有明显抑菌作用。
Cryptocaryon irritans,an important marine ciliate protozoan that causes a disease known as ＂marine white spot disease＂,has already become one of the most harmful parasites in Chinese marine aquaculture industry.Previous studies indicated that the rabbitfish（Siganus oramin） showed low susceptibility to C.irritans infections,and the serum of rabbitfish had killing effect against C.irritans.Practically,the skin mucus of fish has been considered to be the first defense against infections caused by various pathogens.Whether the skin mucus of rabbitfish has the same parasiticidal activity is the main research purpose of this paper.In this study,we compared the antiparasitic and antibacterial activities of skin mucus from S.oramin,Epinephelus coioides,Sciaemops ocellatus,Plectorhinchus cinctus and Trachinotus ovatus.The parasite-killing effects of skin mucus were tested by immobilization assay for three species of parasites,C.irritans,I.multifiliis,and T.brucei brucei.The antimicrobial properties of skin mucus were determined using the agar diffusion method and the minimum inhibitory concentration for six species of bacteria（Staphylococcus aureus,Bacillus subtilis,Streptococcus iniae,Escherichia coli,Vibrio cholera,Aeromonas sobria,Edwardsiella tarda,Photobacterium damselae subsp.and Vibrio alginolyticus） and two species of fungi（Aspergillus niger and Gibberella saubinetii） were also examined.We found that compared with the skin mucus isolated from E.coioides,S.ocellatus,P.cinctus and T.ovatus,the rabbitfish skin mucus was lethal to C.irritans,I.multifiliis,and T.brucei brucei.The minimum parasiticidal concentration（MPC） of rabittfish skin mucus for C.irritans,I.multifiliis and T.brucei brucei were 4.0,5.0,and 3.0 mg/mL,respectively.After the theronts of C.irritans and I.multifiliis were co-incubated with the skin mucus of rabbitfish,we observed the cilia falling off,body swelling,outer membrane rupture and contents release under a electron microscope.In addition,the results of bactericidal activity showed that the skin mucus of rabbitfish could inhibit the growth of S.aureus,V.cholera,S.iniae,A.sobria,V.alginolyticus,V.Parahaemolyticus,N.asteroids and P.damselae subsp.The minimum inhibitory concentration（MIC） of rabbitfish skin mucus for S.aureus,V.cholera,S.iniae,V.alginolyticus,A.sobria and V.Parahaemolyticus were 0.16,0.16,0.08,0.63,0.63 and 0.63 mg/mL,respectively.However,the skin mucus of rabbitfish had no effect on the growth of two tested fungi species-G.saubinetii and A.niger.This result suggested that the skin mucus of rabbitfish played an important role in the innate host defensive mechanism to combat against C.irritan and other pathogenic organisms.Base on our observation,further studies on purification and identification of these skin-mucus antiparasitic factors need to be carried out.This type of investigation will provide a new method for controlling the C.irritans.Therefore,we expect that our ongoing work will have great significance to the studies on the innate immunity of fish and the biocontrol of the parasites.
出处
《水生生物学报》
CAS
CSCD
北大核心
2013年第2期243-251,共9页
Acta Hydrobiologica Sinica
基金
国家自然科学基金(31172443)
广东省自然科学基金(S2012010009148)资助
关键词
黄斑蓝子鱼
黏液
刺激隐核虫
抗寄生虫
抗菌
Siganus oramin
Mucus
Cryptocaryon irritans
Parasiticidal
Bactericidal
