en Biotechnology Biotechnology پژوهشي Orginal research papers <span style="font-size:11pt"><span style="line-height:120%"><span style="unicode-bidi:embed"><span style="font-family:Calibri,sans-serif"><span lang="EN" style="font-size:12.0pt"><span style="line-height:120%"><span new="" roman="" style="font-family:" times=""><span style="color:black">Acid-soluble collagen could be isolated from fish skin using acetic acid. In recent years, much attention has been paid to collagen from marine sources, mainly arising from the fact that </span></span></span></span><span style="font-size:12.0pt"><span style="line-height:120%"><span new="" roman="" style="font-family:" times=""><span style="color:black">there is</span></span></span></span><span lang="EN" style="font-size:12.0pt"><span style="line-height:120%"><span new="" roman="" style="font-family:" times=""><span style="color:black"> no risk of contagious diseases. Moreover, by processing the fish, significant amounts of waste materials are produced which can be considered as a substitute for these collagen sources. <i>Thunnus tonggol</i> skin collagen was extracted by acid and base methods and evaluated by SDS-PAGE, FTIR and UV spectrophotometry and amino acid composition analysis.</span></span></span></span><span style="font-size:12.0pt"><span style="line-height:120%"><span new="" roman="" style="font-family:" times=""><span style="color:black"> To determine biocompatibility, growth, and proliferation</span></span></span></span> <span style="font-size:12.0pt"><span style="line-height:120%"><span new="" roman="" style="font-family:" times=""><span style="color:black">of extracted collagen, MTT and H&E staining methods were used. </span></span></span></span><span lang="EN" style="font-size:12.0pt"><span style="line-height:120%"><span new="" roman="" style="font-family:" times=""><span style="color:black">The results, predicated on SDS-PAGE and amino acid analysis, demonstrated that the fish skin collagen was of type I consisting of two &alpha; chains (&alpha;1 and &alpha;2) with molecular weight of 135 kDa and mass fraction of &beta;. FTIR analysis also revealed helical compositions of both collagens, and UV spectrophotometry in <i>T. tonggol</i> skin collagen indicated a maximum absorption of 235 nm. The amount of collagen extracted from <a name="_Hlk82196927"><i>T. tonggol</i></a> skin turned out to be 17.3% dry weight. Analysis of extracted collagen amino acids from the mentioned fish showed that glycine was the predominant amino acid. </span></span></span></span><span lang="EN" style="font-size:12.0pt"><span style="line-height:120%"><span new="" roman="" style="font-family:" times=""><span style="color:black">Human fibroblast culture presented a superior growth and good biocompatibility on extracted collagen. So, this type of collagen could be used in tissue engineering as a proper scaffold.</span></span></span></span><span style="font-size:12.0pt"><span style="line-height:120%"><span new="" roman="" style="font-family:" times=""><span style="color:black"></span></span></span></span></span></span></span></span> Collagen, Fish skin, Amino acid composition, Thunnus tonggol 568 589 http://jifro.ir/browse.php?a_code=A-10-4277-2&slc_lang=en&sid=1 M.H. Samiei mh.samiei@stu.ssu.ac.ir 100319475328460045577 100319475328460045577 No Department of Natural Resources and Environment, Science and Research Branch, Islamic Azad University, Tehran, Iran S. Jamili Shahlajamili45@yahoo.com 100319475328460045578 100319475328460045578 Yes Iranian Fisheries Science Research Institute (IFSRI), Agricultural Research, Education and Extension Organization (AREEO), Tehran, Iran H. Nikukar habibnik@ssu.ac.ir 100319475328460045579 100319475328460045579 No Medical Nanotechnology and Tissue Engineering Research Center, Yazd Reproductive Sciences Institute, Shahid Sadoughi University of Medical Sciences, Yazd, Iran V. Razban razban_vahid@yahoo.com 100319475328460045580 100319475328460045580 No Department of Molecular Medicine, School of Advanced Medical Sciences and Technologies, Shiraz University of Medical Sciences, Shiraz, Iran