de Vasconcelos Jamile Maria Pereira Bastos Lira, de Araújo Neri Robson Coelho, de Barros Amanda Vieira, da Silva Carlos Eduardo Sales, Galindo Maria Cecília Ferreira, de Veras Bruno Oliveira, Bezerra Ranilson Souza, de Oliveira Maria Betânia Melo
Federal University of Pernambuco-UFPE Recife, Av. Prof. Moraes Rego, 1235 - Cidade Universitária, Recife, 50670 - 901, Pernambuco, Brazil.
Centro de Ciências Biológicas, Departamento de Bioquímica e Biofísica, Laboratório de Enzimologia, Federal University of Pernambuco, Cidade Universitária, Recife, 50670 - 420, Pernambuco, Brazil.
Appl Biochem Biotechnol. 2025 Apr 28. doi: 10.1007/s12010-025-05242-z.
The aim of the study was to extract and characterize collagen from solid untanned skin waste from the processing of leather in a Capra aegagrus tannery. Using pepsin (SPC), 37 g of collagen were obtained from 100 g of dry weight skin. Characterization took place using SDS-PAGE, FTIR and UV absorption techniques, identifying it as type I collagen. The ultraviolet (UV) absorption spectrum showed a peak at 238 nm. In the thermogram, the maximum transition temperature was 56º C. Using the electrophoresis technique, it was observed that SPC consists of band patterns formed by a γ chain, a β chain and two distinct α chains (α1 and α2). In the FTIR analysis, the collagen showed the absorption peaks for the amides, showing that the SPC extraction process maintained the integrity of the molecule. To observe the effect of NaCl concentration on the solubility of SPC, the collagen showed high solubility, up to a concentration of 2% NaCl. The solubility peak was observed at pH 4.0, with a sharp drop until pH 7.0, reaching its minimum point at pH 10. Scanning microscopy showed some irregular surfaces, cavities and fibrous structures, which may favor the application of collagen as a biomaterial. The zeta potential found the isoelectric point of collagen at pH = 6.61. These results indicate that the collagen obtained has a high level of structural integrity and can be applied as an alternative source, as well as adding value to a waste product that is often discarded in the environment.
本研究的目的是从一家捻角山羊皮革厂皮革加工过程中产生的未鞣制固体皮废料中提取胶原蛋白并对其进行表征。使用胃蛋白酶（SPC），从100克干重的皮肤中获得了37克胶原蛋白。采用SDS-PAGE、傅里叶变换红外光谱（FTIR）和紫外吸收技术进行表征，确定其为I型胶原蛋白。紫外吸收光谱在238纳米处有一个峰值。在热重曲线上，最大转变温度为56℃。使用电泳技术观察到，SPC由γ链、β链和两条不同的α链（α1和α2）形成的条带模式组成。在FTIR分析中，胶原蛋白显示出酰胺的吸收峰，表明SPC提取过程保持了分子的完整性。为了观察氯化钠浓度对SPC溶解度的影响，胶原蛋白在氯化钠浓度高达2%时表现出高溶解度。在pH 4.0时观察到溶解度峰值，直到pH 7.0时急剧下降，在pH 10时达到最低点。扫描显微镜显示出一些不规则表面、空洞和纤维结构，这可能有利于胶原蛋白作为生物材料的应用。ζ电位测定胶原蛋白的等电点为pH = 6.61。这些结果表明，所获得的胶原蛋白具有高度的结构完整性，可作为一种替代来源应用，同时为一种经常被丢弃在环境中的废品增加价值。
