There is a growing interest in the utilization of animal by-products and wastes. Plant-derived enzymes could play a vital role in collagen extraction from tannery-trimming wastes. Here, the ficin enzyme from fig leaves was used for collagen extraction and compared with conventional acetic acid and pepsin extraction methods, aiming to assess the efficiency and purity of collagen extracted using this plant-based enzyme approach relative to the organic solvents and animal-derived enzymes. The extracted collagen was identified as type I collagen. Response surface methodology analysis revealed that the ficin enzyme-soluble collagen yielded 15.28 % at a hydrolysis time of 39.27 h, a ficin enzyme dose of 5.54 %, and a mixing ratio of 15.87, higher than the acetic acid-soluble collagen yield of 9.52 % and pepsin enzyme-soluble collagen yield of 14.56 %. Ficin enzyme-soluble collagen exhibited better integrity of the triple helical structure with fewer proteinaceous impurities, though it showed poorer thermal stability. Ultrasound treatment at 800 W for 30 min did not significantly disrupt the triple helical structure of collagen. The work aims to develop a green and sustainable method for extracting collagen from tannery-trimming wastes, offering a novel approach for the high-value conversion of animal by-products and agro-residues wastes.
This study established a high-efficiency fluorescence quenching approach for the in situ visualization and modeling of the spatial distribution of xylanase, β-glucosidase, and phosphatase activities in plant leaves under pollution stress (namely, the leaf zymography technique, LZT). In the LZT, a membrane saturated with an enzyme-specific fluorescent substrate on the leaf surface was incubated and the fluorescence image generated on the membrane under ultraviolet light was recorded. An image-based modeling method for restoring the morphological traits of the true image by reducing noise was developed to ensure the accurate estimation of enzyme activities. The LZT could simultaneously measure 48 samples within 2 h, with good reproducibility. The results obtained by the LZT were comparable to those obtained by a conventional biochemical analysis method and presented low-cost and convenient advantages. This paper explains the theoretical basis required to investigate the realistic application of the LZT for assessing ecotoxicity in large-scale monitoring.
危险品化学品经营许可证（带存储）