Opportunities for cleaner leather processing based on protease enzyme: Current evidence from an advanced bibliometric analysis

The leather industry is the fastest -growing sector globally and is present in footwear, clothing and automotive leather. The use of enzymatic processes that potentially produce sector production is an alternative that has already been validated as an ecologically more favourable mechanism. This review aims to carry out an advanced bibliometric analysis of studies and research advances on using the protease enzyme in leather processing. The Web of Science platform refined 65 publications related to the area from 2010 to 2022. Prominent researchers, countries, journals and institutions were identified. Central research on the topic is concentrated in India, Tunisia, Algeria, China and Brazil, countries that produce the most in the area. The keyword analysis identified five clusters associated with new applicable methodologies that contribute to economic efficiency in the leather industries. Alkaline proteases of bacterial origin are the most prominent in biotechnological processes, the alkaline serine protease being the most important. Species of the genus Bacillus were the most explored, emphasizing Bacillus Subtilis and Bacillus Cereus. The keyword "bacillus" is the second word that appears most in the articles analyzed (23.9 % in 39 publications), the first keyword is "dehairing" (31.9 % in 52 publications), which is the process that most applies to alkaline products and protease enzymes. The industry has a significant interest in the use of protease enzymes. Future studies should focus on new favourable processes for protease applications, aiming to improve the production of cleaner leather.