African Journal of
Biotechnology

  • Abbreviation: Afr. J. Biotechnol.
  • Language: English
  • ISSN: 1684-5315
  • DOI: 10.5897/AJB
  • Start Year: 2002
  • Published Articles: 12291

Full Length Research Paper

Evaluation of the physical properties of leathers tanned with Plectranthus barbatus Andrews extracts

Dennis Kimaiga Obiero
  • Dennis Kimaiga Obiero
  • Department of Public Health Pharmacology and Toxicology, Faculty of Veterinary Medicine, College of Agriculture and Veterinary Sciences, University of Nairobi, Nairobi, Kenya.
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Jackson Nyarong̛i Ombui
  • Jackson Nyarong̛i Ombui
  • Department of Public Health Pharmacology and Toxicology, Faculty of Veterinary Medicine, College of Agriculture and Veterinary Sciences, University of Nairobi, Nairobi, Kenya.
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Arthur Steven Onyuka
  • Arthur Steven Onyuka
  • Department of Research Technology and Innovation, Leather Division, Kenya Industrial Research and Development Institute, Nairobi, Kenya.
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Alvin Asava Sasia
  • Alvin Asava Sasia
  • Department of Research Technology and Innovation, Leather Division, Kenya Industrial Research and Development Institute, Nairobi, Kenya.
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  •  Received: 16 April 2016
  •  Accepted: 26 October 2016
  •  Published: 31 March 2020

Abstract

This study was designed to assess the potential use of Plectranthus barbatus Andrews, a plant growing locally in Kenya as a vegetable tanning agent. The aim was a deliberate attempt to adopt green chemistry and provide cheap locally available eco-friendly tanning materials. Anova statistical test (α<0.05) was used to compare the physical properties of leather tanned with three kinds of liquors made from the plant and the following mean values were recorded: Shrinkage temperature of 61.5 to 67.5°C; Grain crack range of 7.5 to 8.7 mm; Grain burst range of 7.9 to 9.1 mm; tear strength of 41.8 to 78.2 N with percentage (%) elongation of 68.4 to 75.9%; tensile strength of 17.6 to 40.8 N/mm2 with % elongation of 15.9 to 42.2% and thickness of 0.7 to 1.2 mm. The study concluded that P. barbatus Andrews leaves have adequate tannin content of hydrolysable type required for tanning. Furthermore, the brown colour of the leather produced is unlikely to undergo saddening as usually observed in Mimosa because of relative stability of hydrolysable tannins to light.

 

Key words: Shrinkage temperature, distension, pelts, tannins, vegetable tanning, pyrogallol.