Effect of Blanching on the Protein Profile of Bitter Leaf (Vernonia amygdalina) Analyzed by SDS-PAGE

Authors

  • Fitri Widya Handayani Biotechnology Study Program, Faculty of Food Security, Universitas Negeri Surabaya, Jl. Prof.Dr.Moestopo No.4, Surabaya, Indonesia
  • Shinta Wulansari Biotechnology Study Program, Faculty of Food Security, Universitas Negeri Surabaya, Jl. Prof.Dr.Moestopo No.4, Surabaya, Indonesia

DOI:

https://doi.org/10.33394/hjkk.v14i3.20408

Keywords:

Vernonia amygdalina, Blanching, SDS-PAGE, Protein Profile, Polyphenol

Abstract

Blanching is widely employed as a pre-treatment for leafy vegetables to inactivate enzymes and preserve quality. However, its effect on protein integrity in polyphenol rich species remains inadequately characterized. This study evaluated the effect of blanching on the protein profile and protein content of bitter leaf (Vernonia amygdalina). Blanched and non-blanched leaves were extracted using a TCA-based protocol, and protein profiles were analyzed by SDS-PAGE, while protein content was determined by the Kjeldahl method in triplicate. SDS-PAGE revealed distinct protein bands only in blanched samples, whereas non-blanched samples showed no visible bands. Kjeldahl analysis indicated that non-blanched samples had slightly higher protein content (19.20 0.13%) than blanched samples (18.24 0.21%, p < 0.05). These findings suggest that blanching improves protein extractability and electrophoretic detectability, although it slightly reduces total Kjeldahl protein content. Combined qualitative and quantitative approaches are essential for accurate protein assessment in polyphenol-rich plant materials.

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Published

2026-06-30

How to Cite

Handayani, F. W., & Wulansari, S. (2026). Effect of Blanching on the Protein Profile of Bitter Leaf (Vernonia amygdalina) Analyzed by SDS-PAGE. Hydrogen: Jurnal Kependidikan Kimia, 14(3), 479–487. https://doi.org/10.33394/hjkk.v14i3.20408

Issue

Vol. 14 No. 3 (2026): June 2026

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Copyright (c) 2026 Fitri Widya Handayani, Shinta Wulansari

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