Trypsin Inhibitors from Cajanus cajan and Phaseolus limensis Possess Antioxidant, Anti-Inflammatory, and Antibacterial Activity

ABSTRACT

Protease inhibitors are one of the most promising and investigated subjects for their role in pharmacognostic and pharmacological studies. This study aimed to investigate antioxidant, anti-inflammatory, and antimicrobial activities of trypsin inhibitors (TIs) from two plant sources (Cajanus cajan and Phaseolus limensis). TI was purified from C. cajan (PUSA-992) by ammonium sulfate precipitation followed by ion exchange chromatography. TI from Phaseolus limensis (lima bean trypsin inhibitor; LBTI) was procured from Sigma-Aldrich, St. Louis, Missouri, United States. The antioxidant activity was analyzed by ferric ion reducing antioxidant power (FRAP) and 2,2-diphenyl-1-picrylhydrazyl (DPPH). The anti-inflammatory property of TIs was determined by inhibition of albumin denaturation assay. Ascorbic acid and aspirin were used as standards for antioxidant and anti-inflammatory assays, respectively. These TIs were tested against various bacterial and fungal strains. The TIs showed DPPH radical–scavenging activity in a concentration-dependent manner with IC₅₀ values comparable to ascorbic acid. The FRAP values were also observed comparable to ascorbic acid and followed the trend of dose-dependent manner. The half maximal inhibitory concentration (IC₅₀) values of CCTI and LBTI in anti-inflammatory test showed that LBTI is more potent than CCTI. The TIs showed potent antibacterial activity, but apparently no action against fungi. This study has reported the biological properties of CCTI and LBTI for the first time. The results show that TIs possess the ability to inhibit diseases caused by oxidative stress, inflammation, and bacterial infestation.

KEYWORDS:

• antimicrobial
• antioxidant
• Cajanus cajan
• enzyme
• food property
• functional foods
• Phaseolus limensis
• trypsin inhibitor

Acknowledgment

The authors are thankful to Central Instrumentation Facility, Department of Biotechnology, Jamia Millia Islamia, India, for allowing the access to instruments for the research work.

Declaration of interest

The authors declare no conflicts of interest. The authors alone are responsible for the content and writing of the article.

About the authors

Tooba Naz Shamsi, MSc, PhD scholar, Department of Biotechnology, Jamia Millia Islamia, New Delhi, India.

Romana Parveen, MSc, PhD scholar, Department of Biotechnology, Jamia Millia Islamia, New Delhi, India.

Sumbul Afreen, MSc, PhD scholar, Department of Biosciences, Jamia Millia Islamia, New Delhi, India.

Mudasser Azam, MSc, PhD scholar, Department of Biosciences, Jamia Millia Islamia, New Delhi, India.

Yamini Sharma, MSc, PhD scholar, Department of Biosciences, Jamia Millia Islamia, New Delhi, India.

Priyankar Sen, PhD, Assistant Professor, Centre for Bio Separation Technology (CBST), VIT University, Vellore, India.

Qazi Mohd Rizwanul Haque, PhD, Professor, Department of Biosciences, Jamia Millia Islamia, New Delhi, India.

Tasneem Fatma, PhD, Professor, Department of Biosciences, Jamia Millia Islamia, New Delhi, India.

Nikhat Manzoor, PhD, Associate Professor, Department of Biosciences, Jamia Millia Islamia, New Delhi, India.

Sadaf Fatima, PhD, Assistant Professor, Department of Biotechnology, Jamia Millia Islamia, New Delhi, India.