Enhanced Extraction and Improved Anticancer Activity of Neem (Azadirachta indica) Leaves by Electroporation Technique

Abstract

Plant-based medicines have been a part of primary healthcare since time immemorial. Natural products have received increasing attention to treat several regenerative diseases due to their availability and fewer side effects than conventional drugs. Towards this, Neem, commonly known as ‘Divine Life-giving tree’, has been investigated for its efficiency against MCF7, breast cancer cell lines. Ethanolic neem extracts were analysed for qualitative phytochemical screening tests, spectral analysis, antioxidant activity, and total phenol contents. In addition, to enhance the recovery of secondary metabolites from the plant extracts, electroporation (EP) technique is used. The effect of EP was studied by comparing with untreated extracts, which exhibits antioxidant activity (∼96% increase) and total phenol contents (∼12.51% increase) than untreated extracts. This indicates that electroporated extract (EE) exhibited higher antioxidant and phenolic activity than other extracts. Furthermore, different concentrations of untreated and electroporated neem extracts were used to study the anti-cancer activity. To enhance the uptake of extracts against cell membranes, electrical pulses of EP1 = 1200 V/cm, 100 s, 8 pulses and, EP2 = 500 V/cm, 20 ms, 8 pulses were used. The results indicate cell viabilities of 35% with untreated extract only, 5.6% with EE, 3.17%, and 2.49% with EP1 + EE extract and EP2 + EE extract, respectively, indicating the potential of the synergy of electrical pulses + EE. The viabilities were lowered by 5–6 times after 72 h. This treatment is more appropriate to achieve maximum cell death, thereby reducing the side effects of conventional drugs in treating breast cancer.

Keywords:

• Antioxidants
• Anticancer activity
• Azadirachta indica (Neem)
• Electroporation
• Phenols
• Spectral analysis

ACKNOWLEDGEMENT

We are very grateful to Dr M. Rajmohan, Professor and S. Hariharan, Research Scholar, Department of Industrial Engineering, CEG, Anna University for their valuable help in performing statistical analysis. We would like to thank Dr T. M. Sridhar, Head, Department of Analytical Chemistry, Madras University for extending their laboratory to perform phytochemical experiments. This work was supported by Anna University, Tamilnadu, India, under Anna Centenary Research Fellowship.

Additional information

Notes on contributors

S. Poompavai

S Poompavai received the BE degree in electrical and electronics engineering from Prince Shri Venkateshwara Padmavathy Engineering College, Anna University in 2013. She received her ME degree in high voltage engineering from the College of Engineering, Guindy, Anna University, in 2015, and at present she is a research student in the Division of High Voltage Engineering, Anna University, and Chennai, India. She has received Anna Centenary Research Fellowship award. Her research interests include application of pulsed electric fields to cancer, modelling of breast cancer, enhancing the extraction of bioactive compounds, study of effectiveness of natural herbal sources as an alternative chemotherapeutic drug.

V. Gowri Sree

V Gowri Sree received her doctorate in high voltage engineering in 2008 from the College of Engineering, Guindy, Anna University, India, where she is presently associate professor with over 25 years of teaching experience. She has contributed a chapter to the book, titled, “Electroporation-based Therapies for Cancer: From Basics to Clinical Applications” (Woodhead Publishing, 2014). Her current research topics are application of high voltage engineering for cancer treatment and enhanced bioactive compound extraction. Email: [email protected]

B. RamSugitha

B RamSugitha received BE in electrical and electronics engineering from Jerusalem College of Engineering, Anna University in 2016. She received her ME in high voltage engineering, College of Engineering, Anna University in 2019. Her research interests include pulsed electric field applications in biotechnology and cancer therapy. Email: [email protected]