Sequential injection-chemiluminescence evaluation of stigmasterol glucoside and luteolin via green synthesis of silver nanoparticles using biomass of plectranthus asirensis

ABSTRACT

The present study focused on the phytochemical chromatographic isolation of two chemical constituents, sterol and flavonoid (stigmasterol glucoside and luteolin) from Plectranthus asirensis. A novel, eco-friendly, and cost benefit, ultrasensitive sequential injection analysis chemiluminescence (SIA-CL) approach based on the enhanced catalytic activity of silver nanoparticles (AgNPs) was suggested to evaluate the isolated compounds. Silver nanoparticles were synthesized using the biomass of an ethanolic extract of aerial parts of P. asirensis as a reducing agent. Spectroscopic and microscopic characterization of the prepared AgNPs were performed, including UV-Vis spectrometry, XRD and FT-IR as well as TEM and SEM. UV-spectroscopic method detected the formed AgNPs at an absorbance wavelength of 420 nm. Furthermore, antioxidant activity of the isolated compounds was also determined using 1,1-Diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity protocol.

GRAPHICAL ABSTRACT

KEYWORDS:

• Plectranthus asirensis
• silver nanoparticles
• sequential injection analysis
• stigmasterol glucoside
• luteolin
• green chemistry
• chemiluminescence

Acknowledgments

This research project was supported by a grant from the “Research center of the female Scientific and Medical Colleges”, Deanship of Scientific Research, King Saud University.

Disclosure statement

No potential conflict of interest was reported by the authors.

Notes on contributors

Musarat Amina is an associate professor of Natural Product Chemistry at King Saud University, Riyadh, Saudi Arabia. She received her PhD and Master’s degree in Organic Chemistry from Aligarh Muslim Aligarh, India.

Nawal A. Alarfaj is a professor of Analytical Chemistry at King Saud University, Riyadh, Saudi Arabia. She received her PhD and Master’s degree in Analytical Chemistry from King Saud University, KSA in 1999. Her research is concerned with analysis of drugs and environmental samples by luminescence and electrochemical methods.

Maha F. El-Tohamy is currently a Researcher in Department of Chemistry, Faculty of Science, King Saud University. The author received her Ph.D. Pharmaceutical Sciences from Al-Azhar University, Cairo Egypt in 2010, where her analytical research was towards the green chemistry to minimize the formation of hazardous compounds.

Nawal M. Al Musayeib is a professor of pharmacognosy at King Saud University, Riyadh, Saudi Arabia. She received her PhD and Master’s degree in pharmacognosy at King Saud University, Riyadh, Saudi Arabia.

Hesham F. Oraby is an Assistant professor of plant biotechnology and molecular biology who received his Ph.D. from Michigan State University, USA in 2006. His research focuses on plant tolerance to biotic and abiotic stresses, and compounds with anticancer and antioxidant activities.