Natural products have formed the basis of traditional medicine systems
throughout human history. Today, drug discovery studies from natural origins continue
rapidly and efficiently with modern methods. Among the many activities, cytotoxic
activity is related to the behaviour of test material on cell viability and cellular growth.
Cytotoxicity methods, used as a screening test or initial test for guiding other activities,
provide useful information for biocompatibility studies for medical devices or
materials, drug discovery and development processes, toxicity evaluation of cosmetics,
research of disease mechanisms and treatments, and determination of chemopreventive
agents. In vitro cytotoxicity analyses have emerged as an alternative to in vivo studies
and have become preferable due to their ease of application, standardization, rapid, low
cost, and compatibility with data from in vivo studies. With cell-based cytotoxicity
studies, basic information about the cytostatic and cytotoxic effects of the tested
substance is obtained. In studies dealing with natural products, the most appropriate
cytotoxic method should be selected according to the properties and chemical
structures of natural compounds, the ultimate goal of the study, cell types, etc.
Although there are many cytotoxicity methods, this chapter is an introductory overview
of the most commonly used assay methods to estimate the cytotoxic activity in natural
products.
Keywords: Cytotoxicity, Natural products, Phytochemicals, Colorimetric Methods, Metabolic cell proliferation assays, Dye exclusion assays.
