Thin‐Layer Chromatography for the Detection and Analysis of Bioactive Natural Products

Abstract

Thin‐layer chromatography (TLC) is a simple and cost‐effective technique, extensively used in natural products analysis. It is suitable for chemical and biological screening of herbal products and useful in monitoring bioguided isolation of active components. When coupled with appropriate detection methods, this versatile technique can provide qualitative or semi‐quantitative information on the chemical constituents of a complex mixture. For this purpose, the main advances in TLC include the development of highly efficient and reproducible methods, as in the case of high‐performance thin‐layer chromatography (HPTLC), and the development of several hyphenated techniques, including mass spectrometry (MS), Raman spectroscopy, and densitometry. Besides, several bioassays have been developed in combination with TLC separation for the on‐plate investigation of biological activity of natural products, a procedure known as bioautography. The major advantage of this technique is the ability to locate active substances from a complex mixture before compound purification. Overall, the recent advances in TLC analysis are a major contribution in avoiding time‐consuming and tedious isolation of already‐known or inactive phytochemicals. In this chapter, a comprehensive overview of TLC with chemical and biological detection is presented, with a focus on up‐to‐date bioautographic assays, their mechanisms, pitfalls, and recent advances in the field of natural products.

Screening for Antibacterial Activity of French Mushrooms against Pathogenic and Multidrug Resistant Bacteria

“…Furthermore, results can be affected by antagonist or synergistic effects. For these reasons, we decided to screen extracts by TLC-direct bioautography, which combines preliminary planar chromatographic separation of crude extracts and subsequent application of bacterial suspensions on eluted TLC plates [11]. This strategy enables us to evaluate the number of compounds involved in bioactivity, to assess if different bacterial strains are inhibited by the same or distinct compounds, and to get an idea about the polarity of active compounds according to their elution on the chromatographic plate.…”

Methods for screening and evaluation of antimicrobial activity: A review of protocols, advantages, and limitations

“…TLC-bioautography is a highly effective technique widely employed in natural product research for the screening and assessment of bioactive compounds including antimicrobial agents [ 77 , 78 ]. The fundamental principle of TLC-bioautography is based on the separation of components in a mixture using a TLC plate, followed by a direct bioassay performed on the plate for component detection ( Fig.…”

“…There are three main variants of TLC-bioautography, each differing in the method by which bacteria are introduced to the TLC plate: agar diffusion or contact bioautography, immersion or overlay bioautography, and direct TLC-bioautography ( Fig. 5 ) [ 78 ]. Each variant follows the initial step of conducting TLC to separate the components of the sample mixture.…”

Development of a thin‐layer chromatographic method for detection of lipstatin produced by Streptomyces toxytricini

“…Ideally, it remains constant under identical experimental conditions but affecting by various factors such as mobile phase, temperature, nature of the sample, TLC layer thickness, developing chamber, and so forth. The R x value of the sample was calculated by the following formula‐ R x = Distance traveled by sample/distance traveled by Standard [25, 26].…”