Abstract:

The semi-synthesis and antibacterial study of penicillin V potassium is primarily an interdisciplinary experiment. Currently, only a few foreign universities such as the Massachusetts Institute of Technology (MIT) allow undergraduate students to conduct this experiment. To incorporate a research-like environment into teaching experiments and enable students to develop scientific thinking, the following improvements were made to the experiment: 1) A circulating condensing device was designed and built, and low-temperature control was introduced to improve the stability of the products and effectively reduce the formation of by-products. 2) Absolute ethyl alcohol was added to remove the by-products based on solubility difference. 3) The minimum inhibitory concentration of penicillin was determined using the microbroth dilution method, and antibiotic sensitivity was determined using the Oxford penicillin cup method. 4) The effects of penicillin on the integrity of bacterial cell walls were characterized via wheat germ agglutinin fluorescent labeling combined with confocal fluorescence microscopy. This comprehensive experiment, which combines several important multidisciplinary concepts, can develop students' skills in integrated analysis and increase their interest in scientific research.

Key words: Penicillin synthesis, Circulating condensation device, The minimum inhibitory concentration, Fluorescent label, Fluorescence confocal microscope