Preliminary Study Of Berberine Antibacterial Characteristics And Antibacterial Mechanism

Ever since antibiotics became widely available about 50 years ago, they have been hailed as miracle drugs-magic bullets able to destroy disease-causing bacteria.But with each passing decade, bacteria that resist not only single, but multiple, antibiotics-making some diseases particularly hard to control-have become increasingly widespread. In fact, virtually all significant bacterial infections in the world are becoming resistant to the antibiotic treatment of choice.Disease-causing microbes that have become resistant to antibiotics are an increasing public health problem. Tuberculosis, gonorrhea, malaria, and childhood ear infections are just a few of the diseases that have become hard to treat with antibiotic drugs. Part of the problem is that bacteria and other microorganisms that cause infections are remarkably resilient and can develop ways to survive drugs meant to kill or weaken them. This antibiotic resistance, also known as antimicrobial resistance or drug resistance becomes a growing threat to human health. Many microbiological experts have focused their minds on this issue. Now there are some solutions to solve this problem, such as finding the new antibiotics, investigating the mechanism of antibiotics resistance. But these can't eradicate the growing threat of antibiotic resistance. Therefore, more and more people are drawing their attention to Chinese traditional medicine. There are many Chinese herbal medicine that can effectively inhibit the growth of microbes and kill them. The most important of all, bacteria doesn't show resistant to those Chinese medicines that were widely used to treat infections. In this article, we choose berberine, which is key component that take effects in a conventional Chinese herbal medicine (Coptis), as the target to elucidate its mechanism-against bacteria and compare it with-that of tradition antibiotics.The mode of action of berberine, which is a protoberberine alkaloid ,was studied in bacteria. Berberine inhibited strongly the growth of the Gram-positive bacteria, but weakly inhibited the growth of the Gram-negative bacteria at the same concentration.Berberine caused the leakage of Ca+ ions from the cell. To further confirm whether the bacterial surfaces were the target of berberine, scanning electron microscope(SEM) was used to get the image of bacteria after treatmeant with berberine. Berberine can intercalate DNA, and the large fluorescements observed when berberine binds to DNA^ In addition, We can use berberine to instead of EB to stain DNA after electrophoresis an see clear band under ultraviolet light. Berberine inhibited the incorporation of labeled precursors of DNA (thymidine), RNA (uridine) and protein(tyrosine) into macromolecular frations. These findings suggest that berberine intercalate DNA and RNA, then inhibit DNA synthesis, protein synthesis and RNA transcription may be involved in the berberine against bacteria. Our results indicate that berberine can inhibit the growth of bacteria through a multiple-targeted mechanism.