Viable but Nonculturable (VBNC) Bacteria

Culturing is one of the fundamental steps in microbiology. The plate count technique is a standard culturing method to enumerate viable bacteria. However, many bacterial cells could enter a distinct state called the viable but non-culturable (VBNC) state. The term “viable but nonculturable” or “not immediately culturable” describes cells that cannot normally be cultured. In most cases, the non-spore-forming bacteria are in a survival state (e.g., resting, dormancy, quiescence, or debilitation) with the metabolic pathways still being active, but the organisms are not growing.

• Challenges in Detecting Viable but Nonculturable Bacteria by Common Culture Methods
• Application of Ferrioxamine E in the Growth and Recovery of VBNC Bacteria
• Related Products Assisting in VNBC Detection

We offer ready-to-use agar plates, liquid media bottles, tubes, or ampoules, broths, and rinse fluids for your microbial testing application.

Challenges in Detecting Viable but Nonculturable Bacteria by Common Culture Methods

According to the latest definition, VBNC cells are regarded as viable and potentially replicative, but the methods required for resuscitation are beyond our current knowledge. With special media or with certain supplements it has been shown to recover them. VBNC bacteria have often undergone a treatment like heating, drying, setting under high osmotic pressure (high salt content), or contact with inhibiting chemicals. The treatment resulted in sensitive cells or sub-lethally damaged cells, which can be caused by the loss of some ribosomes, damaged enzymes, cell membranes, and other problems causing malfunctions in cells.

In recent years many species of Vibrio cholerae, E. coli, Campylobacter jejuni, Salmonella spp., Listeria monocytenenes, and Yersinia enterocolitica have been reported to be viable but non-culturable (VBNC) state. ^[1-10] It is important to note that bacteria that enter the VBNC state may become culturable again, and thus this state may be reversibly called “resuscitation” to describe the recovery of non-culturable cells. It was found that resuscitation can be mediated by a physical stimulus like temperature upshift and different kinds of chemical stimuli, including gas mixtures, amino acids, rich media, Supplements, etc. The addition of supplements to the re-enriched or enriched media has enabled to improvement of the recovery of many VBNC cells.

Application of Ferrioxamine E in the Growth and Recovery