papers were reviewed here. In response to unsuitable environmental conditions ( starvation , salt stress , etc , ) , bacteria change their n ユ etabolic activity and cellular components to maintain viability for extended survival , and in some cases , enter a non − growing stage . VBNC bacteria clearly display vital physiological signs ( respira − tion and /or protein synthesis )and harbor vital celltllar components ( enzymes and / or nucleic acids )but do not multiply in ordirlary culture media

more »

... wi 亡 hout certain resuscita − tion processes . It is important to set up criteria for estimating the risk of VBNC human pa 亡 hogens such as Escherichia coli O157 and レ% ガ o cho ! erae in environment to prevent infeCtiOUS diSeaSeS frOm unknOWn SOUrCeS . MOSt heterOtrOphiC baCteria irl riVer water , seawater , activated sludge , and son are also considered VBNC and oligotrophism may be related to their behavior as VBNC bacter { a . Obhgate symbionts such as VA mycorrhizal fungi and obligate parasitic fungi such as Plasmodiophora brassicae are also nonculturable though they may not be considered VBNC rnicroorganisms . Their artificial cultivation is desired due to their agricultural significance . Developing new culture technologies for both VBNC bacteria and nonculturable fungi should be promQted as wel ! as Inolecular and fluorescent techniques . A multidisciplinary approach involving rnany microbiologists specialized in aquatic , sQi1 , medical arld physiological fields may enable to clarify these issues in future .