甘氨酸-万古霉素-多粘菌素-环己酰亚胺琼脂(GVPC)是检测军团菌属的推荐培养基。在水样中。然而,从军团菌的回收率来看,它的质量可以提高。和选择性性质。在GVPC制造中引入了修改:高压灭菌条件(115°C,15分钟)和组分搅拌过程中的气氛(除去氧气和N2注入)。使用较软的高压灭菌条件(115°C,15min)提高了螺旋法的anisa军团菌和膜过滤后的嗜肺军团菌的生长。去除O2并在115°C下高压灭菌15分钟制造的培养基允许嗜肺乳杆菌的更快生长(在第2天可见菌落)和anisa乳杆菌生长的显著增加(菌落出现在第3天,并且在第5天具有统计学意义的CFU数目)。经过3到5天的孵化,改进后的介质显示出更高的选择性,特别是粪肠球菌ATCC29212和铜绿假单胞菌ATCC9027。通过在配料搅拌过程中添加N2实现了进一步的改进,导致在第2天和第3天的嗜肺乳杆菌和在第3天的anisa乳杆菌的统计学上显着的更快生长。选择性也增强了,导致粪肠球菌菌株和大肠杆菌的完全抑制和铜绿假单胞菌的完全-部分抑制。使用真空泵系统在GVPC制造过程中的氧气去除可促进肺炎支原体和anisa的生长,并显著抑制大肠杆菌的生长,铜绿假单胞菌,和粪肠杆菌。目前的重要性,GVPC是军团菌属检测的推荐培养基。在水样中。然而,军团菌的恢复。和选择性性能可以得到改善。无氧生产的GVPC培养基改善了嗜肺军团菌和anisa军团菌的生长。在GVPC制造期间的氧去除也改善了选择性性质。通过在配料搅拌过程中添加N2实现了进一步的改进,导致第2天和第3天嗜肺乳杆菌和第3天anisa的更快生长,并增强了选择性。在常规实践中引入改良的GVPC培养基可以更好地检测军团菌。在水样中。
Glycine-vancomycin-polymyxin-cycloheximide agar (
GVPC) is a recommended medium for the detection of Legionella spp. in water samples. However, its quality could be improved in terms of recovery of Legionella spp. and selectivity properties. Modifications were introduced in
GVPC manufacture: autoclaving conditions (115°C, 15 min) and atmosphere during component-stirring (removal of oxygen and N2 injection). The use of softer autoclaving conditions (115°C, 15 min) improved the growth of Legionella anisa by the spiral method and Legionella pneumophila after membrane filtration. The medium manufactured with O2 removal and autoclaving for 15 min at 115°C allowed a faster growth of L. pneumophila (colonies visible at day 2) and a notable increase of L. anisa growth (colonies appearing at day 3, and statistically significant numbers of CFU at day 5). After 3 to 5 days of incubation, the improved media showed higher selectivity properties, particularly for Enterococcus faecalis ATCC 29212 and Pseudomonas aeruginosa ATCC 9027. A further improvement was achieved by the addition of N2 during ingredient stirring, leading to a statistically significant faster growth of L. pneumophila at days 2 and 3 and L. anisa at day 3. Selectivity properties were also enhanced, resulting in the complete inhibition of both E. faecalis strains and Escherichia coli and complete-partial inhibition of P. aeruginosa. Oxygen removal during
GVPC manufacture using a vacuum pump system promotes the growth of L. pneumophila and L. anisa, and markedly inhibits the growth of E. coli, P. aeruginosa, and E. faecalis. IMPORTANCE Currently, GVPC is a recommended medium for the detection of Legionella spp. in water samples. However, recovery of Legionella spp. and selectivity properties can be improved.
GVPC medium manufactured without oxygen improved the growth of Legionella pneumophila and Legionella anisa. Oxygen removal during
GVPC manufacture also improved selectivity properties. A further improvement was achieved by the addition of N2 during ingredient stirring, leading to a faster growth of L. pneumophila at days 2 and 3 and L. anisa at day 3 and enhancement of selectivity properties. The introduction of the modified GVPC medium in routine practice can allow a better detection of Legionella spp. in water samples.