Figure 6
Influence of the direct contact of 1-octanol (OcAq) and aqueous tea extract (TeaAq) on IAA production in Pseudomonas sp. NEEL19, cultured in the presence/absence of 0.1% (w/v) Trp. (a) and (b) respectively show IAA production in the absence and presence of 0.1% (w/v) Trp when supplied with 5% (v/v) 1-octanol (OcAq) and 5% (v/v) aqueous tea extract (TeaAq). NB and NBW, full-strength nutrient broth (Himedia) without and with 0.1% (w/v) Trp, respectively. + , cells present; –, cells absent. Cell-free NB and NBW were used as controls in (a) and (b), respectively. (c) and (d) show IAA production at low concentrations (< 1%) of OcAq and TeaAq present in DSMZ 125* with 0.1% (w/v) Trp supplement, respectively. BMW without OcAq and TeaAq supplement were used as controls in (c) and (d), respectively. Microplate sections (insert, a–d) obtained in this study represent chromogenic reactions of respective IAA assay. Error bar, mean (n = 4) ± s.d. **P < 0.05, ***P < 0.01, ****P < 0.0001; ns, non-significant.
