Detection and Expression of Biosynthetic Genes in Actinobacteria ...

BERVANAKIS, G.Chapter 3: RESULTSThe UV-Vis spectra of the actinobacterial extracts showed a number of chemicalspecies absorbing at a various wavelengths (Table 56). The λ max is an importantcharacteristic in identifying the class of compound being investigated as certaincompounds are known to absorb at certain wavelengths. This information wasretained to form a chemical profile of the unknown compound and perform a databasesearch in section 3.2.10.Table 56. Maximum absorption wavelength λ max detected fromsemi-purified extracts using UV-Vis Spectroscopy.IsolateWavelength λ max (nm)NumberA0350 257, 310, 329, 338, 356, 425, 475A1113 257, 310, 329, 338, 356, 425, 475A2381 257, 425A2707 257A3675 257, 310, 329, 338, 356A2360 257A0347 2573.2.7 Reverse Phase High Performance LiquidChromatography of Semi-Purified AntimicrobialOrganic ExtractsIn order to further characterize the chemical species in the organic extracts from theactinobacterial cultures reverse-phase high performance liquid chromatography (RP-HPLC) was employed with Photo Diode Array (PDA) detection. The chromatogramshown in figure 36 of A1113 and A0350 indicates that there are two distinctivecomponents present at retention times 11.68 and 11.86 mins (Figure 36A) containingidentical chromophores (Figure 36B) with maximum absorbance at approximately240 nm._____________________________________________________________________108