Bioremediation of Heavy Metals and Toxic Chemicals …
77
8.4.5 Drop Collapse Test
The changes in the shape of crude oil sample was noted when added with extracted
crude biosurfactant in a cavity slide. This drop collapse may due to the force between
hydrophobic substrate and the liquid. The shape changes from spherical to flattened
indicates the presence of biosurfacatnt in the crude extract.
8.4.6 Thin Layer Chromatography (TLC)
Yellow colour spot was appeared when sprayed with anthrone reagent. It indicating
the interaction between the anthrone reagent with the rhamnose sugar present in the
crude sample.
8.5 Characterization of Biosurfactant by FTIR
The crude biosurfactant sample showing a strong and broad peak at 3279 cm
−1 indicating the O–H stretching vibrations of (free hydroxyl groups of rhamnose ring) in the
crude sample.Strong bonding of C=O stretch was noted at absorption of 1638 cm
−1
representing ester bonds and carboxylic acid function in the sample was reported
by (Rath et al. 2016). Another maximum adsorption was noted on peak value of
2115 cm
−1 showing C–C stretching of alkyne compounds. Medium intensity of peak
around 1540 cm
−1 determines C=O group in the sample was reported by (Mishra
and Trivedi 2019).The frequency around 1452 and 1397 cm
−1 indicating the presence of aliphatic bonds CH 3 , CH 2 , C–H stretching was observed. Similarly the peaks
around 1115 and 1016 cm
−1 representing C–O–C stretching in the rhamnose was
reported by (Rahman et al. 2002). These characteristic adsorption bands together
demonstrate the chemical nature of the sample was rhamnolipid as glycolipid type
of biosurfactant (Fig. 4).
9 Bioremediation of Heavy Metals by Biosurfactant
in Comparison with Biomass as Treatment Strategies
The untreated waste water sample was subjected to detect selectively four types
of heavy metals like Chromium, Lead, Zinc and Copper. Among these only the
chromium and lead was detected by Atomic absorption spectroscopy. Hence the
Muttukadu lake Chennai, water sample does not contain zinc and copper or they
may be present in trace amount which cannot be detected by Atomic absorption
spectroscopy. All the three following samples were tested for the presence of above
mentioned heavy metals.
77
8.4.5 Drop Collapse Test
The changes in the shape of crude oil sample was noted when added with extracted
crude biosurfactant in a cavity slide. This drop collapse may due to the force between
hydrophobic substrate and the liquid. The shape changes from spherical to flattened
indicates the presence of biosurfacatnt in the crude extract.
8.4.6 Thin Layer Chromatography (TLC)
Yellow colour spot was appeared when sprayed with anthrone reagent. It indicating
the interaction between the anthrone reagent with the rhamnose sugar present in the
crude sample.
8.5 Characterization of Biosurfactant by FTIR
The crude biosurfactant sample showing a strong and broad peak at 3279 cm
−1 indicating the O–H stretching vibrations of (free hydroxyl groups of rhamnose ring) in the
crude sample.Strong bonding of C=O stretch was noted at absorption of 1638 cm
−1
representing ester bonds and carboxylic acid function in the sample was reported
by (Rath et al. 2016). Another maximum adsorption was noted on peak value of
2115 cm
−1 showing C–C stretching of alkyne compounds. Medium intensity of peak
around 1540 cm
−1 determines C=O group in the sample was reported by (Mishra
and Trivedi 2019).The frequency around 1452 and 1397 cm
−1 indicating the presence of aliphatic bonds CH 3 , CH 2 , C–H stretching was observed. Similarly the peaks
around 1115 and 1016 cm
−1 representing C–O–C stretching in the rhamnose was
reported by (Rahman et al. 2002). These characteristic adsorption bands together
demonstrate the chemical nature of the sample was rhamnolipid as glycolipid type
of biosurfactant (Fig. 4).
9 Bioremediation of Heavy Metals by Biosurfactant
in Comparison with Biomass as Treatment Strategies
The untreated waste water sample was subjected to detect selectively four types
of heavy metals like Chromium, Lead, Zinc and Copper. Among these only the
chromium and lead was detected by Atomic absorption spectroscopy. Hence the
Muttukadu lake Chennai, water sample does not contain zinc and copper or they
may be present in trace amount which cannot be detected by Atomic absorption
spectroscopy. All the three following samples were tested for the presence of above
mentioned heavy metals.