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R. Baishya and S. Banerjee
that grapefruit juice has an anti-biofilm effect against E. coli and S. typhimurium by
interfering with quorum sensing (Truchado et al. 2015).
3.3 Quantification of EPS Components
The amount of the protein and carbohydrate of the control and treated EPS samples
was measured at the optical densities of 660 nm and 620 nm, respectively. The
inhibition percentage of the given samples was calculated and was observed that there
was a gradual decrease in the amount of protein (Fig. 3) and carbohydrate (Fig. 4)
in treated EPS compared to control with increase in plant extracts concentration.
Carbohydrate and proteins were the main components o f EPS matrix. In the
present study, the percentage of carbohydrate and protein present in the EPS was
relatively less after treatment with plant extracts. Gandhi et al. 2017 reported similar
results when Sesbania grandiflora extract was treated against Staphylococcus aureus.
128*MIC
256*MIC
512*MIC
Concentration
128*MIC
256*MIC 512*MIC
Concentration
128*MIC
256*MIC 512*MIC
Concentration
a
b
c
Fig. 3 Estimation of percentage reduction of protein with respect to control a neem, b haldi,
c vancomycin (n = 3)
128*MIC
256*MIC 512*MIC
Concentration
128*MIC
256*MIC 512*MIC
Concentration
128*MIC
256*MIC 512*MIC
Concentration
a
b
c
Fig. 4 Estimation of percentage reduction of carbohydrate content with respect to control a neem,
b haldi, c vancomycin