As the present trend throughout the world is shifting towards the use of ecofriendly and biodegradable commodities, there is an increasing need for natural pigments. However, the applications of natural pigments in human life are diverse and still in growing stages. Thus, attempt was made to isolate and identify pigment producing bacteria from squid and lala. In this study, four yellow-orange pigment producing bacteria, namely SO1, SO2, LO1 and LY1 were morphologically analyzed via Gram staining technique before being further identified and characterized using a series of biochemical test, including Indole, Methyl Red, Voges-Proskauer (VP), Catalase, Citrate, Nitrate Reductase, Urease, and Triple Sugar Iron (TSI). All four pigmented bacterial isolates were identified as Gram-negative with either bacillus or coccus shape. Three of the bacterial isolates produced orange pigment (SO1, SO2 and LO1) and showed positive result in Methyl Red (MR), Voges-Proskauer (VP), Catalase and Nitrate Reductase tests, while exhibited negative result in Indole, Citrate, Urease and Triple Sugar Iron (TSI) biochemical analysis. The other one yellow pigment bacterial isolate (LY1) was positive in three biochemical tests (MR, Catalase and Nitrate Reductase) and negative in five biochemical analysis (Indole, VP, Citrate, Urease and TSI). Each isolated pigment producing bacteria was also examined for their effect on growth parameters, including type of media (Nutrients agar, Luria-Bertani agar, Peptone-Glycerol agar), incubation temperature (30 degrees C and 37 degrees C) and incubation time (5 days and 7 days). Among three different types of agar media used, Luria-Bertani agar exhibited high bacterial growth and intense pigment production. Whilst, the optimum temperature and periods for pigment production was observed at 30 degrees C and 5 days respectively.

Pharmacodynamic research plays an important role in the development of new antibacterial agents. Characterization of this pharmacodynamic can be used to design the best dose and dosing strategy for clinical trials. The pharmacodynamic properties can be determined by studying the bactericidal activity and the postantibiotic effects (PAE). Measurements of both bactericidal activity and the lag time could be useful in screening the efficacy of antimicrobial agents. In this study, the pharmacodynamic properties of essential oils from Cymbopogon flexuosus (lemongrass) and Cymbopogon nardus (citronella) as well as the combinations of both essential oils were evaluated against Staphylococcus aureus and Escherichia coli. At high concentrations (1.0 x minimum bactericidal concentration (MBC) and 0.5 x MBC), citronella and lemongrass essential oils alone or in combinations indicate high bactericidal activities toward S. aureus and E. coli, as shown by the decrease of optical absorbance values serially up to 24 h. However, these two essential oils or its combinations at lower concentrations (0.25 x MBC and 0.125 x MBC) showed the bacterial regrowth after 3 and 1 h of exposure time against S. aureus and E. Coli, respectively. Generally, citronella and lemongrass essential oils as well as its combinations indicate a significant lag of regrowth or PAE values which were more than 0.5 h towards both E. coli and S. aureus. This finding suggests that essential oils from Cymbopogon species showed a potential antimicrobial activity that can further be used for clinical treatment; thus, there is need for a study on the possible impact of PAE in the clinical situation.