Growth kinetics, effect of carbon substrate in biosynthesis of mcl-PHA by Pseudomonas putida Bet001

Abstract

Growth associated biosynthesis of medium chain length poly-3-hydroxyalkanoates (mcl-PHA) in Pseudomonas putida Bet001 isolated from palm oil mill effluent was studied. Models with substrate inhibition terms described well the kinetics of its growth. Selected fatty acids (C8:0 to C18:1) and ammonium were used as carbon and nitrogen sources during growth and PHA biosynthesis, resulting in PHA accumulation of about 50 to 69% (w/w) and PHA yields ranging from 10.12 g L−1 to 15.45 g L−1, respectively. The monomer composition of the PHA ranges from C4 to C14, and was strongly influenced by the type of carbon substrate fed. Interestingly, an odd carbon chain length (C7) monomer was also detected when C18:1 was fed. Polymer showed melting temperature (Tm) of 42.0 (± 0.2) °C, glass transition temperature (Tg) of −1.0 (± 0.2) °C and endothermic melting enthalpy of fusion (ΔHf) of 110.3 (± 0.1) J g−1. The molecular weight (Mw) range of the polymer was relatively narrow between 55 to 77 kDa.

The Potential of Rhodotorula graminis TISTR 5124 for Synthesis of Polyhydroxyalkanoate (PHA) by Limitation of a Phosphorus and Nitrogen Sourc

“…A remarkable peak of C=O bond in the carbonyl ester group at the wavelength of 1734.91 cm -1 was observed and this is in agreement with the FTRI spectrum of standard PHB. Absorption at 3353.91 cm -1 is due to the presence of hydroxyl group (OH -) in a polymer chain (Gumel et al, 2014;Ma et al, 2009). The wavelength at 1559.85 cm -1 (NC=O) is assigned to a protein amid the traces remaining in the cells (Colthup et al, 1990).…”

“…The FTIR results reveal that the polymer produced by Rhodotorula graminis TISTR 5124 might possibly be the copolymer PHBV, when compared to the standard PHBV shown in Figure 5. Figure 4 FT-IR spectra of PHA extracted from Rhodotorula graminis TISTR 5124 cultured in P-limited condition Figure 5 FT-IR spectra of copolymer PHBV extracted from P. putida Bet001 (Gumel et al, 2014) The extracted polymer was also determined by 1 H NMR and the result is shown in Figure 6. When compared with the NMR spectra of copolymer PHBV in Figure 7, the peaks are very similar.…”

“…Overall, the FT-IR and NMR results can confirm that the polymer extracted from R.graminis TISTR 5124 is a PHA derivative or the copolymer PHBV. Figure 6 1 H NMR spectra of extracted PHA from R.graminis TISTR 5124 under P-limited condition Figure 7 1 H NMR spectra of copolymer PHBV extracted from P. putida Bet001 (Gumel et al, 2014) The amount of glucose consumed and the PHA production in each condition is shown in Table 3. It can be seen that P-limited condition resulted in the highest PHA yield of 65.1%, where the yeast consumed a minimum glucose amount of 3.2 g/L and cell growth reached the end of log phase (81 h) more rapidly than in other conditions (93 h).…”

Phytochemical Analysis and Antimicrobial Activity of Neocaryamacrophylla Leaves Extract

“…A sample of dried crude extract of Neocaryamacrophylla leaves (2 mg) was dissolved in 10 ml of chloroform, the mixture was filtered using a 25 ml borosilicate glass syringe equipped with disposable PTFE filter (Ø = 0.22µm). Filtered sample in the form were used for the GC-MS analysis according reported literature (Gumel et al 2014) with slight modification. Briefly, dissolved sample (1 µl) was automatically injected into the GC- …”

Unusual poly(3‐hydroxyalkanoate) (PHA) biosynthesis behavior of Pseudomonas putida Bet001 and Delftia tsuruhatensis Bet002 isolated from palm oil mill effluent

“…In this study, the accumulation of PHA in Pseudomonas putida Bet001 and D. tsuruhatensis Bet002 from various types of odd and even aliphatic acids, selected sugars, and glycerol as sole carbon and energy substrate was investigated. Both microorganisms were isolated from palm oil mill effluent (POME) and showed growth-associated PHA accumulation [3,4,24]. Variables namely final total biomass, yield of PHA, monomer fraction, and polymer properties of synthesized PHA were studied.…”