Effect of feeding regimens on polyhydroxybutyrate production from food wastes by Cupriavidus necator

Abstract

List of abbreviations: PHA, polyhydroxyalkanoate; PHB, polyhydroxybutyrate; DO, dissolved oxygen; DCW, dry cell weight; COD, chemical oxygen demand; VFA, volatile fatty acid; D-COD, dissolved chemical oxygen demand; GC, gas chromatography; PHB-PHV, poly(3-hydroxybutyrate-co-3-hydroxyvalerate) 2 ABSTRACT We investigated the effects of different feeding regimens (1-pulse, stepwise, and continuous) of fermented food-waste liquid on polyhydroxybutyrate (PHB) production.The fermentation liquid was filtered with a membrane filter (pore size, 0.45 μm) to remove anaerobic microorganisms and solids and used as a carbon source for Cupriavidus necator. One-pulse feeding yielded the highest cell concentration of C.necator. However, the PHB concentration was higher in the stepwise-and continuous-feeding regimens. Therefore, the continuous-feeding regimen was used for continuous PHB production. PHB could be produced over 259 h (8 draw-fill cycles) with a maximal PHB content of 87%, but the PHB concentration and content decreased with an increase in the operation time.

Strategies for Large-scale Production of Polyhydroxyalkanoates

“…62 Another fed-batch strategy involving substrate feeding at a constant feed rate for P(3HB) production has been described. 31,64 A novel exponential feeding strategy based on alkali-addition monitoring was developed to maintain waste glycerol (substrate) at a constant level inside the bioreactor. 65 It resulted in a significantly high P(3HB) concentration of 65.6 g L -1 , yield of 62.7 % dcw, and productivity of 1.3 g L -1 h -1…”

Genome Sequence of an Efficient Indole-Degrading Bacterium, Cupriavidus sp. Strain IDO, with Potential Polyhydroxyalkanoate Production Applications

“…necator, are recognized as amazing pollutant-degrading bacteria (4, 5). Studies also show that they are efficient platforms for the production of polyhydroxyalkanoates (PHAs), which are promising substitutes for conventional petrochemical plastics due to their biodegradable and biocompatible merits, as they use waste material as a substrate (6, 7). Here, the genome sequence of Cupriavidus sp.…”

Utilization of kitchen waste for the production of green thermoplastic polyhydroxybutyrate (PHB) by Cupriavidus necator CCGUG 52238

“…While, pH-stat feeding has been employed by most of the researchers to feed short chain fatty acids (Kobayashi et al, 2000;Sugimoto et al, 1999;, for lactic acid and a mixture of lactic and acetic acids, feeding at different time intervals that is intermittent feeding strategy has been found to be more suitable (Tsuge et al, 2001;Linko et al, 1993;Tanaka et al, 1993). Very recently, Hafuka et al (2011) reported high PHB content (~87%) by continuous feeding of filtered fermented food wastes in C. necator. However, the biomass and PHB production rate was quite low as compared to others.…”

“…Significant research has been focused on using organic acids from fermented food wastes as raw materials for PHA production (Hafuka et , 2011;Du and Yu, 2002;Du et al, 2004). However, food waste in developing countries is usually denser than in developed areas, and its composition is an indicator of the socio-economic situation of the population (Holmes, 1984).…”