Polyhydroxyalkanoates (PHAs) are intracellular carbon and energy storage reserve material stored by gram-negative bacteria under nutrient limitation. PHAs are best alternative biodegradable plastics (bio-plastics) due to their resemblance to conventional synthetic plastic. The present study investigated the synergistic effect of nutritional supplements (amino acid and vitamin) on the PHA production by sp. NCIM 5085 utilizing a sugar refinery waste (cane molasses) under submerged fermentation process. Initially, the effect of individual factor on PHA yield was studied by supplementing amino acids (cysteine, isoleucine, and methionine), vitamin (thiamin), and cane molasses at varying concentration in the production medium. Further, the cultivation medium was optimized by varying the levels of cane molasses, methionine and thiamin using response surface methodology to enhance the PHA yield. The maximum PHA yield of 70.89% was obtained under the optimized condition, which was then scaled up on 7.5 L-bioreactor. Batch cultivation in 7.5 L-bioreactor under the optimized condition gave a maximum PHA yield and productivity of 79.26% and 0.312 gL h, respectively. The PHA produced was subsequently characterized as PHB by FTIR. PHB extracted was of relatively high molecular weight and crystallinity index. DSC analysis gave T, T, and X of 4.2, 179 °C and 66%, respectively. TGA analysis showed thermal stability with maximized degradation occurring at 302 °C, which is above the melting temperature (179 °C) of the purified polymer. The extracted polymer, therefore, possessed desirable material properties to be used in food packaging.
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http://dx.doi.org/10.1080/10826068.2019.1591982 | DOI Listing |
Bioresour Technol
December 2024
School of Water Conservancy and Transportation, Zhengzhou University, Zhengzhou 450001, China. Electronic address:
Angew Chem Int Ed Engl
December 2024
Chemistry and Chemical Engineering Guangdong Laboratory, 515031, Shantou, China.
Bioresour Technol
December 2024
Clean Energy Research Center, Korea Institute of Science and Technology (KIST), Seoul 02792, Republic of Korea; Division of Energy and Environment Technology, KIST School, University of Science and Technology, Seoul 02792, Republic of Korea. Electronic address:
Lignocellulosic biomass is a promising renewable feedstock for biodegradable plastics like polyhydroxyalkanoates (PHAs). Cupriavidus necator, a versatile microbial host that synthesizes poly(3-hydroxybutyrate) (PHB), the most abundant type of PHA, has been studied to expand its carbon source utilization. Since C.
View Article and Find Full Text PDFInt J Biol Macromol
December 2024
Department of Biology, Faculty of Science, Ferdowsi University of Mashhad, Mashhad, Iran; Industrial Biotechnology Research Group, Institute of biotechnology, Ferdowsi University of Mashhad, Mashhad, Iran; Nano Research Center, Ferdowsi University of Mashhad, Mashhad, Iran. Electronic address:
The controlled release of herbicides using new and safe materials can mitigate environmental pollution. Polyhydroxyalkanoate (PHA) is a type of biopolymer that can be produced by various bacteria. It has properties that make it suitable for encapsulation and controlled release applications.
View Article and Find Full Text PDFPolymers (Basel)
December 2024
School of Chemical Engineering, Pusan National University, Busan 46241, Republic of Korea.
In this study, a transient viscosity adjustment method using a coaxial nozzle was explored to fabricate nanofibers from non-spinnable -poly(hydroxyamide) (-PHA). Unlike conventional electrospinning methods that often require additives to induce fiber formation, this approach relies on a sheath-core configuration, introducing tetrahydrofuran (THF) to the sheath to temporarily adjust solution viscosity. The diffusion of THF into the core -PHA solution resulted in momentary solidification at the interface, promoting nanofiber formation without compromising polymer solubility.
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