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Poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) [P(3HB-co-3HHx)] is a bacterial copolymer in the polyhydroxyalkanoates (PHAs) family, a next-generation bioplastic. Our research team recently engineered a newly P(3HB-co-3HHx)-producing bacterial strain, Cupriavidus necator PHB−4/pBBR_CnPro-phaCRp. This strain can produce P(3HB-co-2 mol% 3HHx) using crude palm kernel oil (CPKO) as a sole carbon substrate. However, the improvement of P(3HB-co-3HHx) copolymer production by this strain has not been studied so far. Thus, this study aims to enhance the production of P(3HB-co-3HHx) copolymers containing higher 3HHx monomer compositions using response surface methodology (RSM). Three significant factors for P(3HB-co-3HHx) copolymers production, i.e., CPKO concentration, sodium hexanoate concentration, and cultivation time, were studied in the flask scale. As a result, a maximum of 3.6 ± 0.4 g/L of P(3HB-co-3HHx) with 4 mol% 3HHx compositions was obtained using the RSM optimized condition. Likewise, the higher 3HHx monomer composition (5 mol%) was obtained when scaling up the fermentation in a 10L-stirrer bioreactor. Furthermore, the produced polymer's properties were similar to marketable P(3HB-co-3HHx), making this polymer suitable for a wide range of applications. [ABSTRACT FROM AUTHOR]

Polyhydroxyalkanoates (PHAs) are biodegradable polymers synthesized by certain bacteria and archaea with functions comparable to conventional plastics. Previously, our research group reported a newly PHA-producing bacterial strain, Rhodococcus pyridinivorans BSRT1-1, from the soil in Thailand. However, this strain's PHA synthase (phaCRp) gene has not yet been characterized. Thus, this study aims to synthesize PHA using a newly engineered bacterial strain, Cupriavidus necator PHB−4/pBBR_CnPro-phaCRp, which harbors the phaCRp from strain BSRT1-1, and characterize the properties of PHA for skin tissue engineering application. To the best of our knowledge, this is the first study on the characterization of the PhaC from R. pyridinivorans species. The results demonstrated that the expression of the phaCRp in C. necator PHB−4 had developed in PHA production up to 3.1 ± 0.3 g/L when using 10 g/L of crude palm kernel oil (CPKO) as a sole carbon source. Interestingly, the engineered strain produced a 3-hydroxybutyrate (3HB) with 2 mol% of 3-hydroxyhexanoate (3HHx) monomer without adding precursor substrates. In addition, the 70 L stirrer bioreactor improved P(3HB-co-2 mol% 3HHx) yield 1.4-fold over the flask scale without altering monomer composition. Furthermore, the characterization of copolymer properties showed that this copolymer is promising for skin tissue engineering applications. [ABSTRACT FROM AUTHOR]

This research investigated the impact of the concentration of pineapple juice on the characteristics of pineapple wine during fermentation with Saccharomyces cerevisiae var. burgundy. Three ratios of fresh pineapple juice to water were mixed to obtain three treatments, which were T1—2:1, T2—1:1, and T3—1:2. The °Brix and pH of all pineapple juice and water ratios were adjusted to 25 and 4, respectively. The results showed that changes in alcohol, pH, Total Soluble Solids (TSS), Total Titratable Acidity (TAA, as citric acid), and Volatile Acidity (VA, as acetic acid) during the 10-day fermentation among three treatments were significantly different. The highest alcohol content was obtained from the 2:1 with values of 10.71% (v/v). The mixed ratio at 1:1 and 1:2 obtained the alcohol value of 9.61 and 8.35% (v/v), respectively. After ten days of fermentation, TSS, pH values, TAA, and VA were in the range of 9.7–13 °Brix, 3.56–3.82, 0.384–0.448, and 0.0013–0.0016, respectively. However, the appearance, aroma, and taste of all ratios were not significantly different. Sweetness and overall liking, wine with pineapple juice/water ratio at 2:1 had the highest score (p ≤ 0.05). The total antioxidant activities determined by DPPH and total phenolic content were 0.91 mmol/L TE and 365.80 mg/L GAE, respectively, as confirmed by FTIR spectral analyses. [ABSTRACT FROM AUTHOR]

This study investigated the potential of using steam-exploded oil palm empty fruit bunches (EFB) as a renewable feedstock for producing fumaric acid (FA), a food additive widely used for flavor and preservation, through a separate hydrolysis and fermentation process using the fungal isolate K20. The efficiency of FA production by free and immobilized cells was compared. The maximum FA concentration (3.25 g/L), with 0.034 g/L/h productivity, was observed after incubation with the free cells for 96 h. Furthermore, the production was scaled up in a 3-L air-lift fermenter using oil palm EFB-derived glucose as the substrate. The FA concentration, yield, and productivity from 100 g/L initial oil palm EFB-derived glucose were 44 g/L, 0.39 g/g, and 0.41 g/L/h, respectively. The potential for scaling up the fermentation process indicates favorable results, which could have significant implications for industrial applications., Competing Interests: The authors declare that they have no competing interests., (© 2024 Boondaeng et al.)

Poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) [P(3HB-co-3HHx)] is a bacterial copolymer in the polyhydroxyalkanoates (PHAs) family, a next-generation bioplastic. Our research team recently engineered a newly P(3HB-co-3HHx)-producing bacterial strain, Cupriavidus necator PHB - 4/pBBR_CnPro-phaC Rp . This strain can produce P(3HB-co-2 mol% 3HHx) using crude palm kernel oil (CPKO) as a sole carbon substrate. However, the improvement of P(3HB-co-3HHx) copolymer production by this strain has not been studied so far. Thus, this study aims to enhance the production of P(3HB-co-3HHx) copolymers containing higher 3HHx monomer compositions using response surface methodology (RSM). Three significant factors for P(3HB-co-3HHx) copolymers production, i.e., CPKO concentration, sodium hexanoate concentration, and cultivation time, were studied in the flask scale. As a result, a maximum of 3.6 ± 0.4 g/L of P(3HB-co-3HHx) with 4 mol% 3HHx compositions was obtained using the RSM optimized condition. Likewise, the higher 3HHx monomer composition (5 mol%) was obtained when scaling up the fermentation in a 10L-stirrer bioreactor. Furthermore, the produced polymer's properties were similar to marketable P(3HB-co-3HHx), making this polymer suitable for a wide range of applications., (© 2023. The Author(s).)

Polyhydroxyalkanoates (PHAs) are biodegradable polymers synthesized by certain bacteria and archaea with functions comparable to conventional plastics. Previously, our research group reported a newly PHA-producing bacterial strain, Rhodococcus pyridinivorans BSRT1-1, from the soil in Thailand. However, this strain's PHA synthase ( phaC Rp ) gene has not yet been characterized. Thus, this study aims to synthesize PHA using a newly engineered bacterial strain, Cupriavidus necator PHB - 4/pBBR_CnPro- phaC Rp , which harbors the phaC Rp from strain BSRT1-1, and characterize the properties of PHA for skin tissue engineering application. To the best of our knowledge, this is the first study on the characterization of the PhaC from R. pyridinivorans species. The results demonstrated that the expression of the phaC Rp in C. necator PHB - 4 had developed in PHA production up to 3.1 ± 0.3 g/L when using 10 g/L of crude palm kernel oil (CPKO) as a sole carbon source. Interestingly, the engineered strain produced a 3-hydroxybutyrate (3HB) with 2 mol% of 3-hydroxyhexanoate (3HHx) monomer without adding precursor substrates. In addition, the 70 L stirrer bioreactor improved P(3HB- co -2 mol% 3HHx) yield 1.4-fold over the flask scale without altering monomer composition. Furthermore, the characterization of copolymer properties showed that this copolymer is promising for skin tissue engineering applications.

Bromelain is a mixture of proteolytic enzymes derived from pineapple ( Ananas comosus ) fruit and stem possessing several beneficial properties, particularly anti-inflammatory activity. However, the molecular mechanisms underlying the anti-inflammatory effects of bromelain are unclear. This study investigated the anti-inflammatory effects and inhibitory molecular mechanisms of crude and purified rhizome bromelains on lipopolysaccharide (LPS)-induced inflammation in RAW 264.7 macrophage cells. RAW264.7 cells were pre-treated with various concentrations of crude bromelain (CB) or purified bromelain (PB), and then treated with LPS. The production levels of pro-inflammatory cytokines and mediators, including nitric oxide (NO), interleukin (IL)-6, and tumor necrosis factor (TNF)-α were determined by Griess and ELISA assays. The expressions of inducible nitric oxide synthetase (iNOS), cyclooxygenase (COX)-2, nuclear factor kappa B (NF-κB), and mitogen-activated protein kinases (MAPKs)-signaling pathway-related proteins were examined by western blot analysis. The pre-treatment of bromelain dose-dependently reduced LPS-induced pro-inflammatory cytokines and mediators, which correlated with downregulation of iNOS and COX-2 expressions. The inhibitory potency of PB was stronger than that of CB. PB also suppressed phosphorylated NF-κB (p65), nuclear factor of kappa light polypeptide gene enhancer in B-cells inhibitor alpha, extracellular signal-regulated kinases, c-Jun amino-terminal kinases, and p38 proteins in LPS-treated cells. PB then exhibited potent anti-inflammatory effects on LPS-induced inflammatory responses in RAW264.7 cells by inhibiting the NF-κB and MAPKs-signaling pathways.

An actinomycete, strain DMKUA 245(T), isolated from soil, was investigated using a polyphasic approach. The isolate formed longitudinally paired spores on the tips of short sporophores that branched alternately from aerial hyphae. The morphological and chemotaxonomic properties clearly demonstrated that the new isolate belonged to the genus Microbispora. 16S rRNA gene sequence analysis supported the assignment of the novel strain to the genus Microbispora. The gene sequence similarity values between the novel strain and the closely related species Microbispora corallina, Microbispora rosea subsp. rosea, Microbispora rosea subsp. aerata and Microbispora amethystogenes were 98.4 %, 97.4 %, 97.0 % and 96.9 %, respectively. The DNA-DNA hybridization values and some physiological and biochemical properties indicated that strain DMKUA 245(T) could be distinguished from its phylogenetically closest relatives. Based on these genotypic and phenotypic data, strain DMKUA 245(T) represents a novel species in the genus Microbispora for which the name Microbispora siamensis sp. nov. is proposed. The type strain is strain DMKUA 245(T) (=BCC 14407(T)=NBRC 104113(T)). In addition, DNA-DNA relatedness values in reciprocal hybridization experiments showed that M. amethystogenes was a separate genomic species from M. rosea subsp. rosea. A combination of genotypic and phenotypic data supported the classification of M. amethystogenes as a separate species.