plackett-burman design was used for selection of important media components such as carbon and nitrogen sources and minerals which affect poly(hydroxybutyrate) production and cell growth of methylobacterium extorquens dsmz 1340. among the studied variables, nitrogen and phosphorus sources, mgso4 and most of the trace elements were found to be significant variables for phb production from methan...

The equilibrium adsorption of bovine serum albumin (BSA) on poly-3-hydroxybutyrate (PHB) and poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) surfaces was studied at different solution concentrations. data were fitted to the Langmuir Freundlich models. protein behaviour further investigated by analysing conformation surface adsorbed BSA using Fourier transform infrared (FTIR) spectroscopy wi...

Ketone bodies are neuroprotective in neurological disorders such as epilepsy. We randomly studied nine healthy human subjects twice-with and without continuous infusion of 3-hydroxybutyrate-to define potential underlying mechanisms, assessed regionally (parietal, occipital, temporal, cortical grey, and frontal) by PET scan. During 3-hydroxybutyrate infusions concentrations increased to 5.5±0.4 ...

A gas chromatography-mass spectrometry (GC-MS) method for determination of ketone bodies (β-hydroxybutyrate, acetone, and acetoacetate) in blood is presented. The method is based on enzymatic oxidation of D-β-hydroxybutyrate to acetoacetate, followed by decarboxylation to acetone, which was quantified by the use of headspace GC-MS using acetone-(13)C(3) as an internal standard. The developed me...

The metabolism of millimolar concentrations of R- or S-1,3-butanediol has been studied in perfused livers from fed and starved rats. Protocols were designed to measure in the same experiment (i) uptake of the diol, (ii) the contribution of the diol to ketogenesis, (iii) the contribution of the diol to total fatty acid plus sterol synthesis, and (iv) conversion of S-1,3-butanediol into S-3-hydro...

Cardioprotection of dexrazoxane (DZR) against doxorubicin (DOX)-induced cardiotoxicity is contentious and the indicator is controversial. A pairwise comparative metabolomics approach was used to delineate the potential metabolic processes in the present study. Ninety-six BALB/c mice were randomly divided into two supergroups: tumor and control groups. Each supergroup was divided into control, D...

The relationship between butirosin biosynthesis and certain biochemical characteristics related to sporulation in a strain of Bacillus circulans NRRL B-3313 was examined. The cellular content of dipicolinic acid increased while the amount of poly-beta-hydroxybutyrate decreased with changes in antibiotic productivity. Oligosporogenous mutants failed to synthesize the antibiotic and to degrade po...

poly-β-hydroxybutyrate (phb), produced by several species of bacteria, has attracted great attention as a biodegradable and biocompatible compound with almost similar properties of polypropylene. unfortunately, its use is currently limited due to high production costs. one of the most common methods for overcoming this constraint is the use of inexpensive substrates, like methanol. another stra...

1. The injection of L-alanine (50-100 mg/kg) into 35-day-old rats that had been starveed for 48 h increased blood L-alanine concentration to values observed in fed animals and lowered the blood concentration of 3-hydroxybutyrate within 2 min. 2. This hypoketon aemic action of L-alanine was specific for 3-hydroxybutyrate, since the acetoacetate concentrations did not change significantly. 3. The...

A biosensor for 3-hydroxybutyrate (3-HB) involving immobilization of the enzyme 3-hydroxybutyrate dehydrogenase onto a screen-printed carbon electrode modified with reduced graphene oxide (GO) and thionine (THI) is reported here. After addition of 3-hydroxybutyrate or the sample in the presence of NAD⁺ cofactor, the generated NADH could be detected amperometrically at 0.0 V vs. Ag pseudo refere...