Production of xylooligosaccharides in SSF by Bacillus subtilis KCX006 producing β-xylosidase-free endo-xylanase and multiple xylan debranching enzymes

Xylanase and xylooligosaccharides (XOS) are employed in food and feed industries. Though xylanase production from lignocellulosic materials (LCMs) by solid-state fermentation (SSF) is well known, the XOS formed during growth is not recovered due to its conversion to xylose by β-xylosidase and subsequent bacterial metabolism. A new strain, Bacillus subtilis KCX006, was exceptionally found to synthesize β-xylosidase-free endo-xylanase and multiple xylan debranching enzymes constitutively in the presence of LCMs. Absence of β-xylosidase resulted in accumulation of XOS during growth of KCX006 on LCMs. Therefore, this strain was used for simultaneous production of xylanase and XOS from agro-residues in solid-state fermentation (SSF). Partial purification of XOS from culture supernatant using activated charcoal followed by high-performance liquid chromatography (HPLC) analysis showed xylobiose to xylotetraose formed as the major products. Among various LCM substrates, wheat bran and groundnut oil-cake supported highest xylanase and XOS production at 2158 IU/gdw and 24.92 mg/gdw, respectively. The levels of xylanase and XOS were improved by 1.5-fold (3102 IU/gdw) and 1.9-fold (48 mg/gdw), respectively, by optimization of culture conditions.     

Toward generation XL: Anthropometrics of longevity in late 20th-century United States

All-cause and cause-specific mortality among white U.S. men and women are analyzed using the NHANES I data (1971-1975) and epidemiologic follow-up to 1992, to examine the effect of physical stature on mortality, controlling for other confounding variables within a discrete-time framework. We find an association between mortality and both body mass index (BMI) and height, but the height effect is sensitive with respect to the age range under consideration. Although the resulting minimum-mortality BMI is higher than the widely accepted healthy range, the recent increase in weight implies that further gains in life expectancy are unlikely to derive from the anthropometry-mortality relationship.     

Neuroprotective Effect of 2-Aminoethoxydiphenyl Borate (2-APB) in Amyloid β-Induced Memory Dysfunction: A Mechanistic Study

Cellular and Molecular Neurobiology - β-Amyloid (Aβ) peptide is a characteristic feature of Alzheimer’s disease (AD) and accumulation of Aβ is associated with loss of synaptic...     

Raman spectroscopic studies of biological membrane model systems: Dietherlecithins

Raman spectra are obtained for the multilayer dispersion of rac-1,2,dioctadec-9′-cis-enyl-glycero-3-phosphorylcholine (dietherlecithin) in excess water. The CH stretching region was studied as a function of temperature and indicates that the multilayer dispersions undergo a liquid crystal to the gel phase transition at ?21 ± 4°C.     

Raman studies of the C-H and C-D stretching regions in stearic acid and some specifically deuterated derivatives

Raman spectra of polycrystalline stearic acid-d₀, stearic acid-d₃₅, 16:16-d₂-18:18:18-d₃-stearic acid, 18:18:18-d₃-stearic acid, 17:17-d₂-stearic acid, 17-d₁-stearic acid, 16:16-d₂-stearic acid, 12:12-d₂-stearic acid and 12-d₁-stearic acid have been obtained for the region containing the C-D and C-H stretching vibrations. Assignments of the methyl, methyl-d₃, methylene, methylene-d₂ and methylene-d₁ stretching vibrations are discussed.     

Influence of Oral Administration of Bacillus subtilis on Growth Performance and Physiological Responses in Litopenaeus vannamei Cultured in Low Saline Waters

Probiotics and Antimicrobial Proteins - The present study examined the effect of Bacillus subtilis on growth performance, digestive enzyme activity, and immune response of juvenile white-leg shrimp...     

Precision fermentation with mass spectrometry-based spent media analysis

Optimization and monitoring of bioprocesses requires the measurement of several process parameters and quality attributes. Mass spectrometry (MS)-based techniques such as those coupled to gas chromatography (GCMS) and liquid Chromatography (LCMS) enable the simultaneous measurement of hundreds of metabolites with high sensitivity. When applied to spent media, such metabolome analysis can help determine the sequence of substrate uptake and metabolite secretion, consequently facilitating better design of initial media and feeding strategy. Furthermore, the analysis of metabolite diversity and abundance from spent media will aid the determination of metabolic phases of the culture and the identification of metabolites as surrogate markers for product titer and quality. This review covers the recent advances in metabolomics analysis applied to the development and monitoring of bioprocesses. In this regard, we recommend a stepwise workflow and guidelines that a bioprocesses engineer can adopt to develop and optimize a fermentation process using spent media analysis. Finally, we show examples of how the use of MS can revolutionize the design and monitoring of bioprocesses.