What is the infection risk of oesophageal dilatations?

Oesophageal dilatation is the most widely used treatment option for the management of oesophageal strictures. Complications include bleeding, a slight increase in body temperature, thoracic or abdominal pain, oesophageal perforation, brain abscess and bacteraemia. We performed a prospective study to evaluate the frequency of post-dilatation bacteraemia in nine patients subjected to a total of 50 dilatations. Bacteraemia was detected in 36 cases (72%), In all but three cases, however, it was transient and not associated with fever or other clinical complications. The organisms most commonly responsible (64%) were alpha-haemolytic streptococci (Streptococcus viridans), probably originating as contaminants from the oropharynx and oesophagus and introduced into the bloodstream during dilatation. Despite the relatively low incidence of bacteraemia-related postdilatation complications, the potential severity of such complications argues for the use of antibiotic prophylaxis as a routine measure prior to oesophageal dilatation. CONCLUSION: Oesophageal dilatation is associated with a high incidence of bacteraemia. The organisms most commonly responsible were alpha-haemolytic streptococci. We recommend the use of antibiotic prophylaxis as a routine measure prior to oesophageal dilatation.     

Determination of the relationship between oxalate degradation and exopolysaccharide production by different Lactobacillus probiotic strains

The aim of this study was to evaluate the protective effects of exopolysaccharide (EPS) production on resistance to gastrointestinal digestive conditions and oxalate by probiotic strains of the species Lactobacillus rhamnosus, Lactobacillus fermentum and Lactobacillus brevis. The oxalate‐degrading ability of the strains was determined using an enzymatic assay. The correlation between oxalate degradation rate and EPS production was not significant (P > 0.05); however, the high‐EPS‐producing L. fermentumIP5 and L. brevisYG7 strains showed high oxalate‐degrading activity, whereas the low‐EPS‐producing strain L. fermentumBP5 demonstrated low oxalate‐degrading activity. The present findings suggest that dietary supplementation with the probiotic strain L. fermentumIP5 could be a promising strategy for the prevention of oxalate stone disease.     

Slaughterhouse Blood: An Emerging Source of Bioactive Compounds

Slaughterhouse blood is an inevitable part of the meat production food chain and represents a rich source of protein. The physicochemical characteristics and utilization of animal blood in various food and industrial applications has been well explored. However, in recent years much attention has been paid to the generation of peptides with biological activities from food by‐products including blood. This review examines the angiotensin‐converting enzyme inhibitory, antioxidant, antimicrobial, and other bioactive peptides derived from various slaughterhouse animal blood sources. Furthermore, the effect of enzyme choice, degree of hydrolysis, and peptide sequence or size on the potency of these bioactivity is discussed.     

The effects of different technologies on<Emphasis Type="Italic"> Alicyclobacillus acidoterrestris</Emphasis> during apple juice production

In this study, the effects of various processing steps applied during apple juice processing on Alicyclobacillus acidoterrestris were investigated. Raw apple juice was inoculated with A. acidoterrestris spores at two inoculum levels of 1×10³ cfu/ml and 1×10⁶ cfu/ml. Following enzymatic treatment, the raw juice was processed into clear juice using either conventional clarification or ultrafiltration. The number of A. acidoterrestris spores in the final product was determined to be dependent on both initial contamination level and processing conditions. Increasing temperature to 50 °C during depectinization resulted in a higher spore counts at both inoculum levels. Even if the ultrafiltration process was found to be much more convenient for the retention of A. acidoterrestris when compared to conventional clarification, the spores could penetrate the ultrafiltration membranes having both 20 and 50 kDa. Increasing membrane pore size and initial spore counts in the feed solution also increased the number of spores penetrating the membrane during ultrafiltration.     

Reversible degradation kinetics of vitamin C in peas during frozen storage

In this study, kinetics of ascorbic acid (AA, 2-oxo-l-threo-hexono-1,4, lactone-2,3 enediol) and dehydroascorbic acid (DHAA, threo-2,3-hexodiulosonic acid-γ-lactone) were studied in blanched and unblanched peas during frozen storage using a first order reversible consecutive reaction model. The time-dependent changes for both AA and DHAA were strongly correlated with the kinetic model described here. Blanching resulted in 19% of reduction in k ₁ value (AA degradation rate constant) as compared with unblanched peas (0.227/month±5.43×10⁻³/month). The regeneration rate constant of AA (k ₂) increased approximately 26 folds for blanched peas when compared to unblanched peas (0.0114/month±1.04×10⁻³/month). Rate constant (k ₃) for the conversion of DHAA into 2,3-diketogulonic acid (DKGA) in blanched peas decreased approximately 31 folds by blanching treatment. This kind of kinetic analysis may be used for better understanding the effects of processing and storage conditions on vitamin C.     

Determination of guaiacol produced by Alicyclobacillus acidoterrestris in apple juice by using HPLC and spectrophotometric methods, and mathematical modeling of guaiacol production

In this study, easy detection of Alicyclobacillus acidoterrestris was performed by determination of guaiacol in apple juice. Guaiacol produced by A. acidoterrestris was determined by using HPLC, UV-Vis spectrophotometer, and Minolta spectrophotometer. Statistical analysis showed that the methods used for measuring the guaiacol concentrations were not significantly different (p > 0.05). Guaiacol formation in apple juice spiked with different levels of A. acidoterrestris spores was also analyzed using Gompertz, Logistic, and Richards models. In all cases, a good agreement between experimental data and fitted values was obtained. Using the modified Gompertz model, the derived biological parameters were calculated. Guaiacol formation rates (μ) and final guaiacol concentrations (A) were very similar in all cases, regardless of the initial A. acidoterrestris spore counts. However, lag phase durations (λ) were found to be dependent on the initial bacterial counts, and increased from 28.4 to 37.6 h, when initial inoculation level decreased from ∼10³ to ∼10¹ cfu/mL.     

Electrochemical sensing of NADH on NiO nanoparticles-modified carbon paste electrode and fabrication of ethanol dehydrogenase-based biosensor

In this work, an electrochemical β-nicotinamide adenine dinucleotide (NADH) sensor based on a carbon paste electrode modified with nickel oxide nanoparticles (NiONPs) was developed. The key highlights of this work are ease of preparation of the NiONPs-modified carbon paste electrode (NiONPs/MCPE), and its high sensitivity to NADH. The electrochemical characterization of NiONPs/MCPEs was performed via cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). The electrochemical oxidation response of NADH was investigated by differential pulse voltammetry and chronoamperometry. The results indicated that the electrocatalytic effects of NiONPs on the response current of NADH significantly facilitated the electron transfer and improved the performance of the biosensor. Compared to bare carbon paste electrode (BCPE), the oxidation potential was shifted toward more negative potentials and the oxidation current was increased remarkably. Under optimum conditions, NADH could be detected in the range from 1.0 × 10^?4 to 1.0 mmol L^?1 with lower detection limit (0.05 μmol L^?1). The proposed NADH sensor demonstrated fast and reproducible response. Furthermore, an ethanol biosensor was prepared using NiONPs and NAD⁺-dependent alcohol dehydrogenase enzyme giving linear responses over the concentration range of 1.6 and 38 mmol L^?1 of ethanol.     

Patterns of decomposition and nutrient release by fresh Gliricidia (Gliricidia sepium) leaves in an ultisol

Legume leaves used as green manure are a potential alternative to the use of commercial N fertilizers for non-legume crop production. Thus it is important to understand the rate of legume leaf decomposition and its release of nutrients. This paper reports the results of a litter bag experiment using fresh Gliricidia sepium leaves under field conditions. The leaves were confined in litterbags (5.3 mm mesh) and buried 10 cm in the soil. Dry matter, C, N, P, K, Ca, and Mg remaining after decomposition was determined at 0, 5, 10, 20, 30, 40, 50, 60 and 70 days. A rapid initial phase followed by a much slower one was identified in the decay and nutrient release patterns. The duration of the former ranged from 21 to nearly 30 days for dry matter and nutrients. Potassium and Ca were the most rapidly released nutrients, with the early phase lasting 28 and 6 days respectively. Nitrogen and P showed similar patterns of release and initial phase duration (21 and 22 days). Their rate constants were also 10 and 8 times that of their respective slow phases. C:N and C:P ratios increased initially and then decreased in the subsequent phase of decomposition. Magnesium also gave an identical pattern and rate of release as N in the early phase. No influence of rainfall was observed on the parameters studied.     

Characterization of crude lipoxygenase extract from green pea using a modified spectrophotometric method

In the spectrophotometric assay of lipoxygenase (LOX), the buffered linoleic acid solution used as the reaction medium is not optically clear enough at neutral or lower pH values, due to its limited solubility, to provide a precise, accurate and reproducible estimation of activity as the increase in absorbance at 234 nm. Therefore, an optically clear solution was obtained by formation of the Na-salt of unreacted linoleic acid before absorbance measurement. The modified method was then used to characterize crude LOX from green peas in terms of pH and temperature optima, thermal stability, and kinetic parameters. The optimum pH and temperature for the activity of LOX from green peas were determined to be 6.0 and 30 °C, respectively. LOX was found to be very stable at 60 °C, but much less stable at 65 °C or higher temperatures. The Michaelis constant (K_m) and maximum rate (V_max) for linoleic acid were calculated to be 1666 units per mg protein per min and 2.33 mM, respectively.