Control of swelling and release rate of electrospray fabricated calcium alginate microparticles by freeze-thaw cycles

To improve structure of the electrospray fabricated calcium alginate microhydrogels in order to control the swelling and release properties, Poly (vinyl alcohol) (PVA) and poly(vinyl pyrrolidone) PVP were used and structure of the microhydrogels were reinforced by two freezing and thawing cycles. The particles did not show any swelling in HCl (pH=1.2). Swelling in the phosphate buffer (pH=7.4) showed amending effect of PVA and PVP and freeze-thaw cycles on the particles. In phosphate buffer media the freeze dried calcium alginate particles (ALG), the particles which improved by PVA and PVP (FD) and particles reinforced by freeze-thaw cycles (FT) showed swelling of 244.65, 152.15 and 126.34% respectively after 8 hours. On the other hand release rate of caffeine as a hydrophilic compound delayed in the FD and FT particles. According to the FTIR spectra, caffeine was entrapped physically in the particles. Results showed that calcium alginate particles reinforced with PVA and PVP especially those were undergone on freeze-thaw cycles could be applied for more efficient encapsulating of bioactive compounds without any chemical cross-linkers

Method of Production and Assessment of anEncapsulated Choline Chloride and Its Effects on GrowthPerformanceand Serum LipidIndices in Broilers

Since, choline chloride caking causes serious operating difficulties and customer complaints, two experiments were conducted to optimize in vitro production of a novel encapsulated choline chloride (ECC) with minimum hygroscopic property and optimize delivery in gastrointestinal tract (GIT). The in vivo verification test of ECC was used to compare it with the commercial choline chloride (CC) in Ross 308 broiler chickens. Twelve factors with 3 levels including 27 formulations on ECC properties were evaluated using the Taguchi method (signal/noise ratio analysis).  The produced ECC particles showed a decrease in hygroscopic property and release rate under simulated GIT. The in vitro study showed that the encapsulation efficiency of 27 formulations were ≥ 80% and choline content in ECC particles ranged from 507 to 718 g/kg (wt/wt). The oil, wax, whey protein concentrate (WPC), and calcium stearate contents had the most influence on hygroscopic property (P < 0.05). The ECC particle gastric resistance was improved by increasing oil and wax contents as well as sonication time, pH, and carrier content (P < 0.05). Average daily gain of broiler chickens fed diet supplemented with choline chloride (CC or ECC) was increased compared to those fed negative control diet during starter period (P < 0.05). The serum concentration of low-density lipoprotein-cholesterol, triglyceride, and cholesterol were decreased in birds fed diet supplemented with choline chloride (CC or ECC; P < 0.05). The results showed that ECC with no hygroscopic property might be an alternative to CC without negative effect on performance of broiler chickens

Ultrasonic intensification as a tool for enhanced microbial biofuel yields

peer-reviewedUltrasonication has recently received attention as a novel bioprocessing tool for process intensification in many areas of downstream processing. Ultrasonic intensification (periodic ultrasonic treatment during the fermentation process) can result in a more effective homogenization of biomass and faster energy and mass transfer to biomass over short time periods which can result in enhanced microbial growth. Ultrasonic intensification can allow the rapid selective extraction of specific biomass components and can enhance product yields which can be of economic benefit. This review focuses on the role of ultrasonication in the extraction and yield enhancement of compounds from various microbial sources, specifically algal and cyanobacterial biomass with a focus on the production of biofuels. The operating principles associated with the process of ultrasonication and the influence of various operating conditions including ultrasonic frequency, power intensity, ultrasonic duration, reactor designs and kinetics applied for ultrasonic intensification are also described

Renal oxidative stress status and histology in gentamicin nephrotoxicity: The effects of antioxidant vitamins

Background: In recent publications, several mechanisms have been implicated in gentamicin (GM) nephrotoxicity. Reactive oxygen species have been proposed as one of the causative factors of the drug renal side effects. This study was designed to evaluate the protective effects of the antioxidant vitamins against GM-mediated nephropathy in insitu isolated rat kidneys. Methods: Male Sprague-Dawley rats were randomly assigned to one of the following groups of seven rats: Group 1 (control) was tyrode perfused kidneys. Group 2 (GM), 200µg/ml gentamicin was added to the perfusate. Group 3 (GM + Vit C), the same as group 2 but vitamin C (200 mg/L) was added to the drinking water for 3 days and 100 mg/L to the perfusate. Group 4 (GM + Vit E), the same as group 2 but vitamin E (100 mg/100 g BW, ip) was injected 12 h before experiments. Group 5 (GM + Vit C + Vit E) the same as group 2 but Vit E and C were co-administered (same as Group 3 &amp; 4). Urinary N-acetyle-B-D-glucosaminidas (NAG) and renal cortex superoxide dismutase (SOD) levels were measured and tissue histological evaluations were performed. Results: Gentamicin caused a significant nephrotoxicity demonstrated by increase in urinary NAG. Decline in SOD contents were observed comparing to controls. Vit C or Vit E inhibited the gentamicin-induced increased releases of NAG into urine but did not show a significant effect on the SOD levels. Conclusion: Co-administration of VitC&amp;E significantly prevented the GM nephrotoxicity demonstrating by preservation of SOD levels and prevention of increase in urinary enzyme activities. Histological studies of renal tissues provided additional evidences for protective effects of antioxidant vitamins. We concluded that moderate doses of Vit C &amp; E have protective effects in gentamicin nephrotoxicity and co-administration of these vitamins have additional beneficial effects

Resistance of Microencapsulated Fish Oil in the Rumen and Its Effect on Gas Production and Rumen Degradability

Resistance of microencapsulated fish oil (MFO) in the rumen and its effects on fermentability of nutrients in the rumen was studied in 3 experiments. The key parameter in these studies was the amount of oil released from the microcapsules and their effects on gas production and rumen degradability in comparison with unprotected fish oil (FO). In the first experiment the effect of rumen and abomasum pH on disintegration of MFO and amount of fish oil released was investigated. In the second experiment effects of MFO on in vitro gas production and rumen fermentation kinetics was undertaken and in the third experiment in vitro Batch culture was used in order to estimate the effect of MFO on rumen degradability. Experimental treatments in the first experiment were 1) simple Microcapsules 2) tannic acid treated Microcapsules and 3) Ca2+ treated Microcapsules. In the second experiment or gas production study 2 kinds of basal diet including the forage diet (dry alfalfa) and the complete diet (forage to concentrate with ratio of 60:40) with 8 treatments for each experimental diet: including; 1) the control (without supplement), 2) 4% fish oil, 3) 12% whey protein concentrate and 4% fish oil, 4) 12% whey protein concentrate and 1.2% tannic acid, 5) 12% whey protein concentrate, 4% fish oil and 1.2% tannic acid, 6) 16% simple microcapsules 7) 17.2% tannic acid treated Microcapsules and 8) 17.2% Ca2+treated microcapsules were used. In the third experiment dry forage used as basal diet with 6 experimental treatments including; 1) the control (without supplement), 2) 4% fish oil, 3) 12% whey protein concentrate and 4% fish oil, 4) 16% simple microcapsules 5) 17.2% tannic acid treated microcapsules and 6) 17.2% Ca2+ treated microcapsules with 24h incubation time. In the first experiment the amount of oil released of microcapsules in rumen were 74, 7 and 12% and in abomasum were 74, 59 and 67% for simple, tannic acid and Ca2+ treated microcapsules respectively. Resistance of tannic acid treated microcapsules in the rumen and abomasum was significantly better than other treatments. In gas production experiment for both diets, the tannic acid led to significantly higher gas production in comparison with other treatments. In batch culture in vitro experiment oil the amount of oil released from microcapsules were 78.72, 13.52 and 26.2% in simple, tannic acid and Ca2+treated microcapsules respectively. DM degradability was not affected by fish oil in tannic acid treated microcapsules (P>0.05). DM degradability was significantly higher in tannic acid and Ca2+ treated microcapsules in comparison with the unprotected fish oil. The results showed that microencapsulation of fish oil with the suitable ingredients should led to better performance in case of animal performances. It can be concluded that the desirable dairy products in from of fatty acids are achievable by microcapsulation method similar to what was undertake in these experiments