Ethanol production by Bacillus stearothermophilus.

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Prospects for treating foods with cold atmospheric gas plasmas

In this review the potential applications of cold atmospheric gas plasmas are presented with particular reference to the problems of contamination of foods by biological agents. In addition to the accidental contamination of food, the very real threat arising from the deliberate contamination of the human food chain is also considered. The evidence that has been gained for the efficacy of cold plasmas in inactivating a wide range of biological agents is briefly surveyed. This is followed by an examination of previous work in which various types of foodstuffs have been successfully treated using cold gas plasmas. The need to demonstrate that the quality attributes of treated foods is not adversely affected is stressed. Finally, the role which gas plasmas may have in decontaminating food processing equipment is considered

Hepatoprotective potency of Lagenandra toxicaria and Ariopsis peltata against CCl4 induced liver fibrosis in Wistar rats

Lagenandra toxicaria (LT) and Ariopsis peltata (AP) belongs to the family Araceae. LT is being traditionally used to cure bilious symptoms and wound healing. AP leaves are edible and the rhizome has medicinal value. With such a wide range of medicinal applications, it's essential to scientifically authenticate traditional usage and find the plant's bioactive components. Here, we have examined the anti-inflammatory and hepatoprotective potency of these plant extracts. The in-vivo liver fibrosis was induced in Wistar male rats using CCl4 and was treated with various concentrations of the methanol and water extracts of the plant rhizomes. In the in-vitro anti-inflammatory assay, LT methanol extract showed 42 % protection at 600 mg/ml which is higher than the other extracts. Among the AP and LT extracts, the 600 mg/kg methanol extract of LT treated rats showed a decreased (p<0.05) serum alanine/aspartate aminotransferase and total bilirubin levels. The plant extract brought about an amelioration of CCl4 induced pathological effects and a significant reduction in the severity of inflammation, fatty metamorphosis, necrosis and liver fibrosis. Overall, the results suggest that LT rhizome could be effective in the treatment of liver fibrosis. It is possible that this is related to the presence of anti-inflammatory and antioxidant chemicals such as 9-octadecenamide, flavonoids and phenols in the extract

A comparison of low intensity UV-C and high intensity pulsed polychromatic sources as elicitors of hormesis in tomato fruit

Post-harvest hormetic treatment of mature green tomato fruit (Solanum lycopersicum cv. Mecano) with high intensity pulsed polychromatic light (HIPPL) significantly delayed ripening to levels comparable to those achieved using a conventional low intensity UV-C (LIUV) source. A 16 pulse HIPPL treatment reduced the ΔTCI (tomato colour index) by 50.1 % whilst treatment with a LIUV source led to a reduction of 43.1 %. Moreover, the 16 pulse treatment also induced disease resistance in the fruit to Botrytis cinerea with a 41.7 % reduction in disease progression compared to a 38.1 % reduction for the LIUV source. A single 16 pulse HIPPL treatment was found to significantly reduce disease progression on both mature green and ripe fruit with a 28.5 % reduction on ripe fruit in comparison to 13.4 % for the LIUV treatment. It is shown here that delayed ripening and disease resistance are local responses in side treated tomato fruit for both LIUV and HIPPL treatments. Finally, utilising a 16 pulse HIPPL treatment would reduce treatment times from 370 s for LIUV sources to 10 s per fruit - a 97.3 % reduction

Preharvest high-intensity, pulsed polychromatic light and low-intensity UV-C treatments control Botrytis cinerea on lettuce (Lactuca sativa)

Hormetic treatments using high-intensity, pulsed polychromatic light (HIPPL) and low-intensity UV-C (LIUV) can control Botrytis cinerea on lettuce (Lactuca sativa) in a controlled environment. For the cv. Temira, 48 pulses of HIPPL significantly reduced mean disease progression (26%), while 0.64kJ/m2 of LIUV gave reductions of 27%. No LIUV or HIPPL treatment significantly reduced disease progression for cv. Amica. A 0.98kJ/m2 dose of LIUV and 24 pulses of HIPPL, however, reduced mean disease progressions (25% and 15%) when compared to the control. Phytotoxicity was observed at 48 and 72 pulses of HIPPL for Amica and Temira, respectively. LIUV caused phytotoxicity on both cvs. above 0.98kJ/m2 but at a reduced incidence for Temira. Both technologies delivered a similar level of disease control on cv. Temira and may provide a residue-free alternative to the chemical control of plant pathogens. HIPPL treatments, however, were achieved in 15s and may prove to be a more commercially feasible alternative to LIUV with a treatment duration of 32s

Epidemiology of burns at the University Teaching Hospital of Kigali, Rwanda

Introduction: Burns are the fourth most common type of injury presenting to the emergency department in Rwanda. However, there is little data on the epidemiology of burn patients, which is needed to inform public health measures for burn prevention. This study aimed to describe the characteristics and outcomes of burn patients presenting to the Emergency of the University Teaching Hospital Kigali.Methods: This single-center prospective study evaluated patients with burn injuries presenting at CHUK emergency between 1 June and 31 December 2019. Data on demographics, burn characteristics, burn management, disposition and patient outcomes were collected, stored in Excel and analyzed descriptively using SPSS 24. Results: Of the 96 patients enrolled; (58.3%) were male. The median age was 32.7 years. Most patients were pediatric (70.9%), with one to five-year-olds being the most affected age group. Scalding was the most common cause of burn at (71.9%). Most burns were accidental (95.8%) and superficial dermal in degree (72.9%). The mean time between injury and presentation was 18.1 hours. There were 12 mortalities (12.5%) within the 30 days post-injury, with scald injuries as the most frequent cause of mortality. Higher mortality was significantly associated with increased body surface area affected (p = 0.001).Conclusion: Children between the ages of one and five years are the most affected by burns and scalding is the most common burn etiology. Public health measures should aim to prevent burn injuries in the pediatric population. This study was approved by the University of Rwanda /CMHS Institutional Review Board (IRB) No 136/CMHS IRB/ 2019

Applications of cold atmospheric gas plasmas for microbial decontamination in the food industry

The last 20 years have seen the emergence of a novel technology capable of generating gas plasmas in the open air and at temperatures that are only slightly above ambient. These so-called Cold Atmospheric Plasmas (CAP) have characteristics that render them particularly suitable for a variety of applications in the food industry. In this presentation prevalence will be given to microbial decontamination. In particular, understanding the mechanism of microbial inactivation is important as if the most lethal plasma species can be identified, it may prove possible to ‘tune’ the plasmas so as to maximise their production. Preliminary investigations undertaken by our group have gone some way to addressing this issue. One of the most promising applications of CAP is in the treatment of fresh uncooked foods, and results are presented here attesting to the efficacy of plasmas in inactivating a range of micro-organisms at or near the surface of fruits. The possibilities for using plasmas for destruction of allergens and spongiform encephalopathies are also considered

Synthesis, Electrical Conductivity, and Dielectric Behavior of Polyaniline/V 2

Conducting polymer composites of polyaniline/vanadium pentaoxide PANI/V2O5 (with different initial weight percentage of V2O5) has been synthesized by in situ polymerization method. DC conductivity of compressed pellets has been analyzed in the temperature range 300–550 K and was found to increase with V2O5 doping. This increase in conductivity is mainly due to band conduction. It has also been observed that the dielectric constant and dielectric loss increase with the level of doping of V2O5 but remain independent of the frequency (50 KHz–1 MHz). X-ray diffraction pattern shows some order of crystallinity of composites due to interaction of polyaniline with V2O5. UV-visible spectroscopy shows an increase in the optical band gap with doping

Modeling the inactivation kinetics of Bacillus subtilis spores by nonthermal plasmas

The inactivation performances of different nonthermal plasmas are often compared with each other in terms of their decimal reduction values, typically obtained by linearizing selected segments of their inactivation curves. However, this approach is subjective and can result in uncertainties in the prediction of this parameter. To overcome this, in this paper, the application of models capable of describing inactivation curves in their entirety is considered. The authors employ the Baranyi and Weibull models, both commonly used for microbial inactivation by heat. An empirical model based on a third-order polynomial to seek greater accuracy is further proposed. Using these three inactivation models, predictions of decimal reduction values for 11 plasma inactivation studies of Bacillus subtilis spores are obtained and compared with their reported values. Although the agreement obtained between these different approaches is generally fair, the current practice of segmented linearization is shown to be overly simplistic. A rigorous model is therefore critical to capture the essentially nonlinear character of plasma inactivation kinetics and hence allow for an objective comparison of the performances of similar biocidal nonthermal plasmas

Cold atmospheric gas plasma disinfection of chicken meat and chicken skin contaminated with Listeria innocua

Gas plasmas generated at atmospheric pressure and ambient temperatures offer a possible decontamination method for poultry products. The efficacy of cold atmospheric gas plasmas for decontaminating chicken skin and muscle inoculated with Listeria innocua was examined. Optimization of operating conditions for maximal bacterial inactivation was first achieved using membrane filters on which L. innocua had been deposited. Higher values of AC voltage, excitation frequency and the presence of oxygen in the carrier gas resulted in the greatest inactivation efficiency, and this was confirmed with further studies on chicken muscle and skin. Under optimal conditions, a 10 s treatment gave > 3 log reductions of L. innocua on membrane filters, an 8 min treatment gave 1 log reduction on skin, and a 4 min treatment gave > 3 log reductions on muscle. These results show that the efficacy of gas plasma treatment is greatly affected by surface topography. Scanning electron microscopy (SEM) images of chicken muscle and skin revealed surface features wherein bacteria could effectively be protected from the chemical species generated within the gas plasma. The developments in gas plasma technology necessary for its commercial application to foods are discussed