Inactivation of hepatitis A virus, feline calicivirus, and Tulane virus on Formica coupons using ultraviolet light technologies.

Contaminated fomites can lead to hepatitis A virus (HAV) and human norovirus (HuNoV) disease outbreaks. Improved decontamination methods that are user-friendly, cost-effective, and waterless are being researched for sustainability. Traditional ultraviolet light (UV-C) technologies though effective for surface decontamination have drawbacks, using mercury lamps, that pose user-safety risk and environmental hazards. Therefore, UV-C light emitting diode (LED) systems are being designed for delivering required antiviral doses. The objective of this research was to determine the ability of UV-C LED (279 nm) systems to inactivate HuNoV surrogates, feline calicivirus (FCV-F9) and Tulane virus (TV), and HAV on Formica coupons in comparison to UV-C (254 nm) systems. FCV-F9 (∼6 log PFU/mL), TV (∼7 log PFU/mL), or HAV (∼6 log PFU/mL) at 100 µL were surface-spread on sterile Formica coupons (3 × 3 cm2), air-dried, and treated for up to 2.5 min with both systems. Each experiment was replicated thrice. Recovered infectious plaque counts were statistically analyzed using mixed model analysis of variance. FCV-F9, TV, and HAV showed D10 values of 23.37 ± 0.91 mJ/cm2, 16.32 ± 3.6 mJ/cm2, and 12.39 ± 0.70 mJ/cm2 using 279 nm UV-C LED, respectively and D10 values of 9.97 ± 2.44 mJ/cm2, 6.83 ± 1.13 mJ/cm2 and 12.40 ± 1.15 mJ/cm2, respectively with 254 nm UV-C. Higher 279 nm UV-C LED doses were required to cause HuNoV surrogate reduction than 254 nm UV-C, except similar doses with both systems were needed for HAV inactivation on Formica surfaces. It remains critical to measure UV intensity of optical sources and optimize exposure times for desired log reduction on surfaces.

Effect of UV Irradiation on the Nutritional Quality and Cytotoxicity of Apple Juice.

UV-C irradiation operating at 254 nm wavelength on the polyphenolic and vitamin contents of apple juice including cytotoxicity analysis was studied. UV doses ranging from 0 to 150 mJ·cm-2 were selected for the treatments. Polyphenols (catechin, epicatechin, chlorogenic acid, and phloridzin) and vitamins (riboflavin, thiamine hydrochloride, pyridoxal hydrochloride, pyridoxine, pyridoxamine dihydrochloride, cyanocobalamin, choline chloride, biotin, niacin, and niacinamide) were chemically profiled. It was observed that UV treatment of apple juice at disinfection doses caused minor reductions (p < 0.05) in the concentrations of two main polyphenols (i.e., chlorogenic acid and epicatechin). In contrast, significant (p < 0.05) decreases in vitamin concentrations were observed (p < 0.05). The irradiated juice was evaluated for cytotoxic effects. The irradiated apple juice showed no cytotoxic effects on normal intestinal cells, and both irradiated and nonirradiated samples are significantly comparable in inhibiting the growth of human colon cancer cells. Overall, these results indicated that UV-C treatment of apple juice neither significantly degraded polyphenols nor generated cytotoxic compounds.

Effect of ultrasound processing on anthocyanins and color of red grape juice.

Grape juice samples were sonicated with processing variables of amplitude level (24.4-61.0microm) and treatment time (0-10min) at a constant frequency of 20kHz and pulse durations of 5s on and 5s off. A full factorial experimental design with regression modeling was employed to investigate the main effects of amplitude level and treatment time on anthocyanins and color parameters. Significant effects of sonication on major anthocyanins cyanidin-3-O-glucosides (CA), malvanidin-3-O-glucosides (MA) and delphinidin-3-O-glucosides (DA), color values (L*, a*, b*) and color index (CI) were observed. Prediction models were found to be significant (p<0.05) with low standard errors and high coefficients of determination (R(2)). Model predictions for critical quality parameters of anthocyanins (CA; MA; DA), color values (L*, a*, b*), TCD and CI inactivation were closely correlated to the experimental results obtained. Significant retention of anthocyanin content in grape juice was observed for CA (97.5 %); MA (48.2 %) and DA (80.9%) during sonication. CI and other color combinations (L*a*b*, L*a*/b* and L*b*/a*) were found to be strongly correlated with anthocyanin content. This study shows that sonication could be employed for as a preservation technique for fruit juice processing where anthocyanin retention is desired.

Anthocyanins and color degradation in ozonated grape juice.

Grape juice samples were ozonated with processing variables of ozone concentration (1.6-7.8% w/w) and treatment time (0-10 min). Effects of processing variables on grape juice color values (L, a and b) and anthocyanins were determined. The changes in lightness (L) values and total color difference (TCD) values were fitted well to zero-order kinetics whereas, a and b followed first-order kinetics. Three major anthocyanins were observed in the grape juice namely cyanidin-3-O-glucoside (Cy3Gl, 133.9 mg/L), delphinidin-3-O-glucoside (Dy3Gl, 21.4) and malvidin-3-O-glucoside (My3Gl, 3.2mg/L). Significant reductions in anthocyanin content were observed during ozonation. During ozonation Cy3Gl was found to be stable compared to Dy3Gl and My3Gl. Changes in Cy3Gl were fitted well to the fraction conversion model. The results presented in this study indicate that both color and anthocyanin content are significantly affected during ozone processing. Thus, the effects of ozonation on the grape juice should be considered by processors prior to its adoption as a preservation technique.

Anthocyanin and ascorbic acid degradation in sonicated strawberry juice.

Strawberry juice samples were sonicated at amplitude levels ranging from 40 to 100% at a constant frequency of 20 kHz for treatment times (2-10 min) and pulse durations of 5 s on and 5 s off. Sonication was found to reduce anthocyanin and ascorbic acid contents by 3.2 and 11%, respectively, at the maximum treatment conditions. Response surface methodology (RSM) based on a two-factor, five-level central composite design was employed to determine the effect of amplitude level and treatment time on anthocyanins (P3G), ascorbic acid (AA) content, and color values (L*, a*, and b*). The model predictions for the selected nutritional and quality parameters were closely correlated to the experimental results. RSM was demonstrated to be an effective technique to model the effect of sonication on strawberry juice quality while minimizing the number of experiments required.

[Possible environmental factors in oral pathology]. / Unii factori de mediu posibili în patologia orala.

A study has been undertaken on 540 patients working in three different industry branches. As a result there have been established correlations between different forms of oral pathology and factors susceptible to be aetiologic.

[Variations in the intraoral electromotive force in the electrotherapy of the upper extremities]. / Variatii ale fortei electromotoare intraorale în electroterapia extremitatii cefalice.

We tested the intraoral microwaves under applied electrotherapy in cephalic neuralgia. The tests have been undertaken on 40 patients divided in 4 groups, according to the nature of the metallic components of the prosthetic appliances. There have been withdrawn practical conclusions regarding fixed prosthesis and the use of electrotherapy in the cephalic neuralgia.