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The quality of zein (Z)- and zein-tannic acid (ZTA)-coated guavas was monitored throughout 12 days of storage. Coated fruit showed lower changes in terms of visual appearance, chlorophyll contents and color. Weight loss, softening, and changes in soluble solids were also decreased by the coatings. The respiration peak as well as H2O2 and superoxide dismutase activity peaks were delayed by the coatings, and the ethylene production was reduced. So, the results were consistent with a slowed down ripening of guavas by the coatings, which was probably related to lowered oxygen permeability of guava skin. ZTA coating was more effective than Z to reduce weight loss, softening, color changes, ethylene production, and oxidative stress. The higher efficiency of ZTA coating was ascribed to zein crosslinking, which probably resulted in decreased gas permeability, promoting lower respiration rates and lower ROS production, slowing down the ripening process, and extending guava stability.

Corn zein is a predominatly hydrophobic protein, forming films with relatively good water resistance. Tannic acid, especially in its oxidized form, is supposed to cross-link proteins including zein, which may be explored to further enhance the water resistance of zein films. The effects of different contents (0-8 wt%) of unoxidized and oxidized tannic acid (uTA and oTA, respectively) on the properties of zein films at different pH values (4-9) were studied, according to central composite designs.; Results: Increasing tannic acid contents and pH values resulted in decreased water solubility and increased tensile strength and modulus of films. The presence of tannic acid provided the films with a yellowish color and increased opacity. Paired t-tests indicated that oTA films presented higher tensile strength, lower water vapor permeability and lower water solubility than uTA films.; Conclusion: Higher tannic acid contents and pH values resulted in films with better overall physical properties, which might be ascribed to cross-linking, although the films were still not water resistant. The resulting films have potential to be used for food packaging and coating applications. © 2017 Society of Chemical Industry.; © 2017 Society of Chemical Industry.

Polysaccharides have been used in several studies to form films and coatings to be used as packaging materials (or to complement packaging materials) for foods. The incorporation of nanofillers such as montmorillonite (MMT) has been suggested to improve the barrier and mechanical properties of biomaterials. Films from starch and cashew tree gum (CTG) were developed according to a central composite design with two variables: MMT concentration and sonication time. MMT concentrations of 5–10 g/100 g increased tensile strength and elastic modulus, while higher MMT concentrations impaired those properties. The moisture barrier has been favored by MMT, while transparency and elongation have been impaired by the nanofiller. Sonication favored strength and modulus, probably because of a better MMT dispersion. Starch-CTG coatings with or without MMT were applied to cashew nut kernels. Coated kernels presented reduced moisture absorption during 120 days of storage (especially those coated with the nanocomposite coating), indicating that the coatings could decrease the texture changes of kernels. Moreover, the oxidation rates during storage were similarly decreased by both coatings.

Hookworms are parasitic nematodes that cause anemia and intestinal infections in dogs, especially with large worm burdens. However, the serum protein profile of this parasitological disease is still poorly understood. The present study was design to evaluate 80 asymptomatic dogs (age; 8 months–2 years) to detect the presence of the hookworm thin-shelled, morulated eggs in faeces using faecal flotation and to evaluate the serum protein fractions determined by means of sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). Forty dogs had an elevated quantity of eggs in faeces (+++) (PD) and 40 dogs were healthy (HD). Infected dogs showed significant increases for IgG estimated concentrations (PD 1.79 ± 0.8 g/dL and HD 1.44 ± 0.72 g/dL, p = 0.04), for ceruloplasmin estimated concentrations (PD 19 ± 15 mg/dL and HD 5 ± 3.5 mg/dL, p = 0.0001), for alpha 1-acid glycoprotein estimated concentrations (PD 31.4 ± 17.9 mg/dL and HD 13.5 ± 12.1 mg/dL, p = 0.0001) and for a non-identified protein of 23 kDa estimated concentrations (PD 641.5 ± 194.9 mg/dL and HD 519.8 ± 197.9 mg/dL, p = 0.007). Dogs with hookworm infection showed significant differences in the serum protein profile when compared to healthy animals.

In the present study, it was evaluated the susceptibility of prostatic lesions in male adult rats exposed to Di-N-butyl-phthalate during fetal and lactational periods and submitted to MNU plus testosterone carcinogenesis protocol. Pregnant females were distributed into four experimental groups: CN (negative control); CMNU (MNU control); TDBP100 (100 mg/kg of DBP); TDBP500 (500 mg/kg of DBP). Females from the TDBP groups received DBP, by gavage, from gestation day 15 (GD15) to postnatal day 21 (DPN21), while C animals received the vehicle (corn oil). CMNU, TDBP100, and TDBP500 groups received a single intraperitoneal injection of MNU (50 mg/kg) on the sixth postnatal week. After that, testosterone cypionate was administered subcutaneously two times a week (2 mg/kg) for 24 weeks. The animals were euthanized on PND220. Distal segment fragments of the ventral (VP) and dorsolateral prostate (DLP) were fixed and processed for histopathological analysis. Protein extracts from ventral prostate were obtained, and western blotting was performed to AR, ERα, MAPK (ERK1/2), and pan-AKT. Stereological analysis showed an increase in the epithelial compartment in TDBP100 and TDBP500 compared to CN. In general, there was increase in the incidence of inflammation and metaplasia/dysplasia in the DBP-treated groups, mainly in DLP, compared to CN and CMNU. Proliferation index was significant higher in TDBP500 and PIN (prostatic intraepithelial neoplasia) was more frequent in this group compared to CMNU. Western blot assays showed an increase in the expressions of AR and MAPK (ERK1/2) in the TDBP100 compared to CN, and ERα and AKT expressions were higher in the TDBP500 group compared do CN. These results showed that different doses of DBP during prostate organogenesis in Wistar rats could increase the incidence of premalignant lesions in initiated rats inducing distinct biological responses in the adulthood. © 2015 Wiley Periodicals, Inc. Environ Toxicol 31: 1185-1195, 2016.

This study was conducted to evaluate the influence of cellulose whiskers (CW) from cotton linter and sonication on physical properties of glycerol-plasticized tilapia gelatin films produced by casting technique. The tensile strength and elastic modulus of the films have been improved by the addition of CW, while elongation tended to be impaired by CW loading. The barrier to water vapor has also been improved by the whiskers, and the film transparency has been unaffected. The sonication improved modulus, elongation, and transparency of the films, probably by enhancing CW dispersion on the nanocomposite films, and maybe by inducing some conformational changes on the gelatin matrix. FTIR spectroscopy study on films revealed some gelatin conformational changes induced by cellulose whiskers.

Corn zein is a predominatly hydrophobic protein, forming films with relatively good water resistance. Tannic acid, especially in its oxidized form, is supposed to cross-link proteins including zein, which may be explored to further enhance the water resistance of zein films. The effects of different contents (0-8 wt%) of unoxidized and oxidized tannic acid (uTA and oTA, respectively) on the properties of zein films at different pH values (4-9) were studied, according to central composite designs.Increasing tannic acid contents and pH values resulted in decreased water solubility and increased tensile strength and modulus of films. The presence of tannic acid provided the films with a yellowish color and increased opacity. Paired t-tests indicated that oTA films presented higher tensile strength, lower water vapor permeability and lower water solubility than uTA films.Higher tannic acid contents and pH values resulted in films with better overall physical properties, which might be ascribed to cross-linking, although the films were still not water resistant. The resulting films have potential to be used for food packaging and coating applications. © 2017 Society of Chemical Industry.

Animals are believed to be homeostatic by maintaining relatively constant body nutrient content independently of changes in diet. Phosphorus (P) is one of the most important elements for fishes as Loricariids, which are covered with armor-like bony plates. These species are expected to maintain nutrient homeostasis, however, in environments with low P availability they can be P-limited. The hypothesis of this study is that P concentration in body composition of an herbivorous fish, Hypostomus jaguribensis, does not change in environments with different availability of this nutrient. We conducted this study in two locations of the Curu river basin in Brazil, which differed in their nutrient concentrations: one was ultraoligotrophic and the other mesotrophic, as determined by total phosphorous concentrations and chlorophyll a in the water. We found significant differences in the body P content of the fish from the two sites: Hypostomus jaguribensis from the ultraoligotrophic site showed higher body P content, higher body weight and condition factor. This suggests that the ultraoligotrophic site is a more favorable environment for this species. The body P content was higher in intermediate sizes (between 12 and 14 cm in the ultraoligotrophic site and between 11 and 13 cm in the mesotrophic site), which can be related to biological characteristics such as the need to accumulate nutrients at the beginning of the reproductive period. Our study did not find support for strict homeostasis in this high-P demand fish species.

Properties of glycerol-plasticised cassava starch–carnauba wax emulsion films were studied as functions of carnauba wax/starch (CW/S) ratios. Increases in CW concentrations improved elongation, but impaired tensile strength and elastic modulus, suggesting a plasticising effect by CW and/or the emulsifier. CW reduced water solubility of the films and decreased their water vapour permeability (WVP) up to CW/S ratios of 0.15–0.20, probably because of the decreased water solubility. Higher CW concentrations resulted in increased WVP, possibly due to starch matrix loosening. The opacity imparted by high CW concentrations in films could compromise some applications. The Tg of starch and the expected CW effects on it were not evidenced by DSC thermograms, but CW seems to have affected starch crystallisation, maybe by forming complexes with amylose and/or amylopectin