Room temperature storage of myrtle (Eugenia gracillima Kiaersk.) tropical juice: Effects of physical and chemical preservation methods.

Tropical fruit juices produced from native fruits have been widely marketed by small agribusinesses in the Brazilian semiarid region, necessitating a deeper understanding of the impact of preservation methods on quality parameters. This study aimed to prepare myrtle (Eugenia gracillima Kiaersk.) tropical juice and investigate the effects of physical preservation (90 °C for 60 s) and chemical preservation (potassium sorbate and sodium benzoate) methods. Tropical juice formulations were evaluated after preparation and every 15 days during 60 days of storage in high-density polyethylene bottles at room temperature (25 ± 2 °C). Microbiological parameters, optical microscopy, physicochemical and bioactive parameters, antioxidant capacity, and color parameters were determined. Heat-treated tropical juice showed low counts of all microbiological parameters, but optical microscopy revealed the presence of filamentous fungi after 60 days of storage. Combined use of potassium sorbate and sodium benzoate effectively prevented the development of total yeasts and molds up to 28 days of storage. Bioactive compounds in myrtle pulp contribute to storage stability, mainly total phenolics, estimated at 855.86 mg gallic acid equivalents 100 g-1. The results suggest that it is possible to harness the economic and agroindustrial potential of E. gracillima Kiaersk. fruits for the production of tropical juices, but it is recommended that other technologies be explored, such as aseptic processing or the combined use of physical and chemical methods.

Brazilian bentonite/MgO composites for adsorption of cationic and anionic dyes.

Industrial effluents, especially those containing dyes, have become the main cause of contamination of water resources. In this context, Brazilian bentonite/MgO composites, with excellent adsorptive properties, were prepared and investigated for their effectiveness in removing cationic and anionic dyes from aqueous solutions. The new adsorbents were obtained using Brazilian bentonites and MgO using the mechanochemical method followed by heat treatment (at 700 °C for 4 h). Different characterization techniques were used for the chemical, mineralogical, thermal, surface, and morphological analysis of the raw clays and the composites. The experimental adsorption isotherms were quantified under different conditions of initial concentration, contact time, pH, adsorbent dosage, and temperature variation to interpret the adsorption mechanism of the crystal violet (CV) and Congo red (CR) dyes. The modeling results were obtained from the empirical Sips equation and Pseudo Second Order (PSO) kinetics, indicating that the adsorption of molecules is a heterogeneous phenomenon that occurs in a monolayer on the surface (ns > 1), with the adsorption rate determined by chemisorption. The composites showed the best removal efficiency performance compared to the raw bentonites, with an increase of 12% for the CV dye and 46% for the CR dye. In addition, the qmax values obtained were 423.02 mg/g and 479.86 mg/g (AM01). This research underscores the potential of Brazilian bentonite/MgO composites as a promising solution for the removal of cationic and anionic dyes from water, offering hope for future applications in the field of environmental engineering and materials science.

Beverage of Brazil Nut and Bocaiuva Almond Enriched with Minerals: Technological Quality and Nutritional Effect in Male Wistar Rats.

The objective of this work was to evaluate the properties of beverages formulated with Brazil nuts (Bertholletia excelsa Bonpl) and bocaiuva almonds (Acrocomia aculeata (Jacq.) Lodd. Ex Mart.). Five beverages were developed with Brazil nut, bocaiuva almond, and water (m/m/v), as follows: (i) NB, nut:water, 1:10; (ii) AB, almond:water, 1:10; (iii) NAB1, 1:0.1:10, nut:almond:water; (iv) NAB5, nut:almond:water, 1:0.5:10; and (v) NAB10, nut:almond:water, 1:1:10. The physicochemical, chemical, technological, and microbiological parameters were evaluated. After heat treatment (HT) and enrichment with minerals, the beverages that demonstrated stability in these characteristics were tested in a biological assay. The physical and biochemical parameters of male Wistar rats were evaluated after administering beverages for 28 days. HT decreased the total phenolic content and the antioxidant activity; however, it guaranteed microbiological safety. Mineral supplementation changed the colors and increased the pH values of the beverages. After the beverages were administered, the Wistar rats in the (i) NB group showed decreases in retroperitoneal adipose tissue, total cholesterol, and triglycerides; (ii) those in the AB group exhibited decreased triglycerides contents; and (iii) those in the NAB10-group presented decreased liver weights. The beverages evaluated in this study demonstrate a protective effect against risk factors such as fat accumulation in the liver, retroperitoneal adipose tissue, and hypercholesterolemia.

Experimental Infection and the Effects of Temperature on the Pathogenicity of the Infectious Spleen and Kidney Necrosis Virus in Juvenile Nile Tilapia (Oreochromis niloticus).

The infectious spleen and kidney necrosis virus (ISKNV) is one of the most important emerging viral pathogens for Nile tilapia (Oreochromis niloticus) farming. While prevalent worldwide, it has recently been detected in Brazil. However, despite the importance of the virus and the affected fish species, there are no scientific data on the effects of water temperature on disease pathogenesis in Nile tilapia. In the present study, we conducted two trials using juvenile Nile tilapia over a 15-day period. In trial 1, an experimental infection model was developed based on the intraperitoneal inoculation of active viral homogenates (4.3 × 104 virus fish-1), while control fish were similarly inoculated with inactivated viral homogenates. In trial 2, the fish were maintained at different water temperatures (26, 28, 30, 32, and 34 °C) and then infected with ISKNV. For virus detection, kidney and spleen samples were collected and analyzed by qPCR. Our results show that the disease was successfully reproduced in experimental conditions with active homogenates, with the first signs of the disease appearing on the third day after infection. In addition, a significant reduction in mortality was observed in the groups maintained at higher temperatures (>30 °C). This suggests that a treatment of the disease with non-lethal hyperthermia can be used to control the symptoms and mortality of ISKNV-infected Nile tilapia juveniles.

Impact of cyclic and continuous dry heat modification on the structural, thermal, technological, and in vitro digestibility properties of potato starch (Solanum tuberosum L.): A comparative study.

Dry heat treatment (DHT) has been demonstrated as a viable method for starch modification, offering benefits due to its environmentally friendly process and low operational costs. This research modified potato starch using different DHT conditions (continuous-CDHT and cyclic-RDHT), with durations ranging from 3 to 15 h and 1 to 5 cycles, at 120 °C. The study investigated and compared the structural, thermal, pasting, and morphological properties of the treated samples to those of untreated potato starch, including in vitro digestibility post-modification. DHT altered the amylose content of the biopolymer. X-ray diffraction patterns transitioned from type B to type C, and a decrease in relative crystallinity (RC%) was observed. Morphological changes were more pronounced in starches modified by RDHT. Paste viscosities of both CDHT and RDHT-treated starches decreased significantly, by 61.7 % and 58.1 % respectively, compared to native starch. The gelatinization enthalpy of RDHT-treated starches reduced notably, from 17.60 to 16.10 J g-1. Additionally, starch digestibility was impacted, with cyclic treatments yielding a significant increase in resistant starch content, notably an 18.26 % rise. These findings underscore the efficacy of dry heat in enhancing the functional properties of potato starch.

Influence of Pulsed Arc Parameters on the Tig Welding Process for the Stainless Steel Duplex UNS S31803.

The influence of parameters involved in the pulsed electric arc, used as an energy source in the tungsten inert gas (TIG)-mediated welding of Duplex UNS S31803 stainless steel, to attend the manufacture of flexible pipes for the extraction of oil and gas is presented. A fundamental part in the manufacturing process of flexible pipelines is the welding of these strips so that corresponding TIG welds will be subjected to the same process and work conditions. Therefore, it is necessary to maintain the same properties in the welded regions. Covering the effects of each parameter of the pulsed electric arc such as peak and base current as welds, cyclic ratio, and pulsation frequency is a desirable endeavor. The final objective is the mitigation of problems that have a great impact on production, such as weld breakage during the conformation of the strip in the process and test failures. With this, tensile, bending, and ferrite percentage tests were performed on 12 samples that qualified as satisfactory in the visual aspect. A minimum tensile strength of 734.57 MPa and a maximum of 775.77 MPa were obtained where all values found are above the tensile strength limit of the base material of 620 MPa. With the completion of the study, it is possible to understand not only the response of the process to each parameter but also the tendency when changing them. Moreover, it is possible to explore the possibility of guiding the changes to achieve results about the visual aspect and the mechanical properties of the welded material.

Histomorphometric evaluation, SEM, and synchrotron analysis of the biological response of biodegradable and ceramic hydroxyapatite-based grafts: from the synthesis to the bed application.

This study aimed to analyze the physicochemical and histological properties of nanostructured hydroxyapatite and alginate composites produced at different temperatures with and without sintering and implanted in rabbit tibiae. Hydroxyapatite-alginate (HA) microspheres (425-600 µm) produced at 90 and 5 °C without (HA90 and HA5) or with sintering at 1000 °C (HA90S and HA5S) were characterized and applied to evaluate thein vitrodegradation; also were implanted in bone defects on rabbit's tibiae (n= 12). The animals were randomly divided into five groups (blood clot, HA90S, HA5S, HA90, and HA5) and euthanized after 7 and 28 d. X-ray diffraction and Fourier-transform infrared analysis of the non-sintered biomaterials showed a lower crystallinity than sintered materials, being more degradablein vitroandin vivo. However, the sinterization of HA5 led to the apatite phase's decomposition into tricalcium phosphate. Histomorphometric analysis showed the highest (p< 0.01) bone density in the blood clot group, similar bone levels among HA90S, HA90, and HA5, and significantly less bone in the HA5S. HA90 and HA5 groups presented higher degradation and homogeneous distribution of the new bone formation onto the surface of biomaterial fragments, compared to HA90S, presenting bone only around intact microspheres (p< 0.01). The elemental distribution (scanning electron microscope and energy dispersive spectroscopy andµXRF-SR analysis) of Ca, P, and Zn in the newly formed bone is similar to the cortical bone, indicating bone maturity at 28 d. The synthesized biomaterials are biocompatible and osteoconductive. The heat treatment directly influenced the material's behavior, where non-sintered HA90 and HA5 showed higher degradation, allowing a better distribution of the new bone onto the surface of the biomaterial fragments compared to HA90S presenting the same level of new bone, but only on the surface of the intact microspheres, potentially reducing the bone-biomaterial interface.

BlueShaper: un nuevo sistema multialeación para la instrumentación mecanizada en endodoncia: comunicación breve / BlueShaper: a new multialloy system for mechanized instrumentation in endodontics: brief communication

El objetivo de esta comunicación es describir y analizar el sistema BlueShaper para la preparación quirúrgica mecaniza- da de los conductos radiculares. El sistema dispone de un set básico de 4 limas: Z1, Z2, Z3 y Z4, con un D0 de 0,14 mm, 0,17 mm, 0,19 mm y 0,25 mm respectivamente y conicidad variable que oscila entre el 2 y 10 %. La lima Z1 posee una aleación Pink, que le confiere mayor resistencia a la torsión y una gran capacidad de corte. Las limas Z2, Z3 y Z4 presentan una aleación Blue que aumenta la resistencia a la fatiga cíclica e incrementa su flexibilidad. Para conductos radiculares más amplios se incluyen, además, las limas Z5, Z6 y Z7. La empresa comer- cializa conos de gutapercha BlueShaper que se corresponden con las limas Z3, Z4, Z5, Z6 y Z7. El sistema de limas mul- tialeación Blue Shaper podría considerarse como un nuevo aporte clínico para la preparación mecánica de los conductos radiculares (AU)

The aim of this communication was to describe and analyze the BlueShaper system for the mechanized surgical preparation of root canals. The system has a basic set of 4 files: Z1, Z2, Z3 and Z4, with 0.14 mm, 0.17 mm, 0.19 mm and 0.25 mm DO respective- ly, and variable conicity ranging between 2 and 10 %. Z1 file has a Pink alloy, which gives it greater resistance to torsion and great cutting capacity. The Z2, Z3 and Z4 files feature a Blue alloy that increases resistance to cyclic fatigue and increases their flexibility. For larger root canals, the Z5, Z6 and Z7 files are also included. The company supplies specific BlueShaper ́s gutta-percha cones for Z3, Z4, Z5, Z6 and Z7 files. The BlueShaper multialloy file system could be consid- ered as a new clinical contribution for the mechanical prepa- ration of root canals (AU)

Evaluation of cyclic and torsional fatigue resistance of several heat-treated reciprocating nickel-titanium instruments.

This study investigated the cyclic fatigue and torsional resistance of Unicone Plus (UCP 25.06), Unicone (UC 25.06), Reciproc Blue (RB 25.08) and Wave One Gold (WOG 25.07) performed at body temperature (35° ± 1°C). Time and number of cycles to fracture (NCF), as well as torque and angular deflection were recorded. Fractured surfaces were evaluated by scanning electron microscopy (SEM). Data were analysed using one-way ANOVA and Holm-Sidak's tests for multiple comparison. The RB had a significantly higher time to fracture, followed by the WOG and UCP (p < 0.05). Regarding the NCF, there was no significantly difference between RB and WOG (p > 0.05). UC presented highest torque values and the lowest angular deflection (p < 0.05). SEM analysis demonstrated typical failures features in both cyclic and torsional fatigue tests. Overall, UC had the lowest time, NCF and angular deflection at fracture. RB presented the highest time to fracture and angular deflection values.

BlueShaper: un nuevo sistema multialeación para la instrumentación mecanizada en endodoncia. Comunicación breve / BlueShaper: a new multialloy system for mechanized instrumentation in endodontics. Brief communication

Resumen El objetivo de esta comunicación es describir y analizar el sistema BlueShaper para la preparación quirúrgica mecanizada de los conductos radiculares. El sistema dispone de un set básico de 4 limas: Z1, Z2, Z3 y Z4, con un D0 de 0,14 mm, 0,17 mm, 0,19 mm y 0,25 mm respectivamente y conicidad variable que oscila entre el 2 y 10 %. La lima Z1 posee una aleación Pink, que le confiere mayor resistencia a la torsión y una gran capacidad de corte. Las limas Z2, Z3 y Z4 presentan una aleación Blue que aumenta la resistencia a la fatiga cíclica e incrementa su flexibilidad. Para conductos radiculares más amplios se incluyen, además, las limas Z5, Z6 y Z7. La empresa comercializa conos de gutapercha BlueShaper que se corresponden con las limas Z3, Z4, Z5, Z6 y Z7. El sistema de limas multialeación BlueShaper podría considerarse como un nuevo aporte clínico para la preparación mecánica de los conductos radiculares.

Abstract The aim of this communication was to describe and analyze the BlueShaper system for the mechanized surgical preparation of root canals. The system has a basic set of 4 files: Z1, Z2, Z3 and Z4, with 0.14 mm, 0.17 mm, 0.19 mm and 0.25 mm DO respectively, and variable conicity ranging between 2 and 10 %. Z1 file has a Pink alloy, which gives it greater resistance to torsion and great cutting capacity. The Z2, Z3 and Z4 files feature a Blue alloy that increases resistance to cyclic fatigue and increases their flexibility. For larger root canals, the Z5, Z6 and Z7 files are also included. The company supplies specific BlueShaper´s gutta-percha cones for Z3, Z4, Z5, Z6 and Z7 files. The BlueShaper multialloy file system could be considered as a new clinical contribution for the mechanical preparation of root canals.

Assessment of torsion resistance of glide path rotary instruments

NiTi endodontic instruments for glide path are the most susceptible to fractures inside the root canal, mainly as a result of high torsional stress. Objective: The present study investigated the resistance to torsion and angular deflection of instruments destined for the glide path: ProGlider #16.02; T-File #17.02 and the MK Life #16.02. Materials and methods: Thirty rotating NiTi glide path instruments (n=10) with 25mm lengths were selected. The torsion test was performed based on ISO 3630-01 (1992). Three millimeters from the tip of the instruments, it was attached to a small load cell by a lever arm connected to the torsion shaft. Torsional strength and angular deflection were evaluated. Fracture surfaces were examined by scanning electron microscopy with magnifications of 1000x and 5000x in the cross section, and 50x in the lateral section. Statistical analysis was performed using the Kruskal-Wallis H test, followed by the Down's post hoc test. Results: The ProGlider instrument showed greater torsional strength (p<0.05) compared to the T-File (p<0.05) and MK Life (p<0.05), respectively. However, the T-File showed greater angular deflection (p<0.05) than the other groups tested. Conclusion: It can be concluded that the ProGlider instrument presented greater torque for the fracture, while the T-File instrument presented greater angular deflection.

Heat-resistant and biofilm-forming Escherichia coli in pasteurized milk from Brazil.

Escherichia coli harboring a transmissible locus of stress tolerance (tLST) and the ability to form biofilms represent a serious risk in dairy production. Thus, we aimed to evaluate the microbiological quality of pasteurized milk from two dairy producers in Mato Grosso, Brazil, with a focus on determining the possible presence of E. coli with heat resistance (60 °C/6 min), biofilm-forming potential phenotypes and genotypes, and antimicrobial susceptibility. For this, fifty pasteurized milk samples from producers named A and B were obtained for 5 weeks to investigate the presence of Enterobacteriaceae members, coliforms, and E. coli. For heat resistance, E. coli isolates were exposed to a water bath at 60 °C for 0 and 6 min. In antibiogram analysis, eight antibiotics belonging to six antimicrobial classes were analyzed. The potential to form biofilms was quantified at 570 nm, and curli expression by Congo Red was analyzed. To determine the genotypic profile, we performed PCR for the tLST and rpoS genes, and pulsed-field gel electrophoresis (PFGE) was used to investigate the clonal profile of the isolates. Thus, producer A presented unsatisfactory microbiological conditions regarding Enterobacteriaceae and coliforms for weeks 4 and 5, while all samples analyzed for producer B were contaminated at above-the-limit levels established by national and international legislation. These unsatisfactory conditions enabled us to isolate 31 E. coli from both producers (7 isolates from producer A and 24 isolates from producer B). In this way, 6 E. coli isolates (5 from producer A and 1 from producer B) were highly heat resistant. However, although only 6 E. coli showed a highly heat-resistant profile, 97% (30/31) of all E. coli were tLST-positive. In contrast, all isolates were sensitive to all antimicrobials tested. In addition, moderate or weak biofilm potential was verified in 51.6% (16/31), and the expression of curli and presence of rpoS was not always related to this biofilm potential. Therefore, the results emphasize the spreading of heat-resistant E. coli with tLST in both producers and indicate the biofilm as a possible source of contamination during milk pasteurization. However, the possibility of E. coli producing biofilm and surviving pasteurization temperatures cannot be ruled out, and this should be investigated.

Comparative study of four extraction methods of fructans (agavins) from Agave durangensis: Heat treatment, ultrasound, microwave and simultaneous ultrasound-microwave.

Agavins (fructans from the agave plant) are used for their technological and prebiotic properties in developing functional foods. In this study, four extraction methods were evaluated: ultrasound (U), microwave (M), simultaneous ultrasound-microwave (UM), and heat treatment (HT). Isomers with a degree of polymerization (DP) > 10, as well as a significant concentration of fructooligosaccharides (FOS) were identified. The yield obtained by UM (72%) was similar to the other methods; however, the extraction time was shorter (5 min). In U, M, and HT the yields were 86, 76, and 85% in 35, 30, and 180 min, respectively. In addition, FTIR spectra showed evidence of regions corresponding to fatty acids and carbohydrates. Therefore, using UM to obtain agavins is a more ecological and faster process.

Effect of plasma and heat treatments on orange juice quality / Efeito de plasma e tratamento térmico na qualidade do suco de laranja

Heat treatment is used in the orange juice industry to neutralize the action of pathogenic microorganisms. However, it can reduce the nutritional value of the juice. Thus, our study assessed the cold plasma treatment as an alternative method against Escherichia coli and Candida albicans in 'Lima' orange juice. Both, plasma and heat treatments, reduced the amount of E. coli in the juice, inactivating 16.72 and 100%, respectively. Plasma did not inactivate C. albicans, but heat treatment inactivated 100%. Plasma and heat treatment increased Hue angle and luminosity (more yellowish juice). Plasma reduced vitamin C, carotenoids, and polyphenols content, while increased flavonoids. Heat treatment reduced the carotenoid content. However, neither heat nor plasma treatment altered the antioxidant activity. The plasma treatment reduced the intensity of color (chroma), the soluble solids content and the acidity ratio, total sugars, and the vitamin C content of juice compared to the heat-treated and control juices. Plasma-treated juice showed increased levels of yellow flavonoids, total phenolics and antioxidant activity until the 12th day of storage.

O tratamento térmico é utilizado na indústria de suco de laranja para neutralizar a ação de microrganismos patogênicos. No entanto, pode reduzir o valor nutricional do suco. Assim, o estudo avaliou o tratamento com plasma frio como método alternativo contra Escherichia coli e Candida albicans em suco de laranja 'Lima'. Ambos os tratamentos, plasma e calor, reduziram a quantidade de E. coli no suco, inativando 16.72 e 100%, respectivamente. O plasma não inativou C. albicans, mas o tratamento térmico inativou 100%. Plasma e tratamento térmico aumentaram o ângulo Hue e a luminosidade do suco (tom mais amarelo). O plasma reduziu o conteúdo de vitamina C, carotenóides e polifenóis, enquanto aumentou os flavonóides. O tratamento térmico reduziu o teor de carotenóides. No entanto, nem o calor nem o tratamento com plasma alteraram a atividade antioxidante. O tratamento com plasma reduziu a intensidade da cor (croma), o teor de sólidos solúveis e a razão de acidez, açúcares totais e o teor de vitamina C do suco em comparação com os sucos tratados termicamente e controle. O suco tratado com plasma apresentou maiores teores de flavonóides amarelos, fenólicos totais e atividade antioxidante até o 12º dia de armazenamento.

Poly(o-methoxyaniline) Chain Degradation Based on a Heat Treatment (HT) Process: Combined Experimental and Theoretical Evaluation.

Poly(o-methoxyaniline) emeraldine-salt form (ES-POMA) was chemically synthesized using hydrochloric acid and subjected to a heat treatment (HT) process for 1 h at 100 °C (TT100) and 200 °C (TT200). The HT process promoted a progressive decrease in crystallinity. The Le Bail method revealed a decomposition from tetrameric to trimeric-folded chains after the HT process. The unheated POMA-ES presented a globular vesicular morphology with varied micrometric sizes. The heat treatment promoted a reduction in these globular structures, increasing the non-crystalline phase. The boundary length (S) and connectivity/Euler feature (χ) parameters were calculated from the SEM images, revealing that ES-POMA presented a wide distribution of heights. The TT100 and TT200 presented a narrow boundary distribution, suggesting smoother surfaces with smaller height variations. The UV-VIS analysis revealed that the transition at 343 nm (nonlocal π → π*) was more intense in the TT200 due to the electronic delocalization, which resulted from the reduced polymer chain caused by the HT process. In addition to the loss of conjugation, counter ion withdrawal reduced the ion-chain interaction, decreasing the local electron density. This result shows the influence of the chlorine counter ions on the peaks position related to the HOMO → LUMO transition, since the π → polaron transition occurs due to the creation of the energy states due to the presence of counter ions. Finally, the electrical conductivity decreased after the HT process from 1.4 × 10-4 S.cm-1 to 2.4 × 10-6 S.cm-1 as result of the polymer deprotonation/degradation. Thus, this paper proposed a systematic evaluation of the POMA molecular structure and crystallite size and shape after heat treatment.

Blanching Effect on the Quality and Shelf-Life Characteristics of Fresh Cowpea Grains [Vigna unguiculata (L.) Walp.].

The high perishability of fresh cowpeas impairs its commercialization. Thus, this study aims to determine the temperature-time binomial for blanching fresh cowpea [Vigna unguiculata (L.) Walp] by evaluating the effects of heat treatment and kinetic behavior on the peroxidase (POD) activity and on the physical characteristics (firmness, color, mass gain). A factorial design (3 × 6) with temperature (70, 80, and 90 °C) and time (1, 2, 4, 6, 8, and 10 min) was implemented. Physicochemical, microbiological, and enzymatic (POD) changes, in addition to photographic monitoring, were evaluated throughout the storage period (4.90 °C). With regard to the effects of the independent variables and the first-order kinetic model, it was determined that 70 °C for 4 min of blanching maintained and/or improved the physical characteristics of the raw material. The pH and the acidity of the blanched fresh cowpea changed little during the storage period; the microbiological load and POD activity reduced with blanching and remained stable until the eighth day of storage, and provided an increase of 5 days in shelf-life under refrigeration when compared to non-blanched. Blanching is shown as an alternative for improving fresh cowpeas, favoring an economic increase in production with guaranteed quality and safety attributes.

Fatty Acids Profile and Healthy Lipids Indices of Native Mexican Guajolote Meat Treated to Two Heat Treatments.

Meat is a complex food with a structured nutritional composition that makes it an essential component of the human diet. In particular, the meat of native guajolote that is traditionally raised in natural conditions is an important dietary source of proteins of high biological value for the rural population of Mexico. The study aimed to evaluate fatty acids (FAs) profile and nutritional indices of breast and leg meat of native guajolote subjected to two heat treatments. For the study, a total of sixty muscle samples (30 breast meat and 30 leg meat) from adult male native guajolotes were used. The FA profile and nutritional indices were evaluated in raw meat (control) and meat subjected to two heat treatments (boiled and baked). The heat treatments, independently of the type of muscle, increased (p ≤ 0.05) the concentration of saturated (SFA) and monounsaturated FA (MUFA); in contrast, polyunsaturated FA (PUFA) decreased. Likewise, the dietary FA index, which has a negative hypercholesterolemic effect, and the atherogenic index increased in guajolote meat from the effect of the heat treatments, while the essential and undesirable hypercholesterolemic FA indices decreased. In conclusion, heat treatments increase the content of SFA and MUFAs in breast and leg meat of native guajolote. Boiling or baking the meat deteriorates PUFAs but increases the nutritional indices. The present investigation would provide valuable information for the guajolote meat product processing.

The Importance of Heating Unit Operations in the Food Industry to Obtain Safe and High-Quality Products.

Civilization has begun around 3,500 BCE in Mesopotamia and the realization by people that they could manipulate food to preserve it, through sun drying, fermentation, freezing in the snow, or cooking by fire, was an important factor for the nomadic humans to start settling. Food by nature is subject to spoilage and the application of any kind of preservation method enables storage and weighted consumption. Throughout human history, many techniques have been developed and improved such as heat treatment, drying, freezing, extraction, mixing and the use of preservatives, among others. In the food industry of the modern world, each technique is implemented through sequential steps, known as unit operations. This opinion paper presents an overview of the main heating unit operations used in the food industry, highlighting their benefits to converting raw materials into palatable products with high quality and safe for consumption. Examples are presented to illustrate how several food products available in the market were submitted only to physical transformations based on scientific knowledge. However, there is a range of intensity in physical processing and the applied energy level depends on the nature of the food, target microorganism, storage conditions, type of packaging, and desired shelf-life. The importance of food safety is stressed since processed foods have been criticized for confusion between nutritious values and processing steps. There are still many challenges to the food industry to design the process in optimal conditions for food quality and with less environmental impacts and novel thermal and non-thermal technologies have been studied and implemented.

Alternativa rápida de extracción de ADN en quistes de Acanthamoeba para uso en el laboratorio de análisis clínicos / Rapid DNA extraction alternative in cysts of Acanthamoeba for use in clinical analysis laboratory

Resumen El objetivo del estudio fue comparar la extracción de ADN de quistes de Acanthamoeba sp. con un método disponible comercialmente y cuatro no comerciales utilizando tratamiento térmico y ultrasonido para la amplificación por una reacción en cadena de la polimerasa (PCR) convencional, reduciendo tiempos de preparación y extracción de las muestras, como una herramienta para el diagnóstico en el laboratorio clínico. Se utilizó una cepa de Acanthamoeba, genotipo T4, cultivada en agar no nutritivo. Los quistes para analizar, en tres períodos de enquistamiento, se almacenaron a temperatura ambiente. Se extrajo ADN mediante cinco métodos: pretratamiento térmico, ultrasonido y combinaciones de ellos. La PCR se llevó a cabo utilizando cebadores específicos JDP1/JDP2. La concentración y pureza del ADN extraído con los protocolos evaluados revelaron diferencias estadísticamente significativas (p<0,0001). El método E (comercial), el A (térmico) y el B (ultrasonido) lograron los mejores rendimientos en la amplificación del fragmento específico de Acanthamoeba sp. por la PCR convencional.

Abstract The objective of the study was to compare the DNA extraction of Acanthamoeba sp. cysts with a commercially available method and four non-commercial ones, with heat and ultrasound treatment that allows amplification by conventional polymerase chain reaction (PCR), reducing sample preparation and extraction times, such as a tool for diagnosis in the clinical laboratory. To this aim, a strain of Acanthamoeba T4 grown on non-nutrient agar was used. Plates with cysts at three different encystation times were stored at room temperature until the study was carried out. DNA was extracted with five methods that included pretreatments (thermal and ultrasound) or combinations of them. PCR was performed using specific primers JDP1/JDP2. Concentration and purity of DNA revealed statistically significant differences (p<0.0001) between methods. Method E (commercial), method A (thermal) and B (ultrasound) got the best yields in amplifying the specific fragment of Acanthamoeba sp. by conventional PCR.

Resumo O objetivo do estudo foi comparar a extração de DNA de cistos de Acanthamoeba sp. com um método comercialmente disponível e quatro não comerciais utilizando tratamento térmico e ultrassom para amplificação por reação em cadeia da polimerase (PCR) convencional, reduzindo os tempos de preparo e extração das amostras, como ferramenta para o diagnóstico no laboratório clínico. Foi utilizada uma cepa de Acanthamoeba, genótipo T4, cultivada em ágar não nutritivo. Os cistos para analisar foram armazenados em temperatura ambiente, correspondendo a três períodos de encistamento. O DNA foi extraído por cinco métodos: pré-tratamento térmico, ultrassom e combinações deles. A PCR foi realizada usando iniciadores específicos JDP1/JDP2. A concentração e a pureza do DNA extraído com os protocolos avaliados revelaram diferenças estatisticamente significativas (p<0,0001). Os métodos E (comercial), A (térmico) e B (ultrassom) alcançaram os melhores rendimentos na amplificação do fragmento específico de Acanthamoeba sp. por PCR convencional.

Effect of A Clinical-Replicable Cooling Protocol on the Cyclic Fatigue Resistance of Heat-Treated Nickel-Titanium Instruments.

Introduction: The aim of this study was to evaluate the bending and cyclic fatigue resistance of Wave One Gold (WOG) and X1 Blue (X1B) instruments when tested at body temperature (36°C ± 1°C) with and without subjected to an alloy cooling protocol. Materials and Methods: A total of sixty instruments (n=30) were tested. Forty instruments (n=20) were randomly selected and divided into two groups: body temperature (BT; n=20) and body temperature with cooling protocol (CP; n=20). Cyclic fatigue test was performed until fracture in a conventional stainless-steel device with water bath equipment to simulate body temperature. CP group instruments were subjected to 5 seconds of spray cooling every 30 seconds. Time to fracture was recorded in seconds. Resistance to bending at an angle of 45 degrees was evaluated using twenty instruments (n=10). Fractured surfaces were examined under scanning electron microscopy (SEM). Statistical analysis was performed at a 5% significance level. Results: There was no difference in the cyclic fatigue resistance between instruments in BT groups (P>0.05). Cooling protocol significantly increased the cyclic fatigue resistance of X1B instruments (P=0.0003) and WOG instruments (P=0.0003). Results: WOG instruments had a significantly lower cyclic fatigue resistance compared to X1B instruments in CP group (P=0.0001). There were no significant differences between the values of resistance increase presented by the instruments after cooling (P>0.05). Bending test presented no statistically significant differences between the tested instruments (P>0.05). Both instruments in both groups showed typical features of cyclic fatigue behavior under SEM. Conclusions: X1 Blue #25.06 and WaveOne Gold #25.07 instruments presented similar cyclic fatigue resistance. The investigated clinical-replicable cooling protocol improved the cyclic fatigue resistance of the tested instruments, with X1 Blue #25.06 presenting a greater cyclic fatigue resistance after cooling. Both instruments presented a similar bending capacity.