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Purpose The transfer of soil sediments and phosphorus from terrestrial to aquatic systems is a common process in agricultural lands. The aims of this paper are to quantify the soil phosphorus availability and to characterize phosp...
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Purpose The transfer of soil sediments and phosphorus from terrestrial to aquatic systems is a common process in agricultural lands. The aims of this paper are to quantify the soil phosphorus availability and to characterize phosphorus forms in soil sediments as contaminant agents of waters as a function of anthropic pressures.
Materials and methods On three subwatersheds with different anthropic pressure, water and sediment samples were collected automatically in upstream and downstream discharge points in six rainfall events during the tobacco growing season. Phosphorus desorption capacity from soil sediments was estimated by successive extractions with anion exchange resins. First-order kinetic models were adjusted to desorption curves for estimating potentially bioavailable particulate phosphorus, desorption rate constant, and bioavailable particulate phosphorus. Results and discussion The amount of bioavailable particulate phosphorus was directly correlated with the iron oxide content. The value of desorption rate constant was directly related with the total organic carbon and inversely with the iron oxide contents. Phosphate ions were released to solution, on average, twice as rapidly from sediments collected in subwatersheds with low anthropic activity than from those ones of highly anthropic subwatersheds. Anthropic pressure on watershed can engender high sediment discharge, but these solid particles seem to present low phosphorus-releasing capacity to water during transport due to the evidenced high affinity between phosphorus and iron oxide from sediments. Conclusions Anthropic pressure was related with sediment concentration and phosphorus release to aquatic systems. While natural vegetation along streams plays a role on soil and water depuration, it is unable to eliminate the phosphorus inputs intrinsic to the agricultural-intensive systems. Recommendations and perspectives The contamination of water in watershed by phosphates is facilitated by the erosion process and the traditional tobacco cropping system. Urgent measures for erosion control must be adopted, in accordance to conformations of landscape and the local inhabitants' needs. Among them, those worth pointing out are the adoption of a conservation crop system, regeneration of riparian zone, and reduction of the phosphate doses added to soil for tobacco cultivation.
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Weeds host of root-knot nematodes (Meloidogyne spp.), parasites of important crop plants mainly in tropical and subtropical regions, enable them to maintain themselves or increase their abundance in soils. To evaluate the host sta...
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Weeds host of root-knot nematodes (Meloidogyne spp.), parasites of important crop plants mainly in tropical and subtropical regions, enable them to maintain themselves or increase their abundance in soils. To evaluate the host status of 31 weed species that commonly compete with crops, we experimentally inoculated them with 5000 eggs and second-stage juveniles (J2) of Meloidogyne enterolobii. Sixty days after inoculation, we measured several parameters related to infestation ability, including gall index (GI), number of eggs/g root, and reproduction factor (RF). About 77.4% (n = 24) of the weed species we assessed were susceptible (RF > 1) to M. enterolobii infestation: Acanthospermum australe, Amaranthus deflexus, Amaranthus hybridus, Amaranthus spinosus, Amaranthus viridis, Bidens pilosa, Bidens subalternans, Cardiospermum halicacabum, Commelina benghalensis, Euphorbia heterophylla, Galinsoga parviflora, Ipomoea grandifolia, Ipomoea nil, Ipomoea purpurea, Leonurus sibiricus, Nicandra physaloides,Polygonum hydropiperoides, Portulaca oleracea, Rhynchelytrum repens, Sida rhombifolia, Solanum americanum, Solanum sisymbriifolium, Solanumpseudocapsicum, and Talinumpaniculatum. In contrast, seven species were resistant (RF < 1) to M. enterolobii infestation: Conyza bonariensis, Cyperys rotundus, Digitaria horizontalis, Digitaria insularis, Eleusine indica, Raphanus raphanistrum, and Senecio brasiliensis. Management strategies to control M. enterolobii should identify susceptible weeds in crop fieldsand control these potential alternative hosts of the parasitic nematode.
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To evaluate total intravenous anesthesia with propofol alone or in combination with S(+)-ketamine in rabbits undergoing surgery. Prospective, randomized, blinded trial. Nine 6-month-old New Zealand white rabbits, weighing 2.5-3 kg...
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To evaluate total intravenous anesthesia with propofol alone or in combination with S(+)-ketamine in rabbits undergoing surgery. Prospective, randomized, blinded trial. Nine 6-month-old New Zealand white rabbits, weighing 2.5-3 kg. Animals received acepromazine (0.1 mg kgp#) and buprenorphine (20 og kgp#) IM, and anesthesia was induced with propofol (2 mg kgp#) and S(+)-ketamine (1 mg kgp#) IV. Rabbits received two of three treatments: propofol (0.8 mg kgp# minutep#) (control treatment, P), propofol (0.8 mg kgp# minutep#) + S(+)-ketamine (100 og kgp# minutep#) (PK100) or propofol (0.8 mg kgp# minutep#) + S(+)-ketamine (200 og kgp# minutep#) (PK200). All animals received 100% O during anesthesia. Heart rate, mean arterial pressure, hemoglobin oxygen saturation and respiratory rate were measured every 5 minutes for 60 minutes. Blood-gas parameters were measured at zero time and 60 minutes. Additional propofol injections, if necessary, and recovery time were recorded. An increase in heart rate was observed in P and PK200 up to 10 minutes after induction of anesthesia. Blood pressure decreased from baseline values during the first 10 minutes in P and PK200, and during the first 15 minutes and between 45 and 55 minutes in PK100. A reduction in respiratory rate was observed after 5 minutes in all treatments. Respiratory acidosis was observed in all treatments. Six (2.8) [median (interquartile range)] further propofol injections were necessary in P, which differed statistically from PK100 [1 (0.2)] and PK200 [2 (0.6)]. Recovery time was shorter in P compared with PK100 and PK200, being [7.5 minutes (4.11)], [17.5 minutes (10.30)], and [12 minutes (10.30)], respectively. S(+)-ketamine potentiates propofol-induced anesthesia in rabbits, providing better maintenance of heart rate. All of these techniques were accompanied by clinically significant respiratory depression.
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To evaluate total intravenous anesthesia with propofol alone or in combination with S(+)-ketamine in rabbits undergoing surgery. Prospective, randomized, blinded trial. Nine 6-month-old New Zealand white rabbits, weighing 2.5-3 kg...
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To evaluate total intravenous anesthesia with propofol alone or in combination with S(+)-ketamine in rabbits undergoing surgery. Prospective, randomized, blinded trial. Nine 6-month-old New Zealand white rabbits, weighing 2.5-3 kg. Animals received acepromazine (0.1 mg kgp#) and buprenorphine (20 og kgp#) IM, and anesthesia was induced with propofol (2 mg kgp#) and S(+)-ketamine (1 mg kgp#) IV. Rabbits received two of three treatments: propofol (0.8 mg kgp# minutep#) (control treatment, P), propofol (0.8 mg kgp# minutep#) + S(+)-ketamine (100 og kgp# minutep#) (PK100) or propofol (0.8 mg kgp# minutep#) + S(+)-ketamine (200 og kgp# minutep#) (PK200). All animals received 100% O during anesthesia. Heart rate, mean arterial pressure, hemoglobin oxygen saturation and respiratory rate were measured every 5 minutes for 60 minutes. Blood-gas parameters were measured at zero time and 60 minutes. Additional propofol injections, if necessary, and recovery time were recorded. An increase in heart rate was observed in P and PK200 up to 10 minutes after induction of anesthesia. Blood pressure decreased from baseline values during the first 10 minutes in P and PK200, and during the first 15 minutes and between 45 and 55 minutes in PK100. A reduction in respiratory rate was observed after 5 minutes in all treatments. Respiratory acidosis was observed in all treatments. Six (2.8) [median (interquartile range)] further propofol injections were necessary in P, which differed statistically from PK100 [1 (0.2)] and PK200 [2 (0.6)]. Recovery time was shorter in P compared with PK100 and PK200, being [7.5 minutes (4.11)], [17.5 minutes (10.30)], and [12 minutes (10.30)], respectively. S(+)-ketamine potentiates propofol-induced anesthesia in rabbits, providing better maintenance of heart rate. All of these techniques were accompanied by clinically significant respiratory depression.
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The influence of different concentrations of NaCl (2.5% and 1.75%), basic electrolyzed water (BEW), and ultrasound (US, 25 kHz, 159 W) on the quality of fresh sausages was studied. During storage at 5 ℃, TBARS, pH, Eh, aw, nitrou...
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The influence of different concentrations of NaCl (2.5% and 1.75%), basic electrolyzed water (BEW), and ultrasound (US, 25 kHz, 159 W) on the quality of fresh sausages was studied. During storage at 5 ℃, TBARS, pH, Eh, aw, nitrous pigments, and bacterial evolution were evaluated at three specific time intervals: 1d, 15d, and 30d. At the same time, the volatile compounds and sensory profile were specifically assessed on both the 1d and 30d. Notably, sausages with 1.75% NaCl and BEW displayed higher pH values (up to 6.30) and nitrous pigment formation, alongside reduced Eh (as low as 40.55 mV) and TBARS values (ranging from 0.016 to 0.134 mg MDA/ kg sample), compared to the 2.5% NaCl variants. Protein content ranged between 13.01% and 13.75%, while lipid content was between 18.23% and 18.86%, consistent across all treatments. Psychrotrophic lactic bacteria showed a significant increase in low-NaCl sausages, ranging from 5.77 to 7.59 log CFU/g, indicative of potential preservative benefits. The sensory analysis favored the TUSBEW70 treatment for its salty flavor on the 30th day, reflecting a positive sensory acceptance. The study highlights that employing US and BEW in sausage preparation with reduced NaCl content (1.75%) maintains quality comparable to higher salt (2.5%) counterparts. These findings are crucial for meat processing, presenting a viable approach to producing healthier sausages with reduced sodium content without compromising quality, aligning with consumer health preferences and industry standards.
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This study investigated the effect of a 50% reduction in sodium nitrite and the addition of nisin (200 mgAg) and different concentrations CO, 0.5%, 0.75%, and 1%) of jabuticaba peel extract (JPE) on the main attributes affected by...
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This study investigated the effect of a 50% reduction in sodium nitrite and the addition of nisin (200 mgAg) and different concentrations CO, 0.5%, 0.75%, and 1%) of jabuticaba peel extract (JPE) on the main attributes affected by this chemical additive in Bologna-type sausages. The modified treatments showed approximately 50% lower residual nitrite than the control throughout the storage (60 days at 4 ℃). The proposed reformulation did not affect the color (L*, a*, and b*), and the AE values (＜ 2) demonstrated high color stability during storage. Physicochemical (TBARS and volatile compounds) and sensory analyses performed to evaluate oxidative stability indicated that JPE exhibited antioxidant activity comparable to sodium nitrite. The microbiological quality of the reformulated products was similar to the control, but further studies should be conducted to assess the effect of this reformulation strategy on the growth of pathogenic microorganisms impacted by nitrite.
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A freeze-dried extract from the bark of mate branches (BMBE) containing high chlorogenic acids (CGA) content (30 g 100 g~(-1)) was produced. Then, chia oil was mixed with 7.5% BMBE and sonicated for 0, 10, and 20 min. Chia oil wit...
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A freeze-dried extract from the bark of mate branches (BMBE) containing high chlorogenic acids (CGA) content (30 g 100 g~(-1)) was produced. Then, chia oil was mixed with 7.5% BMBE and sonicated for 0, 10, and 20 min. Chia oil with or without the addition of BMBE was hydrogelled and used to produce buffalo burgers with 50% reduction in animal fat. CGA levels and the nutritional, oxidative, and sensory properties of the burgers were analyzed. A reduction of ～30% fat and an increase above 60% PUFA/SFA ratio was observed for the reformulated raw and cooked burgers. In addition, the Omega-6/Omega-3 PUFA ratio of the burgers decreased from 20.8 (raw) and 31.9 (cooked) to values lower than 2. The addition of BMBE enriched the burgers with CGA, preventing an increase in lipid oxidation caused by chia oil. The addition of BMBE-enriched hydrogelled chia oil not subjected to sonication did not affect the sensory properties of the burgers.
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Purpose - The aim of this study was to evaluate the effect of ultrasound (US) treatment on the postharvest of "Isabella" grapes and the consistency of the obtained results regarding the composition of anthocyanins in grape juice o...
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Purpose - The aim of this study was to evaluate the effect of ultrasound (US) treatment on the postharvest of "Isabella" grapes and the consistency of the obtained results regarding the composition of anthocyanins in grape juice over three successive harvest years using a combination of analytical techniques. Design/methodology/approach - Juices produced from "Isabella" grapes sonicated for different durations (3,5,7 and 10 min) were analysed. The grapes were harvested and sonicated in 2013,2014 and 2015, and each treated sample was stored for 1,3 and 5 days in order to verify the time necessary for the development of the US response. The juices were analysed through physicochemical analysis (total monomeric anthocyanins). The anthocyanin profiles were quantified and identified using high perfonnance liquid chromatography coupled to photodiode array and mass spectrometry detectors (HPLC-PDA-MSn). Findings - The results demonstrated the potential of US in improving the quality of grape juice. In all three harvests, it was observed that the treatments were effective in increasing the concentration of anthocyanins. For the 2013 harvest, the application of US for 5 min led to a 103% increase in juice pigments. However, the US response profile varied among the three harvests, indicating that the US effect was influenced by the ripening conditions of the fruit. In total, 33 anthocyanins were identified in the grape juice. For the first time, peonidin-3-p-coumaroyl glucoside-5-glucoside was identified in "Isabella" juice. Originality/value - The results of this study validated US treatment as a simple and effective physical method that can be used as an alternative technology for improving the general quality of products such as juice by increasing the pigment concentrations that are linked to the colour and antioxidant potential of drinks. Moreover, the results demonstrate that US treatment may be less effective in the case of a sample with distinct phenolic maturation.
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This study evaluated the reduction of cooking time of mortadellas using ultrasound (US, 25 kHz) and the effects on the oxidative and microbiological quality of the product. Three cooking conditions were studied: control, cooking t...
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This study evaluated the reduction of cooking time of mortadellas using ultrasound (US, 25 kHz) and the effects on the oxidative and microbiological quality of the product. Three cooking conditions were studied: control, cooking time traditionally adopted by the meat industry; TUS and TWUS: cooking with and without US application and 50% reduction of the traditional cooking time, respectively. The application of US did not increase the peroxide, conjugated dienes, and TEARS indices and did not accelerate the protein oxidation. In addition, no significant changes were observed in the color of the mortadellas subjected to ultrasonic-assisted cooking. TUS and control presented a similar mesophilic, psychrotrophic and lactic acid bacteria counts during storage. The ultrasonic-assisted cooking provided a faster increase and higher homogeneity in the internal temperature of the mortadellas. Therefore, the US can be considered a promising technology to improve the cooking process of mortadellas.
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The combination of high-power ultrasound (HPU) and bamboo fiber (BF) was investigated as a strategy to produce phosphate-free meat emulsions. The samples were made with the addition of 0 and 0.25% of alkaline phosphate and 0, 2.5,...
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The combination of high-power ultrasound (HPU) and bamboo fiber (BF) was investigated as a strategy to produce phosphate-free meat emulsions. The samples were made with the addition of 0 and 0.25% of alkaline phosphate and 0, 2.5, and 5% BF. Immediately after filling, the samples were sonicated for 0 or 27 min at normal mode, 25 kHz, 60% amplitude, and 20 ℃. The samples made with BF and without phosphate showed higher emulsion stability compared to the control made with phosphate. The addition of 2.5% BF effectively compensated for the texture changes due to the absence of phosphate. HPU improved the effect of BF on the texture of meat emulsions by increasing cohesiveness. No significant impact of HPU and BF was observed on the oxidative quality of the samples. However, the instrumental assays and the sensory evaluation demonstrated that the absence of phosphate increased the lipid oxidation of the samples from the beginning of storage.
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