39 research outputs found
Inactivation of Coronaviruses in food industry: The use of inorganic and organic disinfectants, ozone, and UV radiation
Currently there is a worldwide pandemic due to Covid-19, which has caused a great impact on humanity in social, economic, psychological aspects and unfortunately on health. Due to the risk that food can also be a medium to cause virus diseases, the procedures in the food industry safety programs must be revised; and, to be more specific, to disinfect Covid-19. Some effective disinfectants that have been proved to inactivate the coronavirus are: chlorine dioxide, sodium hypochlorite, quaternary compound, ozone and UV-C (shortwave ultraviolet light). In this review, some treatments used to inactivate a virus, with an emphasis to the coronavirus family, and other influenza viruses, are reported. It has been concluded that the coronavirus could be inactivated using free chlorine solutions at 30 mg/L, sodium hypochlorite 0.25 %, or Chlorine Dioxide (99% purity) diluted at 1/2.5 relation. Also, alcohol is an effective disinfectant at concentrations of 62 to 71% of ethanol. With respect to the use of the quaternary compound, it can be used at concentrations of 0.10%. Ozone is another promising disinfectant to inactivate the coronavirus and Covid-19. Doses of ozone between 10 to 20 ppm for 10 to 15 minutes are recommended to inactivate the coronavirus with 3.5 log10 reductions. However, a warning should be reported to the use of high doses of exposure because it can be a risk to human health. UV-C can inactivate the coronavirus at a value of 67 J/m2 by 1 to 30 minutes of exposure.Currently there is a worldwide pandemic due to Covid-19, which has caused a great impact on humanity in social, economic, psychological aspects and unfortunately on health. Due to the risk that food can also be a medium to cause virus diseases, the procedures in the food industry safety programs must be revised; and, to be more specific, to disinfect Covid-19. Some effective disinfectants that have been proved to inactivate the coronavirus are: chlorine dioxide, sodium hypochlorite, quaternary compound, ozone and UV-C (shortwave ultraviolet light). In this review, some treatments used to inactivate a virus, with an emphasis to the coronavirus family, and other influenza viruses, are reported. It has been concluded that the coronavirus could be inactivated using free chlorine solutions at 30 mg/L, sodium hypochlorite 0.25 %, or Chlorine Dioxide (99% purity) diluted at 1/2.5 relation. Also, alcohol is an effective disinfectant at concentrations of 62 to 71% of ethanol. With respect to the use of the quaternary compound, it can be used at concentrations of 0.10%. Ozone is another promising disinfectant to inactivate the coronavirus and Covid-19. Doses of ozone between 10 to 20 ppm for 10 to 15 minutes are recommended to inactivate the coronavirus with 3.5 log10Â reductions. However, a warning should be reported to the use of high doses of exposure because it can be a risk to human health. UV-C can inactivate the coronavirus at a value of 67 J/m2Â by 1 to 30 minutes of exposure
Serratia strains isolated from the rhizosphere of raulĂ ( Nothofagus alpina ) in volcanic soils harbour PGPR mechanisms and promote raulĂ plantlet growth
[EN] RaulĂ is one of the most emblematic tree species of the Chilean temperate forests. Due to the high quality wood,
this tree has been used for furniture and handicrafts manufacturing, which has positioned raulĂ as one of the
most important commercial timber species in Chile. Currently, the international market demands sustainable
production system for forest production, more specifically in plantlets production. In this regard, plant growthpromoting
rhizobacteria (PGPR) inoculants may enhance the growth and survival of plantlets in nurseries,
which means an increase in the effectiveness of replanting operations. Therefore, the aim of the present study
was to isolate, characterize and screen rhizosphere-associated bacteria with PGPR potential, isolated from raulĂ
that growth in volcanic soils in southern Chile. A total of 1,261 bacterial strains were isolated from different
volcanic soils. Out of 1,261 isolates, 100 were selected based on their high levels of indole acetic acid (IAA)
production. These isolates were then subjected to screening for 1-aminocyclopropane-1-carboxylic acid deaminase
activity, and their ability to fix nitrogen was determined. From the 100 selected isolates, 7 were chosen for
producing the highest amount of IAA to continue with genetic characterization based on their 16S rRNA gene
sequences. These 7 isolates were characterized as members of the Serratia genus and were used to develop
multi-strain inoculant mixtures. Later, a nursery study followed to determine the effect of inoculation with the
Serratia strains on the growth of RA88 raulĂ clone plantlets. The nursery experiment demonstrated that Serratia
strains have the potential to increase the root collar diameter, height, relative chlorophyll content, biomass and
nitrogen content of raulĂ plantlets. The study concluded, that Serratia strains have the potential to be used as
biofertilizers to increase plant growth in nursery conditions
Desarrollo y aplicaciĂłn de metodologĂas analĂticas para la determinaciĂłn de arsĂ©nico inorgánico en productos de la pesca
Tesis doctoral presentada para lograr el tĂtulo de Doctor por la Universidad de Valencia en 2000Se ha planteado como objetivo general de esta investigaciĂłn el desarrollo de metodologias analiticas para la determinaciĂłn de arsĂ©nico inorgánico en un amplio muestrario de productos pesqueros.
Los resultados se evaluaron desde el punto de vista medio-ambiental sanitario y toxicologico.
Para el cumplimiento de este objetivo general se han desarrollado metodologias para la determinacion de arsenico inorganico en aguas y productos pesqueros.
Dichas metodologias se han aplicado a un amplio muestrario de productos pesqueros del Estuario Guadalquivir y de productos de la pesca pertenecientes a un estudio de dieta total.
Los resultados obtenidos han permitido ponen de manifiesto la necesidad de regular los contenidos de arsenico en productos de la pesca en funciĂłn de sus contenidos de arsenico inorganico.Peer reviewe
Optimization of the solubilization, extraction and determination of inorganic arsenic [As(III)+As(V)] in seafood products by acid digestion, solvent extraction and hydride generation atomic absorption spectrometry
A method for the selective quantitative determination of inorganic arsenic [As(III) + As(v)] in seafood was developed. In order to do so, various procedures for the solubilization and extraction of inorganic arsenic quoted in the literature were tested. None provided satisfactory recoveries for As(III) and As(v) in real samples. Consequently, a methodology was developed which included solubilization with HCl and subsequent extraction with chloroform. The arsenic was solubilized in 9 mol 1(-1) hydrochloric acid. After reduction by hydrobromic acid and hydrazine sulfate, the inorganic arsenic was extracted into chloroform, back-extracted into 1 mol 1(-1) HCl, dry-ashed, and quantified by hydride generation-atomic absorption spectrometry (HG-AAS). The analytical features of the method are as follows: detection limit, 3.07 ng g(-1) As (fresh mass); precision (RSD), 4.0%; recovery, As(III) 99%, As(v) 96%. In the optimized conditions, other arsenic species-dimethylarsinic acid (DMA), arsenobetaine (AB), arsenocholine (AC) and tetramethylarsonium-ion (TMA(+))-were not co-extracted. However, different percentages of minor species were extracted with chloroform: monomethylarsonic acid (MMA) 100%, and trimethylarsine oxide (TMAO) 3-10%. Real samples and reference materials of seafood (DORM-1, DORM-2, TORT-2, CRM-278 and SRM-1566a) were analyzed. The analysis of DORM-1 provided an inorganic arsenic value of 124 +/- 4 ng g(-1) As, dry mass (dm), which is very close to the value obtained by other authors using high performance liquid chromatography -inductively coupled plasma-mass spectrometry (HPLC-ICP-MS) and ionic chromatography-hydride generation-atomic absorption spectrometry (IC-HG -AAS)
Optimization of the solubilization, extraction and determination of inorganic arsenic [As(III) + As(v)] in seafood products by acid digestion, solvent extraction and hydride generation atomic absorption spectrometry
A method for the selective quantitative determination of inorganic arsenic [As(III) + As(v)] in seafood was developed. In order to do so, various procedures for the solubilization and extraction of inorganic arsenic quoted in the literature were tested. None provided satisfactory recoveries for As(III) and As(v) in real samples. Consequently, a methodology was developed which included solubilization with HCl and subsequent extraction with chloroform. The arsenic was solubilized in 9 mol l-1 hydrochloric acid. After reduction by hydrobromic acid and hydrazine sulfate, the inorganic arsenic was extracted into chloroform, back-extracted into 1 mol l-1 HCl, dry-ashed, and quantified by hydride generation-atomic absorption spectrometry (HG-AAS). The analytical features of the method are as follows: detection limit, 3.07 ng g-1. As (fresh mass); precision (RSD), 4.0%; recovery, As(III) 99%. As(v) 96%. In the optimized conditions, other arsenic species - dimethylarsinic acid (DMA), arsenobetaine (AB), arsenocholine (AC) and tetramethylarsonium-ion (TMA+) - were not co-extracted. However, different percentages of minor species were extracted with chloroform: monomethylarsonic acid (MMA) 100%, and trimethylarsine oxide (TMAO) 3-10%. Real samples and reference materials of seafood (DORM-1, DORM-2, TORT-2, CRM-278 and SRM-1566a) were analyzed. The analysis of DORM-1 provided an inorganic arsenic value of 124 ± 4 ng g-1 As, dry mass (dm), which is very close to the value obtained by other authors using high performance liquid chromatography-inductively coupled plasma-mass spectrometry (HPLC-ICP-MS) and ionic chromatography-hydride generation-atomic absorption spectrometry (IC-HG-AAS)
Rapid and quantitative release, separation and determination of inorganic arsenic [As(III) plus As(V)] in seafood products by microwave-assisted distillation and hydride generation atomic absorption spectrometry
A precise, simple and rapid method is described for the determination of inorganic arsenic [As(iii)+As(v)] in seafood products. The inorganic species were isolated from the matrix by microwave-assisted distillation and determined by hydride generation atomic absorption spectrometry (HGAAS). The microwave and chemical parameters were optimized in order to obtain quantitative inorganic arsenic recoveries. The analytical features of the method are as follows: detection limit 10 ng g(-1) (dry mass) or 2 ng g(-1) (fresh mass); precision (RSD) 4%; recoveries 106 +/- 3% for As(iii) and 113 +/- 4% for As(v). Under the optimized conditions, arsenobetaine, arsenocholine and tetramethylarsonium ion added to samples of seafood were not distilled; however, minor species were distilled and were detected in various percentages: 109% monomethylarsonic acid; 11% dimethylarsinic acid; 0.2% trimethylarsine oxide. The concentrations expressed as arsenic contributed by these species would imply a mean overestimate of inorganic arsenic of about 24 ng g(-1) dry mass (dm). The concentrations of inorganic arsenic found in natural seafood samples ranged between 0.053 and 1.145 mu g g(-1) (dm) (mean moisture content 78%). The procedure was compared with an alternative methodology in which acid digestion-solvent extraction-HGAAS was used for the determination of inorganic arsenic. A Student's t-test for paired samples of the data obtained by the two methodologies showed no significant differences (P -value 0.66).Comisio´n Interministerial de Cienc´ıa y Tecnolog´ıa (CICyT), Project ALI96–051
Rapid and quantitative release, separation and determination of inorganic arsenic [As (III) + As(v)] in seafood products by microwave-assisted distillation and hydride generation atomic absorption spectrometry
A precise, simple and rapid method is described for the determination of inorganic arsenic [As(III) +As(v)] in seafood products. The inorganic species were isolated from the matrix by microwave-assisted distillation and determined by hydride generation atomic absorption spectrometry (HGAAS). The microwave and chemical parameters were optimized in order to obtain quantitative inorganic arsenic recoveries. The analytical features of the method are as follows: detection limit 10 ng g-1 (dry mass) or 2 ng g-1 (fresh mass); precision (RSD) 4%; recoveries 106±3% for As(III )and 113±4% for As(v). Under the optimized conditions, arsenobetaine, arsenocholine and tetramethylarsonium ion added to samples of seafood were not distilled; however, minor species were distilled and were detected in various percentages: 109% monomethylarsonic acid; 11% dimethylarsinic acid; 0.2% trimethylarsine oxide. The concentrations expressed as arsenic contributed by these species would imply a mean overestimate of inorganic arsenic of about 24 ng g-1 dry mass (dm). The concentrations of inorganic arsenic found in natural seafood samples ranged between 0.053 and 1.145 ÎĽg g-1 (dm) (mean moisture content 78%). The procedure was compared with an alternative methodology in which acid digestion-solvent extraction-HGAAS was used for the determination of inorganic arsenic. A Student's t-test for paired samples of the data obtained by the two methodologies showed no significant differences (P-value 0.66).The authors gratefully acknowledge the financial support of the ComisiĂłn Interministerial de Ciencia y TecnologĂa (CICyT), Project ALI96–0511, for which they are deeply indebted. O. Muñoz received a Research Personnel Training Grant from the Instituto de CooperaciĂłn Iberoamericana (ICI)
Determining the effect of different cooking methods on the nutritional composition of salmon (Salmo salar) and chilean jack mackerel (Trachurus murphyi) fillets.
The effect of four cooking methods was evaluated for proximate composition, fatty acid, calcium, iron, and zinc content in salmon and Chilean jack mackerel. The moisture content of steamed salmon decreased (64.94%) compared to the control (68.05%); a significant decrease was observed in Chilean jack mackerel in all the treatments when compared to the control (75.37%). Protein content in both salmon and Chilean jack mackerel significantly increased under the different treatments while the most significant decrease in lipids was found in oven cooking and canning for salmon and microwaving for Chilean jack mackerel. Ash concentration in both salmon and Chilean jack mackerel did not reveal any significant differences. Iron and calcium content only had significant changes in steaming while zinc did not undergo any significant changes in the different treatments. Finally, no drastic changes were observed in the fatty acid profile in both salmon and Chilean jack mackerel
Determination of inorganic arsenic [As(III)+As(V)] in water samples by microwave assisted distillation and hydride generation atomic absorption spectrometry
Inorganic arsenic was determined in samples of natural water from Region II of Chile, using a methodology consisting on microwave assisted distillation and hydride generation atomic absorption spectrometry (HG-AAS). The analytical features of the method are as follows: detection limit, 5 ÎĽg l-1; precision (RSD), 5%; and recovery, 93±3% for As(III) and 95±9% for As(V). The inorganic arsenic concentrations varied within the range 0.95-13.08 mg l-1. The concentrations of inorganic arsenic obtained by microwave assisted distillation and HG-AAS, compared with the concentrations of As(III)+As(V) obtained by anion exchange chromatography coupled to HG-AAS, showed no statistically significant differences. The use of microwave assisted distillation and HG-AAS provides a simple, inexpensive way of isolating inorganic arsenic from water matrices that may otherwise cause interferences if analysed directly by HG-AAS.We gratefully acknowledge the financial support of the ComisiĂłn Interministerial de CiencĂa y TecnologĂa (CICyT), Project ALI96-0511, for which we are deeply indebted. O. Muñoz received a Research Personnel Training Grant from the Instituto de CooperaciĂłn Iberoamericana (ICI)