Juan Ignacio Reguera

Universidad de Burgos, Burgos, Castille and León, Spain

Are you Juan Ignacio Reguera?

Claim your profile

Publications (9)14.69 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: Soil biodisinfection process is based on the biodegradation of incorporated organic amendments to the soil. Soil microorganisms are directly responsible for this decomposition, so the soil biodisinfection process stimulates the soil microbial population activity. These microbial populations increase also produces increased levels of exoenzymes in the soil. We used plant by-products from strawberry crop as biofumigant in different application rates (10, 20 and 40 g of biofumigant kg−1 of agricultural soil). Microbial changes during the soil biodisinfection process were tested from two approaches, microbial catabolic abilities (Biolog® Eco) and microbial counts. We made counts of aerobic, anaerobic, Pseudomonas sp. and aminocyclopropane-1-carboxylate (ACC) degrading populations during the soil biodisinfection process (at 0, 7 and 20 d). The highest metabolic activity of soil microorganisms was found under 10 g kg−1 of soil treatment. Anaerobic microbial population increased significantly (7 × 106 CFU g−1 of agricultural soil) in the 40 g biofumigant kg−1 assay. Counts were decreased when the application rates were reduced, but these counts were higher than control assay values. Aerobic, Pseudomonas sp. and ACC degrading microbial populations had not significant changes by the addition of organic matter amendments. These data indicate that the activity of anaerobic microbial growth was stimulated by soil biodisinfection process. The soil biodisinfection technique is a viable and compatible method with other techniques for integrated crop management, as well as for biological control and plant growth stimulation in primary production.
    No preview · Chapter · Dec 2011
  • [Show abstract] [Hide abstract]
    ABSTRACT: The quantitative study of heat treatments for sterilisation uses the Bigelow model to calculate the sterilising value (F). Calculation of F requires the previous determination of parameters D (decimal reduction time at experimental temperature) and Z (thermal-death time parameter), obtained from the thermal-death kinetics. Herein we compare two different methods, namely the Bigelow model and a predictive-type statistical method, to calculate the sterilisation effect against Bacillus coagulans spores when heat was applied to runner bean preserves (variety: Helda). Samples were subjected to various autoclave treatments at working temperatures (T ai) of 105, 107, 110, and 115°C for periods from 3 to 35 min. The microorganism used was B. coagulans. Sterilisation achieved by these autoclave treatments was determined by using the equation based on the Bigelow model (n probe = F zTi/D Ti) where n is the fractional concentration of colony-forming units (or some quality factor), F zTi is F at temperature T i, and D Ti is D at temperature T i. The Bigelow model can be used to obtain Z (thermal-death time parameter), which is needed to calculate the traditional sterilisation factor F, but not to determine the reduction factor n for the heat treatments, particularly when microbial indicators with low decimal reduction times (D) are studied. The thermokinetic parameters for B. coagulans in runner bean solution resulted to be Z = 10.64°C and D 121 = 0.0264 min (Af = 1.04). Treatment at 115°C for 20 min resulted in the most efficient sterilisation effect for B. coagulans.
    No preview · Article · Aug 2011 · Food Analytical Methods
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: To evaluate the daily dietary intake of essential metals in the Canary Islands, the iron, copper, zinc and manganese contents in 420 food and drink samples collected in local markets were analysed by inductively coupled plasma-atomic emission spectrometry (ICP-AES). The estimated daily dietary intakes of iron, copper, zinc and manganese are 13.161 mg/day, 2.098 mg/day, 8.954 mg/day and 2.372 mg/day, respectively. The iron dietary intake was found to be below the recommendations fixed for adult women, while the copper and manganese dietary intakes fulfilled the Recommended Dietary Allowances. The mean daily intake of zinc was below the Recommended Dietary Allowance. Cereals were found to be the food group that contributed most to the intake of these metals. While the island of El-Hierro presented iron, copper, zinc and manganese mean intakes over the estimated intakes for the whole archipelago, Fuerteventura island showed the lowest intakes. Tenerife and Fuerteventura showed the lowest iron intakes, being below the recommendations.
    Full-text · Article · Nov 2009 · International Journal of Food Sciences and Nutrition
  • [Show abstract] [Hide abstract]
    ABSTRACT: The concentrations of three toxic heavy metals, mercury (Hg), lead (Pb), and cadmium (Cd), were determined in preserved variegated scallops (Chlamys varia, Bivalvia, Mollusca), which are often consumed in Tenerife (Canary Islands, Spain). A total of 300 samples of seven commercial brands (A, B, D, H, J, L, and M) and one processed product ("scallop sauce") were analyzed. Samples were collected weekly in a major shopping area in Santa Cruz de Tenerife during a 12-month period. The concentrations of lead and mercury were far below the maximum limit permitted for human consumption by the European Communities Commission regulation (EC) 466/2001 (1 and 0.5 mg kg(-1) wet weight for Pb and Hg, respectively). Concentrations of cadmium were close to the maximum limit permitted by regulation (EC) 466/2001 (1 mg kg(-1) wet weight).
    No preview · Article · Jan 2008 · Journal of food protection
  • [Show abstract] [Hide abstract]
    ABSTRACT: Concentrations of mercury were determined for tinned molluscs (Mollusca, Bivalvia), i.e., mussels (Mytilus spp.), cockles (Cerastoderma edule), variegated scallops (Chlamys varia), and razor shells (Ensis spp.), consumed in Spain. A total of 220 samples were analyzed: 120 mussels, 40 cockles, 24 variegated scallops, and 36 razor shells. Samples were obtained weekly from markets in Santa Cruz de Tenerife (Canary Islands) over a period of 12 months. All observed concentrations of mercury were below the maximum permitted for human consumption (0.5 mg/kg) as defined by European Community Decision 93/ 351/CE. Mercury concentrations were 27.28 +/- 12.43 microg/kg for mussels, 66.59 +/- 23.53 microg/kg for cockles, 33.68 +/- 15.76 microg/kg for variegated scallops, and 21.26 +/- 12.24 microg/kg for razor shells. To evaluate the importance of mercury as a food contaminant, the percentage ingested daily, the weight of mercury in the diet, and the calculated percentage of this metal in the diet contributed by reference species were estimated.
    No preview · Article · Oct 2006 · Journal of food protection
  • [Show abstract] [Hide abstract]
    ABSTRACT: For most people diet is the main route of exposure to trace metals, so information about dietary intake is also important to assess risks to human health for these elements. The purpose of this study was to determine the levels of Pb in the foods and drinks of highest consumption in the authors' our community to estimate daily intakes of Pb for each of the seven Canary Islands. Four hundred and twenty samples were analyzed using GFAAS. The total Pb intake of the Canarian population is 72.8 microg/day, 29.12% (for a person of 70 kg body weight) of the provisional tolerable weekly intake limit of 25 microg/kg fixed by the FAO/WHO. The island that presents the highest lead intake is La Gomera, followed by Lanzarote, Tenerife, and Gran Canaria islands. These four islands present a lead dietary intake over the mean Pb intake for the whole archipelago. The islands with lower Pb intakes are La Palma and Fuerteventura, with intakes under 70 microg/day. These results have also been compared with the values found for other national and international communities.
    No preview · Article · Sep 2005 · Journal of Agricultural and Food Chemistry
  • C. Revert · A. Hardisson · J.I. Reguera · C. Rubio · J. Pagés
    [Show abstract] [Hide abstract]
    ABSTRACT: Legionellosis is a disease with an environmental origin frequently associated with pneumonia and produced by the bacterium Legionella pneumophila. It can be presented either in buds or in isolated cases. It seems to be a disease that is reemerging, but it has to be taken into account that this disease could have been unnoticed before the improvement in the present diagnostic methods. Given the Legionellosis buds that have recently occurred in Spain and their increasing incidence on the pneumonias acquired in the community, their high lethality on older people or people with a subjacent disease, the economic importance in tourist cities and the possibility of prevention by means of controlling the related facilities, we have considered of interest its divulgence.
    No preview · Article · Sep 2002 · Atencion Farmaceutica
  • [Show abstract] [Hide abstract]
    ABSTRACT: The contents of total sulphite in frozen prawns and shrimps were determined by the Monier–Williams procedure. The use of sulphites could be breaching legislative limits since the residues in the edible parts of some frozen prawns and shrimps samples were found to be higher than 150 mg SO2 per kg (maximum concentration admitted in the edible parts for these fresh and frozen products according to the current legislation). The non-edible parts presented much higher concentrations.
    No preview · Article · Jun 2002 · Food Control
  • A. Hardisson · A.González Padrón · J.I. Reguera
    [Show abstract] [Hide abstract]
    ABSTRACT: Nitrates and nitrites in 27 types of food products for infants from three commercial brands, of normal consumption in the Canary Islands, were determined. The assay of nitrates and nitrites in the solution obtained from the extraction process was undertaken according to the rules of AFNOR. Nitrites were evaluated by means of the Griess response and nitrates were evaluated in the same way after reduction by means of a cadmium column. The highest nitrate levels were observed in foodstuffs, whose principal ingredient was carrot; these levels exceded the maximum level (250 ppm) recommended by the ESPGAN regulation. In general the highest contents of nitrates were found in foodstuffs for infants which contained vegetables. The average values found in Nutriben and Nestle brands, especially in food products containing vegetables as the main ingredient, were higher than the maximum allowed levels of the French regulation.
    No preview · Article · Mar 1996 · Journal of Food Composition and Analysis