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We studied the growth and capacities for pesticides removal of bacterial strains isolated from the Laguna Grande, an oligotrophic lake at the South of Spain (Archidona, Málaga). Strains were isolated from water samples amended with 10 and 50 microg/ml of nine pesticides: organochlorinated insecticides (aldrin and lindane), organophosphorous insecticides (dimetoate, methyl-parathion and methidation), s-triazine herbicides (simazine and atrazine), fungicide (captan) and diflubenzuron (1-(-4-chlorophenyl)-3-(2,6-difluorobenzoyl urea), a chitinase inhibitor. The majority of the strains belonged to the genera Pseudomonas and Aeromonas and only 9% of the total of strains were Gram positive. From all the strains isolated, only 22 showed a wide growth range in all the pesticides tested and 4 of them were chosen for pesticide removal studies. The genetic identification of these strains showed their affiliation to Pseudomonas pseudoalcaligenes, Micrococcus luteus, Bacillus sp. and Exiguobacterium aurantiacum. These last two strains were those that showed the highest pesticide removal capacities and a high bacterial growth.

This article describes a microbiological study carried out on lacón, a dry-cured meat product made in the north-west of Spain from the fore extremity of pig. Using classical methods, aerobic mesophilic flora, salt-tolerant flora, lactic acid bacteria, Enterobacteriaceae, enterococci, moulds and yeasts were enumerated, some physicochemical parameters (pH, aw and moisture and NaCl contents) were determined and a representative number of isolates of the salt-tolerant flora (the main microbial group) were identified during the manufacture of five batches. All the microbial groups, with the exception of Enterobacteriaceae and enterococci, reached maximum counts both on the surface and in the interior of the pieces at the end of the post-salting stage and afterwards progressively dropped during the drying-ripening stage. Staphylococcus xylosus, Staph. saprophyticus, Staph. simulans, Staph. sciuri and Micrococcus luteus were the main species isolated throughout manufacturing. This study will significantly increase knowledge of the microbiology of cured meat products made from entire pieces.

The Iberian dry cured ham is an uncooked meat product highly appreciated because of its characteristic flavour. This product is obtained from highly marbled Iberian pig hindlegs after 18-24 months of maturation under natural environmental conditions. The role of Micrococcaceae in the development of the aroma characteristics of this products remains unclear. Identification of Gram-positive, catalase-positive cocci isolated from Mannitol Salt Agar plates showed that Staphylococcus xylosus followed by Staphylococcus equorum are the predominant organisms, even after 16 months of maturing. A remarkable variety of types of both staphylococci and micrococci are detected at any sampling time. The metabolic activities of these organisms could contribute to the characteristics of the final product.

Samples (120) of ewes' raw milk collected over a 12-month period on arrival at the dairy and freshly drawn ewes' milk samples (30) collected at the farm were analysed for total viable counts and staphylococci. Total viable counts reached on the average 5.4 X 10(6)/ml in dairy samples and 6.0 X 10(5)/ml in farm samples, whereas mean levels of staphylococci were 5.9 X 10(4)/ml and 3.3 X 10(3)/ml, respectively. A high proportion (62%) of coagulase-positive isolates from Baird-Parker agar plates was detected in spring months. Staphylococcus aureus (42%), Staph. haemolyticus (23%) and Staph. epidermidis (10%) were the predominant species in 210 characterized isolates of staphylococci from ewes' raw milk. Seven coagulase-positive, maltose-negative staphylococci could not be identified with any of the recognized Staphylococcus species. Eighteen Micrococcus strains were identified as M. varians, whereas 111 Micrococcus strains of uncertain taxonomic status were separated into three groups, according to their physiological characters.