Search results for "bacteri"

Distribution patterns of fungi and bacteria in saline soils

2014

Saline soils are environments characterized by uneven temporal and spatial water distribution and localized high concentrations of salts. Spatial distribution patterns of fungi and bacteria in saline soils, and the link between microbial community dynamics and salts accumulation are critical issues throughout the world (Ettema, Wardle 2002). This study was focused on spatial distribution patterns of soil fungi and bacteria in a saline soil located in Piana del Signore (Gela, Italy) where some ecological variables acted as shaping factors in aboveground and belowground communities distribution. Bacterial, archaeal, and fungal communities diversity and distribution in ten soil sites (A horizo…

Development of new dairy products using raw ewe’s milk to produce a “Swiss” type cheese

2022

Preliminary Evaluation of the Influence of Traditional Dairy Plant Equipment on the Microbiological Quality of “Caciocavallo Palermitano” Cheese

2010

Caciocavallo Palermitano” is a raw cows’ milk cheese produced within Palermo province (Sicily), processed according to “pasta-filata” cheese technology without starter addition. Production flow-sheet includes a 15-minute milk bulk resting in “tina”, the traditional wooden vat used for cheese-making. This study was aimed to evaluate the influence of traditional equipment on the characteristics of cheese; at this stage, it was forwarded to the characterization of the microbiological populations of “Caciocavallo Palermitano” during each step of manufacturing. Two milk bulks (A and B), from different farming systems, were compared before and after resting in tina. After delivery at dairy factor…

Transfer, composition and technological characterization of the lactic acid bacterial populations of the wooden vats used to produce traditional stre…

2015

The biofilms of 12 wooden vats used for the production of the traditional stretched cheeses Caciocavallo Palermitano and PDO Vastedda della valle del Belìce were investigated. Salmonella spp. and Listeria monocytogenes were never detected. Total coliforms were at low numbers with Escherichia coli found only in three vats. Coagulase-positive staphylococci (CPS) were below the enumeration limit, whereas lactic acid bacteria (LAB) dominated the surfaces of all vats. In general, the dominance was showed by coccus LAB. Enterococci were estimated at high numbers, but usually between 1 and 2 Log cycles lower than other LAB. LAB populations were investigated at species and strain level and for thei…

Persistence of wild Streptococcus thermophilus strains on wooden vat and during the manufacture of a traditional Caciocavallo type cheese

2012

The present work was undertaken to evaluate the influence of the wooden dairy plant equipment on the microbiological characteristics of curd to be transformed into Caciocavallo Palermitano cheese. Traditional raw milk productions were performed concomitantly with standard cheese making trials carried out in stainless steel vat inoculated with a commercial starter. Milk from two different farms (A and B) was separately processed. The wooden vat was found to be a reservoir of lactic acid bacteria (LAB), while unwanted (spoilage and/or pathogenic) microorganisms were not hosted or were present at very low levels. All microbial groups were numerically different in bulk milks, showing higher lev…

Evolution of indigenous starter microorganisms and physicochemical parameters in spontaneously fermented beef, horse, wild boar and pork salamis prod…

2020

Abstract The present work was carried out to evaluate the microbiological and physicochemical composition of salamis produced with the meat of beef, horse, wild boar and pork. Salami productions occurred under controlled laboratory conditions to exclude butchery environmental contaminations, without the addition of nitrate and nitrite. All trials were monitored during the ripening (13 °C and 90% relative humidity) extended until 45 d. The evolution of physicochemical parameters showed that beef and pork salamis were characterized by a higher content of branched chain fatty acids (FA) and rumenic acid than horse and wild boar salamis, whereas the last two productions showed higher values of …

Molecular characterization of dominant bacterial population in “Vastedda della Valle del Belice” cheese: preliminary investigation

2010

The sensory characteristics of raw-milk cheeses are linked to the cheese-making process, to the environmental factors as animal feeding and to the biochemical and microbiological composition of the milk. In this report we temped to characterize the microflora in the typical Sicilian historical cheese as Vastedda della valle del Belice. Each cheese was previous subjected to microbial isolation on specific media (M17 and MRS). The colony obtained on the solid medium were subject to biochemical tests and DNA extraction. The microbial diversity occurring in the strains was evaluated by PCR, RFLP and sequencing targeted on 16S ribosomal DNA. A number of closest relatives species of lactic and co…

BATTERI LATTICI CON ATTIVITA’ ANTIBATTERICA ISOLATI DA FORMAGGI TRADIZIONALI SICILIANI

2013

The study was conducted on typical Sicilian cheeses made from raw cow milk (Caciocavallo Palermitano) and sheep milk (Vastedda della valle del Belice PDO e Pecorino PDO). Genotypic identification of the LAB isolates was carried out by 16S/23S rRNA sequencing. a total of 400 bacteria strains were isolated and genotypically identified as Lactobacillus spp., Lactoccoccus spp., Pediococcus spp., Leuconostoc spp., Enterococcus spp. and Streptococcus spp. Evaluation of bacteriocin-producing LAB was investigated in vitro using the “spot on the lawn” method (2) aganist Listeria monocytogenes, Staphylococcus aureus, Salmonella enteritidis and Escherichia coli. Results showed a predominance of LAB sh…

EVALUATION OF BACTERIAL AND FUNGAL LOAD IN FRESH, FROZEN AND DRIED FOOD MUSHROOMS

2015

The analysis carried out by Doores et al. (1) and Venturini et al. (2) on the total bacterial load tested in wild and cultivated fresh mushrooms highlight values ranging between 3.7 and 9.3 log ufc/g. Due to the absence of pathogens, the microbiological quality of mushrooms analysed by the above-mentioned authors has been considered good. On the basis of data reported in literature we have also extended the observations with frozen and dried mushrooms in order to evaluate the mesophilous bacterial and fungal load. In particular the presence/absence of Escherichia coli (Migula,1895) Castellani & Chalmers, 1919, Salmonella spp. and Listeria monocytogenes (Murray et al.1926) Pirie 1940 was…

Bioactive compounds from brown algae inhabiting the north-western Mediterranean Sea

2021

Marine algae produce a great amount of secondary metabolites (e.g. terpenoids, fatty acids, steroids, polysaccharides and polyphenols) to face environmental stressors they are exposed to, but also to defend themselves from biological pressures such as competitors, pathogens, grazers and epiphytes. Over the last decade, secondary metabolites isolated from brown algae and phenolic compounds, in particular, are receiving increasing attention due to their putative ecological roles, and several biological properties. Brown fucoid algae of the genus Cystoseira sensu latu (Sargassaceae) and Dictyotaceae produce a wide variety of secondary metabolites which have been investigated mainly for their d…