The aim of the study was to investigate the possible use of nine Lactobacillus strains, previously isolated from infants faeces, as components of industrial starter cultures for yoghurt, soft white cheese and hard cheese production. There were no strong antagonistic interactions between isolates and commercial probiotics and yoghurt strains. None of isolates was able to grow at 3℃, seven grew at 7℃, all of them at 12℃ and 37℃ and only three at 45℃. In the culture media containing 10.4% NaCl at pH 6.5 growth of four isolates was detected at 12℃, whereas six strains grew at 37℃. Tested isolates did not hydrolyze casein and arginine and did not produce H₂S. Inulins (HD, IQ, TEX, HPX) and maltodextrins (low and medium dextrose equivalent) added to the culture media stimulated the growth of isolates. The properties of all isolates enable their application in soft white and hard cheeses and strains 4a, 4b and 14 in yoghurts.
Twenty strains of Lactobacillus sp., previously isolated from infants’ faeces (MODZELEWSKA et al. 2003) were evaluated for their probiotic properties such as resistance to rifampicin, neomycin, kanamycin, chloramphenicol, ampicillin, penicillin, nalidixic acid, gentamycin, colistin, oxaciclin and nitrofurantoin, survivability in the environment similar to the present in the gastrointestinal tract – pH 2 and 3 and bile salts concentration 1.2, 2.5 and 5%. All strains were resistant to colistin and nalidixic acid and susceptible to rifampicin, nitrofurantoin, chloramphenicol and ampicillin. Strains showed high survivability in pH 2 and 3. After 6 h incubation bacterial counts were at the level of 8.3-7.2 log cfu cm⁻³ compared to initial 8.7-7.2 log cfu cm⁻³. In the environment containing 1.2-5% of bile salts bacterial counts after incubation were from below 1 to 6.6 log cfu cm⁻³. Nine strains, which survived in the highest numbers in bile salts solutions, were considered as capable of surviving passage through the gastrointestinal tract, which is one of the basic requirements which probiotic strains must fulfil.
Salmonella sp. jest jedną z głównych przyczyn zatruć pokarmowych. Z uwagi na czasochłonność standardowej metody wykrywania tego patogenu w żywności istnieje potrzeba doskonalenia metod alternatywnych. W badaniach zastosowano fluorescencyjną hybrydyzację in situ (FISH) z użyciem sondy Sal3 do wykrywania obecności Salmonella sp. w mięsie drobiowym (zaszczepionym Salmonella sp. oraz innymi pałeczkami z rodziny Enterobacteriaceae) i porównano ją z immunodiagnostyczną metodą enzymoimmunofluorescencyjną (VIDAS® SLMX) oraz metodą wg PN-ISO-6579. Metodami: FISH i VIDAS nie otrzymano wyników fałszywie negatywnych. Metodą VIDAS uzyskano jednak kilka wyników fałszywie pozytywnych. W metodzie FISH nie zaobserwowano hybrydyzacji ze szczepami innymi niż Salmonella sp. Wyniki wskazują na możliwość zastosowania FISH jako szybkiej metody wykrywania Salmonella sp. w mięsie drobiowym.
W artykule przedstawiono niektóre poglądy na dietetyczno-lecznicze właściwości bakterii fermentacji mlekowej oraz ich wpływ na zdrowie człowieka. Wskazano także na ich rolę w kształtowaniu odpowiedniej strawności, wartości odżywczej i przyswajalności mlecznych produktów fermentowanych. Zaprezentowano również znaczenie bakterii fermentacji mlekowej w ekologii mikroflory przewodu pokarmowego, ich właściwości przeciwinfekcyjne, przeciwmiażdżycowe i antykancerogenne, z uwzględnieniem zagrożeń wynikających z nadmiernego spożycia kwasu mlekowego o konfiguracji D (-).
The influence of inulin HPX and potentially probiotic Lactobacillus plantarum 14 strain on microbial quality and organoleptic properties of soft cheese were studied. Also the effect of inulin on probiotic concentration was examined during 45 days of storage at 6°C. Four versions of soft cheese were produced: (1) control without synbiotic, (2) with L. plantarum 14, (3) with inulin HPX 2.5 g/100 g of cheese, (4) with inulin HPX 2.5 g/100 g of cheese and L. plantarum 14. The number of potentially probiotic bacteria was affected by the addition of inulin HPX (p<0.05). In all probiotic cheeses the concentration of potentially probiotic strain was at a recommended level of 106–107 cfu/g. Also sensory quality was positively affected by the presence of inulin in products. After production and 45 days of storage the most desirable properties possessed cheese produced with the addition of inulin HPX, followed by control cheese. Microbial quality of all cheeses was satisfactory.
The aim of study was to evaluate the use of different levels of NSP degrading blend of enzymes (β-xylanase and β-glucanase) in practical wheat/barley-based diets for growing turkeys. The growth performance, as well as intestinal metabolism indicators of BIG-6 female turkeys was measured during the 8 weeks of experimental feeding. Turkeys were fed diets without enzyme supplementation (control group) or diets supplemented with enzyme preparation applied at doses of 50 (low), 100 (medium) and 150 mg/kg diet (high). The feed enzyme preparation contained a blend of xylanase (210 000 U/g) and β-glucanase (130 000 U/g of product). In the growth trial, enzyme supplementation did not significantly affect the body weight of the turkeys. The highest dose (150 mg/kg) of enzyme preparation decreased (p≤0.05) ileal viscosity (2.42 vs. 2.66 mPa.s), caecal viscosity (9.12 vs. 11.36 mPa.s), and weight of small intestinal tissue (10.6 vs. 13.4 g/kg BW) and feed conversion ratio of trial turkeys (by 3.5%) in comparison with the control animals. Enzyme supplementation also caused a visible growth tendency in total VFA in the caecal digesta of the turkeys. The proportions of major fatty acids also changed compared with the control group and the production of acetic acid increased, whereas the production of propionic acid decreased. No enzyme addition response was observed for lactic acid bacteria, Enterobacteriaceae, Escherichia coli or Clostridium perfringens rods in caecal digesta of turkeys, but the aerobic spore forming bacteria count decreased (p≤0.05). The best performance and physiological response of turkeys was obtained after applying the highest proportion (150 mg/kg) of enzyme preparation to the diet.
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