Andreja Canzek Majhenic - Academia.edu (original) (raw)
Papers by Andreja Canzek Majhenic
Mljekarstvo, 2011
Saetak Cilj ovog rada bio je analizirati strukturu mikrobnih konzorcija tradicionalnog svjeeg o... more Saetak Cilj ovog rada bio je analizirati strukturu mikrobnih konzorcija tradicionalnog svjeeg ovčjeg sira Karakačanski skakutanac. Jedanaest sireva sakupljeno je tijekom sezone proizvodnje od travnja do rujna. Mikrobni konzorciji sakupljeni su sa 3 hranjive ...
Food Technology and Biotechnology, Sep 14, 2012
The objective of this study is to describe the diversity of indigenous cultivable community of th... more The objective of this study is to describe the diversity of indigenous cultivable community of the lactobacilli associated with the production of traditional Istrian cheese and to get a collection of well characterized strains. Raw milk and cheese samples were collected from three different farms in Istria during ripening. A total of 212 mesophilic and thermophilic Lactobacillus isolates as well as bulk colonies (consortia) were investigated using culture-dependent approach combining phenotyping and genotyping. Biochemical fingerprinting with PhenePlate-LB system preliminary grouped 212 isolates in 16 distinct PhP types. Only one representative isolate from each PhP cluster was further analyzed by genotyping for a reliable identification at the genus and species level by employing PCR techniques and sequencing of 16S rRNA genes. Sequence analysis of 16S rRNA revealed the presence of Lactobacillus plantarum, Lactobacillus brevis, Lactobacillus casei, Lactobacillus paracasei and Lactobacillus rhamnosus. Lactobacilli were screened for possible resistance against seven selected antibiotics: ampicillin, tetracycline, penicillin, rifampin, clindamycin, erythromycin and vancomycin. Although there was no clear pattern of antimicrobial susceptibility to most tested antibiotics, all representative isolates were resistant to vancomycin. The analysis of bulk colonies by denaturing gradient gel electrophoresis (DGGE) identified Lactobacillus plantarum and Lactobacillus brevis as predominant members of Lactobacillus population. Pediococcus pentosaceus, Pediococcus acidilactici, Streptococcus sp. and Leuconostoc mesenteroides were also detected as part of the analysed consortia. The prevalence of identified species and community members of lactobacilli agrees with other studies of raw milk cheese and represents a useful base for further selection.
Food Science and Technology International, Aug 1, 2022
Enterococci represent a significant part of the non-starter LAB microbiota of artisanal cheeses p... more Enterococci represent a significant part of the non-starter LAB microbiota of artisanal cheeses produced mainly from raw milk. Common approaches to safety evaluation of enterococci isolates include assessment of antimicrobial resistance and virulence potential. Hence, a collection of 47 (n = 22, Serbia; n = 25, Slovenia) dairy enterococcal isolates, of which E. faecalis (n = 28), E. faecium (n = 11), E. durans (n = 5), E. casseliflavus (n = 2), and E. gallinarum (n = 1), was analyzed. The susceptibility to 12 antimicrobials was tested using a broth microdilution method, and the presence of the selected antimicrobial resistance and virulence genes was investigated using PCR. Isolates were resistant to tetracycline (TET) (25.5%), erythromycin (ERY) (17.0%), gentamycin and chloramphenicol (CHL) (∼6%). No resistance to ampicillin (AMP), ciprofloxacin (CIP), daptomycin (DAP), linezolid (LZD), teicoplanin (TEI), tigecycline (TGC) and vancomycin (VAN) was detected. Among all the resistance determinants analyzed, ermB gene was detected most frequently. All 10 virulence genes analyzed were detected with a distribution of cpd (72.3%), cob and ccf (70.2%), gelE (68.1%), hyl (59.6%), agg (53.2%) and esp (46.8%). The genes encoding cytolysin ( cylA, cylM and cylB) were amplified to a lesser extent (21.3%, 21.3% and 12.8%, respectively). However, due to the limited number of enterococci isolates analyzed in the present study, further studies are still required in order to better document the safety status of dairy enterococci.
Lactic acid bacteria (LAB) are common inhabitants of the gastrointestinal (GI) tract and have imp... more Lactic acid bacteria (LAB) are common inhabitants of the gastrointestinal (GI) tract and have important role in maintaining the equilibrium of GI flora, which can be influenced by various factors like diets, antimicrobials and stress. Minimal inhibitory concentrations (MIC) and minimal bactericidal concentrations (MBC) of 6 antibiotics, commonly used in human medicine for 8 selected lactobacilli strains were determined by macrodilution and microdilution methods in liquid media and by diffusion method on agar plates. The effects of Penicillin G and Ampicillin on intestinal LAB were tested in vivo on mice as well. Lactobacilli were sensitive to Penicillin G, (penicillines and their derivatives) and Erythromycin (macrolides) by in vitro testing. Clyndamycin (pyranosid) showed moderate inhibitory effect. All lactobacilli strains were resistant to Kanamycin and Neomycin (aminoglycosides), while L. salivarius IM 124 has shown extra resistance to Erythromycin and Clyndamycin. The influence of orally administered Ampicillin showed no significant influence on LAB count in mice faeces. The effect of Penicillin G on mice LAB total count was significant, while no effect of orally administered lactobacilli was determined.
John Wiley & Sons, Ltd eBooks, Nov 10, 2017
Mljekarstvo, Jun 18, 2020
Goat's daily diet is usually based on grazing, hay and/or feed supplements. Feed supplements are ... more Goat's daily diet is usually based on grazing, hay and/or feed supplements. Feed supplements are crucial in the diet of high productive goats to achieve their genetic potential and breeders must choose balanced feeding regime to produce large quantities of milk without affecting the technological quality of milk. In the present study, we evaluated the influence of two commercially available feed supplements on goat milk coagulation properties and rheological properties of yoghurts. Goats of the Slovenian Alpine breed (61) were fed with two feed supplements during the 3-year experiment. Feed supplement 1 (FS1) had higher proportions of barley and alfalfa, while feed supplement 2 (FS2) had added premix of minerals and vitamins and had higher proportions of wheat and sunflower meal. Consequently, FS1 had more crude fibres, which is the most probable reason for approximately 15 % higher firmness, consistency and cohesiveness (P<0.05) of yoghurts in FS1 group, compared to the FS2 group. Moreover, the rennet coagulation time (r) was shorter (P<0.05) in the FS1 group, compared to the FS2 group. Curd firmness 30 min after enzyme addition (a 30) was also higher in FS1 group although the results were not statistically significant. Taking together, our results indicate that goats fed with FS1 produced milk with better technological properties compared to those fed with FS2, despite the fact that there were no significant differences in chemical composition of milk from each group. We showed that careful selection of feed supplement's constituents could improve technological properties of goat milk. However, further studies are needed to evaluate the mechanisms of the observed differences.
CRC Press eBooks, Feb 17, 2017
International Journal of Dairy Technology, Oct 23, 2017
The microbial stability of kefir grains and kefir beverage during 10-week propagation in two diff... more The microbial stability of kefir grains and kefir beverage during 10-week propagation in two different laboratories was investigated. Plate counts and denaturing gel gradient electrophoresis (DGGE) fingerprints of lactobacilli and yeasts from kefir grains were comparable between the two laboratories, with Lactobacillus kefiranofaciens subsp. kefirgranum, Lb. kefiri, Lb. parakefiri, Kluyveromyces marxianus and Kazachstania exigua being the prevalent microorganisms. The counts and composition of lactobacilli and yeasts in the kefir beverage in all serial sampling in both laboratories were also very stable and similar to those obtained with kefir grains. Our findings demonstrate that a stable microbiota of kefir grains ensures consistent and constant product quality that is of crucial importance for dairy industry.
OMICS: A Journal of Integrative Biology
In this perspective analysis, we strive to answer the following question: how can we advance inte... more In this perspective analysis, we strive to answer the following question: how can we advance integrative biology research in the 21st century with lessons from animal science? At the University of Ljubljana, Biotechnical Faculty, Department of Animal Science, we share here our three lessons learned in the two decades from 2002 to 2022 that we believe could inform integrative biology, systems science, and animal science scholarship in other countries and geographies. Cultivating multiomics knowledge through a conceptual lens of integrative biology is crucial for life sciences research that can stand the test of diverse biological, clinical, and ecological contexts. Moreover, in an era of the current COVID-19 pandemic, animal nutrition and animal science, and the study of their interactions with human health (and vice versa) through integrative biology approaches hold enormous prospects and significance for systems medicine and ecosystem health.
Probiotics for Human Nutrition in Health and Disease
Sveučilišna tiskara, Zagreb, 2012
Beneficial Microbes in Fermented and Functional Foods, 2014
Atlas ovcjih sireva zemalja zapadnog Balkana predstavlja rezultat međunarodnog SEE-ERA.NET Plus J... more Atlas ovcjih sireva zemalja zapadnog Balkana predstavlja rezultat međunarodnog SEE-ERA.NET Plus Joint Call projekta naslova: Characterisation and tracking the origin of specific features of traditional cheeses in Western Balkans". Projekt je imao za cilj okupiti istraživacke timove iz Hrvatske, Slovenije, Bosne i Hercegovine i Srbije, u nastojanju definiranja znanstveno-istraživackog sustava za karakterizaciju tradicionalnih sireva zemalja zapadnog Balkana (Istarski, Krcki, Paski ; Bovski, Dolenjski, Kraski ; Livanjski, Travnicki/Vlasicki ; Pirotski, Sjenicki sir). Sustav je ukljucivao standardizaciju tehnoloskog postupka proizvodnje tradicionalnih ovcjih sireva kao i definiranje njihovih fizikalno-kemijskih i senzornih svojstava te dominantnih bakterijskih populacija ukljucenih u proces zrenja karakteristican za svaki pojedini sir.
Journal of Food Science and Technology, 2014
The article title has been published with misspelled entry. The word "sesonal" should be "seasona... more The article title has been published with misspelled entry. The word "sesonal" should be "seasonal". The correct title should be "Volatile compounds in Nanos cheese: their formation during ripening and seasonal variation", as shown above.
Journal of Food Science and Technology, 2014
ABSTRACT The objective of this study was to evaluate the formation of volatile compounds (VCs) du... more ABSTRACT The objective of this study was to evaluate the formation of volatile compounds (VCs) during ripening time in different seasons (summer, winter) of Nanos cheese with Protected Designation of Origin (PDO). The study was also undertaken to compare the aroma profile of feed and milk sampled in two different seasons from the protected area. The VCs analysis was performed by solid-phase micro extraction-gas chromatography–mass spectrometry. Altogether, 62 dif-ferent VCs were detected throughout cheese ripening where their quantity varied with the time of ripening and season. In cheeses from winter season, there was a higher concentration of some fatty acids and esters. Besides, the evaluated differ-ences of cheese samples by season indicated the transfers of some VCs from feed and/or milk into cheese. The most important possible links between cheese with feed and/or milk from different season were found in case of 9 VCs (acetic acid, butanoic acid, 3-methyl butanoic acid, hexanoic acid; ethyl ester of hexanoic acid, -octanoic acid, and -decanoic acid-; 2-butanone, pinane, sabinene) which also define the season. The changes in the amount of some VCs through ripening were significant (e.g. content of some fatty acids and esters increased while content of acetoin and diacetyl decreased). This is the first report which deals with the changes in cheese during ripening influenced by season and feeding system and the transfers of VCs from feed and milk to cheese in the case of traditional Nanos cheese, which was chosen as a model system for other hard type cheeses.
Acta Alimentaria, 2018
This study was undertaken to prepare tailor-made starter culture (TMSC) for Karst ewe's cheese pr... more This study was undertaken to prepare tailor-made starter culture (TMSC) for Karst ewe's cheese production. Therefore, basic technological characteristics (growth ability in milk, acid production, and proteolytic activity) and antistaphylococcal potential were assessed for autochthonous enterococci and lactobacilli. Beside good growth in milk with numbers as high as 8 log CFU ml-1 , certain enterococci and lactobacilli also reduced pH below 5.0 and showed proteolytic activity. In antistaphylococcal testing, only pure strains of enterococci and lactobacilli were moderately antagonistic, but not in coagulated milks and coagulated milk extracts. Enterococci and lactobacilli with most relevant technological/antistaphylococcal properties were combined and tested as TMSC. In control (C) cheese-making, milk was inoculated with TMSC, while staphylococci (SC) cheese-making included contamination with staphylococci. In C trials, high logarithmic counts per g of cheese for enterococci (8.07-8.80) and lactobacilli (7.49-9.98) throughout the ripening period were found, and their authenticity was monitored by RAPD method. Furthermore, cheese extracts failed to inhibit pure cultures of staphylococci, while cheese pieces inhibited Staphylococcus sp. ST17. In SC trials, population dynamics of enterococci (7.81-9.04) and lactobacilli (7.98-9.63) corroborated the results in milk and in C trials, with staphylococci still present at the end of the ripening period but at lower counts than in fresh cheese.
Applied Microbiology and Biotechnology, Sep 18, 2003
Lactobacillus gasseri LF221, an isolate from the feces of a child, produces two bacteriocins. Sta... more Lactobacillus gasseri LF221, an isolate from the feces of a child, produces two bacteriocins. Standard procedures for molecular techniques were used to locate, clone and sequence the fragments of LF221 chromosomal DNA carrying the acidocin LF221 A and B structural genes, respectively. Sequencing analysis revealed the gene of acidocin LF221 A to be an open reading frame encoding a protein composed of 69 amino acids, including a 16-amino-acid N-terminal extension. The acidocin LF221 B gene was found to encode a 65-amino-acid bacteriocin precursor with a 17-amino-acid N-terminal leader peptide. DNA homology searches showed similarities of acidocin LF221 A to brochocin B, lactococcin N and thermophilin B, whereas acidocin LF221 B exhibited some homology to lactacin F and was virtually identical to gassericin X. The peptides encoded by orfA1 and orfB3 showed characteristics of class II bacteriocins and are suspected to be the complementary peptides of acidocin A and B, respectively. orfA3 and orfB5 are proposed to encode putative immunity proteins for the acidocins. Acidocin LF221 A and acidocin LF221 B are predicted to be members of the two-component class II bacteriocins, where acidocin LF221 A appears to be a novel bacteriocin. L. gasseri LF221 is being developed as a potential probiotic strain and a food/feed preservative. Detailed characterization of its acidocins is an important piece of background information useful in applying the strain into human or animal consumption. The genetic information on both acidocins also enables tracking of the LF221 strain in mixed populations and complex environments.
Journal of Food and Nutrition Research, 2018
Mljekarstvo : časopis za unaprjeđenje proizvodnje i prerade mlijeka, Mar 15, 2011
The presence of gene determinants for different bacteriocins has been already demonstrated in tra... more The presence of gene determinants for different bacteriocins has been already demonstrated in traditional Slovenian types of raw milk cheeses 'Tolminc' and 'Kraški'. These genes were present also in the cultivable microbiota. In this research the aim was to establish how the presence of gene determinants for bacteriocins in microbial consortia is reflected in its antimicrobial activity. In addition, one of the goals was to determine whether the strains that carry gene determinants for bacteriocins have any competitive growth advantage in microbial population. Microbial consortium of 'Tolminc' cheese was propagated in milk and examined at the end of propagation its antimicrobial activity and the presence of gene determinants for bacteriocins. Comparison of the results obtained before and after propagation leaded to the conclusion that most of the strains possessing gene determinants for bacteriocins were unable to persist during propagation. The strains which did persist during propagation carried gene determinants for enterocins P, L50B and cytolysin. Antimicrobial activity of consortium before and after propagation was not substantially different and cannot be attributed to any of detected bacteriocins.
DOAJ (DOAJ: Directory of Open Access Journals), Sep 1, 2010
In-situ inhibition of Staphylococcus aureus by lactic acid bacteria consortia from two traditiona... more In-situ inhibition of Staphylococcus aureus by lactic acid bacteria consortia from two traditional Slovenian raw milk cheeses Original scientific paper-Izvorni znanstveni rad UDK: 637.354/579.861.2 Summary Bacteriocin(s) producing lactic acid bacteria naturally present in traditional cheeses represent an inexhaustive pool of microbes with safeguarding potential. Some bacteriocins produced by cheese lactic acid bacteria were already described as successful anti-staphylococcal agents. The presence of genes for bacteriocins with potential anti-staphylococcal activity was also demonstrated in two Slovenian traditional raw milk cheeses, "Tolminc" and "Kraški ovčji sir". Same bacteriocin genes were also detected in viable lactic acid bacteria consortia's isolated from "bacteriocin positive cheeses" on Rogosa, M17 and CATC agar media. The aim of the research was to elucidate whether or not this particular cheese consortia, in which bacteriocin genes were detected, actually exhibit anti-staphylococcal activity in milk and/or cheese. For this purpose different cheese consortia were selected in relation to versatility of detected bacteriocin genes and used to perform challenge tests against Staphylococcus aureus in milk and cheese. In milk following the time/temperature regime of traditional cheese production all cheese consortia effectively inhibited growth of Staphylococcus aureus in the range of app. 2 to 3 log. In cheese the inhibition of staphylococci was less pronounced but still evident since inhibition of app. 1.5 log was detected. Sole inhibition by lactic acid production was ruled out while linking inhibition directly to bacteriocin production would take some additional work.
Mljekarstvo, 2011
Saetak Cilj ovog rada bio je analizirati strukturu mikrobnih konzorcija tradicionalnog svjeeg o... more Saetak Cilj ovog rada bio je analizirati strukturu mikrobnih konzorcija tradicionalnog svjeeg ovčjeg sira Karakačanski skakutanac. Jedanaest sireva sakupljeno je tijekom sezone proizvodnje od travnja do rujna. Mikrobni konzorciji sakupljeni su sa 3 hranjive ...
Food Technology and Biotechnology, Sep 14, 2012
The objective of this study is to describe the diversity of indigenous cultivable community of th... more The objective of this study is to describe the diversity of indigenous cultivable community of the lactobacilli associated with the production of traditional Istrian cheese and to get a collection of well characterized strains. Raw milk and cheese samples were collected from three different farms in Istria during ripening. A total of 212 mesophilic and thermophilic Lactobacillus isolates as well as bulk colonies (consortia) were investigated using culture-dependent approach combining phenotyping and genotyping. Biochemical fingerprinting with PhenePlate-LB system preliminary grouped 212 isolates in 16 distinct PhP types. Only one representative isolate from each PhP cluster was further analyzed by genotyping for a reliable identification at the genus and species level by employing PCR techniques and sequencing of 16S rRNA genes. Sequence analysis of 16S rRNA revealed the presence of Lactobacillus plantarum, Lactobacillus brevis, Lactobacillus casei, Lactobacillus paracasei and Lactobacillus rhamnosus. Lactobacilli were screened for possible resistance against seven selected antibiotics: ampicillin, tetracycline, penicillin, rifampin, clindamycin, erythromycin and vancomycin. Although there was no clear pattern of antimicrobial susceptibility to most tested antibiotics, all representative isolates were resistant to vancomycin. The analysis of bulk colonies by denaturing gradient gel electrophoresis (DGGE) identified Lactobacillus plantarum and Lactobacillus brevis as predominant members of Lactobacillus population. Pediococcus pentosaceus, Pediococcus acidilactici, Streptococcus sp. and Leuconostoc mesenteroides were also detected as part of the analysed consortia. The prevalence of identified species and community members of lactobacilli agrees with other studies of raw milk cheese and represents a useful base for further selection.
Food Science and Technology International, Aug 1, 2022
Enterococci represent a significant part of the non-starter LAB microbiota of artisanal cheeses p... more Enterococci represent a significant part of the non-starter LAB microbiota of artisanal cheeses produced mainly from raw milk. Common approaches to safety evaluation of enterococci isolates include assessment of antimicrobial resistance and virulence potential. Hence, a collection of 47 (n = 22, Serbia; n = 25, Slovenia) dairy enterococcal isolates, of which E. faecalis (n = 28), E. faecium (n = 11), E. durans (n = 5), E. casseliflavus (n = 2), and E. gallinarum (n = 1), was analyzed. The susceptibility to 12 antimicrobials was tested using a broth microdilution method, and the presence of the selected antimicrobial resistance and virulence genes was investigated using PCR. Isolates were resistant to tetracycline (TET) (25.5%), erythromycin (ERY) (17.0%), gentamycin and chloramphenicol (CHL) (∼6%). No resistance to ampicillin (AMP), ciprofloxacin (CIP), daptomycin (DAP), linezolid (LZD), teicoplanin (TEI), tigecycline (TGC) and vancomycin (VAN) was detected. Among all the resistance determinants analyzed, ermB gene was detected most frequently. All 10 virulence genes analyzed were detected with a distribution of cpd (72.3%), cob and ccf (70.2%), gelE (68.1%), hyl (59.6%), agg (53.2%) and esp (46.8%). The genes encoding cytolysin ( cylA, cylM and cylB) were amplified to a lesser extent (21.3%, 21.3% and 12.8%, respectively). However, due to the limited number of enterococci isolates analyzed in the present study, further studies are still required in order to better document the safety status of dairy enterococci.
Lactic acid bacteria (LAB) are common inhabitants of the gastrointestinal (GI) tract and have imp... more Lactic acid bacteria (LAB) are common inhabitants of the gastrointestinal (GI) tract and have important role in maintaining the equilibrium of GI flora, which can be influenced by various factors like diets, antimicrobials and stress. Minimal inhibitory concentrations (MIC) and minimal bactericidal concentrations (MBC) of 6 antibiotics, commonly used in human medicine for 8 selected lactobacilli strains were determined by macrodilution and microdilution methods in liquid media and by diffusion method on agar plates. The effects of Penicillin G and Ampicillin on intestinal LAB were tested in vivo on mice as well. Lactobacilli were sensitive to Penicillin G, (penicillines and their derivatives) and Erythromycin (macrolides) by in vitro testing. Clyndamycin (pyranosid) showed moderate inhibitory effect. All lactobacilli strains were resistant to Kanamycin and Neomycin (aminoglycosides), while L. salivarius IM 124 has shown extra resistance to Erythromycin and Clyndamycin. The influence of orally administered Ampicillin showed no significant influence on LAB count in mice faeces. The effect of Penicillin G on mice LAB total count was significant, while no effect of orally administered lactobacilli was determined.
John Wiley & Sons, Ltd eBooks, Nov 10, 2017
Mljekarstvo, Jun 18, 2020
Goat's daily diet is usually based on grazing, hay and/or feed supplements. Feed supplements are ... more Goat's daily diet is usually based on grazing, hay and/or feed supplements. Feed supplements are crucial in the diet of high productive goats to achieve their genetic potential and breeders must choose balanced feeding regime to produce large quantities of milk without affecting the technological quality of milk. In the present study, we evaluated the influence of two commercially available feed supplements on goat milk coagulation properties and rheological properties of yoghurts. Goats of the Slovenian Alpine breed (61) were fed with two feed supplements during the 3-year experiment. Feed supplement 1 (FS1) had higher proportions of barley and alfalfa, while feed supplement 2 (FS2) had added premix of minerals and vitamins and had higher proportions of wheat and sunflower meal. Consequently, FS1 had more crude fibres, which is the most probable reason for approximately 15 % higher firmness, consistency and cohesiveness (P<0.05) of yoghurts in FS1 group, compared to the FS2 group. Moreover, the rennet coagulation time (r) was shorter (P<0.05) in the FS1 group, compared to the FS2 group. Curd firmness 30 min after enzyme addition (a 30) was also higher in FS1 group although the results were not statistically significant. Taking together, our results indicate that goats fed with FS1 produced milk with better technological properties compared to those fed with FS2, despite the fact that there were no significant differences in chemical composition of milk from each group. We showed that careful selection of feed supplement's constituents could improve technological properties of goat milk. However, further studies are needed to evaluate the mechanisms of the observed differences.
CRC Press eBooks, Feb 17, 2017
International Journal of Dairy Technology, Oct 23, 2017
The microbial stability of kefir grains and kefir beverage during 10-week propagation in two diff... more The microbial stability of kefir grains and kefir beverage during 10-week propagation in two different laboratories was investigated. Plate counts and denaturing gel gradient electrophoresis (DGGE) fingerprints of lactobacilli and yeasts from kefir grains were comparable between the two laboratories, with Lactobacillus kefiranofaciens subsp. kefirgranum, Lb. kefiri, Lb. parakefiri, Kluyveromyces marxianus and Kazachstania exigua being the prevalent microorganisms. The counts and composition of lactobacilli and yeasts in the kefir beverage in all serial sampling in both laboratories were also very stable and similar to those obtained with kefir grains. Our findings demonstrate that a stable microbiota of kefir grains ensures consistent and constant product quality that is of crucial importance for dairy industry.
OMICS: A Journal of Integrative Biology
In this perspective analysis, we strive to answer the following question: how can we advance inte... more In this perspective analysis, we strive to answer the following question: how can we advance integrative biology research in the 21st century with lessons from animal science? At the University of Ljubljana, Biotechnical Faculty, Department of Animal Science, we share here our three lessons learned in the two decades from 2002 to 2022 that we believe could inform integrative biology, systems science, and animal science scholarship in other countries and geographies. Cultivating multiomics knowledge through a conceptual lens of integrative biology is crucial for life sciences research that can stand the test of diverse biological, clinical, and ecological contexts. Moreover, in an era of the current COVID-19 pandemic, animal nutrition and animal science, and the study of their interactions with human health (and vice versa) through integrative biology approaches hold enormous prospects and significance for systems medicine and ecosystem health.
Probiotics for Human Nutrition in Health and Disease
Sveučilišna tiskara, Zagreb, 2012
Beneficial Microbes in Fermented and Functional Foods, 2014
Atlas ovcjih sireva zemalja zapadnog Balkana predstavlja rezultat međunarodnog SEE-ERA.NET Plus J... more Atlas ovcjih sireva zemalja zapadnog Balkana predstavlja rezultat međunarodnog SEE-ERA.NET Plus Joint Call projekta naslova: Characterisation and tracking the origin of specific features of traditional cheeses in Western Balkans". Projekt je imao za cilj okupiti istraživacke timove iz Hrvatske, Slovenije, Bosne i Hercegovine i Srbije, u nastojanju definiranja znanstveno-istraživackog sustava za karakterizaciju tradicionalnih sireva zemalja zapadnog Balkana (Istarski, Krcki, Paski ; Bovski, Dolenjski, Kraski ; Livanjski, Travnicki/Vlasicki ; Pirotski, Sjenicki sir). Sustav je ukljucivao standardizaciju tehnoloskog postupka proizvodnje tradicionalnih ovcjih sireva kao i definiranje njihovih fizikalno-kemijskih i senzornih svojstava te dominantnih bakterijskih populacija ukljucenih u proces zrenja karakteristican za svaki pojedini sir.
Journal of Food Science and Technology, 2014
The article title has been published with misspelled entry. The word "sesonal" should be "seasona... more The article title has been published with misspelled entry. The word "sesonal" should be "seasonal". The correct title should be "Volatile compounds in Nanos cheese: their formation during ripening and seasonal variation", as shown above.
Journal of Food Science and Technology, 2014
ABSTRACT The objective of this study was to evaluate the formation of volatile compounds (VCs) du... more ABSTRACT The objective of this study was to evaluate the formation of volatile compounds (VCs) during ripening time in different seasons (summer, winter) of Nanos cheese with Protected Designation of Origin (PDO). The study was also undertaken to compare the aroma profile of feed and milk sampled in two different seasons from the protected area. The VCs analysis was performed by solid-phase micro extraction-gas chromatography–mass spectrometry. Altogether, 62 dif-ferent VCs were detected throughout cheese ripening where their quantity varied with the time of ripening and season. In cheeses from winter season, there was a higher concentration of some fatty acids and esters. Besides, the evaluated differ-ences of cheese samples by season indicated the transfers of some VCs from feed and/or milk into cheese. The most important possible links between cheese with feed and/or milk from different season were found in case of 9 VCs (acetic acid, butanoic acid, 3-methyl butanoic acid, hexanoic acid; ethyl ester of hexanoic acid, -octanoic acid, and -decanoic acid-; 2-butanone, pinane, sabinene) which also define the season. The changes in the amount of some VCs through ripening were significant (e.g. content of some fatty acids and esters increased while content of acetoin and diacetyl decreased). This is the first report which deals with the changes in cheese during ripening influenced by season and feeding system and the transfers of VCs from feed and milk to cheese in the case of traditional Nanos cheese, which was chosen as a model system for other hard type cheeses.
Acta Alimentaria, 2018
This study was undertaken to prepare tailor-made starter culture (TMSC) for Karst ewe's cheese pr... more This study was undertaken to prepare tailor-made starter culture (TMSC) for Karst ewe's cheese production. Therefore, basic technological characteristics (growth ability in milk, acid production, and proteolytic activity) and antistaphylococcal potential were assessed for autochthonous enterococci and lactobacilli. Beside good growth in milk with numbers as high as 8 log CFU ml-1 , certain enterococci and lactobacilli also reduced pH below 5.0 and showed proteolytic activity. In antistaphylococcal testing, only pure strains of enterococci and lactobacilli were moderately antagonistic, but not in coagulated milks and coagulated milk extracts. Enterococci and lactobacilli with most relevant technological/antistaphylococcal properties were combined and tested as TMSC. In control (C) cheese-making, milk was inoculated with TMSC, while staphylococci (SC) cheese-making included contamination with staphylococci. In C trials, high logarithmic counts per g of cheese for enterococci (8.07-8.80) and lactobacilli (7.49-9.98) throughout the ripening period were found, and their authenticity was monitored by RAPD method. Furthermore, cheese extracts failed to inhibit pure cultures of staphylococci, while cheese pieces inhibited Staphylococcus sp. ST17. In SC trials, population dynamics of enterococci (7.81-9.04) and lactobacilli (7.98-9.63) corroborated the results in milk and in C trials, with staphylococci still present at the end of the ripening period but at lower counts than in fresh cheese.
Applied Microbiology and Biotechnology, Sep 18, 2003
Lactobacillus gasseri LF221, an isolate from the feces of a child, produces two bacteriocins. Sta... more Lactobacillus gasseri LF221, an isolate from the feces of a child, produces two bacteriocins. Standard procedures for molecular techniques were used to locate, clone and sequence the fragments of LF221 chromosomal DNA carrying the acidocin LF221 A and B structural genes, respectively. Sequencing analysis revealed the gene of acidocin LF221 A to be an open reading frame encoding a protein composed of 69 amino acids, including a 16-amino-acid N-terminal extension. The acidocin LF221 B gene was found to encode a 65-amino-acid bacteriocin precursor with a 17-amino-acid N-terminal leader peptide. DNA homology searches showed similarities of acidocin LF221 A to brochocin B, lactococcin N and thermophilin B, whereas acidocin LF221 B exhibited some homology to lactacin F and was virtually identical to gassericin X. The peptides encoded by orfA1 and orfB3 showed characteristics of class II bacteriocins and are suspected to be the complementary peptides of acidocin A and B, respectively. orfA3 and orfB5 are proposed to encode putative immunity proteins for the acidocins. Acidocin LF221 A and acidocin LF221 B are predicted to be members of the two-component class II bacteriocins, where acidocin LF221 A appears to be a novel bacteriocin. L. gasseri LF221 is being developed as a potential probiotic strain and a food/feed preservative. Detailed characterization of its acidocins is an important piece of background information useful in applying the strain into human or animal consumption. The genetic information on both acidocins also enables tracking of the LF221 strain in mixed populations and complex environments.
Journal of Food and Nutrition Research, 2018
Mljekarstvo : časopis za unaprjeđenje proizvodnje i prerade mlijeka, Mar 15, 2011
The presence of gene determinants for different bacteriocins has been already demonstrated in tra... more The presence of gene determinants for different bacteriocins has been already demonstrated in traditional Slovenian types of raw milk cheeses 'Tolminc' and 'Kraški'. These genes were present also in the cultivable microbiota. In this research the aim was to establish how the presence of gene determinants for bacteriocins in microbial consortia is reflected in its antimicrobial activity. In addition, one of the goals was to determine whether the strains that carry gene determinants for bacteriocins have any competitive growth advantage in microbial population. Microbial consortium of 'Tolminc' cheese was propagated in milk and examined at the end of propagation its antimicrobial activity and the presence of gene determinants for bacteriocins. Comparison of the results obtained before and after propagation leaded to the conclusion that most of the strains possessing gene determinants for bacteriocins were unable to persist during propagation. The strains which did persist during propagation carried gene determinants for enterocins P, L50B and cytolysin. Antimicrobial activity of consortium before and after propagation was not substantially different and cannot be attributed to any of detected bacteriocins.
DOAJ (DOAJ: Directory of Open Access Journals), Sep 1, 2010
In-situ inhibition of Staphylococcus aureus by lactic acid bacteria consortia from two traditiona... more In-situ inhibition of Staphylococcus aureus by lactic acid bacteria consortia from two traditional Slovenian raw milk cheeses Original scientific paper-Izvorni znanstveni rad UDK: 637.354/579.861.2 Summary Bacteriocin(s) producing lactic acid bacteria naturally present in traditional cheeses represent an inexhaustive pool of microbes with safeguarding potential. Some bacteriocins produced by cheese lactic acid bacteria were already described as successful anti-staphylococcal agents. The presence of genes for bacteriocins with potential anti-staphylococcal activity was also demonstrated in two Slovenian traditional raw milk cheeses, "Tolminc" and "Kraški ovčji sir". Same bacteriocin genes were also detected in viable lactic acid bacteria consortia's isolated from "bacteriocin positive cheeses" on Rogosa, M17 and CATC agar media. The aim of the research was to elucidate whether or not this particular cheese consortia, in which bacteriocin genes were detected, actually exhibit anti-staphylococcal activity in milk and/or cheese. For this purpose different cheese consortia were selected in relation to versatility of detected bacteriocin genes and used to perform challenge tests against Staphylococcus aureus in milk and cheese. In milk following the time/temperature regime of traditional cheese production all cheese consortia effectively inhibited growth of Staphylococcus aureus in the range of app. 2 to 3 log. In cheese the inhibition of staphylococci was less pronounced but still evident since inhibition of app. 1.5 log was detected. Sole inhibition by lactic acid production was ruled out while linking inhibition directly to bacteriocin production would take some additional work.