TY  - CONF
AU  - Stojanović, Sanja
AU  - Stepanović, Jelena
AU  - Ristović, Marina
AU  - Dojnov, Biljana
AU  - Božić, Nataša
AU  - Duduk, Bojan
AU  - Vujčić, Zoran
PY  - 2022
UR  - https://cer.ihtm.bg.ac.rs/handle/123456789/5920
AB  - Fungal inulinases have wide application in industrial biotechnology, and it is presumed that their expression is regulated at the transcriptional level via promoter. It is also known that different sugars have an inducing effect on gene expression in fungal genome, including inulinases. Aim of this work was to determine which of the sugars used in growth medium, as the only carbon source, induce the extracellular exoinulinase gene inuE expression in Aspergillus welwitschiae FAW1. Inulin, rafinose, sucrose, glucose and fructose were used as carbon sources, and expression of inuE was monitored during 72 h of cultivation (tested after 24, 36, 48 and 72 h). Both, presence of mRNA in the mycelia and extracellular enzyme activity in the growth media were monitored. Interestingly,
obtained results showed that inuE was induced by fructose, sucrose and rafinose and not by inulin. In all cases, the highest mRNA was detected after 24 h of cultivation, while extracellular exoinulinase activity increased from 24 h with a peak in 72 h. Further experiments are necessary for a comprehensive understanding of the regulation mechanisms of AweinuE promoter for its more purposeful application in biotechnology.
PB  - University of Belgrade - Faculty of Chemistry
PB  - Serbian Biochemical Society
C3  - Proceedings - XI Conference of Serbian Biochemical Society "Amazing Biochemistry", 22.09.2022. Novi Sad, Serbia, 2022
T1  - Exoinulinase gene expression in Aspergillus welwitschiae FAW1 induced by different carbon sources
SP  - 141
UR  - https://hdl.handle.net/21.15107/rcub_cer_5920
ER  - 

@conference{
author = "Stojanović, Sanja and Stepanović, Jelena and Ristović, Marina and Dojnov, Biljana and Božić, Nataša and Duduk, Bojan and Vujčić, Zoran",
year = "2022",
abstract = "Fungal inulinases have wide application in industrial biotechnology, and it is presumed that their expression is regulated at the transcriptional level via promoter. It is also known that different sugars have an inducing effect on gene expression in fungal genome, including inulinases. Aim of this work was to determine which of the sugars used in growth medium, as the only carbon source, induce the extracellular exoinulinase gene inuE expression in Aspergillus welwitschiae FAW1. Inulin, rafinose, sucrose, glucose and fructose were used as carbon sources, and expression of inuE was monitored during 72 h of cultivation (tested after 24, 36, 48 and 72 h). Both, presence of mRNA in the mycelia and extracellular enzyme activity in the growth media were monitored. Interestingly,
obtained results showed that inuE was induced by fructose, sucrose and rafinose and not by inulin. In all cases, the highest mRNA was detected after 24 h of cultivation, while extracellular exoinulinase activity increased from 24 h with a peak in 72 h. Further experiments are necessary for a comprehensive understanding of the regulation mechanisms of AweinuE promoter for its more purposeful application in biotechnology.",
publisher = "University of Belgrade - Faculty of Chemistry, Serbian Biochemical Society",
journal = "Proceedings - XI Conference of Serbian Biochemical Society "Amazing Biochemistry", 22.09.2022. Novi Sad, Serbia, 2022",
title = "Exoinulinase gene expression in Aspergillus welwitschiae FAW1 induced by different carbon sources",
pages = "141",
url = "https://hdl.handle.net/21.15107/rcub_cer_5920"
}

Stojanović, S., Stepanović, J., Ristović, M., Dojnov, B., Božić, N., Duduk, B.,& Vujčić, Z.. (2022). Exoinulinase gene expression in Aspergillus welwitschiae FAW1 induced by different carbon sources. in Proceedings - XI Conference of Serbian Biochemical Society "Amazing Biochemistry", 22.09.2022. Novi Sad, Serbia, 2022
University of Belgrade - Faculty of Chemistry., 141.
https://hdl.handle.net/21.15107/rcub_cer_5920

Stojanović S, Stepanović J, Ristović M, Dojnov B, Božić N, Duduk B, Vujčić Z. Exoinulinase gene expression in Aspergillus welwitschiae FAW1 induced by different carbon sources. in Proceedings - XI Conference of Serbian Biochemical Society "Amazing Biochemistry", 22.09.2022. Novi Sad, Serbia, 2022. 2022;:141.
https://hdl.handle.net/21.15107/rcub_cer_5920 .

Stojanović, Sanja, Stepanović, Jelena, Ristović, Marina, Dojnov, Biljana, Božić, Nataša, Duduk, Bojan, Vujčić, Zoran, "Exoinulinase gene expression in Aspergillus welwitschiae FAW1 induced by different carbon sources" in Proceedings - XI Conference of Serbian Biochemical Society "Amazing Biochemistry", 22.09.2022. Novi Sad, Serbia, 2022 (2022):141,
https://hdl.handle.net/21.15107/rcub_cer_5920 .

TY  - JOUR
AU  - Stojanović, Sanja
AU  - Ristović, Marina
AU  - Stepanović, Jelena
AU  - Margetić, Aleksandra
AU  - Duduk, Bojan
AU  - Vujčić, Zoran
AU  - Dojnov, Biljana
PY  - 2022
UR  - https://cer.ihtm.bg.ac.rs/handle/123456789/5360
AB  - Production of fructooligosaccharides (FOS) is a trending topic due to their prebiotic effect becoming increasingly important for the modern human diet. The most suitable process for FOS production is the one using fungal inulinases. Introduction of new fungal inulinase producers and their implementation in production of inulinase enzymes is therefore gaining interest. This study provides a new approach to FOS synthesis by fungal enzyme complex without prior separation of any specific enzyme. Inulinase enzyme complexes could be used for the synthesis of FOS in two possible ways – hydrolysis of inulin (FOSh) and transfructosylation process of sucrose (FOSs), as demonstrated here. Depending on the fungal growth inducing substrate, a variety of inulinase enzyme complexes was obtained – one of which was most successful in production of FOSh and another one of FOSs. Substrates derived from crops: triticale, wheat bran, Jerusalem artichoke and Aspergillus welwitschiae isolate, previously proven as safe for use in food, were utilized for production of inulinase enzyme cocktails. The highest FOSs production was obtained by enzyme complex rich in β-fructofuranosidase, while the highest FOSh production was obtained by enzyme complex rich in endoinulinase. Both FOSh and FOSs showed antioxidant potential according to ABTS and ORAC, which classifies them as a suitable additive in functional food. Simultaneous zymographic detection of inulinase enzymes, which could contribute to expansion of the knowledge on fungal enzymes, was developed and applied here. It demonstrated the presence of different inulinase isoforms depending on fungal growth substrate. These findings, which rely on the innate ability of fungi to co-produce all inulinases from a cocktail, could be useful as a new, easy approach to FOS production by fungal enzymes without their separation and purification, contributing to cheaper and faster production processes.
PB  - Elsevier
T2  - Food Research International
T1  - Aspergillus welwitschiae inulinase enzyme cocktails obtained on agro-material inducers for the purpose of fructooligosaccharides production
VL  - 160
SP  - 111755
DO  - 10.1016/j.foodres.2022.111755
ER  - 

@article{
author = "Stojanović, Sanja and Ristović, Marina and Stepanović, Jelena and Margetić, Aleksandra and Duduk, Bojan and Vujčić, Zoran and Dojnov, Biljana",
year = "2022",
abstract = "Production of fructooligosaccharides (FOS) is a trending topic due to their prebiotic effect becoming increasingly important for the modern human diet. The most suitable process for FOS production is the one using fungal inulinases. Introduction of new fungal inulinase producers and their implementation in production of inulinase enzymes is therefore gaining interest. This study provides a new approach to FOS synthesis by fungal enzyme complex without prior separation of any specific enzyme. Inulinase enzyme complexes could be used for the synthesis of FOS in two possible ways – hydrolysis of inulin (FOSh) and transfructosylation process of sucrose (FOSs), as demonstrated here. Depending on the fungal growth inducing substrate, a variety of inulinase enzyme complexes was obtained – one of which was most successful in production of FOSh and another one of FOSs. Substrates derived from crops: triticale, wheat bran, Jerusalem artichoke and Aspergillus welwitschiae isolate, previously proven as safe for use in food, were utilized for production of inulinase enzyme cocktails. The highest FOSs production was obtained by enzyme complex rich in β-fructofuranosidase, while the highest FOSh production was obtained by enzyme complex rich in endoinulinase. Both FOSh and FOSs showed antioxidant potential according to ABTS and ORAC, which classifies them as a suitable additive in functional food. Simultaneous zymographic detection of inulinase enzymes, which could contribute to expansion of the knowledge on fungal enzymes, was developed and applied here. It demonstrated the presence of different inulinase isoforms depending on fungal growth substrate. These findings, which rely on the innate ability of fungi to co-produce all inulinases from a cocktail, could be useful as a new, easy approach to FOS production by fungal enzymes without their separation and purification, contributing to cheaper and faster production processes.",
publisher = "Elsevier",
journal = "Food Research International",
title = "Aspergillus welwitschiae inulinase enzyme cocktails obtained on agro-material inducers for the purpose of fructooligosaccharides production",
volume = "160",
pages = "111755",
doi = "10.1016/j.foodres.2022.111755"
}

Stojanović, S., Ristović, M., Stepanović, J., Margetić, A., Duduk, B., Vujčić, Z.,& Dojnov, B.. (2022). Aspergillus welwitschiae inulinase enzyme cocktails obtained on agro-material inducers for the purpose of fructooligosaccharides production. in Food Research International
Elsevier., 160, 111755.
https://doi.org/10.1016/j.foodres.2022.111755

Stojanović S, Ristović M, Stepanović J, Margetić A, Duduk B, Vujčić Z, Dojnov B. Aspergillus welwitschiae inulinase enzyme cocktails obtained on agro-material inducers for the purpose of fructooligosaccharides production. in Food Research International. 2022;160:111755.
doi:10.1016/j.foodres.2022.111755 .

Stojanović, Sanja, Ristović, Marina, Stepanović, Jelena, Margetić, Aleksandra, Duduk, Bojan, Vujčić, Zoran, Dojnov, Biljana, "Aspergillus welwitschiae inulinase enzyme cocktails obtained on agro-material inducers for the purpose of fructooligosaccharides production" in Food Research International, 160 (2022):111755,
https://doi.org/10.1016/j.foodres.2022.111755 . .

TY  - JOUR
AU  - Stojanović, Sanja
AU  - Stepanović, Jelena
AU  - Špirović Trifunović, Bojana
AU  - Duduk, Nataša
AU  - Dojnov, Biljana
AU  - Duduk, Bojan
AU  - Vujčić, Zoran
PY  - 2022
UR  - https://cer.ihtm.bg.ac.rs/handle/123456789/5585
AB  - Research background. Inulinases are used for fructooligosaccharide production and they are of interest for both scientific community and industry. Black aspergilli represent a diverse group of species that has use for enzyme production, in particular some species are known as potent inulinase producers. Finding new potential producers from the environment is as important as improving the production with known strains. Safe use of enzymes produced by aspergilli in food industry is placed ahead of their benefit for inulinase production.  Experimental approach. Here we show a specific approach to finding/screening of newly isolated fungal inulinase producers that combines a newly developed screening method and an equally important assessment of the toxigenic potential of the fungus. In this study 39 black aspergilli collected from different substrates in Serbia were identified and assessed for inulinase production.  Results and conclusions. The most common species were Aspergillus tubingensis (51.2 %), followed by A. niger (23.1 %), A. welwitschiae (23.1 %) and A. uvarum (2.6 %). The isolates for inulinase production were selected using a cheap and easy, fast and non-hazardous alternative inulinase screening test developed in this work. Enzymatic activity of selected inulinase-producing strains was confirmed spectrophotometrically. Since some A. niger and A. welwitschiae strains are able to produce mycotoxins ochratoxin A (OTA) and fumonisins (FB), the toxigenic potential of selected inulinase producers was assessed analytically and genetically. Fungal enzyme producer can be considered safe for use in food industry only after comparing the results of both approaches for investigating toxic potential, the direct presence of mycotoxins in the enzyme preparation (analytically) and the presence of mycotoxin gene clusters (genetically). In some strains the absence of OTA and FB production capability was molecularly confirmed by the absence of complete or critical parts of biosynthetic gene clusters, respectively. The two best inulinase producers and mycotoxin non-producers (without mycotoxin production capability as additional safety) were selected as potential candidates for further development of enzyme production.  Novelty and scientific contribution. The presented innovative approach for the selection of potential fungal enzyme producer shows that only non-toxigenic fungi could be considered as useful in food industry. Although this study was done on local isolates, the approach is applicable globally.
PB  - Faculty of Food Technology and Biotechnology - University of Zagreb
T2  - Food Technology and Biotechnology
T1  - Selection of Non-Mycotoxigenic Inulinase Producers in the Group of Black Aspergilli for Use in Food Processing
VL  - 60
IS  - 4
SP  - 421
EP  - 433
DO  - 10.17113/ftb.60.04.22.7521
ER  - 

@article{
author = "Stojanović, Sanja and Stepanović, Jelena and Špirović Trifunović, Bojana and Duduk, Nataša and Dojnov, Biljana and Duduk, Bojan and Vujčić, Zoran",
year = "2022",
abstract = "Research background. Inulinases are used for fructooligosaccharide production and they are of interest for both scientific community and industry. Black aspergilli represent a diverse group of species that has use for enzyme production, in particular some species are known as potent inulinase producers. Finding new potential producers from the environment is as important as improving the production with known strains. Safe use of enzymes produced by aspergilli in food industry is placed ahead of their benefit for inulinase production.  Experimental approach. Here we show a specific approach to finding/screening of newly isolated fungal inulinase producers that combines a newly developed screening method and an equally important assessment of the toxigenic potential of the fungus. In this study 39 black aspergilli collected from different substrates in Serbia were identified and assessed for inulinase production.  Results and conclusions. The most common species were Aspergillus tubingensis (51.2 %), followed by A. niger (23.1 %), A. welwitschiae (23.1 %) and A. uvarum (2.6 %). The isolates for inulinase production were selected using a cheap and easy, fast and non-hazardous alternative inulinase screening test developed in this work. Enzymatic activity of selected inulinase-producing strains was confirmed spectrophotometrically. Since some A. niger and A. welwitschiae strains are able to produce mycotoxins ochratoxin A (OTA) and fumonisins (FB), the toxigenic potential of selected inulinase producers was assessed analytically and genetically. Fungal enzyme producer can be considered safe for use in food industry only after comparing the results of both approaches for investigating toxic potential, the direct presence of mycotoxins in the enzyme preparation (analytically) and the presence of mycotoxin gene clusters (genetically). In some strains the absence of OTA and FB production capability was molecularly confirmed by the absence of complete or critical parts of biosynthetic gene clusters, respectively. The two best inulinase producers and mycotoxin non-producers (without mycotoxin production capability as additional safety) were selected as potential candidates for further development of enzyme production.  Novelty and scientific contribution. The presented innovative approach for the selection of potential fungal enzyme producer shows that only non-toxigenic fungi could be considered as useful in food industry. Although this study was done on local isolates, the approach is applicable globally.",
publisher = "Faculty of Food Technology and Biotechnology - University of Zagreb",
journal = "Food Technology and Biotechnology",
title = "Selection of Non-Mycotoxigenic Inulinase Producers in the Group of Black Aspergilli for Use in Food Processing",
volume = "60",
number = "4",
pages = "421-433",
doi = "10.17113/ftb.60.04.22.7521"
}

Stojanović, S., Stepanović, J., Špirović Trifunović, B., Duduk, N., Dojnov, B., Duduk, B.,& Vujčić, Z.. (2022). Selection of Non-Mycotoxigenic Inulinase Producers in the Group of Black Aspergilli for Use in Food Processing. in Food Technology and Biotechnology
Faculty of Food Technology and Biotechnology - University of Zagreb., 60(4), 421-433.
https://doi.org/10.17113/ftb.60.04.22.7521

Stojanović S, Stepanović J, Špirović Trifunović B, Duduk N, Dojnov B, Duduk B, Vujčić Z. Selection of Non-Mycotoxigenic Inulinase Producers in the Group of Black Aspergilli for Use in Food Processing. in Food Technology and Biotechnology. 2022;60(4):421-433.
doi:10.17113/ftb.60.04.22.7521 .

Stojanović, Sanja, Stepanović, Jelena, Špirović Trifunović, Bojana, Duduk, Nataša, Dojnov, Biljana, Duduk, Bojan, Vujčić, Zoran, "Selection of Non-Mycotoxigenic Inulinase Producers in the Group of Black Aspergilli for Use in Food Processing" in Food Technology and Biotechnology, 60, no. 4 (2022):421-433,
https://doi.org/10.17113/ftb.60.04.22.7521 . .

TY  - CONF
AU  - Stojanović, Sanja
AU  - Stepanović, Jelena
AU  - Margetić, Aleksandra
AU  - Duduk, Nataša
AU  - Dojnov, Biljana
AU  - Vujčić, Zoran
AU  - Duduk, Bojan
PY  - 2021
UR  - https://cer.ihtm.bg.ac.rs/handle/123456789/5816
AB  - Fructooligosaccharides (FOS) are used in the human diet thanks to their prebiotic effect and they are generally regarded as safe [1]. The increase in the functional food that contains prebiotics, has been tremendous over the last two decades. The most suitable process for FOS synthesis is by enzymes [2], particularly the one produced by filamentous fungi from the genus Aspergillus [2,3]. Aspergillus welwitschiae FAW1 strain, isolated from the environment, has proven to be non-toxigenic and safe for use in food production. Moreover, the absence of ochratoxins and fumonisins production capability was molecularly confirmed by the absence of complete or critical parts of biosynthetic gene clusters. Growing fungi on the natural substrate, triticale (Triticosecale sp), led to the production of various enzymes from inulinase complex (InuA, InuE, FTase, FFase). Production of FOS has been tested in two possible ways with the obtained inulinase enzyme complex: (1) synthesis from sucrose – fructosyltransferase activity and (2) hydrolysis of inulin – endoinulinase and exoinulinase activity. The obtained FOS were detected by TLC and HPLC methods and characterized by examination of antioxidant capacity. Produced FOS showed significant antioxidant potential according to ABTS and ORAC which classifies them as important additives in functional food. These findings open up opportunities for an easy approach for FOS production by fungal inulinase enzymes, without their prior separation and purification.
PB  - Sociedade Portuguesa de Química
C3  - Book of abstracts - XXI EuroFoodChem Conference, 22-24 November 2021, on-line
T1  - Production of fructooligosaccharides by Aspergillus welwitschiae inulinase enzyme complex, obtained on natural substrate
SP  - 172
UR  - https://hdl.handle.net/21.15107/rcub_cer_5816
ER  - 

@conference{
author = "Stojanović, Sanja and Stepanović, Jelena and Margetić, Aleksandra and Duduk, Nataša and Dojnov, Biljana and Vujčić, Zoran and Duduk, Bojan",
year = "2021",
abstract = "Fructooligosaccharides (FOS) are used in the human diet thanks to their prebiotic effect and they are generally regarded as safe [1]. The increase in the functional food that contains prebiotics, has been tremendous over the last two decades. The most suitable process for FOS synthesis is by enzymes [2], particularly the one produced by filamentous fungi from the genus Aspergillus [2,3]. Aspergillus welwitschiae FAW1 strain, isolated from the environment, has proven to be non-toxigenic and safe for use in food production. Moreover, the absence of ochratoxins and fumonisins production capability was molecularly confirmed by the absence of complete or critical parts of biosynthetic gene clusters. Growing fungi on the natural substrate, triticale (Triticosecale sp), led to the production of various enzymes from inulinase complex (InuA, InuE, FTase, FFase). Production of FOS has been tested in two possible ways with the obtained inulinase enzyme complex: (1) synthesis from sucrose – fructosyltransferase activity and (2) hydrolysis of inulin – endoinulinase and exoinulinase activity. The obtained FOS were detected by TLC and HPLC methods and characterized by examination of antioxidant capacity. Produced FOS showed significant antioxidant potential according to ABTS and ORAC which classifies them as important additives in functional food. These findings open up opportunities for an easy approach for FOS production by fungal inulinase enzymes, without their prior separation and purification.",
publisher = "Sociedade Portuguesa de Química",
journal = "Book of abstracts - XXI EuroFoodChem Conference, 22-24 November 2021, on-line",
title = "Production of fructooligosaccharides by Aspergillus welwitschiae inulinase enzyme complex, obtained on natural substrate",
pages = "172",
url = "https://hdl.handle.net/21.15107/rcub_cer_5816"
}

Stojanović, S., Stepanović, J., Margetić, A., Duduk, N., Dojnov, B., Vujčić, Z.,& Duduk, B.. (2021). Production of fructooligosaccharides by Aspergillus welwitschiae inulinase enzyme complex, obtained on natural substrate. in Book of abstracts - XXI EuroFoodChem Conference, 22-24 November 2021, on-line
Sociedade Portuguesa de Química., 172.
https://hdl.handle.net/21.15107/rcub_cer_5816

Stojanović S, Stepanović J, Margetić A, Duduk N, Dojnov B, Vujčić Z, Duduk B. Production of fructooligosaccharides by Aspergillus welwitschiae inulinase enzyme complex, obtained on natural substrate. in Book of abstracts - XXI EuroFoodChem Conference, 22-24 November 2021, on-line. 2021;:172.
https://hdl.handle.net/21.15107/rcub_cer_5816 .

Stojanović, Sanja, Stepanović, Jelena, Margetić, Aleksandra, Duduk, Nataša, Dojnov, Biljana, Vujčić, Zoran, Duduk, Bojan, "Production of fructooligosaccharides by Aspergillus welwitschiae inulinase enzyme complex, obtained on natural substrate" in Book of abstracts - XXI EuroFoodChem Conference, 22-24 November 2021, on-line (2021):172,
https://hdl.handle.net/21.15107/rcub_cer_5816 .