Genetic and phenotypic variation of Fusarium proliferatum isolates from different host species

Fusarium proliferatum (Matsushima) Nirenberg is a common pathogen infecting numerous crop plants and occurring in various climatic zones. It produces large amounts of fumonisins, a group of polyketide-derived mycotoxins. Fumonisin biosynthesis is determined by the presence and activity of the FUM cluster, several co-regulated genes with a common expression pattern. In the present work, we analyzed 38 F. proliferatum isolates from different host plant species, demonstrating host-specific polymorphisms in partial sequences of the key FUM1 gene (encoding polyketide synthase). We also studied growth rates across different temperatures and sample origin and tried to establish the relationships between DNA sequence polymorphism and toxigenic potential. Phylogenetic analysis was conducted based on FUM1 and tef-1α sequences for all isolates. The results indicated the greatest variations of both toxigenic potential and growth patterns found across the wide selection of isolates derived from maize. Fumonisin production for maize isolates ranged from 3.74 to 4,500 μg/g of fumonisin B1. The most efficient producer isolates obtained from other host plants were only able to synthesize 1,820–2,419 μg/g of this metabolite. A weak negative rank correlation between fumonisin content and isolate growth rates was observed. All garlic-derived isolates formed a distinct group on a FUM1-based dendrogram. A second clade consisted of tropical and sub-tropical strains (isolated from pineapple and date palm). Interestingly, isolates with the fastest growth patterns were also grouped together and included both isolates originating from rice. The sequence of the FUM1 gene was found to be useful in revealing the intraspecific polymorphism, which is, to some extent, specifically correlated with the host plant

MIKOTOKSINI U HRANI, KRMNIM SMJESAMA I KRMIVIMA

Mycotoxins are toxic secondary metabolites formed by toxigenic fungi present in foods, feeds and their components. Since the presence of the above men¬tioned microorganisms is unavoidable, mold growth is an inevitable consequence of conditions advantageous for fungi development (water content and temperature) found in case of specific food and feed technologies. Mycotoxins identified up to now (several hundred) are molecules of different chemical structures and molecular weight up to 500 Da. An attempt to explain why biosynthesis of so many toxic metabolites – are the consequence of primary metabolism – is necessary for fungi will be discussed. Exposure of human beings and animals to the above compounds causes undesirable effects, with a broad variety of biological effects and – as a consequence – chronic diseases called mycotoxicoses. The most important genera of toxigenic and pathogenic fungi Aspergillus, Fusarium and Penicillium will be characterized, especially concerning conditions of rapid growth and development followed by biosynthesis of a variety of mycotoxins.The above microorganisms are related – during vegetation – to plant oxidative stress induced by weather and environment conditions. The above as well as biosynthesis of the metabolites will be discussed. Rapid development of fungi followed by toxin formation causes a reduction of crop yields, a deterioration of their quality and as a consequence results in significant economic losses, as worldwide approximately 25% of crops are affected by mycotoxins annually. Presented results will confirm that six metabolites (aflatoxins B1, ZEA, DON, fumonisins, T-2 toxin and OTA) in diverse materials (matrices) repre¬sent a real problem throughout the world. Occurrence and concentration levels are variable for different mycotoxins and are closely related to the weather conditions and plant stress responsible for the metabolite formation, which will be highlighted. Levels of safety will be discussed with the emphasis on low doses which cause subclinical losses. Most of the diseases occur after consumption of mycotoxin-contaminated grains or their products, but other routes of exposure also exist. The diagnosis of mycotoxicoses is dependent upon adequate testing for mycotoxins, involving sampling, sample preparation and analysis. Information on mycotoxin contamination of foods, feeds and their components as well as relevant data on new sources of contamination will be given. Methods of decontamination are usually difficult, so prevention of mycotoxin formation is of prime concern. Results on breeding of cereal varieties resistant to pathogenic fungi and biosynthesis of toxic secondary metabolites (mycotoxins) will be presented with an emphasis on the reduction of human and animal health risk. Recent results indicating the importance of mycotoxins in Poland (compared to world data) are planned to be discussed.Mikotoksini su toksični sekundarni metaboliti koje stvaraju toksigene gljivice što se nalaze u hrani, krmnim smjesama i krmivima. Budući da je postojanje ovih mikroorganizama neizbježivo, rast plijesni je neizbježna posljedica povoljnih uvjeta za razvoj gljivica (sadržaj vode i temperatura) u specifičnim tehnologijama hrane i krmiva. Dosad identificirani mikotoksini (nekoliko stotina) su molekule različitih kemijskih struktura i molekularne težine do 500 Da. U radu će se raspravljati o pokušaju objašnjenja zašto je za gljivice potrebna biosinteza tolikih toksičnih metabolita - kao posljedica primarnog metabolizma. Izlaganje ljudi i životinja navedenim komponentama uzrokuje nepoželjne učinke i mnogo različitih bioloških učinaka te kao posljedicu kronične bolesti zvane mikotoksikoze. Opisat će se najvažnije vrste toksigenih i patogenih gljivica Aspergillus, Fusarium i Penicillium, osobito uvjeti brzog rasta i razvoja te biosinteza raznih mikotoksina. Gore navedeni mikroorganizmi u vezi su za vrijeme vegetacije s oksidativnim stresom biljke izazvanim vremenskim i okolišnim uvjetima. Raspravljat će se o ovome, kao i o biosintezi metabolita. Brzi razvoj gljivica te stvaranje toksina uzrokuje smanjenje prinosa usjeva, pad njihove kvalitete, te kao posljedicu, znatne privredne gubitke budući da je širom svijeta godišnje oko 25% usjeva zahvaćeno mikotoksinima. Izneseni podaci će potvrditi da šest metabolita (aflatoksini, B1, ZEA, DON, fumonizini, toksin T-2 i OTA) u različitim materijalima (matricama) predstavljaju stvarni problem u čitavom svijetu. Pojava i razine koncentracije variraju za razne mikotoksine i usko su povezane s vremenskim uvjetima i stresom biljke, odgovornima za stvaranje metabolita. Govorit će se o razinama sigurnosti s težištem na niskim dozama, što uzrokuje subkliničke gubitke. Većina bolesti pojavljuje se nakon konzumiranja različitog zrnja ili njihovih proi zvoda zaraženih mikotoksinima, ali postoje i drugi načini izlaganja. Dijagnoziranje mikotoksikoza ovisi o odgovarajućem testiranju na mikotoksine uključujući uzorkovanje, pripremu uzoraka i analizu. Govorit će se o zaraženosti hrane, krmnih smjesa i krmiva mikotoksinima te dati i odgovarajući podaci o novim izvorima zaraze. Metode dekontaminacije su obično teške pa je sprječavanje stvaranja mikotoksina od prvenstvene važnosti. Bit će predstavljeni rezultati istraživanja niza žitarica otpornih na patogene gljivice i biosinteza toksičnih sekundarnih metabolita (mikotoksina) s naglaskom na smanjenje rizika za zdravlje ljudi i životinja. Predmet rasprave bit će najnoviji rezultati što upućuju na važnost mikotoksina u Poljskoj (u usporedbi s podacima u svijetu)

Uloga pročišćavanja otpadnih voda u smanjenju onečišćenja površinskih voda zearalenonom

Zearalenone (ZEA) is a mycotoxin produced by some Fusarium species in food and feed. The toxicity of ZEA and its metabolites is related to the chemical structure of the mycotoxin, which is similar to naturally occurring oestrogens. Currently, there is increasing awareness of the presence of fungi and their toxic metabolites in the aquatic environment. One of the sources of these compounds are the effluents from wastewater treatment plants. The average annual efficiency of zearalenone reduction in the Łęczyca plant in our three-year study was in the range from 51.35 to 69.70 %. The three-way analysis of variance (year, month, and kind of wastewater) shows that the main effects of all factors and all interactions between them were significant for zearalenone and dissolved organic carbon content. Our findings suggest that wastewater is not the main source of surface water pollution with zearalenone. Future research should investigate the means to reduce ZEA and its migration from the fields through prevention strategies such as breeding for crops, plant debris management (crop rotation, tillage), and/or chemical and biological control.Zearalenon (ZEA) je mikotoksin koji u hrani proizvode neke vrste gljivica roda Fusarium. Njegova toksičnost i toksičnost njegovih metabolita ovisi o kemijskoj strukturi mikotoksina, a djelovanje mu je slično onome prirodnoga estrogena. Sve smo svjesniji važnosti gljivica i njihovih toksičnih metabolita u vodenom okolišu. Jedan od izvora spoja u površinskim vodama jesu i otpadne vode. Naše je trogodišnje praćenje pokazalo da se uspješnost pročišćenja zearalenona iz otpadnih voda kreće u rasponu od 51,35 do 69,70 % na godišnjoj razini. Trostrana analiza varijance (godina, mjesec, vrsta otpadne vode - nepročišćena/pročišćena) upućuje na to da je djelovanje svih čimbenika i svih njihovih međusobnih interakcija značajno utjecalo na razine zearalenona i otopljenog organskog ugljika. Istraživanje je pokazalo da otpadne vode nisu glavni izvor onečišćenja površinskih voda zearalenonom. Buduća bi istraživanja trebala utvrditi preventivne strategije uzgoja, upravljanja ostacima biljke (rotacijom, obradom zemljišta), odnosno tretiranje kemijskim i biološkim sredstvima kojima bi se smanjile razine zearalenona i njegova migracija s polja u vodeni okoliš

Djelotvornost mliječnokiselinskih bakterija protiv patogenih plijesni i mikotoksina

Mycotoxins are produced by some fungal species of the genera Aspergillus, Penicillium, and Fusarium and are common contaminants of a wide range of food commodities. Numerous strategies are used to minimise fungal growth and mycotoxin contamination throughout the food chain. This review addresses the use of lactic acid bacteria, which can inhibit fungal growth and participate in mycotoxin degradation and/or removal from contaminated food. Being beneficial for human and animal health, lactic acid bacteria have established themselves as an excellent solution to the problem of mycotoxin contamination, yet in practice their application in removing mycotoxins remains a challenge to be addressed by future research.Mikotoksini su sekundarni proizvodi pojedinih vrsta plijesni rodova Aspergillus, Penicillium i Fusarium koji često zagađuju raznovrsne prehrambene proizvode. Stoga se u suzbijanju tih plijesni i zagađenja mikotoksinima primjenjuju mnoge strategije kroz cijeli prehrambeni lanac. U ovome se prikazu raspravlja o primjeni mliječnokiselinskih bakterija, kojima se već stoljećima sprječava razvoj i rast plijesni, a koje sudjeluju i u razgradnji mikotoksina i/ili u njihovu uklanjanju iz zagađene hrane. Budući da su korisne za ljudsko i životinjsko zdravlje, mliječnokiselinske bakterije izvrsno su rješenje problema sa zagađenjem mikotoksinima, ali je njihova primjena još pred izazovima, koje će riješiti buduća istraživanja

Protein and sugar content of tubers in potato plants treated with biostimulants

The use of biostimulants and cultivar selection play an important role in modern potato farming because they influence tuber yield and quality. The nutritional value and processing suitability of potato tubers are affected by their content of total protein, reducing sugars and sucrose. The aim of this study was to determine the effect of biostimulants on the content of total protein, glucose, fructose and sucrose in potato tubers (skin, flesh and whole tubers with skin), at harvest and after 5 months of storage. The experimental materials included tubers of five edible potato cultivars: Irga, Satina, Valfi, Blaue St. Galler and HB Red. During the growing season, potato plants were treated with the following biostimulants: Asahi SL, Bio-Algeen S-90, Kelpak SL and Trifender WP. Control plants were not treated with biostimulants. The total protein content of tubers was determined by the Kjeldahl method. Simple sugars and sucrose were determined by high-performance liquid chromatography. At harvest, total protein concentration was significantly higher in purple- and red-fleshed cultivars than in cream- and yellow-fleshed cultivars. An analysis of tuber parts revealed that flesh had the highest protein content. The total protein content of tubers increased during storage. Biostimulants had no significant effect on total protein concentration in tubers at harvest or after storage. The content of simple sugars and sucrose was higher in the skin, flesh and whole tubers of purple- and red-fleshed cultivars, than in cream- and yellow-fleshed cultivars. Potato tubers with colored flesh accumulated the highest amounts of total sugars. Biostimulants, in particular Bio-Algeen S-90 and Kelpak SL, contributed to the accumulation of monosaccharides and the disaccharide in potato tubers, and, in consequence, total sugars. Their concentrations in potato tubers increased during storage

Pojava mikotoksina u vodenom okolišu zbog njihove prisutnosti u usjevima

The aim of this study was to establish a relation between zearalenone contamination of crops in the Polish province of Wielkopolska and its occurrence in aquatic ecosystems close by the crop fields. Water samples were collected from water bodies such as drainage ditches, wells, or watercourses located in four agricultural areas. Moreover, control water samples were collected from the Bogdanka river, which was located outside the agricultural areas and near an urban area. Cereal samples were collected in the harvest season from each agricultural area close to tested water bodies. Zearalenone (ZEA) was found in all water and cereal samples. The highest concentrations were recorded in the postharvest season (September to October) and the lowest in the winter and spring. Mean ZEA concentrations in water ranged between 1.0 ng L-1 and 80.6 ng L-1, and in cereals from 3.72 ng g-1 to 28.97 ng g-1. Our results confi rm that mycotoxins are transported to aquatic systems by rain water through soil.Cilj ovog istraživanja bio je pojasniti učestalost pojave mikotoksina u vodenim ekosustavima i njihove korelacije sa stupnjem zaraze žitarica (uzgajanih u blizini vodospremnika), čija su zrna onečišćena (kontaminirana) mikotoksinima te problem prolaska mikotoksina kroz tlo u vodeni okoliš (onečišćenje podzemnih voda mikotoksinima). Uzorci vode prikupljeni su u regiji Wielkopolska iz vodenih tijela poput odvodnih jaraka i zdenaca, odnosno vodotoka smještenih u područjima koja se rabe za poljoprivredu. Dio uzoraka vode prikupljen je iz rijeke Bogdanka, u rubnom području grada Poznańa. U sezoni žetve sa svake poljoprivredne površine smještene u neposrednoj blizini testiranih vodenih tijela prikupljeni su uzorci žitarica. U svim analiziranim uzorcima vode i žitarica potvrđena je prisutnost zearalenona (ZEA). Najviše koncentracije mikotoksina u uzorcima sa svih poljoprivrednih površina zabilježene su u jesen nakon sezone žetve (rujan-listopad), dok su najniže vrijednosti izmjerene zimi i u proljeće. Srednje koncentracije zearalenona u vodi bile su u rasponu od 1,0 ng L-1 do 80,6 ng L-1. U žitarica je prosječna razina zearalenona iznosila 3,72 ng g-1 do 28,97 ng g-1, što govori u prilog vjerodostojnosti naše polazišne hipoteze o prijenosu mikotoksina kroz tlo nakon njihova ispiranja s površine u jarke za odvodnju

Differences in Ear Rot Resistance and Fusarium verticillioides-Produced Fumonisin Contamination Between Polish Currently and Historically Used Maize Inbred Lines

Poland is the fifth largest European country, in terms of maize production. Ear rots caused by Fusarium spp. are significant diseases affecting yield and causing grain mycotoxin contamination. Inbred lines, which are commonly used in Polish breeding programs, belong, mostly, to two distinct genetic categories: flint and dent. However, historically used lines belonging to the heterotic Lancaster, IDT and SSS groups were also present in previous Polish breeding programs. In the current study, 98 inbred lines were evaluated across a 2-year-long experiment, after inoculation with F. verticillioides and under natural infection conditions. Lancaster, IDT, SSS and SSS/IDT groups were characterized as the most susceptible ones and flint as the more resistant. Based on the results obtained, the moderately resistant and most susceptible genotypes were defined to determine the content of fumonisins (FBs) in kernel and cob fractions using the HPLC method. Fumonisin's content was higher in the grain samples collected from inoculated plants than in cobs. The association of visible Fusarium symptoms with fumonisin concentration in grain samples was significant. Conversely, the cobs contained more FB1 under natural infection, which may be related to a pathogen's type of growth, infection time or presence of competitive species. Using ddRADseq genome sampling method it was possible to distinguish a basal relationship between moderately resistant and susceptible genotypes. Genetic distance between maize genotypes was high. Moderately resistant inbreed lines, which belong to IDT and IDT/SSS belong to one haplotype. Genotypes which belong to the flint, dent or Lancaster group, and were characterized as moderately resistant were classified separately as the same susceptible one. This research has demonstrated that currently grown Polish inbred lines, as well the ones used in the past are a valid source of resistance to Fusarium ear rot. A strong association was observed between visible Fusarium symptoms with fumonisin concentration in grain samples, suggesting that selection in maize for reduced visible molds should reduce the risk of mycotoxin contamination. NGS techniques provide new tools for overcoming the long selection process and increase the breeding efficiency

The 42nd Symposium Chromatographic Methods of Investigating Organic Compounds : Book of abstracts

The 42nd Symposium Chromatographic Methods of Investigating Organic Compounds : Book of abstracts. June 4-7, 2019, Szczyrk, Polan

Tvorba mikotoksina u vrstama roda Fusarium izoliranim iz biljaka

There is little information on secondary metabolites produced by Fusaria infecting crop plants other than cereals. Many members of Fusarium genus have the ability to colonise perennial crops with only scarce infection or disease symptoms or with no symptoms at all while still being detectable. Even in case of such asymptomatic infection, signifi cant mycotoxin contamination of the plant tissues is possible. The aim of this study was to characterise the spectrum of Fusarium species isolates obtained from different plant hosts (like asparagus, garlic, pineapple, banana, rhubarb, peppers, rice, maize, wheat, and oncidium) and evaluate their ability to biosynthesize the most common mycotoxins in vitro. Among the F. proliferatum isolates, up to 57 % of them biosynthesized fumonisins at very high mass fractions, amounting to above 1000 μg g-1, while other Fusarium species such as F. verticillioides, F. lactis, F. polyphialydicum, F. concentricum, F. temperatum, and F. fujikuroi formed fumonisins mostly at much lower level. Only F. ananatum and F. oxysporum did not produce these toxins. Co-occurrence of FBs with other mycotoxins [moniliformin (MON) and beauvericin (BEA)] was often observed and it was mainly F. proliferatum species that formed both mycotoxins (0.4 μg g-1 to 41.1 μg g-1 BEA and 0.1 μg g-1 to 158.5 μg g-1 MON).Podaci o sekundarnim metabolitima, proizvedenim od plijesni roda Fusarium koje inficiraju druge usjeve osim žitarica, vrlo su oskudni. Premda mnogi članovi roda Fusarium koloniziraju višegodišnje usjeve izazivajući tek oskudnu infekciju, slabe simptome bolesti, a katkad vidljivi simptomi bolesti sasvim izostanu, čak se i u slučaju takve asimptomatske infekcije može otkriti značajna kontaminacija biljnih tkiva mikotoksinima. Cilj ovog istraživanja bio je karakterizirati spektar vrsta roda Fusarium izoliranih iz različitih biljnih domaćina (poput šparoga, češnjaka, ananasa, banana, rabarbare, paprike, riže, kukuruza, pšenice i orhideje) te ocijeniti njihovu sposobnost tvorbe najčešćih mikotoksina u uvjetima in vitro. Utvrdili smo da 57 % izolata F. proliferatum može tvoriti fumonizine s vrlo visokim masenim udjelima, višim od 1000 μg g-1, dok druge vrste roda Fusarium, poput F. verticillioides, F. lactis, F. polyphialydicum, F. concentricum, F. temperatum i F. fujikuroi stvaraju fumonizine s nižim masenim udjelima. Jedino F. ananatum i F. oxysporum ne proizvode spomenute toksine. Nerijetko je zamijećena istodobna pojava fumonizina s ostalim mikotoksinima [moniliformin (MON) i beauvericin (BEA)], a najčešći proizvođač obaju mikotoksina bila je vrsta F. proliferatum (0,4 μg g-1 do 41,1 μg g-1 BEA i 0,1 μg g-1 do 158,5 μg g-1 MON)

Sequence Divergence of the Enniatin Synthase Gene in Relation to Production of Beauvericin and Enniatins in Fusarium Species

Beauvericin (BEA) and enniatins (ENNs) are cyclic peptide mycotoxins produced by a wide range of fungal species, including pathogenic Fusaria. Amounts of BEA and ENNs were quantified in individual rice cultures of 58 Fusarium strains belonging to 20 species, originating from different host plant species and different geographical localities. The species identification of all strains was done on the basis of the tef-1α gene sequence. The main aim of this study was to analyze the variability of the esyn1 gene encoding the enniatin synthase, the essential enzyme of this metabolic pathway, among the BEA- and ENNs-producing genotypes. The phylogenetic analysis based on the partial sequence of the esyn1 gene clearly discriminates species producing exclusively BEA from those synthesizing mainly enniatin analogues