Storage molds and their mycotoxins

Glavnina rasti in tvorbe toksinov skladiščnih plesni poteka po spravilu pridelka, vendar pridejo plesni v stik z rastlinami že na polju ali ob spravilu pridelka. Najpomembnejše vrste skladiščnih plesni spadajo v rodova Aspergillus in Penicillium. Glavni predstavnici iz rodu Aspergillus sta glivi A. flavus in A. parasiticus. Obe lahko tvorita AFB1 in AFB2. Iz omenjenega rodu poznamo še skladiščne plesni vrst A. ochraceus, A. westerdijkiae, A. steynii, A. carbonarius in A. niger, ki lahko tvorijo ohratoksine, vendar žita redko okužijo. Edini odkriti vrsti gliv iz rodu Penicillium, ki lahko tvorita ohratoksine, sta P. verrucosum in P. nordicum. P. verrucosum je bolj pogosta skladiščna plesen in jo najdemo izključno na žitu. Tvorba toksinov za glive ni esencialnega pomena in se začne ob za glivo stresnih pogojih. Mikotoksini so škodljivi zdravju ljudi in živali. Nekateri izmed njih so rakotvorni. Glavni predstavniki mikotoksinov, ki jih najdemo na žitu in žitnih izdelkih, so aflatoksini in ohratoksini. Glavni ukrep za zaviranje rasti skladiščnih plesni in tvorbe mikotoksinov je zagotavljanje ustreznih skladiščnih pogojev. Potrebno je uravnavanje temperature in vlage. Koristen preventivni ukrep za zagotavljanje higienske neoporečnosti hrane in krme je tudi čiščenje luske zrnja in ločevanje primesi, poškodovanih in plesnivih zrn od navidezno zdrave žitne mase.Most of the growth and mycotoxin production of the storage molds takes place after the harvesting, but the mold comes into contact with plants already in the field or at harvesting.. The most important storage fungi species originate from genuses Aspergillus and Penicillium. The major two species from Aspergillus genus are A. flavus and A. parasiticus. Both can produce AFB1 and AFB2. A. ochraceus, A. westerdijkiae, A. steynii, A. carbonarius and A. niger are also known as storage fundi. They all can produce ochratoxins, but we rarely find them on grains. The only known ochratoxin producing species from Penicillium genus are P. verrucosum and P. nordicum. P. verrucosum is more common from the two and we typically find it on grains. Mycotoxin production isn’t essential. It starts when fungi are in stress. Mycotoxins can harm human and animal health. Some of them are cancerogenic. The most important mycotoxins found on grains and grain products are aflatoxins and ochratoxins. The major strategy for reducing fungal growth and mycotoxin production is providing adequate storage facilities. Controlling temperature and humidity is necessary. An useful measure for providing pristine food and feed is rinsing the grains surface and sorting foreign particles, moldy or damaged grains from healthy looking grain mass