Fumonisins

Fumonisins have been isolated of the fungus Fusarium moniliforme MRC 826 from com intended for human consumption in Transkei, South Africa 190, 191) (Fig. 5.1 192,193), Table 5.1). 

Erase et al., The Chemistry of Mycotoxins, Progress in the Chemistry of Organic Natural Products, Vol. 97, DOI 10.1007/978-3-7091-1312-7 5, 

The structures of the fumonisins were first characterized in 1988 by Benzuidenhout et al. (194). Fumonisin Bi (249) is one of the major fumonisin representatives in culture and in naturally contaminated samples (195-197). Seven other fumonisins - B2, B3, B4, Ai, A2, A3, and A4 (250-256) have been isolated the A-series are A -acetates of fumonisins Bi - B4 (249-252) and appear not to be toxic. 

The analogues, fumonisins Ci - C4 (257-260), fotmd in 1993 by Branham and Planner et al. (198), exhibit the loss of the terminal methyl group, but constitute less than 5% of all fumonisins in terms of their natural abundance. 

In 1996, Musser et al. reported the isolation and characterization of a new series of fumonisins, the P series (261-264), in which the amine of the B series is replaced with an A-linked 3-hydroxypyridinium moiety (199). 

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Many natural products are charged substances, and can be isolated by IEC methods. Dufresne has published a comprehensive review describing various resins and column operating conditions applicable to purification of natural products from fermentation broths or crude extracts.168 Among natural products, antibiotics are of special interest due to their widespread use in humans and animals. Sample cleanup by IEC prior to analysis by other LC methods for quantitative determination of antibiotics in biological fluids is frequent.I69171 Also, IEC followed by TLC appears useful for the quantitation of fumonisin Bl, a mycotoxin found in agricultural products.172... 

Karuna, R. and Sashidhar, R. B., Use of ion-exchange chromatography coupled with TLC-laser scanning densitometry for the quantitation of fumonisin Bl,... 

Fusarium species Trichothecenes Zearalenone Fumonisins Moniliformin... 

Fusarium moniliforme sya verticillioides causes the so-called ear rot disease in maize and produces fumonisin B, (IB,), one of the most frequently detected mycotoxins in the food supply chain worldwide (Steyn, 1995). FBi can inhibit lipid formation, particularly in the liver. Fumonisins have been detected and investigated only relatively recently. Several structurally related forms of fumonisins (FBS) have been associated with human cancer (e.g. FB with oesophageal cancer) as well as with a host of problems in livestock fed with FB -contaminated feed (D Mello, 2003 Benbrook, 2005). 

Abdel-Wahhab M A, Hassan A M, Armer H A and Naguib K M (2004), Prevention of fumonisin-induced maternal and developmental toxicity in rats by certain plant extracts , J. Appl. Toxicol., 24 (6), 469-474. 

Mullett W., Edward P.C., Yeung M.J., Immunoassay of fumonisins by a surface plasmon resonance biosensor, Analytical Biochemistry 1998 258 161-167. 

Velluti A, Marin S, Bettucci L, Ramos AJ, Sanchis V (2000) The effect of fungal competition on colonization of maize grain by Fusarium moniliforme, F. proliferatum and F. graminearum and on fumonisin B and zearalenone formation. Int J Food Microbiol 59 59-66... 

Abbreviations CL, cardioUpin CDase, ceramidase Cer, Ceramide dhCer, dihydroceramide FBI, fumonisin Bl PA, phosphatidic acid PS, phosphatidylserine phytoCer, phytoceramide SPH, sphingosine SIP, sphingosine-1-phosphate. 

Biochemical characterization of the reverse activity of rat brain ceramidase A CoA-independent and fumonisin B1 insensitive ceramide synthase. J. Biol. Chem. published February 8, 2001 as 10.1074/jbc.M009331200. 

However it was later shown that fumonisin B1 treatment does not impair receptor- or dmg-induced apoptosis (Jaffrezou et al 1996), strenghtening the notion that sphingomyelin breakdown plays the major part in the generation of the biologically relevant ceramide. 

Major chemical contaminants implicated in food safety include pesticides, herbicides, myeotoxins and antibiotics. These analytes have been targeted by numerous groups developing SPR biosensors. As these analytes are rather small (typical molecular weight < 1,000), inhibition assay has been a preferred detection format. Examples of chemical contaminants detected by SPR biosensors include pesticides atrazine and simazine (detection limits 0.05 ng/ml and 0.1 ng/ml respectively), mycotoxin Fumonisin B1 (detection limit 50 ng/ml ), and antibiotics Sulphamethazine, Sulphadiazine (detection limits 1 ng/ml and 20 ng/ml respectively). 

W. Mullett, P. C. Edward, and M. J. Yeung, "Immunoassay of Fumonisins by a Surface Plasmon Resonance Biosensor," Analytical Biochemistry 258, 161-167 (1998). 

A number of fusarium mycotoxins are produced, depending upon geographic origin. Among them are deoxynivalenol, zearalenone, fumonisins, and T-2 toxin. 

Figure 9.3 Chemical structures of (a) thichothecenes (including deoxynivalenol and T-2 toxin), (b) zearalenone, and (c) fumonisin BL...

Solutions containing more than 10 mol fumonisin are proven to effect negatively the production of amylase and elongation of radicles in seeds (Doehlert et al., 1994). Fumonisin also causes shoot and root length to be decreased (Lamprecht et al., 1994). It is assumed that fumonisins other than fumonisin Bi and B2 are much less potent than fumonisin Bi (which is always prevalent). 

The temperature and pH level of alcohol fermentation are reported as having a limited effect on fumonisin content (Bothast et ah, 1992 Hlywka and Bullerman, 1999). 

Although other toxins, such as fumonisin Bj, are now considered carcinogenic, government regulation of these metabolites has not kept pace, however some governmental organizations do have advisory levels. 

In the case of fumonisin control, there is also a strong relationship between insect damage and fusarium ear rot. Corn genotypes containing the anti-insectant protein Bt had lower fumonisin content (Munkvold et al., 1997, 1999). 

Bothast, R.U. et al.. Fate of fumonisin B1 in naturally contaminated corn during ethanol fermentation, Appl. Env. Microbiol., 58, 233, 1992. 

Breitholtz, A. et al.. Plasma ochratoxin A levels in three Swedish populations surveyed using an ion-pair HPLC technique, Food Addit. Contam., 8, 183, 1991. Gastello, M.M., Sumner, S.S. and Bullerman, L.B., Stability of fumonisins in thermally processed com products, J. Food Prot., 61, 1030, 1998. 

Doehlert, D.C., Knutson, C.A. and Vesonder, R.E., Phytotoxic effects of fumonisin B, on maize seedling growth, Mycopathologia, 127, 117, 1994. 

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