Macrocyclic trichothecene toxins produced by Stachybotrys atra strains isolated in Middle Europe

Abstract

A total of 17 strains of Stachybotrys atra isolated in Hungary and Czechoslovakia were cultured on Sabouraud agar, and the toxins produced by them were chemically analyzed by gas-liquid chromatography, high-pressure liquid chromatography, and mass spectroscopy. Furthermore, brine shrimp (Artemia salina) bioassay was used for the determination of toxicity of the compounds examined. Macrocyclic trichothecenes (satratoxins H and G, roridin E, and verrucarin J as well as two other unidentified macrocyclic trichothecenes) were found in all of the cultures tested. The identities of satrotoxins H and G, roridin E, and verrucarin J were qualitatively determined by high-pressure liquid chromatography and gas-liquid chromatography. The ratio of satratoxins H and G and roridin E was found to be similar in each of the strains tested, but the amount of verrucarin J found was different in each of them. One of the unidentified macrocyclic trichothecenes was equivalent to the compound isolated by Harrach et al. (Harrach et al., Appl. Environ. Microbiol. 41:1428-1433, 1981). The other one proved to be a newly isolated macrocyclic trichothecene toxin. Stachybotryotoxicosis, one of the oldest mycotoxicoses known, and a serious problem in Middle Europe (Gy. Danko, Magy. Allatorv. Lapja 31:226-232, 1976), is believed to be caused by macrocyclic trichothecene toxins produced by Stachybotrys atra (R.M. Eppley, in Rodricks et al., ed., Mycotoxins in Human and Animal Health, p. 285-293, 1977). Forty years ago, the death of animals in the Soviet Union was associated with this fungus (C.U. Ruhliada, in Proceedings of the All-Union Sci. and Tech. Conf., p. 47-51, 1980). Today, these strains cause considerable damage in Hungary and other European countries (Gy. Danko, Magy. Allatorv. Lapja 27:241-249, 1972; Gy. Danko, Magy. Allatorv. Lapja 31:226-232, 1976; E.L. Hintikka, in Rodricks et al., ed., Mycotoxins in Human and Animal Health, p. 277-284, 1977; LeBars et al. Ann. Nutr. Aliment. 31:509-517, 1977; Palyusik et al., Magy. Allatorv. Lapja 26:304-306, 1971; Szabo et al., Magy. Allatorv. Lapja 25:21-27, 1970) and in the Republic of South Africa (Schneider et al., J. S. Afr. Vet. Assoc. 50:73-81, 1979). Stachybotryotoxicosis has been diagnosed in horses (Ruhliada, 1980), calves (Danko, 1972), sheep (Danko, 1976; Schneide et al., 1979), swine (Szabo et al., 1970), ruminants in zoological gardens (LeBars et al., 1977), and in humans (Andrassy et al., Mycosen 23:130-133, 1980; Szabo et al., 1970). Stachybotrys toxins were thought initially to be steroids (V.G. Drobotko, in Fungus Disease of Horses and People, 1949), and accordingly, the resorcinol test was used for their detection (R.U. Yuskiv, Mikrobiol. J. [Kiev] 30:68-71, 1968). However, this assumption was not correct, and resorcinol-negative Stachybotrys toxins were described (Danko, 1976; M. Nummi and M.L. Niku-Paavola, Ann. Nutr. Aliment. 31:761-770, 1977; S.V. Pathre, C.J. Mirocha, and M. Palyusik, Abstr. 2nd Int. Congr. Plant Pathol., Am. Phytopathol. Soc., St. Paul, Minn., abstr. no. 978, 1973). On the basis of clinical signs and autopsy findings of stachybotryotoxicosis, it was then presumed that Stachybotrys toxins, like the Fusarium toxins possessing similar cytotoxic effects, were trichothecene mycotoxins (J.R. Bamburg and F.M. Strong, in Kadis et al., ed., Microbial Toxins, p. 209-292, 1972).