High levels of glycoalkaloids in the established swedish potato variety magnum bonum

Abstract

In 1986, potentially toxic levels of the glycoalkaloids a-solanine and a-chaconine were unexpectedly found in tubers of the established Swedish consumer potato variety Magnum Bonum, leading to the imposition of a conditional sales ban on such potatoes. The combined amounts of a-solanine and a-chaconine in more than 300 commercial lots of Magnum Bonum potatoes analysed as a consequence of the ban ranged from 61 to 665 mg kg-' fresh weight with an average of 254 mg kg-'. Sixty-six percent of the samples exceeded a temporary maximum residue limit of 200 mg kg-', 8% were above 400 mg kg-'. Peeling did not significantly remove the glycoalkaloids in tubers with a high content. The occasional glycoalkaloid elevation was initially attributed to the unusually cold and rainy conditions during the late part of the season in 1986, but subsequent investigations have failed to confirm this hypothesis. Varietal characteristics are likely to have been involved since most other common Swedish varieties seemed to have had normal glycoalkaloid levels in 1986. There were no indications of serious or widespread adverse health effects in consumers due to the high glycoalkaloid levels, although there was circumstantial evidence that a few cases of temporary gastrointestinal disturbances were caused by consumption of Magnum Bonum potatoes with glycoalkaloid concentrations in the range 310-1000 mg kg-'.

Effect of environmental stress during tuber development on accumulation of glycoalkaloids in potato (Solanum tuberosum L)

“…The glycoalkaloid results for British Queen observed here are consistent with those of Hellena Ès et al, 12 who found higher than normal glycoalkaloid levels in tubers of cvs British Queen and Magnum Bonum grown as commercial crops in Sweden in 1986. The authors correlated their results with the abnormally wet and cold conditions close to harvest and stated that the Table 2 combination of cold weather and heavy precipitation might be important rather than each individual stress.…”

Effect of cultivar, flesh colour, location and year of cultivation on the glycoalkaloid content in potato tubers

“…This finding is contrary to the findings of Zrůst et al (2000), who reported high levels of TGA during the dry, warm sunshine and rich growing season. Explanation, however, can offer a hypothesis of the authors Hellenäs et al (1995), which was published in connection with excluding Swedish cv. Magnum Bonum from the market because toxic levels of TGA were found in it (the contents of more than 300 analysed commercial samples reached average values of 254 mg TGA/kg FM).…”

Light-induced glycoalkaloid accumulation of potato tubers (Solanum tuberosum L)

“…Such a response is now well established and has been reported by workers elsewhere. 11,13,15,16 Cultivar Kestrel proved the most light-sensitive genotype, and cv Maris Piper relatively light-insensitive. Initial glycoalkaloid concentrations in both cultivars were similar at 71.5 and 95.2 mg kg À1 FW respectively, but rates of accumulation thereafter differed markedly (Table 2).…”

“…Glycoalkaloids were extracted from each individual tuber as described in Ref 15, and quanti®ed using high-pressure liquid chromatography. 16 …”