Strategies for achieving global food security include identification of alternative feedstock for use as animal feed, to contribute towards efforts at increasing livestock farming. The presence of theobromine in cocoa pod husks, a major agro-waste in cocoa-producing countries, hinders its utilisation for this purpose. Cheap treatment of cocoa pod husks to remove theobromine would allow largescale beneficial use of the millions of metric tonnes generated annually. The aim of this study was to isolate theobromine-degrading filamentous fungi that could serve as bioremediation agents for detheobromination of cocoa pod husks. Filamentous fungi were screened for ability to degrade theobromine. The most promising isolates were characterized with respect to optimal environmental conditions for theobromine degradation. Secretion of theobromine-degrading enzymes by the isolates was investigated. Theobromine degradation was monitored by HPLC. Of fourteen theobromine-degrading isolates collected and identified by rDNA 5.8S and ITS sequences, seven belonged to Aspergillus spp. and six were Talaromyces spp. Based on the extent of theobromine utilization, four isolates; Aspergillus niger, Talaromyces verruculosus and two Talaromyces marneffei, showed the best potential for use as bioagents for detheobromination. First-time evidence was found of the use of xanthine oxidase and theobromine oxidase in degradation of a methylxanthine by fungal isolates. Metabolism of theobromine involved initial demethylation at position 7 to form 3-methylxanthine, or initial oxidation at position 8 to form 3,7-dimethyuric acid. All four isolates degraded theobromine beyond uric acid. The data suggest that the four isolates can be applied to substrates, such as cocoa pod husks, for elimination of theobromine.

实现全球粮食安全的战略包括确定用作动物饲料的替代原料，以促进增加畜牧业的努力。可可豆壳中可可碱的存在是可可生产国的主要农业废物，可可豆壳中可可碱的存在阻碍了可可碱的利用。廉价处理可可豆荚以去除可可碱将使每年产生的数百万公吨的大规模有益利用成为可能。这项研究的目的是分离可可可碱降解的丝状真菌，其可作为可可豆荚皮脱可溴化的生物修复剂。筛选丝状真菌降解可可碱的能力。关于可可碱降解的最佳环境条件，对最有希望的分离物进行了表征。研究了分离物分泌可可碱降解酶的情况。通过HPLC监测可可碱的降解。通过rDNA 5.8S和ITS序列收集和鉴定的14种可可碱降解菌株中，有7种属于曲霉属 和六个是Talaromyces spp。根据可可碱利用的程度，分为四个分离株。黑曲霉，疣状Talaromyces verruculosus和两个Marineffei Talaromyces marneffei，显示出用作脱溴代生物试剂的最佳潜力。首次发现了黄嘌呤氧化酶和可可碱氧化酶在真菌分离物降解甲基黄嘌呤中的用途。可可碱的代谢涉及在位置7初始脱甲基以形成3-甲基黄嘌呤，或在位置8初始氧化以形成3,7-二甲基尿酸。所有四个分离株都降解了可可碱，而不是尿酸。数据表明，可以将四种分离物应用于可可豆荚等基质，以消除可可碱。