Publications (121) View all
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Article: The biodiversity of Aspergillus section Flavi in brazil nuts: From rainforest to consumer.
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ABSTRACT: A total of 288 brazil nut samples (173 kernel and 115 shell) from the Amazon rainforest region and São Paulo State, Brazil were collected at different stages of brazil nut production. Samples were analysed for: percentages of aflatoxigenic fungal species and potential for aflatoxin production and presence of aflatoxins. Aspergillusnomius was the most common species found (1235 isolates) which amounted to 30% of the total species with potential to produce aflatoxins. This species is of concern since 100% of all isolates produced aflatoxins B(1), B(2), G(1) and G(2). Aspergillusflavus was almost equally common (1212 isolates) although only 46% produced aflatoxins under laboratory conditions, and only aflatoxins B(1) and B(2). Low number of other species with the potential to produce aflatoxins was isolated: Aspergillusarachidicola and Aspergillus bombycis produced B and G aflatoxins whilst Aspergilluspseudotamarii produced only aflatoxin B(1). The total aflatoxin levels found in samples taken from the rainforests was 0.7μg/kg, from processing plants before and after sorting 8.0 and 0.1μg/kg respectively, from street markets in the Amazon region 6.3μg/kg and from supermarkets in São Paulo State 0.2μg/kg. Processing, which included manual or mechanical sorting and drying at 60°C for 30 to 36h, eliminated on average more than 98% of total aflatoxins. These results showed that sorting is a very effective way to decrease aflatoxin content in brazil nuts.International journal of food microbiology 01/2013; 160(3):267-72. · 3.01 Impact Factor -
Article: Two new Penicillium species P. buchwaldii and P. spathulatum, producing the anticancer compound asperphenamate.
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ABSTRACT: Penicillium buchwaldii sp. nov. (type strain CBS 117181(T) = IBT 6005(T) = IMI 30428(T) ) and Penicillium spathulatum sp. nov. (CBS 117192(T) = IBT 22220(T) ) are described as new species based on a polyphasic taxonomic approach. Isolates of P. buchwaldii typically have terverticillate conidiophores with echinulate thick walled conidia and produce the extrolites asperphenamate, citreoisocoumarin, communesin A and B, asperentin and 5'-hydroxy-asperentin. Penicillium spathulatum is unique in having restricted colonies on Czapek yeast agar (CYA) with an olive grey reverse, good growth on CYA supplemented with 5% NaCl, terverticillate bi- and ter-ramulate conidiophores and consistently produces the extrolites benzomalvin A and D, and asperphenamate. The two new species belong to Penicillium section Brevicompacta and are phylogenetically closely related to Penicillium tularense. With exception of P. fennelliae, asperphenamate is also produced by all other species in section Brevicompacta (P. tularense, P. brevicompactum, P. bialowiezense, P. olsonii, P. astrolabium and P. neocrassum). Both new species have a worldwide distribution. The new species were mainly isolated from indoor environments and food and feedstuffs. The fact that asperphenamate has been found in many widely different plants may indicate that endophytic fungi rather than the plants are the actual producers. © 2012 Federation of European Microbiological Societies. Published by Blackwell Publishing Ltd. All rights reserved.FEMS Microbiology Letters 11/2012; · 2.04 Impact Factor -
Article: Taxonomy of Penicillium citrinum and related species
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ABSTRACT: Penicillium citrinum and related species have been examined using a combination of partial β-tubulin, calmodulin and ITS sequence data, extrolite patterns and phenotypic characters. It is concluded that seven species belong to the series Citrina. Penicillium sizovae and Penicillium steckii are related to P. citrinum, P. gorlenkoanum is revived, Penicillium hetheringtonii sp. nov. and Penicillium tropicoides sp. nov. are described here as new species, and the combination Penicillium tropicum is proposed. Penicillium hetheringtonii is closely related to P. citrinum and differs in having slightly broader stipes, metulae in verticils of four or more and the production of an uncharacterized metabolite, tentatively named PR1-x. Penicillium tropicoides resembles P. tropicum, but differs in the slow maturation of the cleistothecia, slower growth at 30°C and the production of isochromantoxins. The type strain of P. hetheringtonii is CBS 122392T (=IBT 29057T) and the type strain of P. tropicoides is CBS 122410T (=IBT 29043T). Keywords Penicillium -Citrinin- Steckii - Sizovae - Citrinum -Taxonomy-Series CitrinaFungal diversity 04/2012; 44(1):117-133. · 4.77 Impact Factor -
Article: Chemical characterisation of cheese associated fungi
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ABSTRACT: Recent work in our laboratory has demonstrated that the most common contaminating fungi on different types of cheese are;Penicillium commune, P. nalgiovense, P. solitum, P. discolor, P. roqueforti, P. crustosum, P. nordicum andAspergillus versicolor. On blue cheese a new speciesP. caseifulvum has been discovered as a surface contaminant. A large number of known and unknown metabolites have been described from the above mentioned cheese associated fungi from both synthetic media and real samples. Based on chemotaxonomy our laboratory has discovered thatP. roqueforti should be divided into three species:P. roqueforti (from cheese),P. carneum (from meat) andP. paneum (from bread). SimilarlyP. verrucosum should be divided intoP. verrucosum (from cereals) andP. nordicum (from cheese and meat products). Both species produce ochratoxins, however, only the former species produce citrinin. Unsere jüngsten Arbeiten zeigten, dass hauptsächlichPenicillium commune, P. nalgiovense, P. solitum, P. discolor, P. roqueforti, P. crustosum, P. nordicum undAspergillus versicolor verschiedene Käsesorten kontaminieren. Eine neue Art,P. caseifulvum, wurde jetzt als Oberflächenkontamination entdeckt. Eine Vielzahl bekannter und unbekannter Stoffwechselprodukte wurden sowohl in synthetischem Medium als auch in Käseproben gefunden. Basierend auf taxonomischen Untersuchungen fand unser Labor heraus, dassP. roqueforti in drei Arten unterteilt werden sollte:P. roqueforti (Käse),P. carneum (Fleisch) andP. paneum (Brot). Gleichermassen sollteP. verrucosum inP. verrucosum (Getreide) und inP. nordicum (Käse- und Fleischprodukte) unterteilt werden. Beide Arten produzieren Ochratoxine. Allerdings wird Citrinin nur vonP. verrucosum produziert.Mycotoxin Research 04/2012; 16:109-112. -
Article: Food fermentations: microorganisms with technological beneficial use.
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ABSTRACT: Microbial food cultures have directly or indirectly come under various regulatory frameworks in the course of the last decades. Several of those regulatory frameworks put emphasis on "the history of use", "traditional food", or "general recognition of safety". Authoritative lists of microorganisms with a documented use in food have therefore come into high demand. One such list was published in 2002 as a result of a joint project between the International Dairy Federation (IDF) and the European Food and Feed Cultures Association (EFFCA). The "2002 IDF inventory" has become a de facto reference for food cultures in practical use. However, as the focus mainly was on commercially available dairy cultures, there was an unmet need for a list with a wider scope. We present an updated inventory of microorganisms used in food fermentations covering a wide range of food matrices (dairy, meat, fish, vegetables, legumes, cereals, beverages, and vinegar). We have also reviewed and updated the taxonomy of the microorganisms used in food fermentations in order to bring the taxonomy in agreement with the current standing in nomenclature.International journal of food microbiology 03/2012; 154(3):87-97. · 3.01 Impact Factor
