Microbiological Quality of Various Medicinal Herbal Teas and Coffee Substitutes

Abstract

Various herbal teas including German chamomile, Chrysanthemum Vascufl ow herb tea, hop, jasmine and orange fl owers, sweet marjoram, spearmint and thyme leaves, and papaya-mint tea as well as coffee substitutes (Bambu instant Swiss, Teeccino chocolate-mint, and Teeccino Mediterranean Espresso) were analyzed for fungal contamination and the presence of aerobic mesophilic bacteria (APC). The results of this investigation showed that fungal counts reached levels as high as 5.8 × 10 5 colony forming units (cfu) per gram. German chamomile harbored the highest fungal contamination. The most common fungi found in herbal teas were Aspergillus niger, Penicillium spp., Eurotium rubrum, E. chevalieri, A. fl avus, Fusarium spp., Alternaria alternata, and yeasts. Among the coffee substitutes, only the chocolate-mint coffee was contaminated with low numbers (Ͻ1.0 × 10 3 cfu g −1 ) of E. rubrum, Ulocladium spp. and Phoma spp., and with yeasts (Ͻ100-6.8 × 10 3 cfu g −1 ). Aerobic mesophilic bacteria were recovered from 100% of the herbal tea, chocolate-mint and Mediterranean Espresso, and from 50% of the Bambu instant Swiss coffee samples. The highest APC counts of 1.2 × 10 7 cfu g −1 were observed in spearmint leaves.

Isolation of mycotoxins producing black aspergilli in herbal teas available on the Swiss market

“…Herbal teas were also found to be contaminated in variable amounts by other potentially toxigenic filamentous fungi including Penicillium and Fusarium. These observations are in agreement with previous literature, confirming black aspergilli as one of the most widespread group of molds in herbal teas (Halt, 1998;Tournas & Katsoudas, 2008). In total, 137 isolates representing eight species of the Aspergillus section Nigri could be recovered and identified by calmodulin sequencing.…”

“…Moreover, the presence of other potentially toxigenic fungi including members of the Aspergillus section Flavi, Penicillium and Fusarium had been observed here and reported also in other studies (Bugno et al, 2006;Tournas & Katsoudas, 2008). This indicates a potential risk of contamination with different major mycotoxins.…”

“…Different studies done in the past to assess the microbiological quality of herbal teas reported black aspergilli, and in particular A. niger, as one of the most frequently isolated group of filamentous fungi (Bugno, Almodovar, Pereira, Andreoli Pinto, & Sabino, 2006;Halt, 1998;Tournas & Katsoudas, 2008). However, species determination of molds collected in these works was based only on morphological observations.…”

Structural analysis of novel trehalose-based oligosaccharides from extremely stress-tolerant ascospores of Neosartorya fischeri (Aspergillus fischeri)

“…5e14 This is comparable to the resistance of spores of Bacillus subtilis and explains why Byssochlamys, Neosartorya and Talaromyces have caused a number of spoilage incidents after pasteurization. 15 Stabilization is a process in which biomolecules and complexes thereof are protected by these compatible solutes. They include polyols, sugars, betaines and amino acids, which are compatible with cellular functioning even at high concentration.…”

TEKİRDAĞ'DA SATIŞA SUNULAN IHLAMUR (Tilia spp.) ve KUŞBURNU (Rosa canina) ÖRNEKLERİNDE AFLATOKSİNLERİN VARLIĞININ ARAŞTIRILMASI

“…Atmosferde yayg›n olarak bulunmalar›ndan dolay› küfler, bitki çaylar›n›n da aralar›nda yer ald›¤› bitkisel materyalde en s›k karfl›lafl›lan kontaminantlar aras›nda yer almaktad›r. Bu türden bitkiler, aralar›nda toksijenik türlerin de yer ald›¤› küfleri yüksek düzeyde bar›nd›rabilmektedir (8,(11)(12)(13)(14). Toksijenik küflerin varl›¤› mikotoksin oluflumu riskini de beraberinde getirmektedir (15).…”