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ABSTRACTWhile phylogenetic and cluster analyses are often used to define clonal groups within bacterial species, the identification of clonal groups that are associated with specific ecological niches or host species remains a challenge. We used Listeria monocytogenes, which causes invasive disease in humans and different animal species and which can be isolated from a number of environments including food, as a model organism to develop and implement a two-step statistical approach to the identification of phylogenetic clades that are significantly associated with different source populations, including humans, animals, and food. If the null hypothesis that the genetic distances for isolates within and between source populations are identical can be rejected (SourceCluster test), then particular clades in the phylogenetic tree with significant overrepresentation of sequences from a given source population are identified (TreeStats test). Analysis of sequence data for 120 L. monocytogenesisolates revealed evidence of clustering between isolates from the same source, based on the phylogenies inferred from actAand inlA(P= 0.02 and P= 0.07, respectively; SourceCluster test). Overall, the TreeStats test identified 10 clades with significant (P< 0.05) or marginally significant (P< 0.10) associations with defined sources, including human-, animal-, and food-associated clusters. Epidemiological and virulence phenotype data supported the fact that the source-associated clonal groups identified here are biologically valid. Overall, our data show that (i) the SourceCluster and TreeStats tests can identify biologically meaningful source-associated phylogenetic clusters and (ii) L. monocytogenesincludes clonal groups that have adapted to infect specific host species or colonize nonhost environments.

This investigation was designed to through light on the microbial status of some powdered herbal materials used in Triphala preparation. A total of 68 powdered samples Emblica officinalis (Amla), Terminalia belerica (Baheda) and Terminalia chebula (Harada) were collected from random sources in Gwalior market. Mycological analysis of powdered samples was carried out for the detection and enumeration of fungi using standard media. Samples were also investigated from mycotoxilogical point of view to identify mycotoxins associated. Fungal contamination was found in almost 91% of the samples. Aspergillus and Penicillium genera were detected more frequently than other genera i.e. Helminthosporium, Curvularia, Geotrichum, Fusarium, Rhizopus, Paecilomyces. In total, 771 fungal isolates belonging to 14 fungal species and 8 different genera were recorded. Overall, six species of genus Aspergillus and three of genus Penicillium were dominant. In spite of this natural infection of powder samples, only 14 (20.58%) out of 68 samples analyzed were found to be positive for mycotoxins including aflatoxins (B1, B2, G1 and G2), citrinin and sterigmatocystin. Therefore, study concluded that, as herbal drugs seems to be high risk products, thus require designing some more appropriate methods of their decontamination. Keywords: fungal contamination | powdered herbal drugs | storage | mycotoxins, Introduction The use of Ayurveda is one of the oldest, richest and most diverse traditions, associated with the use of medicinal plants in India (Tandon et al., 2004). In this [...]

The levels of fungal contamination were analyzed in 44 stored dried fruit samples of Emblica officinalis (Alma), Terminalia bellirica (Baheda) and Treminalia chebula (Haritiki), randomly collected from various retailers from Gwalior city (India). As a result of mycological examination, 97.77% of the total samples examined, found to be contaminated with different fungi. A total of 12 different fungal species were isolated from all the three types of fruit samples of Emblica officinalis, Terminalia bellirica and Terminalia chebula. The predominant mycoflora obtained was distributed in five different genera comprised of Aspergillus, Penicillium, Alternaria, Rhizopus and Syncephalastrum. The Aspergillus (71.95%) was observed as the most dominant genera recovered followed by Penicillium (15.44%), Rhizopus (9.51%), Alternaria (1.67%) and Syncephalastrum(1.41%). Most of the identified fungal species like Aspergillus, Penicillium and Alternaria are reported to have ability to produce mycotoxins like aflatoxins, ochratoxins, citrinine and alternaria toxins. The presence of a wide range of storage fungi indicates that the mould probably infects the crude herbal drugs during harvesting and post harvesting processing i.e. mainly during drying, storing, transportation and processing. On the basis of present investigations, it may be concluded that the contamination of raw materials is alarming, as these raw materials needs thorough inspection before being channeled to the drug industries and for public use. Keywords: Fruit samples | storage | fungal contamination | mycotoxins, Introduction Since ancient time herbal drugs--also known as phytomedicnes, are used in the prevention, treatment and cure of health disorders and diseases. In Ayruveda different parts of the medicinal plants [...]