Genotypic identification of Panicum spp. in New South Wales, Australia using DNA barcoding

Australia has over 30 Panicum spp. (panic grass) including several non-native species that cause crop and pasture loss and hepatogenous photosensitisation in livestock. It is critical to correctly identify them at the species level to facilitate the development of appropriate management strategies for efficacious control of Panicum grasses in crops, fallows and pastures. Currently, identification of Panicum spp. relies on morphological examination of the reproductive structures, but this approach is only useful for flowering specimens and requires significant taxonomic expertise. To overcome this limitation, we used multi-locus DNA barcoding for the identification of ten selected Panicum spp. found in Australia. With the exception of P. buncei, other native Australian Panicum were genetically separated at the species level and distinguished from non-native species. One nuclear (ITS) and two chloroplast regions (matK and trnL intron-trnF) were identified with varying facility for DNA barcode separation of the Panicum species. Concatenation of sequences from ITS, matK and trnL intron-trnF regions provided clear separation of eight regionally collected species, with a maximum intraspecific distance of 0.22% and minimum interspecific distance of 0.33%. Two of three non-native Panicum species exhibited a smaller genome size compared to native species evaluated, and we speculate that this may be associated with biological advantages impacting invasion of non-native Panicum species in novel locations. We conclude that multi-locus DNA barcoding, in combination with traditional taxonomic identification, provides an accurate and cost-effective adjunctive tool for further distinguishing Panicum spp. at the species level.

White Piedra: An Uncommon Superficial Fungal Infection of Hair

White piedra is a superficial fungal infection of hair caused by <i>Trichosporon</i> species. It presents clinically as white nodules encasing the hair shafts and may lead to increased fragility. It can usually be differentiated easily from clinically similar conditions based on clinical and microbiologic features. We report a case of white piedra of scalp hair in a 32-year-old female caused by <i>T. ovoides</i>, diagnosed using clinical, trichoscopic, microbiologic and molecular methods. In this case, trichoscopy acted as an interface between clinical and microbiologic examination, obviating the need for hair shaft microscopy. The genus <i>Trichosporon</i> contains 6 species of clinical significance viz., <i>T. asahii, T. asteroides, T. cutaneum, T. inkin, T. mucoides</i>, and <i>T. ovoides</i>, which cannot be differentiated based on their morphologic characteristics. A genotypic identification using molecular methods helped determine the causative species. It was treated successfully with oral itraconazole and topical ketoconazole.

Phenotypic and Genotypic Identification of Ureolytic Bacteria Isolated from Coastal Sites

Calcium Carbonate (CaCO3) is widespread compound in the aquatic and terrestrial environment, and used mainly as an ingredient in cement in the construction industry. Innovative ‘natural cement’ has been proposed as a green building material for use in many applications. Chemical cement has contains chemicals with environmentally detrimental effects, such as acids and sulphates. Thus, microbial Induced Calcite Precipitation (MICP) using urea hydrolysis applications has emerged as a promising process, due to its low cost, high quality, energy saving benefits, and environmentally protective properties. However, the limited understanding and low number of ureolytic bacterial strains impedes application. Therefore, this study examines several aspects of urease, employing ureolytic bacteria isolated from coastal soil from different locations in Jeddah, Saudi Arabia. Characterisation of the isolates, is described by growth pattern and next-generation sequencing of 16S rDNA. Ureolytic strains isolated are Staphylococcus sp., Bacillus sp., Brevibacillus sp, and Micrococcus luteus 2030. These strains show fundamentally different abilities for producing urease with rapid increases in pH. In this study, additional environmental bacteria were screened for their ability to produce urease, which is employed for (MICP) and provides further knowledge on the role of bacterial strains and their applications in the environmental fields.

Molecular Appreciation of the Native Bacterial Flora of Raw Milk in the North-Western Region of Algeria

Background: The appreciation of microbial milk communities, in order to promote useful flora and inhibit pathogenic one, has become one of the key factors in controlling the quality of cheeses.Methods: In this context, an approach to assess the bacterial flora of raw cow’s milk, was tested in 05 wilayas in north-western Algeria, on the one hand by a preliminary count of total flora and a phenotypic characterization based on morphological criteria and on the other hand by a genotypic identification of selected isolates, by the PCR method and sequencing of the gene encoding for the 16S ARNr.Result: The results of molecular analysis obtained from 72 isolates allowed the identification of 12 bacterial species with a dominance of the lactic microflora, 37% Lactococcus and 29% Enterococcus. This milk-native lactic microflora has become the main vector that preserves the distinctiveness of dairy products, including local cheese.

Contamination of Bovine Milk With Brucella spp.: A Current Public Health Menace in Kurdistan Province of Iran

Background: Brucellosis, a deteriorating zoonotic disease, is very common in most parts of Iran. Consumption of contaminated milk and dairy products is one of the most significant ways for transmission of the infections to human. Since the close rearing of cattle and sheep is practiced in Kurdistan province of Iran, the infection of cow with non-specific species is not out of mind. The present study aimed to determine the frequency of bovine milk contamination with zoonotic Brucella spp. Methods: A total of 240 milk samples, equally from traditional and industrialized dairy farms, were collected aseptically. Conventional microbiological method was used for isolation of the bacterium, followed by the genotypic identification of the isolates. Moreover, direct molecular processing of the samples was carried out for detection of the bacterial genome. The positive samples were further genotypically assessed to identify the contamination as Brucella abortus or Brucella melitensis. Results: In general, 16 (6.66%) and 15 (6.25%) of the samples were contaminated with Brucella spp. in phenotypic and genotypic methods, respectively. The proportion of contamination with B. abortus and B. melitensis in phenotypic and genotypic methods were 5% and 1.66%, and 5% and 1.25%, respectively. The overall rate of contamination in traditional milk samples was more than industrialized samples. Conclusions: Contamination of bovine milk with Brucella spp. is a serious threat to public health in the studied region. Continuous vaccination, application of test and slaughter policy, and presumption of pasteurized milk and dairy products are highly recommended.

Identification of a Lactococcus lactis Isolated from a Fresh Local Cheese of the Western Algerian Steppe “J’ben of Naama”

Background: The purpose of the study is to evaluate the diversity of lactococci, lactic bacteria, recovered from “J’ben”, a local cheese made from the milk of the Rembi sheep breed, a product of exploitation in the Algerian steppe regions of Naama.Methods: The bacterial species were isolated from samples of the recovered cheese exploitation and analyzed using genotypic methods. The isolation of bacterial DNA from purified Lactococcus cultures has been established by an amplification of ribosomal DNA 16s using the specific universal primers of prokaryotes. Result: The 16s DNA sequencing of all isolates, for genotypic identification, confirmed the predominance of Lactococcus lactis. This lactic dominance determines the quality and distinctiveness of this cheese in the region. The results obtained from acidification and proteolysis kinetics met the technological requirements and good functionality, from the strains used individually and in mixed culture to the cheese processing.

Activity of probiotics from food origin for oxalate degradation

There has been a concentrated attempt to introduce bacteria with oxalate degrading activity into the mammalian gut microbiota to enhance ecosystem function towards more effective oxalate degradation and prevent diseases. A few reports have studied Lactic acid bacteria (LAB) as promising intestinal oxalate degrading probiotic to treat kidney stone disease. In the present study, a total of 495 LAB isolates from different dairy products samples were primary characterized. Eighty-eight of the isolates belonged to genus Lactobacillus and were screened for their ability to degrade oxalate. Twenty-three of isolated lactobacilli showed oxalate degradation ability. According to the diameter of clear zone and the viable count, ten isolates were the most potent isolates for oxalate degradation. After the genotypic identification using 16s rDNA sequencing for these potent isolates, only seven strains were belonging to genus Lactobacillus spp. Lactobacillus fermentum (5 strains) and Lactobacillus gastricus (2 strains). These isolates were assessed for potential probiotic properties in vitro for further in vivo assessment. In conclusion, they exhibited good probiotic characters that suggested them to serve as good probiotic candidates for managing hyperoxaluria.