The potential of aerosol eDNA sampling for the characterisation of commercial seed lots

High-Resolution Melting Analysis Potential for Saccharomyces cerevisiae var. boulardii Authentication in Probiotic-Enriched Food Matrices

To date, the only probiotic yeast with evidence of health-promoting effects is Saccharomyces cerevisiae var. boulardii. The expanded market including dietary supplements and functional foods supplemented with Saccharomyces cerevisiae var. boulardii creates an environment conductive to food adulterations, necessitating rapid testing to verify product probiotic status. Herein, qPCR-HRM analysis was tested for probiotic yeast identification. The effectiveness of the primer pairs' set was examined, designed to amplify heterogeneous regions in (a) rDNA sequences previously designed to identify food-derived yeast and (b) genes associated with physiological and genotypic divergence of Saccharomyces cerevisiae var. boulardii. Preliminary tests of amplicons' differentiation power enabled the selection of interspecies sequences for 18SrRNA and ITS and genus-specific sequences HO, RPB2, HXT9 and MAL11. The multi-fragment qPCR-HRM analysis was sufficient for culture-dependent Saccharomyces cerevisiae var. boulardii identification and proved effective in the authentication of dietary supplements' probiotic composition. The identification of S. cerevisiae var. boulardii in complex microbial mixtures of kefir succeeded with more specific intragenus sequences HO and RPB2. The predominance of S. cerevisiae var. boulardii in the tested matrices, quantitatively corresponded to the probiotic-enriched food, was crucial for identification with qPCR-HRM analysis. Considering the reported assumptions, qPCR-HRM analysis is an appropriate tool for verifying probiotic-enriched food.

Macrobial airborne environmental DNA analysis: A review of progress, challenges, and recommendations for an emerging application

In the context of looming global biodiversity loss, effective species detection represents a critical concern for ecological research and management. Environmental DNA (eDNA) analysis, which refers to the collection and taxonomic identification of genetic fragments that are shed from an organism into its surroundings, emerged approximately 15 years ago as a sensitive tool for species detection. Today, one of the frontiers of eDNA research concerns the collection and analysis of genetic material in dust and other airborne materials, termed airborne eDNA analysis. As the study of airborne eDNA matures, it is an appropriate time to review the foundational and emerging studies that make up the current literature, and use the reviewed literature to summarize, synthesize, and forecast the major challenges and opportunities for this advancing research front. Specifically, we use the "ecology of eDNA" framework to organize our findings across the origin, state, transport, and fate of airborne genetic materials in the environment, and summarize what is so far known of their interactions with surrounding abiotic and biotic factors, including population and community ecologies and ecosystem processes. Within this work we identify key challenges, opportunities, and future directions associated with the application of airborne eDNA development. Lastly, we discuss the development of applications, partnerships, and messaging that promote development and growth of the field. Together, the broad potential of eDNA analysis and the rate at which research is accelerating in this field suggest that the sky's the limit for airborne eDNA science.

Applications of environmental DNA (eDNA) in agricultural systems: Current uses, limitations and future prospects

Global food production, food supply chains and food security are increasingly stressed by human population growth and loss of arable land, becoming more vulnerable to anthropogenic and environmental perturbations. Numerous mutualistic and antagonistic species are interconnected with the cultivation of crops and livestock and these can be challenging to identify on the large scales of food production systems. Accurate identifications to capture this diversity and rapid scalable monitoring are necessary to identify emerging threats (i.e. pests and pathogens), inform on ecosystem health (i.e. soil and pollinator diversity), and provide evidence for new management practices (i.e. fertiliser and pesticide applications). Increasingly, environmental DNA (eDNA) is providing rapid and accurate classifications for specific organisms and entire species assemblages in substrates ranging from soil to air. Here, we aim to discuss how eDNA is being used for monitoring of agricultural ecosystems, what current limitations exist, and how these could be managed to expand applications into the future. In a systematic review we identify that eDNA-based monitoring in food production systems accounts for only 4 % of all eDNA studies. We found that the majority of these eDNA studies target soil and plant substrates (60 %), predominantly to identify microbes and insects (60 %) and are biased towards Europe (42 %). While eDNA-based monitoring studies are uncommon in many of the world's food production systems, the trend is most pronounced in emerging economies often where food security is most at risk. We suggest that the biggest limitations to eDNA for agriculture are false negatives resulting from DNA degradation and assay biases, as well as incomplete databases and the interpretation of abundance data. These require in silico, in vitro, and in vivo approaches to carefully design, test and apply eDNA monitoring for reliable and accurate taxonomic identifications. We explore future opportunities for eDNA research which could further develop this useful tool for food production system monitoring in both emerging and developed economies, hopefully improving monitoring, and ultimately food security.