Isolation and PCR Detection of Foreign DNA Sequences in Bee Honey Raised on Genetically Modified Bt (Cry 1 Ac) Cotton

Pollen from genetically modified plants in honey – problems with quantification and proper labelling

“…This task is challenging because honey contains very small amounts of pollen (Sawyer, 1988). Centrifugation (according to German Standard DIN 10760) or filtration (not standardized) methods are generally used for the isolation of pollen from honey (Cheng et al, 2007;European Union Reference Laboratory, 2012). The number of pollen grains from an individual plant species that are present in honey determines the amount of extractable DNA for that species.…”

“…After extraction, it is not possible to separate pollen DNA from the total DNA. In addition, honey contains up to 83% sugars that can hinder DNA extraction, so the separation of sugars from DNA is crucial (Cheng et al, 2007). The acidity (pH value of approximately 3.9) and high viscosity (2 -10 N·s/m 2 ) of honey also complicate DNA extraction.…”

“…The limit of quantification was estimated at the level of 0.1% (w/w). Cheng et al (2007) described the DNA extraction procedure from honey and a PCR protocol for the detection of Bt cotton DNA sequences by a qualitative PCR test. Efficient DNA extraction from honey is not only necessary for GMO identification but also for the detection of plant species and pathogens (Dobbelaere et al, 2001;Piccini et al, 2002;Olivieri et al, 2012).…”

Protocol for Optimal Quality and Quantity Pollen DNA Isolation from Honey Samples

“…5 The fact that DNA from the plant(s) may be present in honey represents a useful, analytical tool to identify the host plants. 6 The haploid microspores of seed plants (the pollen) are the male part in sexual reproduction of flowers. Pollen grains have a very hard outer shell, called the exine, which is tough and can be found in fossil deposits, millions of years old.…”

“…The present study aims to develop a simple and efficient method for the extraction of PCR amplifiable chloroplast DNA (cpDNA) with a reduced sample amount of 3 ml honey compared with previous studies (e.g., 10 ml by Cheng et al 6 and 10 g by Laube et al 7 ). As other honey DNA isolation methods are mostly described as kit-based approaches, we developed an easy and efficient method for honey DNA isolation by conventional phenol-chloroform methods.…”