|PUGH, NIRMAL - University Of Mississippi|
|JACKSON, COLIN - University Of Mississippi|
|PASCO, DAVID - University Of Mississippi|
Submitted to: Planta Medica
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 10/8/2012
Publication Date: 10/29/2012
Citation: Pugh, N.D., Jackson, C.R., Pasco, D.S. 2012. Total bacterial load within Echinacea purpurea, determined using a new PCR-based quantification method, is correlated with LPS levels and In vitro macrophage activity. Planta Medica. 79:9-14.
Interpretive Summary: This is an original research paper on Echinacea, a popular dietary supplement that is used for immune support. The main finding of the article is that the activity (activation of immune cells) and content of lipopolysaccharide exhibited by extracts of the Echinacea is strongly correlated with total bacterial load of these plant samples. This manuscript also describes a new technique to assess total bacterial load within plants (both culturable and non-culturable bacteria). The results add to the growing body of evidence that bacteria within Echinacea are a major source of components responsible for enhancing innate immune function.
Technical Abstract: In the present study, total bacterial load was determined within E. purpurea samples and ranged from 6.4 × 106 to 3.3 × 108 bacteria/g of dry plant material. To estimate total bacterial load, we developed a PCR-based quantification method that circumvents the problems associated with nonviable/nonculturable cells (which precludes using plate counts) or the coamplification of mitochondrial or chloroplast DNA with the use of universal bacterial primers (which precludes the use of qPCR). Differences in total bacterial load within Echinacea samples were strongly correlated with the activity (NF-'B activation in THP-1 cells) and content of bacterial lipopolysaccharides within extracts of this plant material. These results add to the growing body of evidence that bacteria within Echinacea are the main source of components responsible for enhancing innate immune function.