In vitro evaluation of the activity of microencapsulated carvacrol against Escherichia coli with K88 pili.
OBJECTIVE
The aim of the current study is to develop encapsulation of essential oils for oral delivery to the small intestine of pigs in order to retain their antimicrobial activity.


RESULTS
Carvacrol was used as a model essential oil and successfully encapsulated in microcapsules made from Ca-alginate hydrogel using an emulsion-extrusion technology with high encapsulation efficiency. This encapsulation method did not compromise the antimicrobial activity when tested against Escherichia coli K88 in a culture medium, as well as in a simulated gastrointestinal model. In the simulated gastrointestinal model, <20% of encapsulated carvacrol was released in the simulated gastric fluid; the rest was nearly completely released in the intestinal fluid after 6 h of incubation.


CONCLUSIONS
Encapsulation in Ca-alginate microcapsules could effectively reduce the early absorption of carvacrol in the upper gastrointestinal tract after oral administration, therefore, retains its potential antibacterial activity for the small intestine.


CONCLUSIONS
The developed encapsulation method is expected to be suitable for encapsulation of other essential oils. The results from this study would increase the likelihood of success in the application of essential oils as antimicrobial agents for controlling enteric diseases in pigs.
Wang
Q
Q
Guelph Food Research Center, Agriculture and Agri-Food Canada, Guelph, ON, Canada.
Gong
J
J
Huang
X
X
Yu
H
H
Xue
F
F
D000284:Administration, Oral; D000464:Alginates / Q000737:chemistry*; D000818:Animals; D000900:Anti-Bacterial Agents / Q000008:administration & dosage* / Q000737:chemistry; D000942:Antigens, Bacterial / Q000378:metabolism; D000081007:Cymenes; D004339:Drug Compounding; D004926:Escherichia coli / Q000187:drug effects*; D004927:Escherichia coli Infections / Q000517:prevention & control; D029968:Escherichia coli Proteins / Q000378:metabolism; D036781:Fimbriae Proteins / Q000378:metabolism; D020723:Glucuronic Acid / Q000737:chemistry; D006603:Hexuronic Acids / Q000737:chemistry; D007421:Intestine, Small / Q000382:microbiology; D039821:Monoterpenes / Q000008:administration & dosage* / Q000737:chemistry; D009822:Oils, Volatile / Q000008:administration & dosage* / Q000737:chemistry; D013552:Swine
D000464:Alginates; D000900:Anti-Bacterial Agents; D000942:Antigens, Bacterial; D000081007:Cymenes; D029968:Escherichia coli Proteins; D006603:Hexuronic Acids; C026888:K88 antigen, E coli; D039821:Monoterpenes; D009822:Oils, Volatile; D036781:Fimbriae Proteins; D020723:Glucuronic Acid; C073316:carvacrol