Microencapsulation of Antibiotic Alternatives Using Natural Polymers for the Target Location Delivery to Enhance Poultry Performance

Haona Bao, Tennessee State University


The combination of bioactive compounds essential oils (EOs) thymol and carvacrol with polyphenols (PP) from grape pomace extracts (GPE) has the synergistic antimicrobial effect thus can be used as natural antibiotic alternatives. This study was designed to optimize the microencapsulation formula of these bioactive compounds for a target location delivery system to modulate the microflora at the lower section of poultry intestinal tract and further enhance the growth performance. EOs and PP were encapsulated in natural polymers water-soluble yellow mustard mucilage (WSM), maltodextrin (MD) and gum Arabic (GA) at different ratios by spray drying. Before subjecting into the spray dryer, the optimized emulsions were prepared and evaluated for viscosities, flow behaviors, emulsion stabilities and droplet sizes. The fabricated microparticles were assessed in terms of encapsulation efficiency, particle size and morphology, molecular interaction between matrix materials and matrix with core materials and releasing profile using a simulated poultry gastric and intestinal digestion system. Further, the encapsulated particles were tested by in vivo study. In the poultry experiment, a total of 180 chicks were randomly divided into 4 treatment diets: control basal (CON), antibiotics (BAC, 250 ppm bacitracin), microparticle Dose A (DA, 300 ppm encapsulates), microparticle Dose B (DB, 600 ppm encapsulates), with a 42-day period feeding procedure. The intestinal microflora of boilers was determined using the 16S metagenomic sequencing test. The poultry performance was evaluated by collecting average body weight gain, average feed intake, and feed conversion ratio. Overall, the study showed that EOs and PP were most successfully encapsulated in WSM-MD-GA at ratio of 2/2/5 (w/w/w) and core to wall ratio of 1:5 using spray drying, with an average particle size 3.11 μm and less dent spherical particles, increased encapsulation efficiency (91%) and controlled release of EOs and PP under the stimulated acidic gastro digestion where 72.7% of active compounds were delivery to the lower section of intestinal tract. What’s more, the microparticles as feed additives significantly increased the growth performance of poultry with improved feed conversion rate (1.6). Our results proved the potential of encapsulated EOs and PP with WSM-MD-GA as an antibiotic alternative for the poultry production.

Subject Area

Agricultural engineering

Recommended Citation

Haona Bao, "Microencapsulation of Antibiotic Alternatives Using Natural Polymers for the Target Location Delivery to Enhance Poultry Performance" (2021). ETD Collection for Tennessee State University. Paper AAI28772363.