Herbal hydrogel-based encapsulated Enterococcus faecium ABRIINW.N7 improves the resistance of red hybrid tilapia against Streptococcus iniae.

AIMS: The streptococcal disease has been associated with serious mortality and significant global economic loss in the tilapia farming industry. The overall goal of this work was to test herbal hydrogels based on encapsulated Enterococcus faecium ABRIINW.N7 for potential probiotic anti-microbial activity against Streptococcus iniae in red hybrid tilapia. METHODS AND RESULTS: Abnormal behaviour, clinical signs, postinjection survival and histopathology (kidney, liver, eye and brain) were measured. Cumulative mortality of CON+ , free cells, ALG and treatments (F1-F7) was 30, 24, 22, 19, 17, 17, 16, 14, 14 and 12 out of 30 fish and the survival rates for E. faecium ABRIINW.N7 microencapsulated in an alginate-BS blend with 0·5, 1, 1·5, 2, 2·5 and 3% fenugreek were 43, 43, 47, 53, 53 and 60%, respectively. After the incorporation of fenugreek with the alginate-BS blend, there was an 8-21% increase in probiotic cell viability. Furthermore, the survival rate for the alginate-BS blend with 2·5 and 3% fenugreek (F6 and F7) was significantly (P ≤ 0·05) higher than other blends. The highest encapsulation efficiency, viability in gastrointestinal conditions and during storage time and excellent antipathogenicity against S. iniae were observed in alginate-BS +3% fenugreek formulation (F7). CONCLUSIONS: It is recommended that probiotic strains like E. faecium ABRIINW.N7 in combination with local herbal gums, such as BS and fenugreek plus alginate, can be used as a suitable scaffold and an ideal matrix for the encapsulation of probiotics. SIGNIFICANCE AND IMPACT OF THE STUDY: This study proposes models connecting process parameters, matrix structure and functionality.

Microencapsulation of probiotic bacteria Lactobacillus plantarum 15HN using alginate-psyllium-fenugreek polymeric blends.

AIMS: Investigation on the use of herbal-based biopolymers for probiotic-Lactobacillus plantarum 15HN-encapsulation is presented. The objectives are to enhance its oral delivery, colonic release and survival rate of these probiotic cultures in gastrointestinal environment. METHODS AND RESULTS: Nine types of herbal-based polymers blend with different concentration of alginate alone or mixed with psyllium and fenugreek was used as candidate for encapsulation matrix by applying a simple extrusion method. All the blend formulations recorded high encapsulation efficiency at value >98%. The survival rate of viable probiotic cells under both low pH and high bile salt conditions was also high with value above 80% in 2% (w/v) alginate, alginate+psyllium (1·5 + 0·5%) blend and alginate+fenugreek (1·5 + 0·5%) blend as compared to other polymer formulations and nonencapsulated cells. Their release occurred after 2 h in colonic condition and sustained until the 12th hour incubation period. A value added prebiotic effect was observed in (1·5 + 0·5%) alginate-psyllium formulation. CONCLUSIONS: The high encapsulation efficiency, high viability of cell in low pH, high bile salt and the sustained release rates of probiotic cells in colonic condition during storage time was also observed for these herbal gel formulations. SIGNIFICANCE AND IMPACT OF THE STUDY: Herbal-based biopolymers offer added advantages of being prebiotic towards the enhancement of probiotic bacterial growth in the gastrointestinal environment.