In Mexico, the farming of shrimp and other marine species represents an important activity that provides profits for producers, is a good source of food with high nutritional value, and gives a job opportunity for skilled and unskilled workers. Therefore, new strategies that improve biosafety protocols are necessary today, to ensure an adequate control of diseases that limit shrimp production. The implementation of non-antibiotic agents, such as probiotics, has emerged as a promising strategy to enhance shrimp farming.
The evaluation of its controlled and targeted release within a simulated shrimp digestive tract (DT). The encapsulation process was carried out using the ionic gelation technique. Both free and bacteria-loaded AMPs were physicochemically characterized by size, morphology, surface electrical charge, the survival, and the number of encapsulated bacteria after the encapsulation process, and the bacterial survival after 40-days of storage (at 4 ?C and 25 ?C). The in vitro release and survival studies of the bacteria were carried out using a protocol developed in our laboratory by implementing buffers of dissected organs from shrimp’s DT.
Results indicated that microparticles with an average size of 172–185 μm and negatively charged (- 16.77 and - 17.66 mV, respectively) were obtained after using the ionic gelation method (Fig. 1). The bacterial survival and encapsulation efficiency showed high cell viability and yield above 99%. Stability studies showed that the best storage temperature was 4 ?C, in which it remained almost 100% of the bacteria viable for 15 days; however, cell viability declined to 55% survival after 30 days of storage at this temperature.
Regardless of the cell viability reduction after 30 days, there are enough viable bacteria cells to be considered as a probiotic product. Release and survival studies showed that alginate particles had a protective effect on bacteria by keeping ca. 51.29% of viable probiotic within the shrimp intestine; in contrast, free bacteria only reached the shrimp intestine ca. 27.16% viable (Fig. 2).
Our results suggest that microparticles can be produced by a low-cost method that could ultimately benefit shrimp farming in a near future.