Enkephalin related peptides are released from jejunum wall by orally ingested bromelain

Encapsulation of Bromelain in Combined Sodium Alginate and Amino Acid Carriers: Experimental Design of Simplex-Centroid Mixtures for Digestibility Evaluation

Bromelain has potential as an analgesic, an anti-inflammatory, and in cancer treatments. Despite its therapeutic effects, this protein undergoes denaturation when administered orally. Microencapsulation processes have shown potential in protein protection and as controlled release systems. Thus, this paper aimed to develop encapsulating systems using sodium alginate as a carrier material and positively charged amino acids as stabilizing agents for the controlled release of bromelain in in vitro tests. The systems were produced from the experimental design of centroid simplex mixtures. Characterizations were performed by FTIR showing that bromelain was encapsulated in all systems. XRD analyses showed that the systems are semi-crystalline solids and through SEM analysis the morphology of the formed systems followed a pattern of rough microparticles. The application of statistical analysis showed that the systems presented behavior that can be evaluated by quadratic and special cubic models, with a p-value < 0.05. The interaction between amino acids and bromelain/alginate was evaluated, and free bromelain showed a reduction of 74.0% in protein content and 23.6% in enzymatic activity at the end of gastric digestion. Furthermore, a reduction of 91.6% of protein content and 65.9% of enzymatic activity was observed at the end of intestinal digestion. The Lis system showed better interaction due to the increased stability of bromelain in terms of the amount of proteins (above 63% until the end of the intestinal phase) and the enzymatic activity of 89.3%. Thus, this study proposes the development of pH-controlled release systems aiming at increasing the stability and bioavailability of bromelain in intestinal systems.

High Retention and Purification of Bromelain Enzyme (Ananas comosus L. Merrill) from Pineapple Juice Using Plain and Hollow Polymeric Membranes Techniques

The demand for bromelian and pineapple fruit has been increasing substantially in the world because of their benefits for the human health and use in diverse areas. In this context, this work aimed to study the capacity of higher retention (concentration); bromelain activity underwent ultrafiltration from pineapple juice (Ananas comusus L. Merrill). All assays were carried out at pH 7.0 and 7.5, and at 0.05 and 0.40 bar of transmembrane pressures. Results have shown that at the best operating conditions, between 85 and 87% of bromelain activity was recovered using the plain membrane separation process at 0.05 bar. The ultrafiltration has shown the capacity to retain 100% of proteolytic activity of the bromelain extracted. The samples have kept the same physics properties after ultrafiltration, and the result was verified via electrophoresis. The bromelain enzyme obtained was characterized, and pH 7 and between 30 and 40 °C were the best conditions. Therefore, this work shows that the use of both polymeric membranes has shown high efficiency, and can be used in the purification of bromelain enzymes.

Structures of the free and inhibitors-bound forms of bromelain and ananain from Ananas comosus stem and in vitro study of their cytotoxicity

The Ananas comosus stem extract is a complex mixture containing various cysteine ​​proteases of the C1A subfamily, such as bromelain and ananain. This mixture used for centuries in Chinese medicine, has several potential therapeutic applications as anti-cancer, anti-inflammatory and ecchymosis degradation agent. In the present work we determined the structures of bromelain and ananain, both in their free forms and in complex with the inhibitors E64 and TLCK. These structures combined with protease-substrate complexes modeling clearly identified the Glu68 as responsible for the high discrimination of bromelain in favor of substrates with positively charged residues at P2, and unveil the reasons for its weak inhibition by cystatins and E64. Our results with purified and fully active bromelain, ananain and papain show a strong reduction of cell proliferation with MDA-MB231 and A2058 cancer cell lines at a concentration of about 1 μM, control experiments clearly emphasizing the need for proteolytic activity. In contrast, while bromelain and ananain had a strong effect on the proliferation of the OCI-LY19 and HL-60 non-adherent cell lines, papain, the archetypal member of the C1A subfamily, had none. This indicates that, in this case, sequence/structure identity beyond the active site of bromelain and ananain is more important than substrate specificity.