Stem Bromelain Proteolytic Machinery: Study of the Effects of its Components on Fibrin (ogen) and Blood Coagulation.

BACKGROUND: Antiplatelet, anticoagulant and fibrinolytic activities of stem bromelain (EC 3.4.22.4) are well described, but more studies are still required to clearly define its usefulness as an antithrombotic agent. Besides, although some effects of bromelain are linked to its proteolytic activity, few studies were performed taking into account this relationship. OBJECTIVE: We aimed at comparing the effects of stem bromelain total extract (ET) and of its major proteolytic compounds on fibrinogen, fibrin, and blood coagulation considering the proteolytic activity. METHODS: Proteolytic fractions chromatographically separated from ET (acidic bromelains, basic bromelains, and ananains) and their irreversibly inhibited counterparts were assayed. Effects on fibrinogen were electrophoretically and spectrophotometrically evaluated. Fibrinolytic activity was measured by the fibrin plate assay. The effect on blood coagulation was evaluated by the prothrombin time (PT) and activated partial thromboplastin time (APTT) tests. Effects were compared with those of thrombin and plasmin. RESULTS: Acidic bromelains and ananains showed thrombin-type activity and low fibrinolytic activity, with acidic bromelains being the least effective as anticoagulants and fibrinolytics; while basic bromelains, without thrombin-like activity, were the best anticoagulant and fibrinolytic proteases present in ET. Procoagulant action was detected for ET and its proteolytic compounds by the APTT test at low concentrations. The measured effects were dependent on proteolytic activity. CONCLUSION: Two sub-populations of cysteine proteases exhibiting different effects on fibrin (ogen) and blood coagulation are present in ET. Using well characterized stem bromelain regarding its proteolytic system is a prerequisite for a better understanding of the mechanisms underlying the bromelain action.

Proteolytic extracts of three Bromeliaceae species as eco-compatible tools for leather industry.

Most tanneries use high proportions of Na2S and CaO during the dehairing step, resulting in effluents of high alkalinity and large amounts of suspended solid, besides the risk of liberating the toxic H2S. Solid waste rich in protein is another environmental problem of tanneries. Enzymes are an interesting technological tool for industry due to their biodegradability, nontoxic nature, and nonpolluting effluent generation. In the leather industry, proteases have been chosen as a promising eco-friendly alternative to Na2S/CaO dehairing. Extracts with high proteolytic activity have been obtained from fruits of Bromeliaceae species: Bromelia balansae Mez (Bb), Bromelia hieronymi Mez (Bh), and Pseudananas macrodontes (Morr.) Harms (Pm). In this work, Bb, Bh, and Pm have been studied for application in the leather industry, focusing in their dehairing properties. Enzymatic activities were measured against collagen, keratin, elastin, and epidermis while a dehairing assay was performed by employing cowhide. All extracts showed similar activity on collagen and epidermis, while Bh and Pm were the most active against keratin at the same caseinolytic unit (CU) values; Bh was the only extract active against elastin. Bb (1 CU/ml), Bh (1.5 CU/ml), and Pm (0.5 CU/ml) were able to depilate cowhide. Desirable characteristics of dehairing were observed for all extracts since hair pores did not show residual hair, grain surface was clean and intact, and collagen fiber bundles of dermis were not damaged. In conclusion, results here presented show that proteolytic extracts of Bromeliaceae species are promising eco-compatible tools for leather industry.