Extraction, Partial Purification and Characterization of Bromelain from Pineapple (Ananas Comosus) Crown, Core and Peel Waste

Abstract Ananas Comosus (also known as pineapple) is a part of Bromeliaceae family and it is consumed as food as well as folk medicine for the treatment of various diseases. It is reported that pineapple is a rich source of bromelain, a cysteine protease and it is considered as an important enzyme in different industries due to its significant therapeutic and industrial applications such as anticancer, anti-inflammatory and meat tenderizing. Bromelain is mostly present in fruit and stem of pineapple, but it is reported that crown, core, and peels, which constitute the waste of the pineapple plant, also contain bromelain but limited data is available. Therefore, the proposed study aimed at utilizing pineapple waste for the extraction and characterization of bromelain. Firstly, crude bromelain was extracted with phosphate buffer (pH 7), then it was subjected to partial purification using different fractions of ammonium sulphate (NH4)2SO4 such as 30, 40, 50 and 60% followed by desalting and concentration. Enzyme activity was calculated by using casein digesting unit (CDU) method. The results demonstrated that the crown bromelain showed highest purification of 4.34-fold at 30% (NH4)2SO4 saturation, whereas core and peel bromelain showed highest purification of 2.75 and 2.59-fold at 40% (NH4)2SO4 saturation. The molecular weight of crude and partially purified bromelain was determined by SDS-PAGE analysis and found to be 26 KDa. The pH and thermal stability of all the parts of pineapple showed maximum stability at pH 7 and at 35oC temperature.

N-(2-Hydroxyphenyl)acetamide: a Novel Suppressor of RANK/RANKL Pathway in Collagen-Induced Arthritis Model in Rats.

RANKL and RANK are potential contributors of inflammatory cascade in human and animal model of arthritis. The current study aims to investigate the effect of N-(2-hydroxyphenyl)acetamide (NA-2) on regulation of RANKL pathway in collagen-induced arthritis (CIA) model in rats. CIA was induced using bovine type II collagen in female Wistar rats. The clinical parameters, level of pro-inflammatory and oxidative stress markers were measured to determine the progression of the disease. The mRNA level of RANKL and RANK and downstream mediators of inflammation i.e. c-fos, c-jun, NF-κB and Akt were analysed in spleen tissue using real-time PCR. Immunohistochemical analysis of iNOS, pAkt and c-Fos was also done in spleen tissue. Treatment with NA-2 and indomethacin showed increase in body weight and significant reduction in paw volume and arthritic score (p < 0.0001). Marked reduction in the level of oxidative stress markers, NO, PO and GSH (p < 0.0001), and pro-inflammatory markers, IL-1ß (p < 0.0001) and TNF-α (p < 0.01), was also observed. Likewise, NA-2 and indomethacin treatment also significantly suppressed the mRNA expression of RANKL, RANK, c-fos, c-jun, NF-κB (p < 0.0001) and Akt (p < 0.01) and protein expression of iNOS, pAkt and c-Fos (p < 0.0001) compared to the arthritic control group. Our findings suggest that NA-2 is an antiarthritic agent acting in a pleiotropic manner in CIA rats by not only reducing the clinical signs of arthritis, inflammatory cytokines and free radical production but also attenuating the RANK/RANKL signaling pathway.