Characterization and Potential Application of Bromelain from Pineapple (Ananas comosus) Waste (Peel) in Recovery of Silver from X-Ray Films

Abstract

Bromelain is a proteolytic enzyme, which is predominately found in all parts of a pineapple plant (Ananas comosus). It has immense application in the pharmaceutical industry as well as in food, cosmetic, and leather industries. However, bromelain from pineapple fruit peels is a less explored source for making valuable products. Therefore, the objective of this study was to characterize and investigate the potential application of bromelain enzyme extracted from pineapple juice processing waste peels in gelatin hydrolysis and removal of silver from X-ray films. Extraction of bromelain was performed with a 1 : 2 ratio (w/v) of the extraction mix, pineapple fruit peel, in phosphate buffer (pH = 7.0). The activity of a crude enzyme was 7.2 U/ml, and it was active in a broad range of pH (2.5–12) and temperature (25–85°C) without losing its activity. This implies that the enzyme is heat tolerant. The optimum temperature and pH of the enzyme were recorded at 70°C and pH 7.0, respectively. At optimum conditions (70°C and pH 7.0), complete hydrolysis of the gelatin layer from X-ray film was observed at 30 and 34 seconds, respectively. The enzyme was repeatedly used more than 50 times without significant loss of its activity. Using a minimum concentration of bromelain (3 ml = 21.6 U) along with phosphate buffer (37 ml), it is possible completely to remove gelatin within 210 seconds. The properties of the enzyme showed that it has promising potential industrial applications for repeated utilization of the enzyme in both silver recovery and recycling of the X-ray film base.

Exploration of a novel protease from Phytolacca dodecandra (Endod) berries for potential application in detergent formulation

“…Samples were withdrawn at 1, 4, 8, 15, 30, 45, 60, 75, 90, 105, and 120 days. The residual activity of the crude enzymes taken from each day was tested at 40°C and pH 10.0 (Anbesaw, 2021). The activity of the crude enzyme at 0 day was considered as 100% activity.…”

“…The potency of the crude protease from P. dodecandra for gelatin removal from used X-ray film was evaluated according to Anbesaw (2021). The reaction was performed under the optimum conditions (pH 10.0 and 45 C) of the enzyme with the reaction mix of 5 mL (7090 U) enzyme and 15 mL Glycine/NaOH buffer.…”

“…This suggests that, in addition to its application in detergent formulations, the protease derived from the Endod plant can also be utilized for the efficient recovery of silver from used X-ray films without causing any damage. Similarly, protease (10 mL) extracted from Pineapple waste (peel), in the presence of 10 mL distilled water, showed the capability to remove gelatin and recover silver from used X-ray films within 34 s (Anbesaw, 2021). However, it was observed that the protease from Endod (5 mL) exhibited significantly higher potency and efficiency in gelatin removal and silver recovery from used X-ray films compared to the protease from Pineapple.…”

“…However, it was observed that the protease from Endod (5 mL) exhibited significantly higher potency and efficiency in gelatin removal and silver recovery from used X-ray films compared to the protease from Pineapple. Related studies presented in Anbesaw (2021) showed that recovery of silver from used films can be performed by protease from microorganisms and plants. But their gelatin removal efficiency is not efficient as compared to the protease investigated in this study.…”

Eco enzim untuk pengolahan air limbah tahu

“…Reaksi enzim hidrolitik mampu hidrolase dan memecah zat organik yang tidak larut menjadi zat organik terlarut lumpur pada kedua kondisi pH enzim tersebut. Aktivitas enzim pada pH 3,5 tidak stabil karena sifat asam amino pada sisi aktif enzim mengalami protonasi dan deprotonasi yang mengionisasi amino asam dan mengubah ikatan ionik, menyebabkan enzim menjadi tidak aktif [32]. Penelitian [33] menyebutkan, tinggi nya TSS sampel setelah dicampur dengan eco enzim, dikarenakan enzim hidrolitik yang ada dalam larutan eco enzim mengandung asam sitrat dalam jumlah yang lebih tinggi dari enzim komersial yang lain.…”