title: Antibacterial activity of papain and bromelain on Alicyclobacillus spp.
abstract: Alicyclobacillus spp. are spore forming bacteria that are often related to the deterioration of acidic products such as beverages and citrus juices. After the process of industrial pasteurization, the spore produced by the bacteria can germinate and the microorganism can grow, causing sensory abnormalities in the product. Alternative biopreservatives, such as the antimicrobial compounds, are of considerable importance to the food industry. Papain and bromelain are proteolytic enzymes derived frompapaya and pineapple, respectively. These enzymes are widely used in medicine and in the pharmaceutical and food industries, but while some studies have described their antibacterial action, no studies of the Alicyclobacillus spp. exist. The aimof this studywas to analyze the antibacterial effect of papain and bromelain on Alicyclobacillus spp. through 1) determining minimum inhibitory and bactericidal concentration (MIC and MBC); 2) determining the death time curve of the micro-organism in the presence and absence of enzymes; and 3) investigating the enzymatic mechanism on the microorganism. The antibacterial activity of enzymes in combination with nisin was also evaluated. The results showed that for the Alicyclobacillus acidoterrestris strain, the MIC of papain was 0.98 μg/mL and the MBC was 3.91 μg/mL, while theMIC of bromelain was 62.5 μg/mL and the MBCwas 250 μg/mL. The concentration of 4 ×MIC for both the enzymes was sufficient to eliminate 4 logs of the micro-organism after 24 h of incubation. Through the use of enzyme inhibitors specific for cysteine proteases, it was found that the antibacterial activity of papain and bromelain is not related to its proteolytic activity, butmay be related to other activities, such as amidse and esterase. The synergistic activity of the enzymes revealed a fractional inhibitory concentration (FIC) level of 0.16. Combination with nisin revealed an FIC of 0.25 for papain and 0.19 for bromelain, indicating synergism between both compounds. The application of enzymes in reconstituted orange juice contaminated with A. acidoterrestris was found to be effective, as after 48 h of incubation, at three different temperatures, the initial microbial population was eliminated. This study showed that the enzymes papain and bromelain have an antibacterial effect on A. acidoterrestris.
authors.affiliation: Post-Graduate Program in Food Science, State University of Maringá, Av. Colombo, 5790, Maringá 87020-900, Paraná, Brazil.
authors.forename: Márcia Maria
authors.initials: MM
authors.lastname: dos Anjos
authors.affiliation: Post-Graduate Program in Food Science, State University of Maringá, Av. Colombo, 5790, Maringá 87020-900, Paraná, Brazil.
authors.forename: Angela Aparecida
authors.initials: AA
authors.lastname: da Silva
authors.affiliation: Post-Graduate Program in Food Science, State University of Maringá, Av. Colombo, 5790, Maringá 87020-900, Paraná, Brazil.
authors.forename: Isabela Carolini
authors.initials: IC
authors.lastname: de Pascoli
authors.affiliation: Department of Clinical Analysis and Biomedicine, State University of Maringá, Av. Colombo, 5790, Maringá 87020-900, Paraná, Brazil.
authors.forename: Jane Martha Graton
authors.initials: JM
authors.lastname: Mikcha
authors.affiliation: Department of Basic Health Sciences, State University of Maringá, Av. Colombo, 5790, Maringá 87020-900, Paraná, Brazil.
authors.forename: Miguel
authors.initials: M
authors.lastname: Machinski
authors.affiliation: Department of Biochemistry, State University of Maringá, Av. Colombo, 5790, Maringá 87020-900, Paraná, Brazil.
authors.forename: Rosane Marina
authors.initials: RM
authors.lastname: Peralta
authors.affiliation: Department of Basic Health Sciences, State University of Maringá, Av. Colombo, 5790, Maringá 87020-900, Paraná, Brazil. Electronic address: baafilho@uem.com.
authors.forename: Benício Alves
authors.initials: BA
authors.lastname: de Abreu Filho
mesh_terms: D056450:Alicyclobacillus / Q000187:drug effects*; D000581:Amidohydrolases / Q000378:metabolism; D031230:Ananas / Q000201:enzymology; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D001628:Beverages / Q000382:microbiology; D001963:Bromelains / Q000494:pharmacology*; D029441:Carica / Q000201:enzymology; D032084:Citrus sinensis / Q000382:microbiology; D057056:Cysteine Proteases / Q000378:metabolism; D015853:Cysteine Proteinase Inhibitors / Q000737:chemistry; D004357:Drug Synergism; D004950:Esterases / Q000378:metabolism; D008826:Microbial Sensitivity Tests; D009561:Nisin / Q000494:pharmacology*; D010206:Papain / Q000494:pharmacology*; D061352:Pasteurization
chemical_list: D000900:Anti-Bacterial Agents; D015853:Cysteine Proteinase Inhibitors; D009561:Nisin; D001963:Bromelains; D004950:Esterases; D057056:Cysteine Proteases; D010206:Papain; C091760:stem bromelain; D000581:Amidohydrolases; C019665:amidase; C102526:nisin A
keywords: Alicyclobacillus; Bromelain; Orange juice; Papain