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Oscar P Kuipers - One of the best experts on this subject based on the ideXlab platform.
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increasing the antimicrobial activity of Nisin based lantibiotics against gram negative pathogens
Applied and Environmental Microbiology, 2018Co-Authors: Manuel Montalbanlopez, Oscar P KuipersAbstract:Lantibiotics are ribosomally synthesized and posttranslationally modified antimicrobial compounds containing lanthionine and methyl-lanthionine residues. Nisin, one of the most extensively studied and used lantibiotics, has been shown to display very potent activity against Gram-positive bacteria, and stable resistance is rarely observed. By binding to lipid II and forming pores in the membrane, Nisin can cause the efflux of cellular constituents and inhibit cell wall biosynthesis. However, the activity of Nisin against Gram-negative bacteria is much lower than that against Gram-positive bacteria, mainly because lipid II is located at the inner membrane, and the rather impermeable outer membrane in Gram-negative bacteria prevents Nisin from reaching lipid II. Thus, if the outer membrane-traversing efficiency of Nisin could be increased, the activity against Gram-negative bacteria could, in principle, be enhanced. In this work, several relatively short peptides with activity against Gram-negative bacteria were selected from literature data to be fused as tails to the C terminus of either full or truncated Nisin species. Among these, we found that one of three tails (tail 2 [T2; DKYLPRPRPV], T6 [NGVQPKY], and T8 [KIAKVALKAL]) attached to a part of Nisin displayed improved activity against Gram-negative microorganisms. Next, we rationally designed and reengineered the most promising fusion peptides. Several mutants whose activity significantly outperformed that of Nisin against Gram-negative pathogens were obtained. The activity of the tail 16 mutant 2 (T16m2) construct against several important Gram-negative pathogens (i.e., Escherichia coli, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, Enterobacter aerogenes) was increased 4- to 12-fold compared to that of Nisin. This study indicates that the rational design of Nisin can selectively and significantly improve its outer membrane-permeating capacity as well as its activity against Gram-negative pathogens.IMPORTANCE Lantibiotics are antimicrobial peptides that are highly active against Gram-positive bacteria but that have relatively poor activity against most Gram-negative bacteria. Here, we modified the model lantibiotic Nisin by fusing parts of it to antimicrobial peptides with known activity against Gram-negative bacteria. The appropriate selection of peptidic moieties that could be attached to (parts of) Nisin could lead to a significant increase in its inhibitory activity against Gram-negative bacteria. Using this strategy, hybrids that outperformed Nisin by displaying 4- to 12-fold higher levels of activity against relevant Gram-negative bacterial species were produced. This study shows the power of modified peptide engineering to alter target specificity in a desired direction.
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expanding the genetic code of lactococcus lactis and escherichia coli to incorporate non canonical amino acids for production of modified lantibiotics
Frontiers in Microbiology, 2018Co-Authors: Maike Bartholomae, Tobias Baumann, Jessica H Nickling, David Peterhoff, Ralf Wagner, Nediljko Budisa, Oscar P KuipersAbstract:The incorporation of non-canonical amino acids (ncAAs) into ribosomally synthesized and post-translationally modified peptides, e.g., Nisin from the Gram-positive bacterium Lactococcus lactis, bears great potential to expand the chemical space of various antimicrobials. The ncAA Ne-Boc-L-lysine (BocK) was chosen for incorporation into Nisin using the archaeal pyrrolysyl-tRNA synthetase-tRNAPyl pair to establish orthogonal translation in L. lactis for read-through of in-frame amber stop codons. In parallel, recombinant Nisin production and orthogonal translation were combined in Escherichia coli cells. Both organisms synthesized bioactive Nisin(BocK) variants. Screening of a Nisin amber codon library revealed suitable sites for ncAA incorporation and two variants displayed high antimicrobial activity. Orthogonal translation in E. coli and L. lactis presents a promising tool to create new-to-nature Nisin derivatives.
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the c terminal region of Nisin is responsible for the initial interaction of Nisin with the target membrane
Biochemistry, 1997Co-Authors: Eefjan Breukink, Oscar P Kuipers, Cindy Van Kraaij, R A Demel, Roland J Siezen, Ben De KruijffAbstract:The interaction of Nisin Z and a Nisin Z mutant carrying a negative charge in the C-terminus ([Glu-32]-Nisin Z) with anionic lipids was characterized in model membrane systems, and bacterial membrane systems. We focused on three possible steps in the mode of action of Nisin, i.e., binding, insertion, and pore formation of Nisin Z. Increasing amounts of anionic lipids in both model and natural membranes were found to strongly enhance the interaction of Nisin Z with the membranes at all stages. The results reveal a good correlation between the anionic lipid dependency of the three stages of interaction, of which the increased binding is probably the major determinant for antimicrobial activity. Maximal Nisin Z activity could be observed for negatively charged lipid concentrations exceeding 50-60%, both in model membrane systems as well as in bacterial membrane systems. We propose that the amount of negatively charged lipids of the bacterial target membrane is a major determinant for the sensitivity of the organism for Nisin. Nisin Z induced leakage of the anionic carboxyfluorescein was more efficient as compared to the leakage of the potassium cation. This lead to the conclusion that an anion-selective pore is formed. In contrast to the results obtained for Nisin Z, the binding of [Glu-32]-Nisin Z to vesicles remained low even in the presence of high amounts of negatively charged lipids. The insertion and pore-forming ability of [Glu-32]-Nisin Z were also decreased. These results demonstrate that the C-terminus of Nisin is responsible for the initial interaction of Nisin, i.e., binding to the target membrane.
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functional analysis of promoters in the Nisin gene cluster of lactococcus lactis
Journal of Bacteriology, 1996Co-Authors: P G G A De Ruyter, Marke M Beerthuyzen, Oscar P Kuipers, I J Van Alenboerrigter, W M De VosAbstract:The promoters in the Nisin gene cluster nisABTCIPRKFEG of Lactococcus lactis were characterized by primer extension and transcriptional fusions to the Escherichia coli promoterless beta-glucuronidase gene (gusA). Three promoters preceding the nisA, nisR, and nisF genes, which all give rise to gusA expression in the Nisin-producing strain L. lactis NZ9700, were identified. The transcriptional autoregulation of nisA by signal transduction involving the sensor histidine kinase NisK and the response regulator NisR has been demonstrated previously (0. P. Kuipers, M. M. Beerthuyzen, P. G. G. A. de Ruyter, E. J. Luesink, and W. M. de Vos, J. Biol. Chem. 270: 27299-27304, 1995), and therefore the possible Nisin-dependent expression of gusA under control of the nisR and nisF promoters was also investigated. The nisR promoter was shown to direct Nisin-independent gusA expression in L. lactis MG 1363, which is a Nisin-transposon- and plasmid-free strain. L. lactis NZ9800, which does not produce Nisin because of a deletion in the nisA gene, containing the nisF-gusA fusion plasmid, gave rise to beta-glucuronidase production only after induction by Nisin. A similar regulation was found in L. lactis NZ3900, which contains a single copy of the nisR and nisK genes but no other genes of the Nisin gene cluster. In contrast, when the nisK gene was disrupted, no beta-glucuronidase activity directed by the nisF promoter could be detected even after induction with Nisin. These results show that, like the nisA promoter, the nisF promoter is Nisin inducible. The nisF and nisA promoter sequences have significant similarities and contain a conserved region that could be important for transcriptional control.
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autoregulation of Nisin biosynthesis in lactococcus lactis by signal transduction
Journal of Biological Chemistry, 1995Co-Authors: Oscar P Kuipers, Marke M Beerthuyzen, Pascalle G G A De Ruyter, Evert J Luesink, Willem M De VosAbstract:The post-translationally modified, antimicrobial peptide Nisin is secreted by strains of Lactococcus lactis that contain the chromosomally located Nisin biosynthetic gene cluster nisABTCIPRKFEG. When a 4-base pair deletion is introduced into the structural nisA gene (ΔnisA), transcription of ΔnisA is abolished. Transcription of the ΔnisA gene is restored by adding subinhibitory amounts of Nisin, Nisin mutants, or Nisin analogs to the culture medium, but not by the unmodified precursor peptide or by several other antimicrobial peptides. Upon disruption of the nisK gene, which encodes a putative sensor protein that belongs to the class of two-component regulators, transcription of ΔnisA was no longer inducible by Nisin. Fusion of a nisA promoter fragment to the promoterless reporter gene gusA resulted in expression of gusA in L. lactis NZ9800 (ΔnisA) only upon induction with Nisin species. The expression level of gusA was directly related to the amount of inducer that was added extracellularly. These results provide insight into a new mechanism of autoregulation through signal transduction in prokaryotes and demonstrate that antimicrobial peptides can exert a second function as signaling molecules.
Arash Koocheki - One of the best experts on this subject based on the ideXlab platform.
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Characterization, Release Profile and Antimicrobial Properties of Bioactive Polyvinyl Alcohol-Alyssum homolocarpum Seed Gum- Nisin Composite Film
Food Biophysics, 2019Co-Authors: Leila Monjazeb Marvdashti, Arash Koocheki, Masoud YavarmaneshAbstract:A common goal of active packaging is to improve the shelf life, safety, or quality of packaged foods. The integrity of an active package must be remained in order to prevent the growth of microorganisms on the surface of food. Therefore, active polyvinyl alcohol -Alyssum homolocarpum seed gum (PVA-AHSG) composite films with different Nisin concentrations (3000, 5000 and 10,000 IU) were prepared and their physico-chemical and antimicrobial properties were determined. Addition of Nisin to the composite films increased their water vapor permeability (WVP), elongation at break (EB) and opacity, whereas their total color difference (ΔE), glass transition temperature (Tg), melting temperature (Tm), tensile strength (TS) and young modulus (YM) were decreased. Increasing the Nisin concentration remarkably increased the chain mobility, interactions between polymers and water molecules and also the free volume of polymer matrix. The antimicrobial potential of film against L. monocytogene , S. aureus and E. coli as well as the release of Nisin into phosphate buffer solution (pH 7.2) were investigated. Films containing Nisin had inhibition effect against gram positive pathogens among which L. monocytogenes was the most sensitive bacterium . In liquid media, all films containing Nisin prevented the growth of L. monocytogenes and S. aureus , but it was only the film with 10,000 IU Nisin content which was able to control 100% of the microbial population during incubation time. Nisin release and diffusion coefficient (D) increased as its concentration increased in the film matrix due to the interaction of Nisin with film polymer chains. Therefore, the resultant film had appropriate controlled release property and suitable microbial inhibitory against gram positive bacteria. Graphical Abstract Composite bioactive films based on polyvinyl alcohol- Alyssum homolocarpum seed gum blend and Nisin: Physiochemical characterization and antimicrobial properties. Monjazeb et al. (2017).
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controlled release of Nisin from polyvinyl alcohol alyssum homolocarpum seed gum composite films Nisin kinetics
Food bioscience, 2019Co-Authors: Leila Monjazeb Marvdashti, Masoud Yavarmanesh, Arash KoochekiAbstract:Abstract Antimicrobial biodegradable films based on PVA-AHSG incorporated with Nisin were prepared. These films were characterized for their ability to control the overall release rate of Nisin into foods, which would be needed for active food packaging. The objectives of this study were to assay the biodegradable films for Nisin release, and to investigate their antimicrobial activity against L. innocua. The release kinetics of Nisin from the films were described using Fick's Second Law, mass ratio, partition coefficient, desorption coefficient and the Weibull model. All PVA-AHSG films showed inhibition zones that increased with increasing Nisin concentration. Nisin release increased as its concentration in the film matrix increased. Release of Nisin was faster at higher concentrations, and the diffusion coefficients increased significantly with increasing concentration. The partition coefficient (k) values obtained were 1.42, 0.61 and 0.64 for 3000, 5000 and 10,000 IU of Nisin, respectively. According to the Weibull parameters, Nisin is released following pseudo-Fickian diffusion. Results showed that the PVA-AHSG composite films showed promise for developing controlled release applications with Nisin in aqueous solutions.
Masoud Yavarmanesh - One of the best experts on this subject based on the ideXlab platform.
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Characterization, Release Profile and Antimicrobial Properties of Bioactive Polyvinyl Alcohol-Alyssum homolocarpum Seed Gum- Nisin Composite Film
Food Biophysics, 2019Co-Authors: Leila Monjazeb Marvdashti, Arash Koocheki, Masoud YavarmaneshAbstract:A common goal of active packaging is to improve the shelf life, safety, or quality of packaged foods. The integrity of an active package must be remained in order to prevent the growth of microorganisms on the surface of food. Therefore, active polyvinyl alcohol -Alyssum homolocarpum seed gum (PVA-AHSG) composite films with different Nisin concentrations (3000, 5000 and 10,000 IU) were prepared and their physico-chemical and antimicrobial properties were determined. Addition of Nisin to the composite films increased their water vapor permeability (WVP), elongation at break (EB) and opacity, whereas their total color difference (ΔE), glass transition temperature (Tg), melting temperature (Tm), tensile strength (TS) and young modulus (YM) were decreased. Increasing the Nisin concentration remarkably increased the chain mobility, interactions between polymers and water molecules and also the free volume of polymer matrix. The antimicrobial potential of film against L. monocytogene , S. aureus and E. coli as well as the release of Nisin into phosphate buffer solution (pH 7.2) were investigated. Films containing Nisin had inhibition effect against gram positive pathogens among which L. monocytogenes was the most sensitive bacterium . In liquid media, all films containing Nisin prevented the growth of L. monocytogenes and S. aureus , but it was only the film with 10,000 IU Nisin content which was able to control 100% of the microbial population during incubation time. Nisin release and diffusion coefficient (D) increased as its concentration increased in the film matrix due to the interaction of Nisin with film polymer chains. Therefore, the resultant film had appropriate controlled release property and suitable microbial inhibitory against gram positive bacteria. Graphical Abstract Composite bioactive films based on polyvinyl alcohol- Alyssum homolocarpum seed gum blend and Nisin: Physiochemical characterization and antimicrobial properties. Monjazeb et al. (2017).
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controlled release of Nisin from polyvinyl alcohol alyssum homolocarpum seed gum composite films Nisin kinetics
Food bioscience, 2019Co-Authors: Leila Monjazeb Marvdashti, Masoud Yavarmanesh, Arash KoochekiAbstract:Abstract Antimicrobial biodegradable films based on PVA-AHSG incorporated with Nisin were prepared. These films were characterized for their ability to control the overall release rate of Nisin into foods, which would be needed for active food packaging. The objectives of this study were to assay the biodegradable films for Nisin release, and to investigate their antimicrobial activity against L. innocua. The release kinetics of Nisin from the films were described using Fick's Second Law, mass ratio, partition coefficient, desorption coefficient and the Weibull model. All PVA-AHSG films showed inhibition zones that increased with increasing Nisin concentration. Nisin release increased as its concentration in the film matrix increased. Release of Nisin was faster at higher concentrations, and the diffusion coefficients increased significantly with increasing concentration. The partition coefficient (k) values obtained were 1.42, 0.61 and 0.64 for 3000, 5000 and 10,000 IU of Nisin, respectively. According to the Weibull parameters, Nisin is released following pseudo-Fickian diffusion. Results showed that the PVA-AHSG composite films showed promise for developing controlled release applications with Nisin in aqueous solutions.
Yvonne L Kapila - One of the best experts on this subject based on the ideXlab platform.
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abstract 4500 Nisin zp a food preservative has antitumor potential for head and neck cancer and extends survival
Cancer Research, 2015Co-Authors: Pachiyappan Kamarajan, Takayuki Hayami, Bibiana Matte, Ayyalusamy Ramamoorthy, Francis P Worden, Sunil Kapila, Yang Liu, Yvonne L KapilaAbstract:Proceedings: AACR 106th Annual Meeting 2015; April 18-22, 2015; Philadelphia, PA The use of small antimicrobial agents or bacteriocins, like Nisin, to treat cancer is a new approach that holds great promise. Nisin exemplifies this new approach because it has been used safely in humans for many years as a food preservative, and recent laboratory studies support its anti-tumor potential in head and neck cancer. Previously, we showed that Nisin (2.5%, low content) has antitumor potential in head and neck squamous cell carcinoma (HNSCC) in vitro and in vivo. The current studies explored a naturally occurring variant of Nisin (Nisin ZP; 95%, high content) for its antitumor effects in vitro and in vivo. Nisin ZP induced the greatest level of apoptosis in HNSCC cells compared to low content Nisin. HNSCC cells treated with increasing concentrations of Nisin ZP exhibited increasing levels of apoptosis and decreasing levels of cell proliferation and clonogenic capacity. Nisin ZP-induced apoptosis was defined by increased ethidium bromide and acridine orange (EB/AO) staining and by increased levels of calpain-dependent PARP cleavage. Importantly, Nisin ZP also induced apoptosis dose-dependently in HUVEC endothelial cells and concomitant decreases in vascular sprout formation. Nisin ZP inhibited sphere formation of HNSCC cells in vitro and tumorigenesis in vivo and long term treatment extended survival. In summary, Nisin ZP exhibits greater antitumor effects than low content Nisin, and thus has the potential to serve as a novel therapeutic for HNSCC. Note: This abstract was not presented at the meeting. Citation Format: Pachiyappan Kamarajan, Takayuki Hayami, Bibiana Matte, Yang Liu, Ayyalusamy Ramamoorthy, Francis P. Worden, Sunil Kapila, Yvonne Kapila. Nisin ZP, a food preservative, has antitumor potential for head and neck cancer and extends survival. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 4500. doi:10.1158/1538-7445.AM2015-4500
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Nisin zp a bacteriocin and food preservative inhibits head and neck cancer tumorigenesis and prolongs survival
PLOS ONE, 2015Co-Authors: Pachiyappan Kamarajan, Takayuki Hayami, Bibiana Matte, Theodora E Danciu, Ayyalusamy Ramamoorthy, Francis P Worden, Sunil Kapila, Yvonne L KapilaAbstract:The use of small antimicrobial peptides or bacteriocins, like Nisin, to treat cancer is a new approach that holds great promise. Nisin exemplifies this new approach because it has been used safely in humans for many years as a food preservative, and recent laboratory studies support its anti-tumor potential in head and neck cancer. Previously, we showed that Nisin (2.5%, low content) has antitumor potential in head and neck squamous cell carcinoma (HNSCC) in vitro and in vivo. The current studies explored a naturally occurring variant of Nisin (Nisin ZP; 95%, high content) for its antitumor effects in vitro and in vivo. Nisin ZP induced the greatest level of apoptosis in HNSCC cells compared to low content Nisin. HNSCC cells treated with increasing concentrations of Nisin ZP exhibited increasing levels of apoptosis and decreasing levels of cell proliferation, clonogenic capacity, and sphere formation. Nisin ZP induced apoptosis through a calpain-dependent pathway in HNSCC cells but not in human oral keratinocytes. Nisin ZP also induced apoptosis dose-dependently in human umbilical vein endothelial cells (HUVEC) with concomitant decreases in vascular sprout formation in vitro and reduced intratumoral microvessel density in vivo. Nisin ZP reduced tumorigenesis in vivo and long-term treatment with Nisin ZP extended survival. In addition, Nisin treated mice exhibited normal organ histology with no evidence of inflammation, fibrosis or necrosis. In summary, Nisin ZP exhibits greater antitumor effects than low content Nisin, and thus has the potential to serve as a novel therapeutic for HNSCC.
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Nisin an apoptogenic bacteriocin and food preservative attenuates hnscc tumorigenesis via chac1
Cancer Medicine, 2012Co-Authors: Kathryn Ritchie, Pachiyappan Kamarajan, Di Miao, Yvonne L KapilaAbstract:Nisin, a bacteriocin and commonly used food preservative, may serve as a novel potential therapeutic for treating head and neck squamous cell carcinoma (HNSCC), as it induces preferential apoptosis, cell cycle arrest, and reduces cell proliferation in HNSCC cells, compared with primary keratinocytes. Nisin also reduces HNSCC tumorigenesis in vivo. Mechanistically, Nisin exerts these effects on HNSCC, in part, through CHAC1, a proapoptotic cation transport regulator, and through a concomitant CHAC1-independent influx of extracellular calcium. In addition, although CHAC1 is known as an apoptotic mediator, its effects on cancer cell apoptosis have not been examined. Our studies are the first to report CHAC1's new role in promoting cancer cell apoptosis under Nisin treatment. These data support the concept that Nisin decreases HNSCC tumorigenesis in vitro and in vivo by inducing increased cell apoptosis and decreased cell proliferation; effects that are mediated by activation of CHAC1, increased calcium influxes, and induction of cell cycle arrest. These findings support the use of Nisin as a potentially novel therapeutic for HNSCC, and as Nisin is safe for human consumption and currently used in food preservation, its translation into a clinical setting may be facilitated.
Ali Demirci - One of the best experts on this subject based on the ideXlab platform.
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Nisin Production by Immobilized Microbial Cell Culture during Batch and Fed-Batch Fermentations with Various pH Profiles
Agricultural Engineering International: The CIGR Journal, 2008Co-Authors: Todd Jay Miserendino, Ali Demirci, Thunyarat PongtharangkulAbstract:In this study, Nisin production has been enhanced by using batch and fed-batch fermentation with calcium-alginate immobilized cell culture. Due to the inhibitory effects of original phosphate rich growth medium on the immobilizing beads, an altered complex growth medium for Nisin production was used. Various pH profiles were evaluated for both batch and fed-batch fermentations. For batch fermentations, a 2.1 fold higher Nisin activity was obtained by allowing the pH to drop freely after 4 hrs of fermentation at constant pH. A periodic pH profile exhibited a detrimental effect on Nisin production during batch fermentations. For fed-batch fermentations, a 2.9 fold higher Nisin activity was obtained by allowing the pH to remain at pH of 6.8. Approximately the same maximum concentration, 3300 IU/ml, of Nisin was observed when the best pH profile for batch and fed batch experiments were compared. The results also showed that immobilized cell culture can be used in order to improve Nisin fermentation for both batch and fed-batch fermentation.
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Effects of fed-batch fermentation and pH profiles on Nisin production in suspended-cell and biofilm reactors
Applied Microbiology and Biotechnology, 2006Co-Authors: Thunyarat Pongtharangkul, Ali DemirciAbstract:A biofilm reactor not only shortens the lag phase of Nisin production, but also enhances Nisin production when combined with an appropriate pH profile. Due to the substrate inhibition that takes place at high levels of carbon source, fed-batch fermentation was proposed as a better alternative for Nisin production. In this study, the combined effects of fed-batch fermentation and various pH profiles on Nisin production in a biofilm reactor were evaluated. The tested pH profiles include 1) a constant pH profile at 6.8 (profile 1), 2) a constant pH profile with an autoacidification after 4 h (profile 2), and 3) a step-wise pH profile with pH adjustment every 2 h (profile 3). When profile 1 was applied, fed-batch fermentation enhanced Nisin production for both suspended-cell (4,188 IU ml^−1) and biofilm (4,314 IU ml^−1) reactors, yielded 1.8- and 2.3-fold higher Nisin titer than their respective batch fermentation. On the other hand, pH profiles that include periods of autoacidification (profiles 2 and 3) resulted in a significantly lower Nisin production in fed-batch fermentation (2,494 and 1,861 IU ml^−1 for biofilm reactor using profile 2 and 3, respectively) due to toxicity of excess lactic acid produced during the fermentation. Overall, this study suggested that fed-batch fermentation can be successfully used to enhance Nisin production for both suspended-cell and biofilm reactors.
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Nisin Production by Immobilized Cell Culture during Batch and Fed-Batch Fermentations with Various pH Profiles
2006 Portland Oregon July 9-12 2006, 2006Co-Authors: Todd Jay Miserendino, Ali Demirci, Thunyarat PongtharangkulAbstract:In this study, Nisin production has been enhanced by using batch and fed-batch fermentation with calcium-alginate immobilized cell culture. Due to the detrimental effects of original phosphate rich growth medium on the immobilizing beads, an altered complex growth medium for Nisin production was used. Various pH profiles were evaluated for both batch and fed-batch fermentations. For batch fermentations, a 2.1 fold higher Nisin activity was obtained by allowing the pH to drop freely after 4 hrs of fermentation at constant pH. A step-wise pH profile exhibited a detrimental effect on Nisin production during batch fermentations. For fed-batch fermentations, a 2.9 fold higher Nisin activity was obtained by allowing the pH to remain at a constant pH of 6.8. The results clearly showed that immobilized cell culture can be used in order to improve Nisin fermentation for both batch and fed-batch fermentation.
