Lichens are generally known as self-sufficient symbiotic life-form between fungus and algae/cyano... more Lichens are generally known as self-sufficient symbiotic life-form between fungus and algae/cyanobacteria, also provide shelter for a wide range of beneficial bacteria. Besides, bacterial derived biodegradable polyhydroxyalkanoate (PHA) is currently grabbing the attention of many researchers as a promising alternative of non-degradable plastics. This study was conducted to develop a new method of PHA production using unexplored lichen-associated bacteria, which can simultaneously degrade two ubiquitous industrial toxins, anthracene and naphthalene. Here, 49 lichen-associated bacteria were isolated and tested for PHA synthesis. During the GC-MS analysis, a potential strain of EL19 was found to be 3-hydroxyhexanoate (3-HHx) accumulator and identified as Pseudomonas sp. based on the 16S rRNA sequencing. GC analysis revealed that EL19 was capable of accumulating 30.62% and 19.63% of 3-HHx from naphthalene and anthracene, respectively, resulting in significant degradation of 98% and 96% of naphthalene and anthracene, respectively within seven days. Moreover, the highly expressed phaC gene verified the genetic basis of PHAmcl production under nitrogen starvation condition. Thus, this study strongly supports the hypothesis that lichen-associated bacteria can detoxify naphthalene and anthracene, store energy for extreme conditions, and probably help the associated lichen to live in extreme condition. So far, this is the first investigation of lichen-associated bacteria that might utilize harmful toxins as the feasible supplements and convert anthracene and naphthalene into eco-friendly 3-HHx. Implementation of the developed method would reduce the production cost of PHAmcl while removing harmful waste products.
During the course of investigation of indigenous prokaryotic species in Korea, a total of 30 bact... more During the course of investigation of indigenous prokaryotic species in Korea, a total of 30 bacterial strains belonging to the phylum Firmicutes were isolated from diverse environmental sites such as soil, avian feces, wastewater treatment plants, fermented vegetables, seawater, algae, sea cucumber, octopus and tidal flat sediment. Phylogenetic analysis based on 16S rRNA gene sequences revealed that each strain showed high sequence similarity (≥98.7%) to the closest type strain and formed robust phylogenetic clade with the most closely related species in the phylum Firmicutes. To date, there is no official record of these 30 species in Korea. Therefore, we report 26 species of the 12 genera in the order Bacillales and 4 species of 4 genera in the order of Lactobacillales which have not been reported in Korea. Morphological and biotechnological characteristics, isolation sources and NIBR deposit numbers are described in the species descriptions.
Comprehensive Reviews in Food Science and Food Safety, 2018
Food poisoning and foodborne diseases are a growing public health concern worldwide. Approximatel... more Food poisoning and foodborne diseases are a growing public health concern worldwide. Approximately 30 known and many unknown pathogens are the main culprits for these conditions. Biofilms are a heterogeneous living-form of pathogens and are considered a safe haven for their pathogenicity. In the field of food processing, the persistence of biofilms results in an increased likelihood of food contamination, which ultimately compromises overall food quality and safety. Because of the robust heterogeneity and resistant phenotypic nature of biofilms, the impairment of biofilms is very challenging when using conventional cleaning agents/antibiotics. Therefore, the development of alternative approaches is of great interest to the food industry. Recently, many researchers have found that use of enzymes can provide an exciting and effective therapeutic approach for solving biofilm-associated problems in the food industry, because enzymes are involved in almost every stage of biofilm detachment and degradation. Here, we describe biofilm-associated problems in the food industry and recent advances in enzyme-based biofilm impairment strategies. We also highlight major limitations, challenges, and possible prospects of enzyme-based biofilm-targeting technologies.
International journal of systematic and evolutionary microbiology, 2017
An aerobic, Gram-staining-variable, rod-shaped, endospore-forming and motile bacterial strain, de... more An aerobic, Gram-staining-variable, rod-shaped, endospore-forming and motile bacterial strain, designated CJ6 T , was isolated from a tidal flat on Ganghwa Island, South Korea. The isolate was characterized based on a polyphasic taxonomy approach. Strain CJ6 T grew optimally on R2A agar media at 30 C and pH 7. Phylogenetic analysis based on the 16S rRNA gene sequence revealed that strain CJ6 T belonged to the genus Paenibacillus, displaying the highest sequence similarity to Paenibacillus vulneris CCUG 53270 T (97.0 %) and clearly defined strain CJ6 T as a novel species within the genus. The G+C content of the genomic DNA was 49.9 mol%. The major polar lipid contents of strain CJ6 T were phosphatidylmonomethylethanolamine, diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine and unidentified glycolipids. MK-7 was detected as the major respiratory quinone. The dominant fatty acid was anteiso-C 15 : 0. Analyses of phylogenetic, phenotypic, biochemical and chemotaxonomic characteristics indicated that strain CJ6 T was distinguishable from its closely related type strains. Therefore, strain CJ6 T represents a novel species in the genus Paenibacillus, for which name Paenibacillus limicola sp. nov. is proposed; the type strain is CJ6 T (=KACC 19303 T =JCM 32079 T). The genus Paenibacillus was first proposed by Ash et al. [1] as a member of the 'group 3 bacilli' within the genus Bacillus with 11 Bacillus species. At the time of writing, the genus contains more than 213 novel species with validly published names (www.bacterio.net/paenibacillus.html). Typically, members of this genus are either facultatively anaerobic or strictly aerobic, rod-shaped, comprise anteiso-C 15 : 0 as the major fatty acid, and show a range of the G+C content from 39 to 54 mol% [2]. The purpose of the present study was to establish the taxonomic position of the novel Paenibacillus-like strain CJ6 T based on polyphasic taxonomy. Strain CJ6 T was isolated from the tidal flat of Ganghwa Island (37 36¢ 58.40 † N 126 22¢ 37.40 † E), South Korea through a standard dilution plating technique on R2A agar (BD) media. The strain was routinely cultivated on R2A at 30 C for 3 days and preserved at À80 C with 30 % (w/v) glycerol solution.
International Journal of Fisheries and Aquatic Studies, 2016
Bacterial samples had been isolated from clinically detected diseased juvenile Pangasius, collect... more Bacterial samples had been isolated from clinically detected diseased juvenile Pangasius, collected from Mymensingh, Bangladesh. Primarily, the isolates were found as Gram-negative, motile, oxidase-positive, fermentative, and O/129 resistant Aeromonas bacteria. The species was exposed as Aeromonas hydrophila from esculin hydrolysis test. Ten isolates of A. hydrophila were identified from eye lesions, kidney, and liver of the infected fishes. Further characterization of A. hydrophila was accomplished using API-20E and antibiotic sensitivity test. Isolates were highly resistant to amoxyclav among ten different antibiotics. All isolates were found as immensely pathogenic to healthy fishes while intraperitoneal injection. Histopathologically, necrotic hematopoietic tissues with pyknotic nuclei, mild hemorrhage, and wide vacuolation in kidney, liver, and muscle were principally noticed due to Aeromonad infection. So far, this is the first full note on characterizing A. hydrophila from diseased farmed Pangasius in Bangladesh. The present findings will provide further direction to develop theranostic strategies of A. hydrophila infection.
Lichens are generally known as self-sufficient symbiotic life-form between fungus and algae/cyano... more Lichens are generally known as self-sufficient symbiotic life-form between fungus and algae/cyanobacteria, also provide shelter for a wide range of beneficial bacteria. Besides, bacterial derived biodegradable polyhydroxyalkanoate (PHA) is currently grabbing the attention of many researchers as a promising alternative of non-degradable plastics. This study was conducted to develop a new method of PHA production using unexplored lichen-associated bacteria, which can simultaneously degrade two ubiquitous industrial toxins, anthracene and naphthalene. Here, 49 lichen-associated bacteria were isolated and tested for PHA synthesis. During the GC-MS analysis, a potential strain of EL19 was found to be 3-hydroxyhexanoate (3-HHx) accumulator and identified as Pseudomonas sp. based on the 16S rRNA sequencing. GC analysis revealed that EL19 was capable of accumulating 30.62% and 19.63% of 3-HHx from naphthalene and anthracene, respectively, resulting in significant degradation of 98% and 96% of naphthalene and anthracene, respectively within seven days. Moreover, the highly expressed phaC gene verified the genetic basis of PHAmcl production under nitrogen starvation condition. Thus, this study strongly supports the hypothesis that lichen-associated bacteria can detoxify naphthalene and anthracene, store energy for extreme conditions, and probably help the associated lichen to live in extreme condition. So far, this is the first investigation of lichen-associated bacteria that might utilize harmful toxins as the feasible supplements and convert anthracene and naphthalene into eco-friendly 3-HHx. Implementation of the developed method would reduce the production cost of PHAmcl while removing harmful waste products.
During the course of investigation of indigenous prokaryotic species in Korea, a total of 30 bact... more During the course of investigation of indigenous prokaryotic species in Korea, a total of 30 bacterial strains belonging to the phylum Firmicutes were isolated from diverse environmental sites such as soil, avian feces, wastewater treatment plants, fermented vegetables, seawater, algae, sea cucumber, octopus and tidal flat sediment. Phylogenetic analysis based on 16S rRNA gene sequences revealed that each strain showed high sequence similarity (≥98.7%) to the closest type strain and formed robust phylogenetic clade with the most closely related species in the phylum Firmicutes. To date, there is no official record of these 30 species in Korea. Therefore, we report 26 species of the 12 genera in the order Bacillales and 4 species of 4 genera in the order of Lactobacillales which have not been reported in Korea. Morphological and biotechnological characteristics, isolation sources and NIBR deposit numbers are described in the species descriptions.
Comprehensive Reviews in Food Science and Food Safety, 2018
Food poisoning and foodborne diseases are a growing public health concern worldwide. Approximatel... more Food poisoning and foodborne diseases are a growing public health concern worldwide. Approximately 30 known and many unknown pathogens are the main culprits for these conditions. Biofilms are a heterogeneous living-form of pathogens and are considered a safe haven for their pathogenicity. In the field of food processing, the persistence of biofilms results in an increased likelihood of food contamination, which ultimately compromises overall food quality and safety. Because of the robust heterogeneity and resistant phenotypic nature of biofilms, the impairment of biofilms is very challenging when using conventional cleaning agents/antibiotics. Therefore, the development of alternative approaches is of great interest to the food industry. Recently, many researchers have found that use of enzymes can provide an exciting and effective therapeutic approach for solving biofilm-associated problems in the food industry, because enzymes are involved in almost every stage of biofilm detachment and degradation. Here, we describe biofilm-associated problems in the food industry and recent advances in enzyme-based biofilm impairment strategies. We also highlight major limitations, challenges, and possible prospects of enzyme-based biofilm-targeting technologies.
International journal of systematic and evolutionary microbiology, 2017
An aerobic, Gram-staining-variable, rod-shaped, endospore-forming and motile bacterial strain, de... more An aerobic, Gram-staining-variable, rod-shaped, endospore-forming and motile bacterial strain, designated CJ6 T , was isolated from a tidal flat on Ganghwa Island, South Korea. The isolate was characterized based on a polyphasic taxonomy approach. Strain CJ6 T grew optimally on R2A agar media at 30 C and pH 7. Phylogenetic analysis based on the 16S rRNA gene sequence revealed that strain CJ6 T belonged to the genus Paenibacillus, displaying the highest sequence similarity to Paenibacillus vulneris CCUG 53270 T (97.0 %) and clearly defined strain CJ6 T as a novel species within the genus. The G+C content of the genomic DNA was 49.9 mol%. The major polar lipid contents of strain CJ6 T were phosphatidylmonomethylethanolamine, diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine and unidentified glycolipids. MK-7 was detected as the major respiratory quinone. The dominant fatty acid was anteiso-C 15 : 0. Analyses of phylogenetic, phenotypic, biochemical and chemotaxonomic characteristics indicated that strain CJ6 T was distinguishable from its closely related type strains. Therefore, strain CJ6 T represents a novel species in the genus Paenibacillus, for which name Paenibacillus limicola sp. nov. is proposed; the type strain is CJ6 T (=KACC 19303 T =JCM 32079 T). The genus Paenibacillus was first proposed by Ash et al. [1] as a member of the 'group 3 bacilli' within the genus Bacillus with 11 Bacillus species. At the time of writing, the genus contains more than 213 novel species with validly published names (www.bacterio.net/paenibacillus.html). Typically, members of this genus are either facultatively anaerobic or strictly aerobic, rod-shaped, comprise anteiso-C 15 : 0 as the major fatty acid, and show a range of the G+C content from 39 to 54 mol% [2]. The purpose of the present study was to establish the taxonomic position of the novel Paenibacillus-like strain CJ6 T based on polyphasic taxonomy. Strain CJ6 T was isolated from the tidal flat of Ganghwa Island (37 36¢ 58.40 † N 126 22¢ 37.40 † E), South Korea through a standard dilution plating technique on R2A agar (BD) media. The strain was routinely cultivated on R2A at 30 C for 3 days and preserved at À80 C with 30 % (w/v) glycerol solution.
International Journal of Fisheries and Aquatic Studies, 2016
Bacterial samples had been isolated from clinically detected diseased juvenile Pangasius, collect... more Bacterial samples had been isolated from clinically detected diseased juvenile Pangasius, collected from Mymensingh, Bangladesh. Primarily, the isolates were found as Gram-negative, motile, oxidase-positive, fermentative, and O/129 resistant Aeromonas bacteria. The species was exposed as Aeromonas hydrophila from esculin hydrolysis test. Ten isolates of A. hydrophila were identified from eye lesions, kidney, and liver of the infected fishes. Further characterization of A. hydrophila was accomplished using API-20E and antibiotic sensitivity test. Isolates were highly resistant to amoxyclav among ten different antibiotics. All isolates were found as immensely pathogenic to healthy fishes while intraperitoneal injection. Histopathologically, necrotic hematopoietic tissues with pyknotic nuclei, mild hemorrhage, and wide vacuolation in kidney, liver, and muscle were principally noticed due to Aeromonad infection. So far, this is the first full note on characterizing A. hydrophila from diseased farmed Pangasius in Bangladesh. The present findings will provide further direction to develop theranostic strategies of A. hydrophila infection.
Uploads
Papers by shamsun nahar