Identification and antimicrobial activities of Streptomyces, Micromonospora, and Kitasatospora strains from rhizosphere soils

Rhizosphere soils are the major habitat of various bacteria, especially the actinobacteria. In this study, 17 actinomyceteswere isolated from rhizosphere soil samples collected from the plants, including Barringtonia racemosa, Albizziaodoratissima, Spondia spinnata, and Azadirachta indica. On the basis of 16S rRNA gene analysis (99.0%–100%similarity), the isolates were belonged to genera Streptomyces (10 isolates), Micromonospora (5 isolates), andKitasatospora (2 isolates). They were identified as Streptomyces sioyaensis (2 isolates), Streptomyces vietnamensis(2 isolates), Streptomyces bungoensis (2 isolates), each of Streptomyces psammoticus, Streptomyces purpurascens,Streptomyces hydrogenans, Streptomyces lucensis; Micromonospora schwarzwaldensis, Micromonospora chersina,Micromonospora terminalae, Micromonospora chaiyaphumensis, Micromonospora rhizosphaerae and two isolatesas Kitasatospora putterlickiae. On the results of antimicrobial activities, three isolates presented the good activitiesagainst Candida albicans ATCC 10231, and Escherichia coli ATCC 25922, while 10 isolates exhibited the goodactivities against Staphylococcus aureus ATCC 25923 and 11 isolates exhibited activities against Bacillus subtilisATCC 6633. Among them, JA03 showed 98.95% similarity of 16S rRNA gene sequence to S. psammoticus NBRC13971T, this isolate might be the novel species of actinomycetes

Bile salt hydrolase activity and cholesterol assimilation of lactic acid bacteria isolated from flowers

A total of 16 isolates of lactic acid bacteria (LAB) from flowers were screened for the bile salt hydrolase activity on MRS(de Man, Rogosa and Sharpe; Difco) agar supplemented with 0.5% (w/v) taurodeoxycholic acid. The isolates were dividedinto two groups based on their phenotypic characteristics and 16S rRNA gene sequence analysis of the representativeisolates. Group I isolates were cocci as the members of genus Enterococcus. Isolates FM1-1, FM1-2, FM12-1, andFM12-2 were identified as Enterococcus durans (100% similarity), isolate FM2-3 was identified as Enterococcusgallinarum (99.92% similarity), while the isolate FM11-2 was identified as Enterococcus lactis (99.77% similarity).Group II isolates were rods as the members of genus Lactobacillus. They were identified as Lactobacillus plantarumsubsp. plantarum (the representative isolates, FM3-1 and FM16-2, showed 100% similarity). Eleven isolates, includingFM1-1, FM1-2, FM2-3, FM3-1, FM4-2, FM11-2, FM12-1, FM12-2, FM14-1, FM14-2, and FM16-2, exhibited bilesalt hydrolase activity. All LAB isolates showed the cholesterol assimilated ability ranged from 9.57% to 51.69%. Theisolate FM11-2 efficiently assimilated the cholesterol with 51.69%.

Distribution and antimicrobial activity of Thai marine actinomycetes

A total of 41 actinomycetes were isolated from marine samples collected in Thailand. On the basis of morphology,chemotaxonomy, and 16S rRNA gene sequence analysis, they were identified as Salinispora (13 isolates),Micromonospora (11 isolates), Nocardia (1 isolate), Verrucosispora (2 isolates), and Streptomyces (14 isolates).The antimicrobial activity screening revealed that two Micromonospora isolates, 12 Salinispora isolates and 10Streptomyces isolates showed activity against Staphylococcus aureus ATCC 25923, Kocuria rhizophila ATCC 9341,Bacillus subtilis ATCC 6633, Escherichia coli NIHJ KC213, Candida albicans KF1, and Mucor racemosus IFO 4581.Based on this study, the production media and strains were the main factors that influenced the antimicrobial activity

Chemical and physical properties of Thai traditional shrimp paste (Ka-pi).

Thai traditional fermented shrimp paste (Ka-pi) is widely consumed as condiment and seasoning ingredient in Thailand. Chemical and physical properties of thirteen shrimp paste samples were examined. The water content and water activity (Aw) of the products ranged from 33.95-52.19 % and 0.64-0.72, respectively while salt concentration was 7.00 to 10.85 %. The nitrogen content varied from 2.87 to 6.85 % (w/w). KS1 showed the highest protein content (42.8 %) followed by SP1 and SP3 (42.4 and 41.3 %), respectively. The predominant amino acids were glutamic acid (70.1-593.9 μg/g), lysine (112.7-546.3 μg/g) and leucine (29.5-544.9 μg/g). Total bacterial cell count in the samples ranged from 1.3x103 - 2.9x105 cfu g-1 while lactic acid bacteria (LAB) were not detected. This study will be provided the information for improving the quality of products in manufacture to meet the demand of consumer.

Characterization and lipolytic activity of lactic acid bacteria isolated from Thai fermented meat.

Twenty six strains of lactic acid bacteria (LAB) were isolated from Thai fermented meat products, including 7 samples of Nham (fermented pork), 7 Sai-krog-prieo (fermented sausage) and one Mum (fermented beef). The isolates were identified as Lactobacillus pentosus (5 isolates), Lactobacillus sp. (11 isolates), Pediococcus pentosaceus (5 isolates) and each isolate of Pediococcus lolii, Leuconostoc fallax, Weissella thailandensis, W. cibaria, and W. paramesenteroides based on their phenotypic characteristics and 16S rRNA gene sequence similarities (99.8-100 %). The isolates were primary screened for their lipolytic activity on agar plates. The rodshaped isolates showed 0.031±0.030-0.938±0.127 U/ml of lipase activity in broth supplemented with Tween 20, Tween 40, Tween 60 or Tween 80. The isolate SS50-1 identified as Lactobacillus pentosus showed the highest activity in Tween 80 (0.938±0.127 U/ml). The coccal isolates showed lipase activity ranged from 0.029±0.006- 1.090±0.033 U/ml when Tween 20, Tween 40, Tween 60 or Tween 80 was used as a substrate. The isolate SS48-4 identified as Pediococcus lolii showed the highest activity in Tween 80 (1.090±0.033 U/ml).

Identification and antimicrobial activity of Streptomyces and Actinoplanes strains from lichens.

Twelve actinomycete strains were isolated from lichens collected in Thailand. On the basis of their phenotypic and chemotaxonomic characteristics including 16S rRNA gene sequence analysis, they were divided into 2 genera, Streptomyces (Group 1, 9 isolates) and Actinoplanes (Group 2, 3 isolates). Isolates LDG1-03 and LDG1-15; LDG1-05 and LDG2-02; LDG1-08; LDG1-16; LDG2-09; LLG1-01; and LLG1-03 were closely related to S. malaysiensis NBRC 16446T (98.95-99.85%); S. lomondensis NBRCT (99.77-99.78%); S. graminearus NBRC 15420T (98.72 %); S. parvulus NBRC 13193T (100%); S. cinereoruber subsp. cinereoruber NBRC 12756T(99.11%); S. seoulensis NBRC 16668T (100%); and S. cinerochromogenes NBRC 13822 T (99.17%) based on 16S rRNA gene sequence analysis, respectively. The isolates LDG1-06, LDG1-22A and LDG1-22B are closely related to A. deccanensis IFO 13994T and A. nipponensis FH 2241 T (97.97-98.93 %), respectively. The isolates in Group 1 contained LL-diaminopimelic acid in cell wall and had MK-9(H6), MK- 9(H8) and MK-9(H4) as the major menaquinones. The isolates in Group 2 contained meso-diaminopimelic acid and had MK-9(H6) and MK-9(H4) as the major menaquinones. Four Streptomyces isolates exhibited antimicrobial activity against Staphylococcus aureus ATCC 25923, Bacillus subtilis ATCC 6633, Kocuria rhizophila ATCC 9341 and Candida albicans ATCC 27853 while Actinoplanes isolate LDG1-06 exhibited against C. albicans ATCC 27853.

Identification of Staphylococcus strain CH1-8 and its oil-degradation.

A lipase-and biosurfactant-producing, Gram-positive, aerobic and coccal bacterium designated as CH1-8 was isolated from Thai fermented fish. It grew optimally at 37 C, pH 7.0, and in the presence of 0-5%, w/v NaCl. The results of phenotypic and chemotaxonomic properties including phylogeneitc tree analysis confirmed that it was belonged to the genus Stayphylococus. The16S rRNA gene sequence analysis revealed that strain CH1-8 was closely related to Staphylococcus xylosus ATCC 29971T (99.11%), therefore it was identified as Staphylococcus xylosus. This strain gradually degraded various types of oils, sunflower oil, palm oil, soybean oil and rice bran oil, including cooking oil. During cultivation at room temperature for 35 days, lipase and biosurfactant activities of strain were 2 units/ml and 52 mN/m, respectively while the cleavage products were almost completely consumed. The maximal percentage of cooking oil hydrolysis by strain CH1-8 was 90% in the absence of NaCl and 60% in the presence of 10%, (w/v) NaCl. Therefore, the quality of wastewater from household will environmentally accepted after treated with strain CH1-8.

Characterization and antimicrobial activity of Streptomyces strains from soils in southern Thailand.

Streptomyces strains are superior to other actinomycete strains in their ability to produce large numbers and varieties of antibiotics. The aim of this research was to study on the identification and antimicrobial activity of Streptomyces strains which were isolated from thirteen soil samples collected around Angthong Islands National Park, Surat Thani province, the southern part of Thailand. Twenty-six strains were isolated by using the dilution plating method on starch casein nitrate agar plate and potato starch-glycerol agar plate. On the basis of phenotypic characteristics and the 16S rRNA gene sequence analysis, they were belonged to the genus Streptomyces and were identified as S. tendae (5 isolates), S. malachitospinus (2 isolates), S. marokkonensis (2 isolates), S. parvulus (2 isolates), S. fragilis (1 isolate), S. diastaticus (1 isolate), S. drozdowiczii (1 isolate), S. olivochromogenes (1 isolate), S. aureus (2 isolates), S. iranensis (1 isolate), S. rapamycinicus (1 isolate), S. yatensis (1 isolate), S. samsunensis (4 isolates) and S. spiralis (2 isolates). On the antimicrobial activity screening, 15 isolates exhibited activity against Bacillus subtilis ATCC 6633, 13 isolates against Kocuria rhizophila ATCC 9341, 6 isolates against Mucor racemosus IFO 4581 and Candida albicans KF1, one isolate against Escherichia coli NIHJ KB213 and 5 isolates against Xanthomonas campestris pv. oryzae KB88.

Characterization of cellulase producing Bacillus and Paenibacillus strains from Thai soils.

Seventeen strains of cellulase producing bacteria were isolated from soil samples collected in Nan province, Thailand. They exhibited cellulase activity as a clear zone surrounded their colonies grown on carboxymethyl cellulose (CMC) agar medium ranged from 0.63 to 2.95 cm in diameter. Their hydrolysis capacity values were 1.65 - 7.55. The bacteria isolated were divided into 2 groups and belonged to genus Bacillus and Paenibacillus based on their phenotypic characteristics and chemotaxonomic characteristics such as meso-diaminopimelic in cell wall peptidoglycan and menaquinones of MK-7. Bacillus strains, P3-1 and P4-6 in Group I, produced maximum cellulase at 0.015 U ml-1. Their optimal pH and temperature for enzyme production and enzyme activity were 7.0 and 50 oC, respectively. The strains P3-1 and P4-6 were closely related to Bacillus velesensis LMG 22478T (100% similarity) whereas representative strain, S10-4 in Group II, was closely related to P. cellulositrophicus KCTC 13135T (98.7% similarity) based on 16S rRNA gene sequence. On the basis of their phenotypic, chemotaxonomic characteristics and phylogenetic analysis of 16S rRNA gene sequence, the strains P3-1 and P4-6 were identified as B. velesensis and the strain S10-4 was a novel species in the genus Paenibacillus.

Screening and identification of cellulase producing bacteria isolated from oil palm meal.

Oil palm (Elaeis guineensis) meal, a by-product of palm oil, is rich in fiber and contains lignocelluloses, which inhibits the absorption of the nutrients has been widely used for animal feed. The improvement of the nutrient absorption is required treating with cellulase enzyme. This study was aimed to isolate, screen and characterize the cellulase producing bacteria. Ten strains of cellulolytic bacteria were isolated from 7 oil palm meal samples collected in Phetchaburi, Prachuap Khiri Khan and Pattani provinces, Thailand. They exhibited the ability to degrade carboxymethyl-cellulose (CMC) based on the decolorization of CMC-basal agar medium using Congo red as a color indicator. They showed the cellulase hydrolysis capacity ranged from 1.56 to 4.14. All isolates were Gram positive rod-shaped bacteria and belonged to Bacillus (8 isolates), Paenibacillus (1 isolate) and Lysinibacillus (1 isolate) based on the phenotypic characteristics and 16S rRNA gene sequence analysis. Their cellulase activity ranged from 0.039±0.002 to 0.233±0.005 IU/ml when they were cultivated in broth.

Characterization and ethanol fermentation of Pichia and Torulaspora strains.

Seventy-two yeasts were isolated from sugarcane juices and sugar process-sediments collected in Thailand by incubated at 30 and 40oC in oxygen-limited condition. Six and eleven isolated yeasts produced ethanol with 0.46 and 0.22 g/g initial glucose at 30 and 40oC, respectively. The highest ethanol production efficacy, 0.30 g/g glucose of maximum ethanol yield at 40oC was found in isolates G1-4(1) and G1-12(3). On the basis of their phenotypic characteristics including the D1/D2 region of the large-subunit ribosomal (LSU) of 26S rRNA gene sequence analysis, the isolates G1-4(1) and G1-12(3) were identified as Pichia kudriavzvii and Torulaspora globosa, respectively.

Characterization and fermentation products of Clostridium butyricum strains isolated from Thai soils.

Five acid forming bacteria, SK3-3, SK3-6B, SK3-7B, SK13-3 and PL20-4S were isolated from soils collected in Samut Songkhram and Phitsanulok provinces. All isolates were Gram-positive, anaerobic, spore-forming, rodshaped bacteria. The isolates were screened for their end product fermentation and were identified based on their phenotypic characteristics and 16S rRNA gene sequence analyses. They were belonged to the genus Clostridium and were closely related to Clostridium butyricum DSM 10702T (99.7-100%) and Clostridium saccharoperbutylacetonicum N1-4T (98.0-98.2%) based on 16S rRNA gene sequence similarity. All 5 isolates were identified as Clostridium butyricum. They produced 4.51-8.90 g/L (19.40-54.82% yield) of L-lactic acid with 0.06-0.12 g/L/h productivity, 6.15-7.52 g/L of acetic acid and 24.32-29.67 g/L of ethanol as the end product fermentation.

Screening and characterization of protease-producing Virgibacillus, Halobacillus and Oceanobacillus strains from Thai fermented fish.

Halophilic bacteria from fermented fish (pla-ra and pla-chom), shrimp paste (ka-pi) and fermented crab] were isolated and screened for protease activities. Twenty-seven isolates exhibited protease specific activities ranged from 0.12 to 3.62 unit/mg protein. Isolate TPPN2-1 from pla-ra produced maximal protease specific activity (3.62 units/mg protein). They were Gram-positive, moderately halophilic rod-shaped bacteria and were divided into 5 groups on the basis of their phenotypic and chemotaxonomic characteristics, DNA-DNA relatedness including the 16S rRNA gene sequences analyses. Three isolates (Group I) were identified as Virgibacillus halodenitrificans, 3 isolates (Group II) as V. marismortui, 7 isolates (Group III) as V. dokdonensis, 10 isolates (Group IVA & IVB) as Halobacillus species and 4 isolates (Group V) as Oceanobacillus iheyensis.

Characterization of lactic acid producing bacteria from Thai sources.

The aim of this research was to study on the isolation and characterization of lactic acid producing bacteria in Thailand. Ten bacterial strains isolated from soils and plant bark and root were screened for their lactic acid production. They were divided into 7 groups based on their phenotypic and chemotaxonomic characteristics including 16S rRNA gene sequence analyses. Four isolates in Group I were identified as P. pentosaceus, and each isolate in Group II to Group VII was identified as Enterococcus casseliflavus, E. hirae, Lactobacillus. plantarum, L. paraplantarum, Bacillus coagulans and Sporolactobacillus terrae, respectively. The isolates in Group I, IV, V and VII produced DL-lactic acid ranged from 54.50-77.31 g/L (45.88-75.11% yield) and 0.76-1.07 g/L.h of productivity. The isolates in Group II, III and VI produced optically pure L (+)- lactic acid ranged from 60.72-89.34 g/L (70.00- 74.45% yield) and 0.84-1.24 g/L.h of productivity. B. coagulans isolate in Group VI could produce the highest optically pure L-lactic acid (99.75%).

Characterization and antimicrobial activity of Amycolatopsis strains isolated from Thai soils.

The isolation and screening of antimicrobial activity of 3 actinomycete strains isolated from soil samples collected in Chaiyaphum, Nan and Phatthalung provinces, Thailand were carried out. Strains S39-7, KC19-1 and K57-1 were belonged to the genus Amycolatopsis based on their phenotypic and chemotaxonomic characteristics. On the basis of 16S rRNA gene sequence analysis, strain S39-7 was closely related to Amycolatopsis albidoflavus KCTC 9471T (99.2%). Strains KC19-1 and K57-1 were closely related to A. kentuckyensis NRRL B-24129T with 99.3 and 99.2% similarity, respectively. All of them contained meso-diaminopimelic acid (DAP) in cell wall peptidoglycan and had MK-9 (H4) as a major menaquinones. The DNA G+C contents of the strains ranged from 67.2 to 73.4 mol%. On secondary screening of antimicrobial activity, the ethyl acetate extract of the fermentation products of strain S39-7 was active against Staphylococcus aureus ATCC 6538, Bacillus subtilis ATCC 6633, Escherichia coli ATCC 25922, Kocuria rhizophila ATCC 9341, and Pseudomonas aeruginosa ATCC 27853 while strain KC 19-1 was active against only S. aureus ATCC 6538. Strain K 57-1 was active against E. coli ATCC 25922 and K. rhizophila ATCC 9341. In addition strain S39-7 could inhibit against methicillin resistant (MRSA) S. aureus 266.