Analysis of bacterial growth parttern in bioprocessing of polyhydroxyalkanoates from waste oil by Pseudomonas oleovorans

Pseudomonas oleovorans NCIMB 6576 and Ralstonia eutropha NCIMB 10442 were used for the production of Polyhydroxyalkanoates (PHA) from industrial waste cooking oils, the bacteria were cultured on tryptone soya broth (TSB) and Tryptone soya agar (TSA). The growth pattern of the bacteria, serial dilution and viable counting was done using the Miles and Misra method, 0.5ml (500 µl) of the sample was transferred aseptically into test tubes filled with 4.5ml ringer solution (1/4 strength) resulting in a ten-fold dilution, the growth curve of the cultures of P. oleovorans NCIMB6576 grown on TSB with and without PS oil sample shows error bars in the graph for each point depicting the standard error of the mean. The initial viable count ranges between 6.37 log10 cfu/ml and 5.1 log10 cfu/ml. The viable count reached its peak after 30 hours giving approximately 9.7 log10 cfu/ml for P. oleovorans NCIMB6576 with PS oil and 9.24 log10 cfu/ml after 30 hours as well without the oil, showing that maximum cell count was attained at the same time. The growth curves of P. oleovorans NCIMB6576 grown on TSB with and without the oil sample TS, where the errors bars depicts the standard errors of the means on each point. The initial viable count at the start of the experiments shows that for P. oleovorans NCIMB6576 grown with the oil, there was an initial viable count of 6.1 log10 cfu/ml as compared to 5.1 log10 cfu/ml without the oil respectively. It was observe that the time at which maximum cell counts was attained is slightly longer when the oil was not used as a carbon source (30 hours) as compared to the oil control (27 hours). A decline in cell count is also noticeable after 30 hours until it reaches its minimum value of 9.4 log.10 cfu/ml after 48 hours in the experiment involving the oil sample TS.

Polyhydroxyalkanoates (PHAs), bioprocessing using waste oil

Pseudomonas oleovorans NCIMB 6576 and Ralstonia eutropha NCIMB 10442 were used for the production of Polyhydroxyalkanoates (PHA) from industrial waste cooking oils, the bacteria were cultured on tryptone soya broth (TSB) and Tryptone soya agar (TSA). P. oleovorans NCIMB6576 gave a better percentage PHB yield (8.2%) with PS oil as carbon source as compared to 6.45% with TS oil. However, a very low yield (0.64%) was recorded when P. oleovorans NCIMB6576 was grown on TSB without the oils as carbon source. Ralstonia eutropha NCIMB 10442 gave an appreciable yield of 13.63% and 14.80% with PS and TS oil samples respectively as carbon source with negligible variation in the yields. The results obtained across all experiments were compared with one another. The SEM images from the PHB samples generated from the experiments shows that there is a slight difference in the surface morphologies of the PHB with respect to the oil samples as well as the different bacteria used in the experiment.

Potential of Moringa (Moringa oleifera) leaf extract to inhibit the growth of pathogenic bacteria Edwardsiella tarda

This study analyzed the antibacterial activity of Moringa oliefera leaf extract against the growth of Edwardsiella tarda bacteria. This study aims to determine the antibacterial activity of Moringa leaf extract (M. oliefera) against the growth of E.tarda bacteria. Inhibition testing is done by diffusion method (disc test). The disc test used five variations of concentration of 75 mg/L, 150 mg/L, 225 mg/L, 300 mg/L, and 375 mg/L on TSA (Tryptone Soya Agar) media and incubated for 2x24 hours. As a positive control, an antibiotic in the form of chloramphenicol was used. (5 mg/L) Moreover, distilled water was used as a negative control.Moringa leaf extract (M. oliefera) contains natural active compounds, bacteriostatic antibacterials, due to decreased bacterial growth after 48 hours of incubation. The highest inhibition diameter of E. tarda was 12.95 mm at a concentration of 375 mg/L after 24 hours incubation and decreased by 11.02 mm after 48 hours incubation. The highest inhibitory effectiveness was at a concentration of 375 mg/L with an effectiveness of 58.8%, while the effectiveness of the decrease was 48.1% after 48 hours of incubation.

In Vitro Analysis of Antibacterial Activities of Curry Leaf (Murraya koenigii) Extract Towards Bacteria Edwardsiella tarda

This study analyzed the antibacterial activity of curry leaf extract (Murraya koenigii) on the growth of Edwardsiella tarda bacteria. This study aims to determine the bioactivity and antibacterial effectiveness of M. koenigii leaf extract against the growth of E.tarda bacteria. Inhibition test was carried out by delusion (MIC test) and diffusion (disc test) methods. MIC test used 5 variations of concentration: 1 mg/L, 10 mg/L, 100 mg/L, 500 mg/L and 1,000 mg/L on TSB (Tryptone Soya Broth) media; it was incubated for 24 hours. While the disc test used 5 variations of concentration: 100 mg/L, 200 mg/L, 300 mg/L, 400 mg/L and 500 mg/L on TSA (Tryptone Soya Agar) media and incubated for 2x24 hours. Chloramphenicol (5 mg/L) was used as a positive control, and distilled water was used as a negative control. M. koenigii leaf extract contains natural bioactive; it was bacteriostatic antibacterial due to bacteria's growth after 48 hours incubation. The highest inhibition diameter of E.tarda was 7,20 mm at a concentration of 500 mg/L after 24 hours incubation. The highest inhibitory effectiveness was at a concentration of 500 mg/L with effectivity 56.3%, while it declined to 46,44% after 48 hours incubation.

Paenibacillus cymbidii sp. nov., isolated from Cymbidium goeringii roots

A Gram-stain-variable, aerobic, rod-shaped, endospore-forming strain R196T) was isolated from internal tissues of roots of Cymbidium goeringii. Cells were motile with peritrichous flagella. The colonies were light pink on tryptone soya agar medium. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain R196T fell into a phylogenetic cluster belonging to the genus Paenibacillus . Strain R196T was closely related to Paenibacillus cavernae C4-5T and Paenibacillus contaminans CKOBP-6T with 93.6 and 93.3% sequence similarities, respectively. The major cellular polar lipids were diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol, three unidentified phospholipids, two unidentified aminophospholipids and an unidentified aminolipid. The dominant respiratory quinone was MK-7. The main cellular fatty acids were anteiso-C15 : 0 (53.01%), C16 : 0 (13.04%) and iso-C16 : 0 (10.80%). The genome size of R196T was 9.45 Mb, containing 7617 predicted protein-coding genes, with a DNA G+C content of 57.7 mol%. Based on the results of phenotypic, chemotaxonomic and whole-genome analyses, strain R196T represents a novel species of the genus Paenibacillus , for which the name Paenibacillus cymbidii sp. nov. is proposed. The type strain is R196T (=ACCC 61713T=KCTC 33718T).

Antimicrobial Efficacy of Calcium Hydroxide and Triple Antibiotic Paste Combination on E. faecalis Biofilm- an In vitro Study

Calcium hydroxide (CH) is an intracanal medicament that has been widely used in endodontics, which can eliminate bacteria because of its high alkalinity. However, E. faecalis is resistant to CH. Triple antibiotic paste (TAP) is a mixture of ciprofloxacin, minocycline, and metronidazole, and is highly effective against E. faecalis. Hence the main aim of this study was to find the antimicrobial efficacy of CH and TAP combination against E. faecalis. The study was done by agar diffusion method, three wells were punched in Tryptone soya agar and filled with CH, TAP, and the combination of both. The zone of inhibition values was recorded and subjected to statistical analysis using SPSS. One way ANOVA and Post Hoc tests were used to compare the means. The combination of CH with TAP was found to be significantly better than CH and TAP used alone (p-value <0.05).Within the limits of this study, it can be concluded that TAP is more efficient when compared with CH,The combination of CH and TAP proved to be more effective when compared to the two when used alone.

Isolation, Characterization and Pathogenicity of Edwardsiella tarda a Causative Disease on Freshwater Fish in Yogyakarta

Edwarsiella tarda is a cosmopolitan bacterium and is a cause of Edwardsiellosis in various fish species. The bacterial infection causes large losses on aquaculture in Asia, especially Japan. This study was conducted to isolate and characterize E. tarda as causative disease in freshwater fishes, and to determine its pathogenicity to catfish (Pangasius sp.). Bacteria were isolated from kidney of diseased fishes on Tryptone Soya Agar medium. Identification was conducted based on morphological colonies, morphological cells and biochemical tests. Fulfillment of Koch Postulates was done by injecting bacteria intraperitoneally on 7-9 cm fishes at dose of 107 cfu/fish. Pathogenicity test was carried out by intraperitoneal injection at 104, 105, 106, and 107 cfu/fish to 7-9 cm-catfish (Pangasius sp.) and followed by observation of disease signs and mortality every six hours for 7 days. Pathogenicity was determined as Lethal Dosage (LD50) using Dragstedt Behrens method. In this research we have isolated three isolates E. tarda causing disease in fishes. The clinical signs of this disease were lose of pigmentation over the lession, swollen of stomach, haemorhage on fins , small cutaneous lesions, and necrotic on fins area. The LD50 of E. tarda isolate L2, L3, and N3 were 4.64 ± 0.35x105, 1.54 ± 0.07x105, and 1.13 ± 0.13x106 cfu/fish, respectively.

ANALISIS IN VITRO AKTIVITAS ANTIBAKTERI DAUN SISIK NAGA (Drymoglossum pilosellaoides) TERHADAP BAKTERI Vibrio harveyi DAN Vibrio parahaemolyticus

Penelitian ini mengenai bioaktifitas ekstrak daun sisik naga (Drymoglossum pilosellaoides) terhadap pertumbuhan bakteri Vibrio harveyi dan Vibrio parahaemolyticus. Penelitian ini bertujuan untuk mengetahui bioaktifitas dan efektifitas antibakteri ekstrak daun sisik naga terhadap pertumbuhan bakteri V. harveyi dan V. parahaemolyticus. Pengujian daya hambat dilakukan dengan metode difusi agar menggunakan 5 variasi konsentrasi 100%, 50%, 25%, 12,5% dan 6,25% b/v pada media TSA (Tryptone Soya Agar) dan TCBS (Thiosulfate Citrate Bile Salts Sucrose) yang diinkubasi selama 2x24 jam. Digunakan pula antibiotik berupa chloramphenicol 10-1 (= 30 µg) sebagai kontrol positif, dan sebagai kontrol negatif digunakan akuades. Ekstrak daun sisik naga. mengandung flavonoid, saponin dan tanin yang bersifat antibakteri dan memiliki kemampuan mematikan bakteri uji, dengan efektifitas diameter hambatan V. harveyi 14,8 mm pada konsentrasi 100% b/v, sedangkan bakteri V. parahaemolyticus 11,8 mm pada konsentrasi 50% b/v. Efektifitas daya hambat tertinggi pada konsentrasi 50% terhadap bakteri V. parahaemolitycus yaitu sebesar 45,5%, Sedangkan pada konsentrasi 100% memiliki efektifitas daya hambat sebesar 56,3% terhadap bakteri V. harveyi.

Microbiota of different wine grape berries

The wine grape berries share a complex microbial ecology including filamentous fungi, yeasts and bacteria. The microbiota reveals different physiological characteristics and depends on the grape ripening stage and the availability of nutrients with different effect on wine production. The microbiota of grape berries (n = 12) was isolated and identified in the present study. The samples were collected in September 2018. Grape berries were obtained from Vrbovo vineyard located in Slovakia. The grape berries investigated belonged to Blue Frankish, Cabernet Sauvignon, Chardonnay, Dornfelder, Feteasca regala, Green Veltliner, Irsai Oliver, Mūller Thurgau, Pálava, Pinot Blanc, Rhinriesling and Welschriesling varieties. The microorganisms were cultivated on Malt extract agar (MEA) at 25 °C for five days in aerobically for microscopic filamentous fungi and Tryptone Soya agar (TSA) at 37 °C for 24 – 48 h aerobically for bacteria and yeasts. Total bacterial counts on different wine grape berries ranged from 2.57 ±0.09 in Chardonnay to 4.39 ±0.21 log CFU.g-1 in Pálava. Microscopic filamentous fungi count ranged from 1.18 ±0.03 in Blue Frankish to 2.60 ±0.17 log CFU.g-1 in Welschriesling. MALDI-TOF MS Biotyper mass spectrometry was used for identification of microorganisms (bacteria and yeasts) and microscopic filamentous fungi with manuals. The most identified microscopic fungal species was Alternaria sp., for yeasts Issatchenkia orientalis and Leuconostoc mesenteroides subsp. mesenteroides for bacteria.

Isolation and characterisation of Vibrio alginolyticus lytic bacteriophage φVa-1 from brackishwater clam Meritrix meritrix in India

The Gram negative bacterium Vibrio alginolyticus is generally found in marine and brackishwater systems. A lytic bacteriophage capable of specifically infecting V. alginolyticus was isolated from the brackishwater clam (Meretrix meretrix) using agar overlay technique. The phage produced plaques 3 mm in dia, which increased to 5 mm overnight on tryptone soya agar (TSA) plates and the optimum temperature and pH was found to be 32°C and 7.5 respectively. The phage was designated as φVa-1 and nucleic acid characterisation confirmed that the phage has double stranded DNA. Transmission electron microscopic observations revealed that the bacteriophage had hexagonal structure with a long contractile tail andthe phage was found to belong to the family Myoviridae.