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Bahan ajar mikrobiologi
No full textbuku ini disusun untuk membantu para mahasiswa s-1 di Fakultas Biologi UGM dalam memahami konsep dasar teoritis mengenai mikrobiologi dasar yang hingga saat ini buku ajar dan pustaka mengenai mikrobioologi dalam bahasa indoensia masih sangat terbatas
production and characterization of biosurfactants produced by pseudomonas aeruginosa b031 isolated from a hydrocarbon phytoremediation field
No full textThe biosurfactants are used by several industrial sectors such as petroleum, agriculture, food production, chemistry, cosmetics, and pharmaceuticals. Because of their hydrophobic and hydrophilic moieties, they have potency to reduce surface tension, interfacial tension between water-hydrocarbon systems, and low micelle concentration. Their characteristics strongly depend on the producer strain as well as on the medium composition, such as carbon and nitrogen sources. This study was conducted to investigate the influence of different sources of carbon (n-hexadecane, glycerol and glucose) and nitrogen (urea, NH4Cl and NaNO3) for the production of biosurfactants by a new strain of Pseudomonas aeruginosa B031 isolated from a rhizosphere of Paraserianthes falcataria L. Nielsen, a hardwood plant species at a phytoremediation field. The biosurfactant characteristics of the strain were evaluated, particularly its surface-active properties and potential to remove hydrocarbon. Glycerol was found to be the optimum carbon source, with rhamnose concentration, emulsification index, and critical micelle concentration (CMC) of 718 mg/L, 37%, and 35 mN/m, respectively. NaNO3 was observed as the optimum nitrogen source, with rhamnose concentration, emulsification index, and CMC of 290 mg/L, 30%, and 24 mN/m, respectively. These biosurfactants efficiently reduced surface tension of culture broth from 42 mN/m to 31 mN/m for the glycerol treatment and from 37 mN/m to 24 mN/m for the sodium nitrate treatment. The crude biosurfactants from the glycerol and sodium nitrate treatments also removed 87.5% and 84%, respectively, of crude oil from sand. These rates were higher than those of the chemical surfactants (SDS and Triton X-100). These findings indicate that the biosurfactants produced by the strain from both glycerol and NaNO3 treatments can efficiently decrease the interfacial tension of culture broth dilution and have a high emulsion index, thus hold promise in hydrocarbon bioremediation application
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Pyrolusite Bioleaching by an Indigenous <i>Acidithiobacillus</i> sp KL3 Isolated from an Indonesian Sulfurous River Sediment
Get PDFThe manganese bioleaching process of pyrolusite from Kliripan, Indonesia using Acidithiobacillus sp KL3 was investigated. The influence pulp densities of pyrolusite (0.01, 0.02, 0.03 and 0.05 g/cm3) on the bioleaching processes were studied for 16 days. The reduction on pH values, the increasing of oxidation-reduction potential (ORP), sulfate and manganese concentration were analyzed. The manganese bioleaching mechanism of pyrolusite by the strain was monitored using Scanning Electron Microscope-Energy Dispersive-X-ray Spectroscopy (SEM-EDX). The results indicated that 0.02 g/cm3 of pyrolusite was considered to be the optimal pulp density for manganese bioleaching process. During this process, pH values decreased, furthermore resulted in increasing of ORP, the concentration of sulfate and manganese. SEM-EDX analysis clearly showed the evidence of directly bacterial cell attachment into the surface of pyrolusite. Extracellular polymeric substances (EPSs) were further founded on that surface. Sulfur elemental was oxidized by the strain which was then confirmed of resulting in solubilized manganese
Removal of Sulphate and Manganese on Synthetic Wastewater in Sulphate Reducing Bioreactor Using Indonesian Natural Zeolite
Get PDFThe present research was conducted to investigate sulphate and manganese removal from synthetic wastewater. The continuous laboratory scale of down-flow fluidized-bed reactor (DFBR) using sulphate reducing bacteria (SRB) consortium and Indonesian natural zeolite as a bacterial support material was designed. At 9 days operation, maximum sulphate and manganese removal was observed to be 23% and 15.4%, respectively. The pH values were also changed to neutral. The population of SRB increased which effect on the raising of their activity for removing sulphate and manganese. Using the scanning electronic microscopy (SEM), it was observed that natural zeolite possesses excellent physical characteristics as a bacterial support material in DFBR. The imaging SEM result of SRB consortium on zeolite surface clearly showed the developed SRB biofilm on that particle. Analysis result of EDX confirmed that manganese was precipitated as manganese–sulfides
Performance and bacterial composition of anodic biofilms in microbial fuel cell using dairy wastewater
No full textThe Numerical Phenetic of Taxonomy Vibrio in Shellfish (Meretrix meretrix) at Edu-Tourism Mangrove Cengkrong Beach Trenggalek
Get PDFHighlight
• Identify the Vibrio bacteria
• Diversity of shellfish Vibrio bacteria (Meretrix Meretrix)
• Relationship similarity of Vibrio bacteria with MVSP 3.1 Program produces Dendogram
Abstract
Meretrix meretrix is one type of shellfish that is potential, and economic value, which high animal protein content as well as seafood that is widely consumed in Indonesia. This study aims to determine the diversity and similarity of Vibrio in M. meretrix at eduwisata mangrove Cengkrong Beach, Trenggalek. Isolation and identification of Vibrio was conducted by using the media TCBSA (Thiosulfate Citrate Bile Salt Sucrose Agar) streat plate through morphological observation, physiological and biochemical tests based Bergey's Manual of Systematic Bacteriology conducted in the laboratory of Microbiology Faculty of Biology, Universitas Gajah Mada. Data analysis was performed using the MVSP (Multivariate Statistical Package) 3.1 in the form of a dendrogram showing the similarity relationship Vibrio bacteria. The results of the identification of Vibrio bacteria in M. Meretrix are V. herveyi, V. parahemolyticus, V. nereis and V. proteolyticus. V. herveyi has similarities with V. parahemolyticus 66% and 62% with V. proteolyticus while with V. nereis bacterium 54%
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