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Penelusuran dan Isolasi Fungi Tanah Muara Pelabuhan Besuki Serta Skrining Aktivitas Antibakteri Terhadap Pseudomonas Aeruginosa
No full textPenyakit infeksi adalah masalah kesehatan di negara berkembang yang kerap menyebabkan kematian di seleruh dunia termasuk Indonesia yang disebabkan salah satunya oleh bakteri Pseudomonas aeruginosa. Penyakit infeksi oleh bakteri dapat diterapi menggunaan antibotik, namun penggunaan antibiotik yang kurang tepat telah memberikan kontribusi signifikan terhadap munculnya kasus resistensi yang menyebabkan obat kehilangan kemampuan untuk menghambat pertumbuhan bakteri. Resistensi tersebut membuat penemuan alternatif antibiotik baru untuk melawan penyakit infeksi akibat bakteri menjadi sangat diperlukan. Salah satu penemuan antibiotik dapat bersumber dari fungi. Penelitian antibakteri dari fungi masih minim dilakukan salah satunya fungi dari tanah muara. Hal ini menunjukkan penelitian antibakteri dari fungi tanah muara masih sangat diperlukan sebagai bentuk pencarian alternatif antibiotik baru.
Berdasarkan latar belakang tersebut, pada penelitian ini dilakukan penelusuran dan isolasi fungi dari tanah muara Pelabuhan Besuki serta menelusuri aktivitas antibakteri terhadap Pseudomonas aeruginosa. Didapatkan 7 isolat fungi berjenis khamir yang berhasil didapatkan dari sampel tanah muara Pelabuhan Besuki, sampel tersebut kemudian diberi kode IS-PB-A1, IS-PB-A2, IS-PB-A3, IS-PB-T1, IS-PB-T2, IS-PB-B1, IS-PB-B2. Isolat tersebut kemudian diuji antagonis dengan P.aeruginosa. Hasil uji tersebut menunjukkan bahwa 7 isolat berpotensi memiliki aktivitas antibakteri yang ditunjukkan dengan nilai diameter zona hambat bakteri. Isolat kemudian difermentasi dengan metode batch fermentation untuk memperoleh metabolit sekunder fungi. Hasil fermentasi selanjutnya diektraksi untuk memisahkan fungi dari fase air yang tidak diperlukan dalam penelitian.
Ekstrak yang dihasilkan diuji aktivitas antibakterinya menggunakan metode mikrodilusi untuk menentukan persen penghambatan pertumbuhan bakteri P.aeruginosa. Kontrol positif yang digunakan yaitu gentamisin, sedangkan kontrol negatif ekstrak yaitu DMSO 1% dalam media. Berdasarkan hasil uji aktivitas antibakteri sampel dengan kode IS-PB-A2 menunjukkan nilai persen penghambatan tertinggi (84,7 ± 1,4 %) sedangkan nilai persen penghambatan terendah dihasilkan oleh sampel dengan kode IS-PB-T2 (30,5 ± 3,3 %). Pengujian aktivitas antibakteri dalam penelitian ini menunjukkan sampel ekstrak fungi tanah yang diisolasi dari tanah muara Pelabuhan Besuki Situbondo dapat dinyatakan berpotensi sebagai antibakteri, namun belum bisa disimpulkan aktivitasnya karena dibutuhkan penelitian lebih lanjut terkait nilai IC50 dari masing-masing sampe
Penelusuran dan Isolasi Fungi Tanah Muara Pelabuhan Besuki Serta Skrining Aktivitas Antibakteri Terhadap Pseudomonas Aeruginosaattcc 27853
No full textPenyakit infeksi merupakan salah satu penyebab utama kematian di dunia. Terapi infeksi bakteri dengan antibiotik yang tidak tepat penggunaannya dapat menyebabkan resistensi. Penemuan antibiotik baru dapat berasal dari bahan alam, salah satunya fungi. Penelitian ini bertujuan untuk mengetahui aktivitas antibakteri ekstrak etil asetat hasil fermentasi fungi khamir tanah muara terhadap Pseudomonas aeruginosa.Isolasi fungi tanah dilakukan menggunakan media Potato dextrose Agar (PDA) dilarutkan dalam air laut. Proses tersebut menghasilkan 7 isolat fungi kemudian disebut IS-PB-A1, IS-PB-A2, IS-PB-A3, ISPB-T1, IS-PB-T2, IS-PB-B1, IS-PB-B2. Semua isolat fungi memiliki potensi dalam menghambat pertumbuhan bakteri dengan uji antagonis. Pengujian aktivitas antibakteri dilanjutkan menggunakan metode mikrodilusi. Aktivitas antibakteri disajikan dalam bentuk persen penghambatan. Hasil uji antibakteri dari tujuh ekstrak konsentrasi 100 µg/mL menunjukkan persen penghambatan tertinggi dari kode IS-PB-A2 (84,7 ± 1,4%) dan terendah dari kode IS-PB-T2 (30,5 ± 3,3 %). Senyawa yang berperan menghambat pertumbuhan bakteri dalam penelitian ini belum bisa dipastikan sehingga diperlukan penelitian lebih lanjut
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
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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