111 research outputs found
Keragaman Genetik Plasma Nutfah Rambutan di Indonesia Berdasarkan Karakter Morfologi
Rambutan merupakan tanaman menyerbuk silang sehingga secara alami memiliki keragaman tinggi. Penelitian bertujuan mempelajari kemiripan genetik dan pengelompokan aksesi plasma nutfah rambutan (Nephelium lappaceum) dan kapulasan (Nephelium ramboutan-ake) di Indonesia berdasarkan karakteristik morfologi. Penelitian dilakukan di (1) Kebun Percobaan (KP) Aripan Balai Penelitian Tanaman Buah Tropika, (2) KP Subang Balai Penelitian Tanaman Buah Tropika, (3) KP Cipaku Balai Pengkajian Teknologi Pertanian Jawa Barat, dan (4) Kabupaten Limapuluh Kota (Sumatera Barat), pada bulan Juni 2013 sampai Februari 2014. Karakterisasi sifat morfologi dilakukan terhadap 29 aksesi rambutan dan empat aksesi kapulasan mengacu pada descriptor for rambutan yang diterbitkan IPGRI. Perhitungan koefisien ketidakmiripan antaraksesi dilakukan dengan metode Gower. Analisis nominal logistic biplot dilakukan untuk melihat sifat penciri dari suatu kumpulan aksesi. Analisis keragaman genetik dapat membedakan kelompok rambutan dan kapulasan dengan koefisien ketidakmiripan rerata sekitar 55%. Berdasarkan kerapatan tandan, rambutan dapat dikelompokkan menjadi lima kelompok, yaitu aksesi yang memiliki tandan sangat jarang, jarang, sedang, rapat, dan sangat rapat. Aksesi dengan tandan rapat sampai sangat rapat antara lain aksesi Gendut Kair, Tangkue, dan Aceh Gendut, sedangkan semua aksesi kapulasan memiliki tandan yang sangat jarang. Berdasarkan ketebalan kulit buah, semua aksesi rambutan memiliki ketebalan kulit sedang sampai tebal, sedangkan aksesi Sibabat diketahui memiliki kulit yang sangat tebal
Technique for preparation of anaerobic microbes: Rodshaped cellulolytic bacteria
Preparation of anaerobic-rod cellulolytic bacteria with coating technique has been conducted. Steps of the processes involved were cultivation, coating, evaporation, and drying. Coating agent used was Gum Arabic, and drying techniquesconducted were freeze drying and sun drying. pH of culture media was firstly optimized to obtain the maximal population ofbacteria. Both coated and uncoated preparates were subjected to drying. Morphological and Gram type identifications showed that uncoated preparate dried with freeze drying is not contaminated (ie. all bacteria are rod shape with Gram-negative type) while the one dried with sun drying is not morphologically pure (ie. containing of both rod and coccus shapes with Gram negative and positive). The coated preparates dried by both freeze and sun drying, were not contaminated (ie. all are rods with Gram-negative). The coating and drying processes decreased viability of preparates significantly. However, the decreasing of viability of coated preparate are lower than uncoated preparate (ie. 89 vs. 97%). Total count of bacteria in sun-drying coated preparate are higher (P0.05) than the uncoated preparate (ie. 3.38 x 1010 vs. 1.97 x 1010 colony/g DM). Activity of sun-drying coated preparate to digest elephant grass and rice straw was higher (P0.01) than the sun-drying uncoated preparate with the in vitro DMD values were 42.7 vs. 35.5% for elephant grass substrate and 29.3 vs. 24.6% for rice straw substrate. Therefore, it is concluded that coating technique has a positive effects on the preparation of rumen bacteria. Key words : Anaerobic bacteria, coating, dryin
Co-limitation towards lower latitudes shapes global forest diversity gradients
The latitudinal diversity gradient (LDG) is one of the most recognized global patterns of species richness exhibited across a wide range of taxa. Numerous hypotheses have been proposed in the past two centuries to explain LDG, but rigorous tests of the drivers of LDGs have been limited by a lack of high-quality global species richness data. Here we produce a high-resolution (0.025° × 0.025°) map of local tree species richness using a global forest inventory database with individual tree information and local biophysical characteristics from ~1.3 million sample plots. We then quantify drivers of local tree species richness patterns across latitudes. Generally, annual mean temperature was a dominant predictor of tree species richness, which is most consistent with the metabolic theory of biodiversity (MTB). However, MTB underestimated LDG in the tropics, where high species richness was also moderated by topographic, soil and anthropogenic factors operating at local scales. Given that local landscape variables operate synergistically with bioclimatic factors in shaping the global LDG pattern, we suggest that MTB be extended to account for co-limitation by subordinate drivers
Co-limitation towards lower latitudes shapes global forest diversity gradients
The latitudinal diversity gradient (LDG) is one of the most recognized global patterns of species richness exhibited across a wide range of taxa. Numerous hypotheses have been proposed in the past two centuries to explain LDG, but rigorous tests of the drivers of LDGs have been limited by a lack of high-quality global species richness data. Here we produce a high-resolution (0.025° × 0.025°) map of local tree species richness using a global forest inventory database with individual tree information and local biophysical characteristics from ~1.3 million sample plots. We then quantify drivers of local tree species richness patterns across latitudes. Generally, annual mean temperature was a dominant predictor of tree species richness, which is most consistent with the metabolic theory of biodiversity (MTB). However, MTB underestimated LDG in the tropics, where high species richness was also moderated by topographic, soil and anthropogenic factors operating at local scales. Given that local landscape variables operate synergistically with bioclimatic factors in shaping the global LDG pattern, we suggest that MTB be extended to account for co-limitation by subordinate drivers
Over-the-Counter Monocyclic Non-Steroidal Anti-Inflammatory Drugs in Environment—Sources, Risks, Biodegradation
Recently, the increased use of monocyclic
non-steroidal anti-inflammatory drugs has resulted in
their presence in the environment. This may have
potential negative effects on living organisms. The
biotransformation mechanisms of monocyclic nonsteroidal
anti-inflammatory drugs in the human body
and in other mammals occur by hydroxylation and
conjugation with glycine or glucuronic acid.
Biotransformation/biodegradation of monocyclic
non-steroidal anti-inflammatory drugs in the environment
may be caused by fungal or bacterial microorganisms.
Salicylic acid derivatives are degraded by
catechol or gentisate as intermediates which are
cleaved by dioxygenases. The key intermediate of
the paracetamol degradation pathways is hydroquinone.
Sometimes, after hydrolysis of this drug, 4-
aminophenol is formed, which is a dead-end metabolite.
Ibuprofen is metabolized by hydroxylation or
activation with CoA, resulting in the formation of
isobutylocatechol. The aim of this work is to attempt
to summarize the knowledge about environmental risk
connected with the presence of over-the-counter antiinflammatory
drugs, their sources and the biotransformation
and/or biodegradation pathways of these
drugs
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