Judul: Degradasi in vitro asam fitat rumput dan legum oleh konsorsium bakteri rumen pencerna serat asal kerbau
Abstrak: Phytic acid is the major storage of phosphorus in the seeds of legume and cereal. It is degraded by ruminal bacteria. However the ability of bacteria isolates in degrading nutrients and phytic acid is not clear. The objective of this study was to evaluate the ability of sellulolytic bacteria consortium isolated from rumen buffalo to degrade phytic acid and digest dry matter, as well as organic matter. The first trial evaluated the ability of sellulolytic bacteria consortiom in degrading phytic acid. The consortium of 6 rumen bacteria isolates was incubated anaerobically in media containing pollard, legume and grass for 3, 6 and 12 hours. Phytic acid content contained in the media was determined before and after fermentation. Data were analyzed according to simple statistic. The second trial was designed to evaluate the in vitro fermentability of legumes and grasses. The results suggested that phytic acid was partly degraded by the consortium of rumen bacteria. Degradation of phytic acid was influenced by type of plant and fermentation period. There was no correlation between phytic acid degradation and concentration of VFA, NH3, dry matter and organic matter digestibility. It was concluded that consortium of rumen bacteria was capable in degrading phytic acid contained in grasses and concentrates, but its degradation was not affected by the protein degradation and fermentation of carbohyd
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Judul: Efektivitas Isolat Bakteri Rumen Kerbau Pencerna Serat dalam Fermentasi Hijauan Leguminosa dan Pemanfaatan Urea in vitro
Abstrak: Ruminants have ability to digest fiber component of feed due to the presence of cellulolitic bacteria in their rumen that secrete cellulase. Other bacteria have capability to digest protein by secreting protease and utilize non protein nitrogen. Fiber-digesting bacteria isolated from rumen of buffalo have not been confirmed in their ability to digest protein rich feed and utilize protein. This study aimed to evaluate the ability of fiber-digesting bacteria isolates in digesting leguminous herbage, degrading protein and utilizing non protein nitrogen. The first study was to compare the fermentability and coeficient digestibility of Calliandra callotyrsus, Leucaena leucocephala, Indigofera sp. and Gliricidia sepium by using bacteria in fresh rumen fluid and fiber-digesting bacteria isolates. The second study aimed to evaluate the ability of buffalo rumen bacterial isolates in the use of urea. Corn and cassava waste were used as carbohydrate sources with addition of urea as non protein nitrogen at level of 3%, 4,5%, and 6%. The first study showed that source of bacteria had no different effect on VFA concentration, and the coeficient digestibility of dry and organic matter of the herbage. The NH3 levels in the treatment of bacterial isolates was higher than that of fresh rumen fluid (P <0.05). The buffalo rumen bacterial isolates have the ability to degrade proteins and also showed that Indigofera sp., and Gliricidia sepium protein more susceptible to degradation than other legumes. The levels of NH3 in fermentaion media of feed added urea to 6% was in normal level. It was concluded that fiber-digesting rumen bacteria isolates were able to digest leguminous herbage and utilize the protein component of legume and capable of utilizing urea up to 6% in starchy feed.
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Judul: Penggunaan Teorema Homeomorphy 2-Manifold dan Teorema Euler Poincare pada Torus 𝑇�� dan Simplicial Complex 𝐾��
Abstrak: Two dimensional topological spaces are said to be homeomorphic if they have the same topological invariant, where one of topological invariant used is an Euler characteristic. Homeomorphy 2-Manifold’s Theorem and Euler Poincare’s Theorem are used to distinguish two topological spaces. Homeomorphy 2-Manifold’s Theorem uses Euler characteristic to identify two dimensional topological spaces. Euler Poincare’s Theorem is an alternative way to find Euler characteristic with Betti number, which is topological invariant as well. The objective of this paper is to investigate the homeomorphism of torus 𝑇����� and simplicial complex 𝐾�����. Topological space torus and simplicial complex 𝐾����� have the same Euler characteristic, which is two. Based on Homeomorphy 2-Manifold’s Theorem topological space torus 𝑇����� and simplicial complex 𝐾����� is homeomorphic.
Keyword: simplicial, torus, Euler, homeomorphism, topology