THE EFFECT OF INHIBITOR TOWARD ENZYME ACTIVITY

Enzymes are proteins that catalyze chemical reactions in biological systems in terms of the biocatalyze which has the nature of catalysts in general are involved react, but at the end of the reaction will be retrieved in its original form. Inhibitor is a compound that can inhibit or decrease the rate of reaction catalyzed by the enzyme. Enzyme inhibitors itself are divided into two kinds namely reversible and irreversible inhibitor. The aims of this experiment was to determine the effect of inhibitors on enzyme activity seen from the value of V_max and K_M reaction without inhibitor and with inhibitor. The method used was quantitative analysis. In this experiment were used sodium succinate as a substrate and sodium citrate as a inhibitor. The Na-citrate was inhibited reaction catalyzed by the enzyme succinate dehydrogenase. The value of K_M  in reaction without inhibitor is 6.754 x 10^-2 M, while in reaction with inhibitor is 0.4 M. So, it can be conclude that addition of inhibitor concentration cause increasing in K_M value but had no effect on the value of V_max..

Keywords: Enzyme, Succinate dehydrogenase, Competitive inhibitor

THE KINETIC OF ENZYMATIC REACTION

Enzymes are proteins that catalyze chemical reactions in biological systems in terms of the biocatalyze which has the nature of catalysts in general are involved react, but at the end of the reaction will be retrieved in its original form. The aims of this experiment was to determine of the value of V_max and K_M using the relationship curve between the enzymatic reaction rate and substrate concentration.  The method used was quantitative analysis. Then, the instrument used was Spectronic 20⁺. In this experiment were used five test tubes for each 20 minutes and 0 minute of incubation. In this case, the substrate used was casein and the enzyme used was trypsin. The kinetics of enzyme reactions can be determined by calculating the value of K_M and V_max. The value of V_max and K_M are determined by using the relationship curve between the rates of enzymatic reaction with substrate concentration The result of this experiment is the value of K_M and V_max for the enzymatic reaction with the enzyme trypsin and casein substrate with t = 0 minute and t = 20 minutes were 0.424 mg/mL and 0.518 mmole/minutes. 
Keywords: Enzyme, Anson method, Lineweaver-Burk plot

DETERMINATION OF PROTEIN CONTENT IN EGG ALBUMIN SOLUTION THROUGH LOWRY METHOD

Egg albumin is one sources of protein. Determination of the concentration of protein is a process routinely used in chemical analysis. One purpose of determining the concentration of protein is to know the nutritional value of a food ingredient. There are several methods to determine the protein concentration, such as the Biuret method, Lowry method, and so forth. The objectives of this experiment was to determine the protein content in egg albumin solution through Lowry method.  The method used in this experiment was quantitative analysis. The reagent used was Biuret reagent and Folin-Ciocalteu reagent. Folin-Ciocalteu reagent can detect tyrosine residues because it can  reduce fosfotungstat and forfomolibdat becomes tungstate and molybdenum which has blue color. Biuret reagent also lead the reduction reaction. In determining the protein content of sample, it beginning from making the calibration curve between concentration and absorbance and it got the linier formula y= 0.0461 x + 0.0441 with R = 0.9614. Based on the experiment result, it can be concluded that the content of protein in sample of egg albumin solution is 0.352 mg/mL (in 100 times dilution). Therefore, the initial concentration of the sample is 35.2 mg/mL.

Keywords: Egg albumin, Lowy method, Follin-Ciocalteu reagent, Biuret reagent

THE TEST OF PROTEIN IN EGG ALBUMIN SOLUTION

Proteins are polymers of amino acids that linked through a peptide bond. Egg albumin is one of the main sources of protein. The objectives of this experiment were (1) to identify protein derived from egg by utilizing a unique bond in the protein which is peptide bond by several protein tests, and (2) to determine the effect of physical changes caused by the changing of  temperature, pH and chemical substances on the structure protein The method used in this experiment was qualitative method. Based on the result obatined, it can be concluded egg albumin solution contains protein and can be identified by several tests. The results were Biuret test showed positive results, namely a purple solution due to the formation of complex Cu²⁺; precipitation of proteins by metal HgCl₂ and Pb(CH₃COO)₂ produced white precipitate;  precipitation by salt (NH₄)₂SO₄ which produced white precipitate and its precipitate were positive in Millon test (red precipitate) and soluble in water, and then the filtrate was positive with the Biuret test (bluish solution); precipitation of proteins by alcohol produced white precipitate in the acid and buffer conditions; protein coagulation produced  white precipitate and positive in Millon test (red precipitate); and protein denaturation produced white precipitate in acid and buffer conditions. From the test that has been done,  egg contains the amino acid tyrosine, as shown on the Millon test that is specific to this amino acid. Then, the structure of protein was influenced by temperature, chemical substances and pH.

Keywords: Amino acids, Egg albumin, Biuret test, Protein precipitation by metal, Protein precipitation by salt, Coagulation test, Protein precipitation by alcohol, Protein denaturation 

IDENTIFICATION OF AMINO ACID IN UNKNOWN SAMPLE THROUGH PAPER CHROMATOGRAPHY TECHNIQUE

Chromatography is introduced as a technique for separating and/or identifying the components in a mixture. One type of chromatography is a paper chromatography, which has the stationary phase and mobile phase that the liquid which is not mixed with each other. By using paper chromatography, it can be determined amino acid content that is existed in the sample by comparing the value of Rf sample components with the value of standard Rf. On paper chromatography experiment was used a mixture of n-butanol, aquades, and glacial acetic acid as the eluent. In this experiment, it was carried out a qualitative analysis of a solution containing several amino acids, which aims to determine the ratio of the distribution coefficient (R_f) from a variety of amino acids, especially glycine, cysteine, phenylalanine and tryptophan as well as determination on unknown sample by paper chromatography in ascending technique. Based on the experiment, the R_f value of glycine, cysteine, trypthopan, phenylalanine, unknown A, and B solutions namely 0.186; 0.197; 0.569; 0.605; 0.174; 0.232; 0.174; 0.558 and 0.581. Then, the amino acids that contained in the unknown A were glycine and cysteine. While, the amino acids that contained in the unknown B were glycine, tryptophan and phenylalanine.

Keywords: Amino acid, Paper chromatography

HYDROLYSIS OF GELATIN BY PROTEASE ENZYME THROUGH FORMAL TITRATION METHOD

Proteins are organic compounds consisting of one or more amino acids. If the protein is hydrolyzed, it will be produced amino acid. One way that can be used to obtain the amino acid is hydrolysis of protein. The aims of the experiment were (1) to hydrolyze protein with protease enzyme, and (2) to make curve between NaOH(mL) vs time (minute) as well as curve of nitrogen amino acid mass (mg) vs time (minute) by formal titration method. This experiment used quantitative method. In this experiment, amino acids obtained from hydrolysis of gelatin solution by the enzyme trypsin (protease enzyme) was titrated by NaOH solution. It should be noted also the condition of trypsin and gelatin solution were maintained by incubated at 38° C and pH=8 for reactions run optimally. The result of this experiment was protein hydrolysis of gelatin can be done by using protease enzyme. Then, curve between volume of NaOH that was needed in titration and time that was used by gelatin solution to react with protease enzyme was directly proportional. After that, curve between the mass (mg) nitrogen of amino acid that was produced and time that was used by gelatin solution to react with protease enzyme was directly proportional.

Keywords: Amino acid, Formal titration, Protease enzyme

IDENTIFICATION OF AMINO ACID IN EGG ALBUMIN, UNKNOWN B AND D SOLUTIONS THROUGH MILLON, HOPKINS-COLE, NINHIDRIN, PbS, AND NITROPRUSIDE TESTS

Amino acid is a compound that is very important as a constituent unit of protein. Total amino acids exist in nature, only 20 types of amino acids contained in protein. The purposes of this experiment are to identify (1) the types of amino acids contained in protein solution (egg albumin) through Millon, Hopkins-Cole, Ninhydrin, PbS and Nitropruside test, and (2) the types of amino acids contained in the unknown sample through the amino acid test. The method used in this experiment was qualitative analysis. The result of this experiment were, first, egg albumin solution is positive in Millon, Hopkins-Cole, Ninhydrin, and PbS tests. It means that in egg albumin contains tyrosin, tryptophan, α-amino acid and sulfur. Second, unknown B solution is positive in Millon test, in which it contains hydroxyphenyl compound. Besides that, unknown B solution is also positive in Ninhydrin test in which it contains α-amino acids and peptides having free α-amino group. While, unknown D solution is positive in Nitropruside test, thus it contained –SH group. So, it can be concluded that egg albumin contains tyrosin, tryptophan, α-amino acid and sulfur; unknown B is tyrosine solution; and unknown D is cysteine solution.

Keywords: Amino acids, Egg albumin, Millon test, Hopkins-Cole test, Ninhydrine test, PbS test, Nitropruside test.

Desain Baju VISCUP

ini desain baju VISCUP, mohon kerjasamanya yaa untuk membeli biar sukses acara viscupnya :D

Suksesi Korti Kelas Semester 2 A-Class Chemistry Education Department

Suksesi atau yang lebih dikenal di masyarakat umum adalah pemilu. Nah disini beda, jika kita berada di lingkungan mahasiswa, istilah suksesi-lah yang lebih sering digunakan. Suksesi Korti kelas baru untuk semester 2 ini dilaksanakan tanggal 28 Januari 2013 di Lab. Audio PUSKOM UNDIKSHA. Suksesi ini dipimpin langsung oleh Ketua Presidium Sidang yang sebelumnya menjabat sebagai Korti kelas semester 1, yaitu Rahayu. Nah disini, karena persaingan masing-masing calon cukup kuat, akhirnya didapatkan titik temu untuk melakukan voting. Hasil Voting terhadap 6 calon perangkat yang nantinya akan menjabat sebagai Korti, Sekretaris dan Bendahara adalah sebagai berikut :

Partikel Tuhan ? hems partikel apa ini ya?

hemms, guys, pastinya partikel Tuhan sedang boomingnya saat ini, ini adalah penemuan terbaru di bidang ilmu fisika. jadi ini salah satu kutipan dari http://www.tempo.co/read/news/2012/07/06/095415223/Apa-dan-Kenapa-Partikel-Tuhan

Penemuan partikel Tuhan pada Selasa, 3 Juli 2012, menjadi tonggak sejarah perkembangan fisika partikel. Dampak bagi orang awam adalah tidak ada lagi penjelasan sederhana tentang komposisi atom. Sebuah atom selama ini dikenal memiliki komposisi yang terdiri dari proton (bermuatan positif), elektron (bermuatan negatif), dan neutron (bermuatan netral). Tapi kini ada lagi tambahan Higgs-Boson.

Peraturan ya.. Hanya untuk Dilanggar Saja

Kata-kata diatas sangatlah sesuai dengan kenyataan yang ada di masyarakat. Mengapa tidak? Hal ini dapat dibuktikan, jika kita ingin memastikannya dan peduli terhadap lingkungan di sekitar kita.

Gambar diatas saya dapatkan sendiri karena pengalaman saya. Awalnya dari hari kehari di tempat itu memang penuh sesak oleh parkirkan sepeda motor dan karena saya tidak pernah berhenti disana jadi saya tidak tahu ada papan larangan itu. Suatu ketika saya hendak ikut juga parkir dan saya tak sengaja melihat papan larangan parkir bagi pengguna sepeda beroda dua. Dan alhasil saya juga bingung hendak parkir dimana sekarang karena saat itu didekat saya memang tak ada sepeda motor yang parkir. Setelah saya telaah dan saya lihat langsung beberapa jam kemudian ternyata lahan parkir tadi penuh dengan deretan sepeda motor. Ternyata, tadi tidak ada sepeda motor yang parkir bukannya karena larangan itu baru dipasang tetapi karena saya sudah lebih dahulu sampai dan di waktu pagi-pagi buta.

Mengajar atau Berdagang

Mungkin hal ini idak bisa ditemukan di semua sekolah tapi hal ini jika kita telusuri ada di beberapa sekolah yang tidak terkena sorot public atau masyarakat yang hanya diam membisu melihat sutu kejadian ini.

Di suatu sekolah, entah ini hanya buah bibir para orang tua semata atau memang keadaan nyata. Ternyata dalam suatu sekolah ada saja masih kegiatan berjualan yang dilakukan oleh oknum-oknum guru, yang merupakan panutan dan pengajar di sekolah. Hal ini dilakukan hanyalah untuk mencari keuntungan semata. Maksud dari kejadian yang diperbincangkan dari tadi adalah masalah berjualan makanan yang di handel langsung oleh guru tersebut bukannya menyuruh orang lain yang seharusnya bertugas berjualan di kantin tapi gurulah yang secara bergantian berjualan di kantin sekolah.

Resep : Cara alami menghitamkan rambut :)

          caranya sih agak konvensional, tapi guys cocok untuk dicoba daripada menggunakan berbagai macam shampoo yg banyak mengandung bahan kimia yang sebvenarnya kita para masyarakat awam belum mengetahui secara pasti apakah bahan kimia penyusun shampoo yang kita beli itu berbahaya atau tidak bagi kulit kepala dan rambut kita

1. Siapkan beberapa ikat merang padi yang sudah kering, untuk jumlahnnya tergantung dari rambut yang ingin kita rawat supaya lebih hitam dan berkilau.
2. Bakar merang padi yang sudah kita siapkan tersebut, sebaiknya merang yang kita bakar didalam wadah, supaya lebih mudah, dan terbuat dari tanah agar tidak ikut terbakar
3. Merang padi yang sudah kita bakar dan menjadi abu tersebut, kita tambahkan air, sampai terendam semua, sambil diaduk-aduk supaya rata

hems, ini cerita saat itu

Hari ini tepatnya tanggal 20 Januari, aku sangat merasa terpuruk. Entah perasan itu datnganya darimana, seperti layaknya peribahasa sudah jatuh tertimpa tangga. Awalnya saat ini aku mengikuti lomba dan saat perlombaan akan dimulai para hadirin termasuk undangan duduk aku tanpa sengaja melihat seorang lelaki dan memang sangat mirip dengannya. Hanya saja yang kulihat barusan tidak memakai kacamata. Sungguh benar-benar mirip dan membuatku kembali mengingat masa-masa yang dulu. Hems.. sungguh ingin kulupakan tetapi hal itu tak bisa dan diberikan cobaan seperti ini -.-

Okey, setelah itu aku tak lagi melihatnya, entah dia pergi kearah mana dan duduk dimana aku tak pikirkan lagi. Lalu saat itu aku asyik mendengarkan pembukaan. Saat perlombaan, sudah kulakukan semuanya sesuai dengan kemampuanku dan kulakukan dengan senyum saja semuanya. Dan aku yakin yang telah aku lakukan ini memang sesuai dengan ketentuan yang diberitahukan sebelumnya. Walaupun tadinya aku agak terkejut melihat lawan-lawanku yang lain yang sangat berbeda sekali penampilannya denganku.

Saat sebelum pengumuman kejuaraan diumumkan hatiku sangat kacau dan pikiranku sangat berkecamuk karena pikiranku sudah mengatakan bahwa aku tidaklah akan dapat memenangkan kejuaraan itu. Dan alhasil aku tak mendapatkan nya. Dan saat itu juga aku merasa sangat malu karena semua teman-temanku mendapatkan juara, benar-benar saat itu aku ingin menangis tetapi tak kulakukan dan kulakukan di rumah. Sungguh saat itu kucurahkan semua air mataku karena tak sanggup menerima kekalahan yang tak etis.