Defi Natalia - Academia.edu (original) (raw)

Papers by Defi Natalia

Cassava is a fruit of the plant tubers that grow in the soil. Cassava has a hard texture of the m... more Cassava is a fruit of the plant tubers that grow in the soil. Cassava has a hard texture of the meat.Cassava also be used as a companion in several dishes such as fried foods, spinach village, a variety of snacks, chips and other dishes.The chips are snacks that are popular with the public. The chips are classified as types of food craker foods that are dry and crisp with a high fat content.Cassava cutting machine is a tool to cut cassava into thin sheets with a thickness of ± 1 to 2 mm. Not only that, the machine also can produce pieces with the same thickness, and the cutting time becomes fast.The design is the beginning of a series of activities in the process of making the product. The perancanagna stage made important decisions that affect other activities follow. Thus, before a product is made first made the design process that will produce a drawing or a simple picture of product to be made

IOP Conference Series: Earth and Environmental Science, 2021

This study aims to determine the effects of indigenous Alcaligenes sp. LS2T and Arthrobacter sp. ... more This study aims to determine the effects of indigenous Alcaligenes sp. LS2T and Arthrobacter sp. LM1KK in the composting of rabbit feces. This study consists of 3 treatments (commercial starter as control, Alcaligenes sp. LS2T, and Arthrobacter sp. LM1KK) in triplicate replication. Starter growth profile, emitted ammonia concentration, physical qualities of compost, and the compost’s chemical quality were observed in this study. The data was analyzed using a randomized design (One-way ANOVA). Alcaligenes sp. LS2T has a significant ability to reduce ammonia emission compare to Arthrobacter sp. LM1KK and commercial starter. The best result of the chemical quality of compost was done by Arthrobacter sp. LM1KK with water content observed 28.78%, organic matter was 13.75%, 7.97% of C-organic, P total observed 1.38%, K determined 2.52%. Furthermore, the N value was 0.65%, and C/N Ratio observed 14.97%. As a conclusion, Alcaligenes sp. LS2T and Arthrobacter sp. LM1KK had the potency as sam...

IOP Conference Series: Materials Science and Engineering

Inulin hydrolysis thermophilic and thermotolerant bacteria are potential sources of inulin hydrol... more Inulin hydrolysis thermophilic and thermotolerant bacteria are potential sources of inulin hydrolysis enzymes. Partial gene that encodes inulin hydrolysis enzymes had been isolated from Bacillus subtilis using polymerase chain reaction (PCR) method with the DPE.slFandDPE.eR degenerative primers. The partial gene was cloned into pGEM-T Easy vector with E. coli as host cells and analyzed using BLASTx, CrustalW2, and Phyre2 programs. Size of thepartial gene had been found539 bp that encoded 179aminoacid residues of protein fragment. The sequences of protein fragment was more similar to exolevanase than exoinulinase. The protein fragment had conserved motif FSGS, and specific hits GH32 βfructosidase. It had three residues of active site and five residues of substrate binding. The active site on the protein fragment were D (1-WLNDP-5), D (125-FRDPK-129) and E (177-WEC-179). Substrate binding on the protein fragment were ND (1-WLNDP-5), Q (18-FYQY-21), FS (60-FSGS-63) RD (125-FRDPK-129) and E (177-WEC-179).

Journal of Mathematics and Its Applications

Pada karya ilmiah ini, penyebaran influenza dua strain dimodelkan dengan melibatkan tiga variabel... more Pada karya ilmiah ini, penyebaran influenza dua strain dimodelkan dengan melibatkan tiga variabel kontrol yaitu vaksinasi dan pengobatan pada masing-masing strain. Akan ditentukan variabel kontrol optimum sehingga dapat meminimumkan populasi terinfeksi berdasarkan empat skenario pengendalian. Prinsip maksimum Pontryagin diterapkan untuk menurunkan sistem persamaan diferensial sebagai kondisi yang harus dipenuhi variabel-variabel kontrol optimum. Kemudian, metode Runge-Kutta orde empat digunakan untuk menentukan solusi numerik dari masalah kontrol optimum. Pada solusi numerik ditunjukkan bahwa pemberian tiga buah kontrol pada model penyebaran influenza H1N1 dua strain memberikan pengaruh yang baik karena dapat menurunkan populasi individu terinfeksi oleh strain satu dan strain dua sampai 99% serta meningkatkan populasi individu yang telah diobati secara efektif sampai 85% pada bulan ke lima.

$Research paper thumbnail of {"__content__"=>"Molecular Analysis of Encoding Catalase-Peroxidase from Clinical Isolate of Isoniazid-Resistant Mycobacterium tuberculosis.", "i"=>{"__content__"=>"katG"}}$

Journal of medicine and life

Isoniazid (INH) is a drug for the treatment of tuberculosis in patients infected with Mycobacteri... more Isoniazid (INH) is a drug for the treatment of tuberculosis in patients infected with Mycobacterium tuberculosis. The katG enzyme, or catalase-peroxidase, activates the pro-drug INH that is coded by the katG gene in M. tuberculosis. Mutations of the katG gene in M. tuberculosis are a major INH resistance mechanism. The M. tuberculosis clinical isolate R2 showed INH resistance at a high level of 10 µg/mL. However, the molecular basis for the resistance is unclear. The identification of a mutation in the katG gene of the clinical isolate R2 showed four mutations, i.e., C1061T, G1261 A, G1388T, G2161A, which correspond to the amino acid substitutions T354I, G421S, R463L, and V721M, respectively. The mutant katG gene, along with the wild-type were cloned, expressed and purified. The mutant enzyme showed 86.5% of catalase and 45% of peroxidase activities in comparison to the wild type. The substitutions of TI and GS in mutant katG R2 created significant instability in the adduct triad co...

The Ukrainian Biochemical Journal

Mutations in katg gene are often associated with isoniazid (INh) resistance in Mycobacterium tube... more Mutations in katg gene are often associated with isoniazid (INh) resistance in Mycobacterium tuberculosis strain. this research was perfomed to identify the katg mutation in clinical isolate (l8) that is resistant to INH at 1 μg/ml. In addition to characterize the catalase-peroxidase of KatG L8 and perform the ab initio structural study of the protein to get a more complete understanding in drug activation and the resistance mechanism. The katG gene was cloned and expressed in Escherichia coli, then followed by characterization of catalase-peroxidase of KatG. The structure modelling was performed to know a basis of alterations in enzyme activity. a substitution of a713g that correspond to asn238Ser replacement was found in the l8 katG. The Asn238Ser modification leads to a decline in the activity of catalase-peroxidase and INH oxidation of the L8 KatG protein. The catalytic efficiency (K cat /K M) of mutant katg asn238Ser respectively decreases to 41 and 52% for catalase and peroxidase. The mutant KatG asn238Ser also shows a decrease of 62% in INH oxidation if compared to a wild type katg (katgwt). the mutant asn238Ser might cause instability in the substrate binding site of katg, because of removal of a salt bridge connecting the amine group of asn238 to the carbo xyl group of Glu233, which presents in KatGwt. The lost of the salt bridge in the substrate binding site in mutant katg asn238Ser created changes unfavorable for enzyme activities, which in turn emerge as INh resistance in the l8 isolate of M. tuberculosis.

Jurnal Ilmu-Ilmu Peternakan, 2016

This study aimed to determine the level of feed consumption, egg production, feed conversion rati... more This study aimed to determine the level of feed consumption, egg production, feed conversion ratio (FCR), and the income over feed cost (IOFC) of layers at CV. Popular Farm, Kendal, Semarang. The study used 100 laying hens aged 40 weeks with average body weight 1,815 ± 0.12 g (CV = 6.65%). Feed compositions used for this research were corn flour, bran, premix, soy, meat bone meal and given additional sinbiotik). Experiments at-designed with a completely randomized design (CRD) with 4 treatments and 5 replications. There were 20 units and each unit consists of 5 laying hens. Giving sinbiotic given as 0%, 0.5%, 1%, and 1.5% in the feed. Sinbiotik gave effect at level of 0.5-1% (P<0.05) to reduce the number of intake and feed conversion ratio. Best treatment combination with the performance of chicken layer with a level of 0.5% with the results better of income over feed cost.

Biochemical Society transactions, 1995

Benzaldehyde lyase from Pseudomonas fluorescens Biovar I. (BAL, EC 4.1.2.38) is a versatile catal... more Benzaldehyde lyase from Pseudomonas fluorescens Biovar I. (BAL, EC 4.1.2.38) is a versatile catalyst for the organic synthesis of chiral α-hydroxy ketones. To allow rapid and convenient activity assessment of BAL, a new, robust, and easy-to-handle activity assay based on direct spectrophotometry was developed. The carboligation of 2-furaldehyde into αhydroxyketone (R)-2,2'-furoin was used as a model reaction. The development of nonconventional media such as supercritical fluids and organic solvents was investigated for BAL catalysed reactions. In view of the low solubility and stability of many substrates and products and the prospect of downstream processing, supercritical fluids were explored as alternative solvents in view of the residual stability, activity, and selectivity of the enzymes in such media. Water activity and enzyme preparation (pH of the lyophilisate) were the main influence parameters. Activity increased with increasing water activity, but stability decreased. Furthermore, non-carbon dioxide supercritical fluids such as fluoroform, ethane, and sulphur hexafluoride gave better results in view of stability, activity, and enantioselectivity. Furthermore, the use of the organic solvent 2-methyl tetrahydrofuran as a co-solvent increased the activity and stability of BAL. However, as a second phase in an aqueous-organic system, 2-methyl tetrahydrofuran caused rapid deactivation. Therefore, immobilised BAL (polyvinyl alcohol-entrapped BAL) was used for the two-phase system. The poor solubility of the product in n-hexane caused blockage and deactivation of BAL. n-Hexane gave the highest productivity in both the batch and continuous systems, but only within the first hours of the reaction. Meanwhile, cyclopentyl methyl ether gave higher stability and better activity in terms of yield and long-term productivity, relative to the use of n-hexane as the solvent in batch operation. Finally, a mixture of n-hexane and cyclopentyl methyl ether successfully provided a good yield and productivity as a compromise between single solvents. Thank God "Ida Sang Hyang Widhi Waça" for Your Compassion and Mercy. It is a pleasure to thank those who made this thesis possible. First, I owe my deepest gratitude to Dr. Lasse Greiner for excellent supervision and support during my doctoral thesis. He made his support available in a number of ways and always found the time to help me. Second, I would like to show my gratitude to Prof. Marion B. Ansorge-Schumacher for excellent supervision and the time she shared for discussion. Third, I am grateful to Prof. Walter Leitner for the chance given to me to work in this institute with such exceptional research facilities. I am honoured to have had you as supervisors.

Journal of Biotechnology, 2015

Native enzyme and a mutant containing an extra disulphide bridge of recombinant Saccharomycopsis ... more Native enzyme and a mutant containing an extra disulphide bridge of recombinant Saccharomycopsis fibuligera R64 α-amylase, designated as Sfamy01 and Sfamy02, respectively, have successfully been overexpressed in the yeast Pichia pastoris KM71H. The purified α-amylase variants demonstrated starch hydrolysis resulting in a mixture of maltose, maltotriose, and glucose, similar to the wild type enzyme. Introduction of the disulphide bridge shifted the melting temperature (TM) from 54.5 to 56°C and nearly tripled the enzyme half-life time at 65°C. The two variants have similar kcat/KM values. Similarly, inhibition by acarbose was only slightly affected, with the IC50 of Sfamy02 for acarbose being 40±3.4μM, while that of Sfamy01 was 31±3.9μM. On the other hand, the IC50 of Sfamy02 for EDTA was 0.45mM, nearly two times lower than that of Sfamy01 at 0.77mM. These results show that the introduction of a disulphide bridge had little effect on the enzyme activity, but made the enzyme more susceptible to calcium ion extraction. Altogether, the new disulphide bridge improved the enzyme stability without affecting its activity, although minor changes in the active site environment cannot be excluded.

SKRIPSI AKUNTANSI, 2012

... Hendrawinata Eddy & Siddharta; KAP Herman, Dody, Tanumihardja & Rekan; Kap. Iddris &a... more ... Hendrawinata Eddy & Siddharta; KAP Herman, Dody, Tanumihardja & Rekan; Kap. Iddris & Sudiharto; KAP. Jan Ladiman & Rekan; KAP. Kosasih, Nurdiyaman, Tjahyo & Rekan; KAP. Moch. Zainuddin & Sukmadi; KAP. Drs. R Sunaryono, MM; KAP. Riza, Wahono & Rekan; KAP. ...

Reproductive Biomedicine Online, 2008

more common in older women (P < 0.001). Fewer eggs were collected in the same group. Fertilizatio... more more common in older women (P < 0.001). Fewer eggs were collected in the same group. Fertilization and cleavage rates were significantly lower in the older women compared with the younger (P < 0.001). The number of Grade A embryos transferred in women >38 years were significantly lower (P < 0.05). Endometrial thickness was similar in both groups on the day of embryo transfer. Pregnancy rates were significantly higher in the younger group. Wide perivitelline space with debris, abnormal zona pellucida and vacuoles in the oocytes were the abnormalities that were associated with lower pregnancy rates in both groups. These abnormalities were more common in older women. Conclusion: Poor oocyte morphology is associated with poor pregnancy outcome following ICSI. Older women have a higher incidence of poor quality oocytes, especially those with abnormal zona pellucida, wide perivitelline space with debris and vacuoles, which are found to adversely affect the pregnancy rate.

... Natalia, Dian (2009) Komunikasi interpersonal orang tua dengan anak di dalam keluarga inti pe... more ... Natalia, Dian (2009) Komunikasi interpersonal orang tua dengan anak di dalam keluarga inti perkawinan campuran Indonesia - Jerman ... Sebagai hasilnya ternyata komunikasi interpersonalibu dengan anak lebih dominan daripada komunikasi interpersonal ayah dengan anak ...

Journal of Fluorine …, 2008

Trifluoroethoxylation of hexafluoropropene with 2, 2, 2-trifluoroethanol (TFE) were conducted usi... more Trifluoroethoxylation of hexafluoropropene with 2, 2, 2-trifluoroethanol (TFE) were conducted using an alkali metal fluoride catalyst to produce CF3CHFCF2OCH2CF3. KF exhibited the highest yield and selectivity of CF3CHFCF2OCH2CF3, whereas LiF and ...

Journal of Plant …

The aim of this work was the combination of two directions for use of algae: algae biomass obtain... more The aim of this work was the combination of two directions for use of algae: algae biomass obtaining fodder minor and wastewater purification. Subject research have served cianofite species of algae: Nostoc gelatinosum, N. flagelliforme and Anabaena propinqua. As nutrient medium were used wastewater from livestock complexes (poultry and pigs) with a rich content of organic substances. Investigations carried out indicate that the largest quantity of biomass of Nostoc flageliforme is achieved in the cultivation with wastewater by 1% from pig complexes-13.2 g / l, Nostoc gelatinosum-1%-68 g / l. and Anabaena propinqua-5%-8.8g/l.

Synlett, 2009

... Chem. 1996, 35: 1168. 2a Tiyapiboonchaiya C, Pringle JM, Sun J, Byrne N, Howlett PC, MacFarla... more ... Chem. 1996, 35: 1168. 2a Tiyapiboonchaiya C, Pringle JM, Sun J, Byrne N, Howlett PC, MacFarlane DR, Forsyth M,Nat. Mater. 2004, 3: 29. ... Chem. Int. Ed. 2006, 45: 5867. 4d Dorjnamjin D, Ariunaa M, Shim YK,Int. J. Mol. Sci. 2008, 9: 807. 5a Xue H, Shreeve JM,Eur. J. Inorg. ...