Ahmad Randy
Polymer Chemistry Group, Research Center for Chemistry Indonesian Institute of Sciences (LIPI) Kawasan Puspiptek Serpong, Tangerang 15314 – Indonesia

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Determination of The Active Asiaticoside Content in Centella asiatica as Anti-Cellulite Agent Sondari, Dewi; Harmami, Sri Budi; Ghozali, M; Randy, Ahmad; S, Athanasia Amanda; Irawan, Yan
Indonesian Journal of Cancer Chemoprevention Vol 2, No 2 (2011)
Publisher : Indonesian Research Gateway

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Abstract

Centella  asiatica  accumulates  large  quantities  of  pentacyclic  triterpenoid saponins,  collectively  known  as  centelloids.  These  terpenoids  include  asiaticoside, centelloside,  madecassoside,  brahmoside,  brahminoside,  thankuniside,  sceffoleoside, centellose, asiatic-, brahmic-, centellic- and madecassic acids. Preparations of C. asiatica are  used  in  traditional  and  alternative  medicine  due  to  the  wide  spectrum  of pharmacological  activities  associated  with  these  secondary  metabolites,  such  as anticellulite agent. Asiaticoside was found in Centella asiatica. In this present study, the asiaticoside was extracted using methanolic and ethanolic solvent. Determination of the asiaticoside  content  in  the  extract  was  conducted  with  High Performance  Liquid Chromatography (HPLC), Thin Layer Chromatography (TLC), and Fourier Transform Infra Red (FTIR). Samples of C.  asiatica used in this study came from three different plantation  areas,  Bogor,  Lembang  and  Solo.  Asiaticoside  content  in  the  methanolic extract  from  Bogor,  Lembang,  and  Solo  samples  were  2.82%;  2.68%;  and  2.8% respectively. Asiaticoside in ethanolic extract from Bogor, Lembang, and Solo samples were 2.79%; 2.75%; and 2.91% respectively. Two way ANOVA study showed that there was  significant  difference  between  types  of  solvent  used  in  extraction  and  the asiaticoside  content  in  the  obtained  extract,  significant  difference  between  varied plantation area and obtained asiaticoside content, and significant difference between interactions of different solvent with different plantation area.     Key words: Centella asiatica, asiaticoside, anticellulite, medicine, metabolites  
MODIFIKASI KARET ALAM MENJADI BAHAN ELASTOMER TERMOPLASTIK Suhardjo, Kuntari Adi; Basuki, Ariyadi; ., Surasno; Randy, Ahmad; Sondari, Dewi
Jurnal Riset Industri Vol 5, No 3 (2011): Peningkatan Nilai Tambah dan Produktivitas Industri
Publisher : Badan Penelitian dan Pengembangan Industri

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Abstract

Karet alam  bersifat elastomer dan termoseting, sehingga sulit  untuk dibentuk dan tidak dapat didaur ulang., Modifikasi karet alam menjadi bahan elastomer termoplastik dimaksudkan untuk memperoleh bahan yang mudah dicetak  menjadi  produk  jadi   dan  dapat  dapat  didaur  ulang  sehingga  tidak  merusak  lingkungan.   Untuk mendapatkan teknologi pembuatan elastomer termoplastik dari karet alam  telah dilakukan percobaan  dengan metoda pencangkokan (grafting)   secara polimerisasi emulsi antara karet alam lateks dengan monomer stirena dan metil metakrilat. Polimerisasi emulsi dilakukan pada suhu 65°C selama 6 jam. Perbandingan komposisi karet alam lateks dan monomer di variasi:  80:20; 70:30; 60:40; 50:50 (% berat) dengan komposisi monomer stirena dan metil metakrilat   1:1, menggunakan dua jenis inisiator yaitu potassium persulfat 2 % berat atau ammonium peroksodisulfat divariasi 2, 2,5, 5 % berat serta emulsifier sodium dodesil sulfat divariasi: 0, 1, 1,5,  2, 5 % berat. Dari hasil analisa 1 H NMR dan FTIR terlihat bahwa proses cangkok monomer stirena dan metil metakrilat telah terjadi pada tulang punggung karet alam. Puncak pada frekuensi 833 cm -1 menunjukkan pita RzC=CHR, frekuensi 1743 dan 1519 cm-1menunjukkan pita C=O (gugus karbonil dari metil metakrilat) dan pita C=C (cincin benzena dari stirena). Efisiensi cangkok maksimum sebesar 97,60% diperoleh  pada komposisi 70% karet alam lateks dan 30% monomer dimana komposisi monomer antara stirena dan metil metakrilat adalah 1: 1 menggunakan inisiator potasium persulfat 2% dan emulsifier sodium dodesil sulfat 1%.Kata  kunci: Elastomer termoplastik, kopolimer cangkok, karet alam lateks, stirena, metilmetakrilat.
MODIFIKASI KARET ALAM MENJADI BAHAN ELASTOMER TERMOPLASTIK Suhardjo, Kuntari Adi; Basuki, Ariyadi; ., Surasno; Randy, Ahmad; Sondari, Dewi
Jurnal Riset Industri Vol 5, No 3 (2011): Peningkatan Nilai Tambah dan Produktivitas Industri
Publisher : Badan Penelitian dan Pengembangan Industri

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (6742.063 KB)

Abstract

Karet alam  bersifat elastomer dan termoseting, sehingga sulit  untuk dibentuk dan tidak dapat didaur ulang., Modifikasi karet alam menjadi bahan elastomer termoplastik dimaksudkan untuk memperoleh bahan yang mudah dicetak  menjadi  produk  jadi   dan  dapat  dapat  didaur  ulang  sehingga  tidak  merusak  lingkungan.   Untuk mendapatkan teknologi pembuatan elastomer termoplastik dari karet alam  telah dilakukan percobaan  dengan metoda pencangkokan (grafting)   secara polimerisasi emulsi antara karet alam lateks dengan monomer stirena dan metil metakrilat. Polimerisasi emulsi dilakukan pada suhu 65°C selama 6 jam. Perbandingan komposisi karet alam lateks dan monomer di variasi:  80:20; 70:30; 60:40; 50:50 (% berat) dengan komposisi monomer stirena dan metil metakrilat   1:1, menggunakan dua jenis inisiator yaitu potassium persulfat 2 % berat atau ammonium peroksodisulfat divariasi 2, 2,5, 5 % berat serta emulsifier sodium dodesil sulfat divariasi: 0, 1, 1,5,  2, 5 % berat. Dari hasil analisa 1 H NMR dan FTIR terlihat bahwa proses cangkok monomer stirena dan metil metakrilat telah terjadi pada tulang punggung karet alam. Puncak pada frekuensi 833 cm -1 menunjukkan pita RzC=CHR, frekuensi 1743 dan 1519 cm-1menunjukkan pita C=O (gugus karbonil dari metil metakrilat) dan pita C=C (cincin benzena dari stirena). Efisiensi cangkok maksimum sebesar 97,60% diperoleh  pada komposisi 70% karet alam lateks dan 30% monomer dimana komposisi monomer antara stirena dan metil metakrilat adalah 1: 1 menggunakan inisiator potasium persulfat 2% dan emulsifier sodium dodesil sulfat 1%.Kata  kunci: Elastomer termoplastik, kopolimer cangkok, karet alam lateks, stirena, metilmetakrilat.
Control of Biodegradability of Polyurethane Foam Based on Palm Oil by Ratio of Soft Segment on the Polymer Backbone Haryono, Agus; Triwulandari, Evi; Sondari, Dewi; Randy, Ahmad; Ridwanuloh, Asep Muhamad
ANNALES BOGORIENSES Vol 14, No 1 (2010): Annales Bogorienses
Publisher : Research Center for Biotechnology - Indonesian Institute of Sciences (LIPI)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.1234/35

Abstract

Polyurethane  is  polymer  synthetic  which  is  formed  by  reaction  between  polyols  and  polyisocyanates.polyols  are  compounds  which  contain  two or  more  hydroxyl  groups.  Polyurethane  can  be  applied  in  various forms,  such  as  foam,  elastomeric,  coating  and  adhesive.  In  this  work,  we  developed  pol yurethane  foams  by using polyols  based  on  palm  oil.  Palm  oil  based  polyols  as  soft  segments  in  the  polyurethane  backbone accelerate biodegradable process of the polyurethane. Biodegradability is the ability of material to be utilized as a carbon source by  microorganisms and converted safely into carbon dioxide, biomass and water. Commercially available  polyurethane  foams  are  usually  produced  from  petrochemical  based  polyols  that  they  are  not biodegradable. The biodegradability study was conducted by using  Aspergillus niger  (fungi) and  Pseudomonas aeruginosa(bacteria),  with  variation  of  method  and  media  for  biodegradation.  Rigid  polyurethane  foam  was synthesized by  using  one  shoot  process  method,  which  is  reaction  between  palm based polyol  mixture  and methylene diphenly diisocyanate (MDI) at room temperature. The effect of variation of ratio of polyisocyanates (NCO) as hard segment and polyols (OH) as soft segment to the properties of polyurethane foams were studied in detail. Study of the effect NCO/OH ratio   was conducted with variation ratio of 0.8,  1.0  and  1.2. Increasing hard segment (NCO) ratio to the soft segment (OH) affected in the decreasing of hydrophilicity of foam. Thus,the penetration of water into bulk of polymer decreased. The biodegradability  of foam was also affected by the soft segment ratio on the polymer backbone.   Keywords: biodegradable, polyurethane, palm oil, polyols, soft segment
Cytotoxic of Usnic Acid Isolated from Ramalina sp.: Cytotoxic of Usnic Acid Isolated from Ramalina sp. Darmawan, Akhmad; Maulidiyah; Megawati; Ariani, Novita; Aisya, Sitti; Sukirno; Randy, Ahmad; Primahana, Gian; Hendra, Medi; Nurdin, Muhammad
Journal of Tropical Life Science Vol. 14 No. 2 (2024)
Publisher : Journal of Tropical Life Science

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.11594/jtls.14.02.14

Abstract

Ramalina sp. (Ramalinaceae) is a type of lichen known to contain many active secondary metabolite compounds that have the potential to be used as medicine or medicinal raw materials. One of the biological activities possessed by Ramalina sp. lichen is its anticancer activity. This research aims to isolate and identify active secondary metabolite compounds from the methanol extract of the Ramalina sp. lichen and to find out the cytotoxic activity of the isolated compound against MCF7 breast cancer cells. Compound 1 (usnic acid) was successfully isolated from fraction A. The isolation and purification process was carried out starting with a maceration process using acetone solvent, followed by silica gel column chromatography using a gradient solvent system consisting of n-hexane, n-hexane:EtOAc, EtOAc, EtOAc:MeOH, and MeOH with 5% increment of polarity to obtain 17 fractions (F-1 to F-17). From the 17 fractions obtained, fraction 3 (F-3) and fraction 4 (F-4) (eluted with n-hexane:EtOAc 30%), which had the same TLC profile, were combined and named as fraction A. Compound 1 (50 mg) is a yellow needle crystal that was formed in a bottle of fraction A, which was obtained after the process of combining fractions F-3 and F-4 and solvent evaporation process. The crystals were then separated and purified with CHCl3 and MeOH. Compound 1 was then characterized based on spectroscopic data. Various spectroscopic analysis data, including FTIR, 1D- and 2D-NMR, and LC-ESI-MS, show that Compound 1 is a dibenzofuran derivative compound with 18 carbons (3 from carbonyl groups (C=O) and 3 from methyl groups) and 2 hydroxyl (-OH). Cytotoxicity assay showed that at a low concentration of 18.75 ug/mL, Compound 1 caused a 67.06% decrease in MCF7 viability
Cytotoxic of Usnic Acid Isolated from Ramalina sp.: Cytotoxic of Usnic Acid Isolated from Ramalina sp. Darmawan, Akhmad; Maulidiyah; Megawati; Ariani, Novita; Aisya, Sitti; Sukirno; Randy, Ahmad; Primahana, Gian; Hendra, Medi; Nurdin, Muhammad
Journal of Tropical Life Science Vol. 14 No. 2 (2024)
Publisher : Journal of Tropical Life Science

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.11594/jtls.14.02.14

Abstract

Ramalina sp. (Ramalinaceae) is a type of lichen known to contain many active secondary metabolite compounds that have the potential to be used as medicine or medicinal raw materials. One of the biological activities possessed by Ramalina sp. lichen is its anticancer activity. This research aims to isolate and identify active secondary metabolite compounds from the methanol extract of the Ramalina sp. lichen and to find out the cytotoxic activity of the isolated compound against MCF7 breast cancer cells. Compound 1 (usnic acid) was successfully isolated from fraction A. The isolation and purification process was carried out starting with a maceration process using acetone solvent, followed by silica gel column chromatography using a gradient solvent system consisting of n-hexane, n-hexane:EtOAc, EtOAc, EtOAc:MeOH, and MeOH with 5% increment of polarity to obtain 17 fractions (F-1 to F-17). From the 17 fractions obtained, fraction 3 (F-3) and fraction 4 (F-4) (eluted with n-hexane:EtOAc 30%), which had the same TLC profile, were combined and named as fraction A. Compound 1 (50 mg) is a yellow needle crystal that was formed in a bottle of fraction A, which was obtained after the process of combining fractions F-3 and F-4 and solvent evaporation process. The crystals were then separated and purified with CHCl3 and MeOH. Compound 1 was then characterized based on spectroscopic data. Various spectroscopic analysis data, including FTIR, 1D- and 2D-NMR, and LC-ESI-MS, show that Compound 1 is a dibenzofuran derivative compound with 18 carbons (3 from carbonyl groups (C=O) and 3 from methyl groups) and 2 hydroxyl (-OH). Cytotoxicity assay showed that at a low concentration of 18.75 ug/mL, Compound 1 caused a 67.06% decrease in MCF7 viability