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Abstrak :
To fulfill the requirement for synthetic fuel (synfuel) production in Fischer Tropsch process, in which syngas feed to the process has H2/CO mole ratio approaching 2, a lignite coal gasification is needed to satisfy this requirement. In this research, char particles were prepared by pyrolysis of lignite coal at controlled heating rates to obtain the highest possible surface area for gasification. The gasification used char with surface area of 172.5 m2/g, and catalyst K2CO3 in a fixed bed reactor. Steam/char mass ratio used in this research was varied 2.0; 3.0; 4.0 and the gasification temperature was varied 675, 750, 825oC. The result of this research showed that the highest H2/CO mole ratio of 2.07 corresponding to the mole ratio of gas yield/carbon of 1.13 was achieved at gasification temperature of 675oC using catalyst K2CO3 and at steam/char mass ratio of 2.0. However, at the same gasification conditions, but using no catalyst, H2/CO mole ratio and corresponding mole ratio of gas yield/carbon achieved were 3.02 and 0.42 respectively. This research found that the addition of catalyst K2CO3 in lignite coal char gasification adversely reduces mole ratio H2/CO ratio compared to that without catalysis. It is suspected that the high composition of mineral ash in ash reacts with K2CO3 catalyst which renders Boudouard reaction to considerably compete with water-gas reaction. The increases of gasification temperature and steam/carbon ratio both lower the mole ratio of H2/CO in syngas.

Abstrak :
Minyak atsiri kayu manis dapat diperoleh dari kulit batang kayu manis melalui teknik destilasi uap dan menghasilkan 0,06% rendemen. Proses selanjutnya minyak kayu manis dipisahkan melalui kromatografi kolom dan salah satu hasilnya yaitu fraksi A yang merupakan gabungan dari botol vial 1,2 dan 3 karena memiliki kemiripan spot pada KLT. Senyawa utama dari minyak kayu manis yakni sinamaldehid mengalami peningkatan luas area menjadi 20,95%. Reaksi prenilasi dari fraksi A yang menggunakan reagen prenil-bromida dan katalis heterogen K2CO3 diduga masuk pada senyawa trans-sinamaldehid, kalamenen, dan kumarin yang ditunjukkan pada perubahan spektrum IR, UV-Vis dan MS/MS. Hasil uji anti oksidan dari prenilasi fraksi A mengalami peningkatan kemampuan sebesar 51,61 % dibandingkan fraksi A itu sendiri. ...... The essential cinnamon oil can be obtained with steam distillation technique from the cinnamon bark and the yield percentage is 0,06 %. Furthermore the cinnamon oil was being extracted to chromatography column and the result is fraction A which is the combination of vial 1,2, and 3 who has the similarity spot on TLC. The main compound of cinnamon oil which is cinnamaldehyde had increase in widen area to 20,95 %. The prenylation of reaction of fraction A were using prenyl bromide reagent and heterogen K2CO3 catalyst suspected infiltrate the trans-cinnamaldehyde, calamenene, and coumarine that showed by the change of IR, UV-Vis and MS/MS spectrum. The result of antioxidant test from fraction A prenylation had increase the ability of antioxidant as much as 51,61 % than fraction A it self.

Abstrak :
Isatin (1H-indole-2,3-dione) merupakan senyawa heterosiklik yang memiliki bioaktivitas beragam. Senyawa spiro merupakan senyawa bisiklik yang terikat dengan satu atom yang sama dan memiliki bioaktivitas sebagai antioksidan. Pada penelitian ini, dilakukan sintesis senyawa turunan spiro[indol-azetidinon] berbasis isatin dan 5-kloroisatin yang diharapkan memiliki aktivitas antioksidan. Senyawa turunan spiro[indol-azetidinon] disintesis dari isatin dan 5-kloroisatin dengan variasi amina aromatik primer membentuk senyawa intermediet basa Schiff yang direaksikan dengan asam kloroasetat dan trietilamina dengan kehadiran katalis nanopartikel K2CO3. Nanopartikel K2CO3 disintesis dari K2CO3 anhidrat dengan etanol dan asam laurat yang dikarakterisasi menggunakan XRD, BET, dan SEM. Didapatkan nanopartikel K2CO3 memiliki ukuran kristal rata-rata sebesar 31,49 nm. Senyawa turunan spiro[indol-azetidinon] diidentifikasi menggunakan KLT serta dikarakterisasi menggunakan FTIR, UV-Vis, dan LC-MS. Didapatkan senyawa basa Schiff 1, 2, 3, dan 4 dengan persen yield masing-masing sebesar 18,21%, 10,06%, 21,13%, dan 7,39%. Didapatkan persen yield dari senyawa turunan spiro[indol-azetidinon] 1, 2, 3, dan 4 masing-masing sebesar 20,46%, 16,77%, 62,87%, dan 45,56%. Hasil uji aktivitas antioksidan dengan metode DPPH menunjukkan nilai IC50 untuk senyawa turunan spiro[indol-azetidinon] 1, 2, 3, dan 4 masing-masing sebesar 503,34 ppm, 586,52 ppm, 763,15 ppm, dan 933,22 ppm. ......Isatin (1H-indole-2,3-dione) is heterocyclic compound which has various bioactivities. Spiro compounds are bicyclic compounds that bound to the same atom and have bioactivity as antioxidants. In this research, synthesis of spiro[indole-azetidinone] derivatives based on isatin and 5-chloroisatin was carried out that expected to have antioxidant activity. Spiro[indole-azetidinone] derivatives were synthesized from isatin and 5-chloroisatin with a variety of primary aromatic amines formed Schiff base intermediate compounds that reacted with chloroacetic acid and triethylamine in the presence of K2CO3 nanoparticles catalyst. K2CO3 nanoparticles were synthesized from anhydrous K2CO3 with ethanol and lauric acid that characterized using XRD, BET, and SEM. It was found that K2CO3 nanoparticles had an average crystal size of 31.49 nm. Spiro[indole-azetidinone] derivatives were identified using TLC and characterized using FTIR, UV-Vis, and LC-MS. The Schiff base compounds 1, 2, 3, and 4 were obtained with yield percents of 18.21%, 10.06%, 21.13%, and 7.39%, respectively. The percent yield of spiro[indole-azetidinone] 1, 2, 3, and 4 derivatives were 20.46%, 16.77%, 62.87%, and 45.56%, respectively. The results of antioxidant activity tests using DPPH method showed the IC50 values ​​for spiro[indole-azetidinone] 1, 2, 3, and 4 derivatives were 503.34 ppm, 586.52 ppm, 763.15 ppm, and 933.22 ppm, respectively.

Abstrak :
Melinjo (Gnetum gnemon L.) mengandung banyak senyawa derivative stilbene yang memiliki banyak khasiat terutama dari sifat biologis dan farmakologisnya. Kulit melinjo diekstrak dengan etanol 80% selama 3 hari (diaduk sesekali). Senyawa derivative stilbene dipisahkan dari ekstrak kasar dengan kromatografi kolom dengan eluen n-heksana:etil asetat (sistim gradien). Hasil fraksinasi kromatografi kolom menghasilkan 3 isolat dengan dugaan terdapat lima senyawa derivative stilbene dan analognya (isorhapontigenin, resveratrol, gnetin D, gnetifolin K, gnetol) dan satu senyawa lignan ((+)-lirioresinol B) berdasarkan hasil karakterisasi LC-ESI-MS, FTIR, dan UV-Vis. Isolat 3 yang mengandung gnetol dan (+)-lirioresinol B dilakukan reaksi prenilasi dengan prenil bromida sebagai sumber gugus prenil dan katalis K2CO3 yang direfluks pada suhu 60°C selama 24 jam. Hasil karakterisasi LC-ESI-MS menunjukkan gnetol dan (+)- lirioresinol B berhasil diprenilasi dengan tambahan 1 gugus prenil. Spektrum FTIR menunjukkan gugus prenil terikat pada atom O dari gugus -OH serta spektrum UV-Vis menunjukkan pergeseran bathochromic dan hypsochromic pada produk prenilasi. Isolat sebelum dan sesudah reaksi prenilasi diuji aktivitas antioksidan dengan DPPH. Terjadi kenaikan nilai IC50 dari isolat terprenilasi sebesar 11,10%. ...... Melinjo (Gnetum gnemon L.) contain many compounds stilbene derivative which has many benefits especially from the biological and pharmacological properties. Bark of melinjo extracted with 80% ethanol for 3 days (stirring occasionally). Stilbene derivative compounds separated from crude extract by column chromatography with eluent n-hexane:ethyl acetate (gradient system). The results of the fractionation column chromatography resulted in 3 isolates with allegations contained five stilbene derivatives compounds (isorhapontigenin, resveratrol, gnetin D, gnetifolin K, gnetol) and one lignan compound ((+)-lirioresinol B) based on the results of the characterization of LC-ESI-MS, FTIR, and UV-Vis. Isolate 3 that containing gnetol and (+)-lirioresinol B conducted prenylation reaction with prenyl bromide as a source of prenyl group and K2CO3 as a catalyst with reflux system at a temperature of 60oC for 24 hours. The results of the characterization of LC-ESI-MS showed gnetol and (+)-lirioresinol B succeeded prenylated with an additional one prenyl group. The FTIR spectrum shows the prenyl group bound to the O atom of the -OH group and the UV - Vis spectra showed bathochromic and hypsochromic shift in prenylation product. Isolate 3 before and after the prenylation reaction tested antioxidant activity with DPPH. Percentage of IC50 of prenylated isolat is increasing to become 11,10%.

Abstrak :
Memiliki waktu tinggal yang singkat yang disebabkan oleh pengaruh pengosongan lambung menjadi keterbatasan amoksisilin dalam menangani bakteri Helicobacter pylori sebagai penyebab utama penyakit radang pada lapisan lambung. Sediaan pembawa obat sistem mengapung telah disintesis untuk menangani keterbatasan tersebut menggunakan matriks hidrogel semi-IPN kitosan-metil selulosa mengandung agen pembentuk pori APP KHCO3 dan K2CO3 dengan komposisi kitosan:metil selulosa 60:40 b/b , agen pengikat silang glutaraldehid 0,1 M 2 b/b terhadap kitosan , amoksisilin trihidrat digunakan sebagai model obat, konsentrasi agen pembentuk pori KHCO3 dan K2CO3 yang digunakan divariasikan, yaitu 1; 5; 10; 15; 20 terhadap massa total reagen. Pengaruh jenis variasi konsentrasi APP yang berbeda KHCO3 dan K2CO3 pada hidrogel telah diselidiki dan dibandingkan menggunakan parameter uji kemampuan mengapung dan persen porisitas. Pengaruh proses loading obat yang berbeda in situ post loading juga telah diselidiki dan dibandingkan menggunakan parameter persen efisiensi penjeratan dan persen disolusi. Karakterisasi terhadap sifat hidrogel dilakukan menggunakan Fourier Transform Infrared Spectroscopy FTIR, spektrofotometri UV-Vis, dan mikroskop stereo optik. Secara keseluruhan APP KHCO3 memiliki waktu awal mengapung lebih cepat dibanding K2CO3 dan memiliki kemampuan mengapung >3jam, kecuali pada komposisi 1 untuk kedua jenis APP. Berdasarkan evaluasi kemampuan mengapung, matriks hidrogel semi-IPN yang optimum terdapat pada penambahan komposisi agen pembentuk pori KHCO3 20. Hasil perbandingan sediaan optimum pada penelitian ini dengan sediaan optimum pada peneliti sebelumnya yang menggunakan APP CaCO3 15 dengan proses loading obat yang sama in situ loading , yaitu sediaan optimum yang menggunakan KHCO3 20 memiliki efisiensi penjeratan obat lebih tinggi dan persen disolusi yang lebih terkontrol dibanding sediaan menggunakan CaCO3 15 , 79 72 untuk efisiensi penjeratan KHCO3 dan CaCO3 berturut-turut. Proses loading obat in situ loading memberikan hasil efisiensi penjeratan lebih tinggi serta memiliki persen disolusi yang lebih terkontrol dibanding proses post loading pada sediaan dengan APP yang sama.

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Amoxicilin have shorter of a recidence time which are caused by influence gastric emptying. Floating drug delivery system as a resolve restriction of amoxcicilin in combating bacterial Helicobacter pylory had been synthesized by based on semi IPN hydrogel chitosan methyl cellulose containing pore forming agent PFA KHCO3 and K2CO3 with the composition of chitosan methyl cellulose 60 40 w w , glutaraldehyde as a crosslingking agent 0.1 M 2 w w to chitosan , amoxcicilin trihydrate as a drug model, and pore forming agent KHCO3 and K2CO3 with varied concentrations were 1 5 10 15 20 to the total mass of reagents. The effect of kind and varied concentrations of PFA on hydrogel characterizations had been investigated and compared by using floating ability and percent porosity parameters. The effect of kind drug loading process in situ and post loading also had been investigated and compared by using encapsulation efficiency and percent drug dissolution parameters. Characterizations of the hydrogel were carried out by using Fourier Transform Infrared Spectroscopy FTIR , UV Vis spectrophotometry, and stereo optical microscope. Overall, KHCO3 incorporated hydrogels showed faster floating lag time than K2CO3 and both had a floating time more than 3 hours, except on 1 composition of both PFA. Based on floating ability evaluation, optimum composition of PFA incorporated hydrogel was KHCO3 20 . The results of compared between optimum composition for this research and optimum composition for previous research used PFA CaCO3 15 with the same drug loading prosess in situ showed that KHCO3 incorporates hydrogel had the higher encapsulation efficiency and more controlled drug release profile than CaCO3 incorporated hydrogel, 79 72 for encapsulation efficiency KHCO3 20 and CaCO3 15 , respectively. The results of compared loading drug process with the same PFA, in situ loading drug process showed higher encapsulation efficiency and drug release profile more controlled than post loading drug process.