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"Inhibitor ramah lingkungan saat ini diperlukan untuk mengurangi dampak pencemaran dari inhibitor anorganik. Penelitian ini mempelajari pengaruh injeksi ekstrak daun sirsak dengan pelarut tiga tingkat sebagai inhibitor organik terhadap baja karbon rendah API 5L grade A dalam larutan air terproduksi. Berdasarkan pengujian weight loss dari seluruh sampel uji, sampel 8 hari dengan penambahan inhibitor 2 ml menunjukan nilai efisiensi paling tinggi yakni sebesar 52.62 %. Hasil uji polarisasi dan EIS dengan pelarut tiga tingkat didapatkan pelarut etanol mempunyai nilai efisiensi paling besar: 88.52%, sedangkan pelarut semi polar dan non polar nilai efisiensi nya hampir sama. Data dari EIS menunjukkan tahanan larutan menjadi turun dengan semakin meningkat nya penambahan inhibitor ekstrak daun sirsak. Uji FTIR memperlihatkan bahwa terdapat gugus fungsi dari ekstrak daun sirsak dan senyawa aktif nya adalah tipe polifenol.

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Green inhibitors are now increasingly needed to reduce the adverse environmental impacts of the inorganic inhibitor. This research studied the effects of injection of soursop leaves extract in three-level solvents (polar, semi polar and non polar) as an organic inhibitor for the low-carbon steel API 5L of grade A in produced water solution. Based on weight loss test of the entire sample, the 8 days's sample with addition of 2 ml inhibitor from soupsop leaves extract showed the highest efficiency value which amounted to 52.62%. The polarization and EIS tests for three levels's solvents show that the ethanol solvent (type of polar) has the greatest efficiency values: 88.52%, while the efficiency value of non-polar and semi-polar solvent is almost without difference. EIS data showed that inhibiting power of the solution decreases when the inhibitor of soursop leaves extract is increasingly added. FTIR test showed that there is a functional group in the soursop leaves's extract and the active compound is a kind of polyphenol."

"Tesis ini mempelajari mengenai pengaruh injeksi ekstrak Andaliman dan Alpha-Tocopherol sebagai green corrosion inhibitor pada baja API 5L dalam larutan HCl 1M. Dengan pengujian weight loss diperlihatkan bahwa inhibitor campuran antara ekstrak Andaliman dan Alpha-Tocopherol mampu menurunkan laju korosi dengan efisiensi 92.07 pada konsentrasi inhibitor 2 ml Andaliman 0.5 ml Alpha-Tocopherol. Dari pengujian polarisasi ditunjukkan bahwa inhibitor campuran antara ekstrak Andaliman dan Alpha-Tocopherol menggeser kurva polarisasi kearah atodik dan katodik mixed type inhibitor , yang menunjukkan ciri utama sebagai inhibitor dari bahan organik. Pengujian dengan FTIR dan GCMS memperkuat dugaan bahwa inhibitor ekstrak Andaliman dan Alpha-Tocopherol sebagai inhibitor adsorpsi/film forming.

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This thesis is intended to study the influences of Andaliman extract and Alpha- Tocopherol injection as green corrosion inhibitor for API 5L steel in HCl 1M solution. By weight loss analysis, it show that mixed inhibitor from andaliman extract and Alpha-Tocopherol can reduce corrosion rate with efficiency up to 92.07 % under inhibitor injection about 2 ml Andaliman + 0.5 ml Alpha- Tocopherol. By polarization, it is shown that inhibitor shift polarisation curves for both of anodic and cathodic polarisation (mixed type inhibitor), shows that inhibitor have characteristic as inhibitor from organic material. By FTIR and GCMS analysis can be concluded that inhibitor from Andaliman and A- Tocopherol act inhibition by adsorption/film forming corrosion inhibitor."

"Ekstrak areca flower telah diteliti sebagai inhibitor korosi pada baja API 5L Gr. B pada lingkungan 1 M HCl dengan menggunakan pengujian Linear Polarisasi dan Electrochemical Impedance Spectroscopy EIS. Penambahan konsentrasi inhibitor 4 ml, 8 ml, 12 ml, 16 ml, dan 20 ml dapat meningkatkan efisiensi inhibitor. Efisiensi inhibitor optimum terjadi pada saat penambahan konsentrasi inhibitor 20 ml sebesar 96.6 pada pengujian Electrochemical Impedance Spectroscopy EIS. Senyawa polifenol dan flavonoid yang terkandung dalam areca flower dapat menginhibisi korosi secara adsorpsi fisika yang membentuk lapisan monolayer yang dapat menghambat terjadinya korosi. Adsorpsi terjadi secara spontan sesuai dengan adsorpsi isotermal Langmuir. Sesuai hasil pengujian polarisasi menunjukkan ekstrak areca flower memiliki tipe inhibisi campuran mixed-type . Nilai energi bebas adsorpsi -7.026 kJ/mol menunjukkan bahwa adsorpsi molekul inhibitor adalah adsorpsi fisika.

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Areca flower has been investigated as green corrosion inhibitor on API 5L Gr B in solution 1 M HCl acidic using Linear polarization and Electrochemical Impedance Spectroscopy EIS . Addition of 4 ml, 8 ml, 12 ml, 16 ml, and 20 ml inhibitor corrosion increase efficiency of the inhibitor. Optimum inhibition efficiency occurs at addition at concentration 20 ml is 96.6 on Electrochemical Impedance Spectroscopy EIS testing. Polyphenolic and flavanoid compounds contained in the areca flower inhibit corrosion by physical adsorption, to form a monolayer which can inhibit corrosion. Adsorption occurs spontaneously in accordance with Langmuir isothermal adsorption. The polarization showed that the areca flower extract acts through mixed ndash type inhibition. The value of the free energy 7.026 kJ mol of adsorption indicated that the adsorption of inhibitor molecules was typical of physical adsorption."

"Pada proses pre-commisioning jaringan pipa bawah laut diperlukan pencegahan korosi dimana laju korosi material baja API 5L grade B di dalam larutan 3,5 % NaCl teraerasi pada kondisi steady masih relatif tinggi yang dapat mencapai lebih dari 20 mpy (0,5 mm/tahun). Upaya pencegahan korosi pada saat proses hydrotest dengan media air laut dilakukan dengan penambahan inhibitor anorganik yang mengandung zat corrosion inhibitor, oxygen scavenger dan biocide sehingga diperlukan bahan organik alternatif ramah lingkungan dengan kinerja yang lebih baik. Tujuan utama dari penelitian ini adalah untuk menginvestigasi efisiensi dari penggunaan campuran ekstrak sarang semut dan sirih merah sebagai alternatif inhibitor ramah lingkungan atau bahan campuran untuk mengurangi penggunaan inhibitor anorganik pada perlindungan korosi material baja API 5L Grade B dalam lingkungan 3,5% NaCl.Kemampuan inhibisi korosi dari hasil ekstrak bahan alami diinvestigasi dengan menggunakan pengujian Tafel polarisasi dan Electrochemical Impedance Spectroscopy (EIS) serta diverifikasi dengan pengujian kehilangan berat. Kandungan senyawa aktif dalam ekstrak sarang semut dan sirih merah beserta senyawa teradsorpsi pada permukaan logam dan mekaniseme inhibisi elektrokimia diinvestigasi dengan pengujian EIS, FTIR dan model adsorpsi isoterm. Pada konsentrasi campuran green inhibitor 2ml sarang semut + 1ml sirih merah, effisiensi inhibitor dapat mencapai 73,66%. Pada penggunaan sebagai inhibitor campuran dengan inhibitor kimia pada konsentrasi campuran 1ml kimia + 2ml green inhibitor, dapat menurunkan laju korosi secara signifikan dari 0,42 mm/year menjadi 0,03 mm/year dengan efisiensi mencapai 93,15%. Inhibitor korosi tersebut berpengaruh terhadap kurva polarisasi anodik maupun katodik sehingga dapat berperan sebagai mixed inhibitor.Pengujian FTIR menunjukan adanya gugus-gugus fungsi ikatan kimia yang berkombinasi sebagai pembentuk lapisan (film forming) seperti Gugus hidroksil, karbonil, aromatik, alkane dan amina. Adsorpsi senyawa-senyawa terkandung dalam inhibitor sarang semut dan sirih merah pada permukaan logam terjadi spontan mengikuti Langmuir adsorpsi isoterm. Hasil ini sesuai dengan hipotesis awal bahwa ekstrak sarang semut dan sirih merah yang mengandung senyawa antioksidan dapat mencegah proses oksidasi pada permukaan logam sehingga akan mengurangi laju korosi.

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During pre-commissioning of subsea pipeline are require corrosion prevention since the corrosion rate of steel material of API 5L grade B in 3.5% NaCl aerated solution under steady state condition is still relatively high (can reach more than 0,5 mm/year). Method to prevent the corrosion during subsea pipeline hydrotest using seawater is generally by the addition of inorganic inhibitor containing corrosion inhibitor agent, oxygen scavenger and biocide, so that require to find out the alternative eco- friendly materials with better performance. The main objective of this study is to investigate the efficiency of the use of mixture of extract of myrmecodia pendans and piper crocatum as an alternative of eco-friendly inhibitor or a compound for reducing the use of inorganic inhibitors for corrosion protection of steel material API 5L Grade B in 3,5% NaCl Environmental.

The corrosion inhibition ability of natural ingredient extraction are investigated by using tafel polarization test and electrochemical impedance spectroscopy (EIS) and verified by weight loss test. The content of the active compounds in the extract of Myrmecodia Pendans and Piper Crocatum along with adsorption compound on metal surfaces and electrochemical inhibition mekaniseme are investigated by EIS, FTIR testing and model of the Langmuir adsorption isotherm. The addition of mixed green inhibitor concentration of 2ml myrmecodia pendans and 1ml piper crocatum is resulted in approximately 73.66% inhibitor efficiency while the addition of mixed green inhibitor into chemical inhibitor with concentration of 1ml for chemical and 2ml for green inhibitor are significantly reduce the corrosion rate from 0.42 mm/year to be 0.03 mm/year with approximately 93.15% inhibitor efficiency.

The green inhibitor affected the cathodic as well as the anodic polarization curves which were known as mixed corrosion inhibitor type. The type of chemical bonds on the steel surface layer was analyzed by FTIR method which indicated hydroxyl, carbonyl, aromatic, alkane and amine group. The adsorption of compounds contained in the myrmecodia pendans and piper crocatum inhibitor on a metal surface are occur spontaneously follows the Langmuir adsorption isotherm. These results are consistent with the initial hypothesis that the extract of myrmecodia pendans and piper crocatum contains antioxidant compound which can prevent the oxidation process in the metal surface thereby will reducing the corrosion rate."

"Penggunaan sumber Panas bumi melibatkan pendinginan pada fluida Panas bumi dengan cara mengekstrak panasnya. Pada kasus fluida Panas bumi suhu tinggi, pengendapan amorphous silika dari larutan membentuk kerak silika adalah masalah utama dalam efisiensi ekstraksi panas. Pengurangan atau bahkan penghilangan pembentukan kerak silika dengan penanganan yang tepat pada air dapat membuka kesempatan meningkatkan efisiensi dalam penggunaan sumber Panas bumi suhu tinggi.Tujuan penelitian ini adalah untuk mengetahui kemungkinan pembentukan kerak silika dari contoh air Panas bumi lapangan panas bumi Lahendong, Sulawesi Utara dan cara-cara pencegahannya dengan menggunakan pengaturan pH dan scale inhibitor. Untuk mengetahui kemungkinan terbentuknya pengkerakan silika maka dilkakukan sejumlah perlakuan dengan volume larutan 300 ml dengan memvariasikan pH sampel kontrol 3,4,5,6,7,8,9,10,11, dan 12. Kemudian sampel ditambahkan NaCl hingga konsentrasi NaCl menjadi berturut-turut 1000, 2000, 3000, 4000, 5000, 6000, 7000, 8000, 9000, 10000 ppm. Dilakukan juga inhibisi pengkerakan dengan menggunakan asam borat dan memvariasikan penambahan asam borat berdasarkan variasi berat, yaitu: 1, 5, 10, 20, 50 miligram. Semua perlakuan, baik variasi pH maupun penambahan NaCl dan uji inhibisi dengan asam borat, diakhiri dengan menjenuhkan larutan dengan pemanasan hingga volumenya kira-kira 100 ml.Dari percobaan yang dilakukan ternyata diketahui bahwa pengkerakan paling besar terjadi pada pH 7 dang kandugngan NaCl 10000 ppm. Sedangkan untuk uji inhibisi yang paling efektif pada penambahan berat asam borat sebanyak 50 mg dengan volume sampel 300 ml. Kata Kunci: Pengkerakan silika, Scaling, scale inhibitor."

"[ABSTRAKPenelitian pemanfaatan ekstrak tumbuh-tumbuhan sebagai inhibitor korosibelakangan ini semakin meningkat seiring dengan meningkatnya permintaanpenggunaan bahan-bahan kimia yang ramah lingkungan. Pemanfaatan ekstraktumbuh-tumbuhan sebagai inhibitor korosi menjadi penting mengingatkarakteristiknya ramah lingkungan (green inhibitor), mudah ketersediaannnya,sumberdaya yang melimpah dan dapat diperbaharui, prosedur produksi yangsederhana, dan biaya produksi yang cukup kompetitif. Dalam penelitian inidilakukan pengujian eksperimental efek sinergis jenis inhhibitor baru yaituekstrak ubi ungu (Ipomoea batatas L.) yang memiliki kandungan utamaantosianin dengan inhibitor komersial berbasis amine (aniline) dan denganinhibitor asam askorbat.Penelitian bertujuan untuk menganalisis laju kororsi dan efisiensi inhibisikorosi logam baja (API 5L) di dalam lingkungan air terproduksi menggunakaninhibitor campuran ekstrak ubi ungu dan inhibitor komersial berbasis amine(aniline). Selain itu dilakukan pula analisis laju korosi, efisiensi inhibisi,mekanisme proteksi dan model lapisan inhibisi korosi logam baja (API 5L) didalam lingkungan 3,5% NaCl menggunakan inhibitor campuran ekstrak ubi ungudan asam askorbat.Metode pengukuran laju korosi dan efisiensi inhibisi dilakukanmenggunakan elektrokimia kurva polarisasi. Mekanisme korosi diteliti denganmenggunakan metode Electrochemical Impedance Spectroscopy (EIS). Untukmenganalisis model lapisan inhibisi dilakukan dengan menggunakan metodeFourier Transform Infra Red (FTIR) spectroscopy.Hasil penelitian menunjukan bahwa pencampuran ekstrak ubi ungumemiliki kemampuan sinergis dengan inhibitor komersial berbasis amine (aniline)pada fraksi volume ekstrak ubi ungu sebesar 25% dengan menghasilkan efisiensiinhibisi sebesar 82,14%. Sebagai pembanding, pada sistem yang samapenggunaan esktrak ubi ungu saja menghasilkan efisiensi inhibisi 68,30%,sedangkan penggunaan inhibitor komersial berbasis amine (aniline) sajamenghasilkan efisiensi inhibisi 74,88%.Penambahan volume ekstrak ubi ungu dari 1 mL hingga 4 mL kedalaminhibitor asam askorbat 10-4 M meningkatkan efisiensi inhibisi korosi logam baja(API 5L) dalam larutan 3,5% NaCl dari efisiensi inhibisi sebesar 23,37% menjadi57,52%. Campuran inhibitor korosi tersebut berpengaruh terhadap kurvapolarisasi anodik maupun katodik sehingga dapat berperan sebagai mixedinhibitor. Pengujian EIS menunjukan proses korosi dikontrol oleh mekanismepasivasi yang ditunjukan oleh adanya peningkatan tahanan permukaan korosi.Pada lapisan permukaan terjadi proses adsorpsi dan pembentukan kelatorgano (flavonoid) logam dimana ekstrak ubi ungu dengan kandungan utamaantosianin berperan sebagai pembentuk metal-chelated. Pembentukan kelatekstrak ubi ungu-Fe-asam askorbat terjadi pada gugus hidroksil dan karbonil.Lokasi terjadinya ligan kelat ekstrak ubi ungu dengan kandungan utma antosianinterjadi pada ikatan 3?, 4? Dihydroxy cincin B atau 3-Hydroxy 4-Carbonyl cincin C;

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ABSTRACTResearch of utilization of plant extracts as a corrosion inhibitor recentlyincreased along with the increasing demand for the use of chemicals that areenvironmentally friendly. Utilization of plant extracts as a corrosion inhibitorbecomes important given the characteristics of environmentally friendly (greeninhibitor), easy availability, resources are abundant and renewable, the productionprocedure is simple, and the production costs are quite competitive. In thisresearch, experimental testing of the synergistic effects of new types inhibitor ieextract purple potato (Ipomoea batatas L.) which has the main content ofanthocyanin with commercial inhibitor-based amine (aniline) and with ascorbicacid inhibitors.The study aims to analyze the rate of corrosion and metal corrosioninhibition efficiency of steel (API 5L) in the produced water environment using amixed inhibitor purple sweet potato extract and commercial-based inhibitors ofamine (aniline). In addition, the corrosion rate analysis was also performed,inhibition efficiency, protection mechanisms and models of metal corrosioninhibition layer steel (API 5L) in the neighborhood of 3.5% NaCl using a mixedinhibitor purple sweet potato extract and ascorbic acid.Method of measuring the rate of corrosion and inhibition efficiency wasperformed using electrochemical polarization curves. Corrosion mechanismsinvestigated by Electrochemical Impedance Spectroscopy (EIS). To analyze themodel layer of inhibition were calculated using Fourier Transform Infra Red(FTIR) spectroscopy.The results showed that mixing purple sweetpotato extract has the abilityto synergistically with commercial inhibitor-based amine (aniline) in purplesweetpotato extract volume fraction of 25% with a yield of 82.14% inhibitionefficiency. For comparison, the same system using purple sweet potato extractonly produce inhibition efficiency of 68.30%, while the use of commercial-basedinhibitors of amine (aniline) alone resulted in inhibition efficiency of 74.88%.The addition of purple sweet potato extract volume of 1 mL to 4 mL intoascorbic acid inhibitors 10-4 M improving steel metal corrosion inhibitionefficiency (API 5L) in a solution of 3.5% NaCl of inhibition efficiency of 23.37%to 57.52%. The corrosion inhibitor mixture affect the anodic and cathodicpolarization curves so that it can act as a mixed inhibitor. Testing EIS shows thecorrosion process is controlled by the passivation mechanism indicated by anincrease in the surface resistance of corrosion.On the surface layer of a process of adsorption and formation of organochelates (flavonoids) in which the metal purple sweet potato extract with the maincontent of anthocyanins act as forming metal-chelated. Location of the chelatingligand purple sweet potato extract with the main content of anthocyanins occur inbond 3 ', 4' dihydroxy ring B or 3-Hydroxy 4-Carbonyl ring C.;Research of utilization of plant extracts as a corrosion inhibitor recentlyincreased along with the increasing demand for the use of chemicals that areenvironmentally friendly. Utilization of plant extracts as a corrosion inhibitorbecomes important given the characteristics of environmentally friendly (greeninhibitor), easy availability, resources are abundant and renewable, the productionprocedure is simple, and the production costs are quite competitive. In thisresearch, experimental testing of the synergistic effects of new types inhibitor ieextract purple potato (Ipomoea batatas L.) which has the main content ofanthocyanin with commercial inhibitor-based amine (aniline) and with ascorbicacid inhibitors.The study aims to analyze the rate of corrosion and metal corrosioninhibition efficiency of steel (API 5L) in the produced water environment using amixed inhibitor purple sweet potato extract and commercial-based inhibitors ofamine (aniline). In addition, the corrosion rate analysis was also performed,inhibition efficiency, protection mechanisms and models of metal corrosioninhibition layer steel (API 5L) in the neighborhood of 3.5% NaCl using a mixedinhibitor purple sweet potato extract and ascorbic acid.Method of measuring the rate of corrosion and inhibition efficiency wasperformed using electrochemical polarization curves. Corrosion mechanismsinvestigated by Electrochemical Impedance Spectroscopy (EIS). To analyze themodel layer of inhibition were calculated using Fourier Transform Infra Red(FTIR) spectroscopy.The results showed that mixing purple sweetpotato extract has the abilityto synergistically with commercial inhibitor-based amine (aniline) in purplesweetpotato extract volume fraction of 25% with a yield of 82.14% inhibitionefficiency. For comparison, the same system using purple sweet potato extractonly produce inhibition efficiency of 68.30%, while the use of commercial-basedinhibitors of amine (aniline) alone resulted in inhibition efficiency of 74.88%.The addition of purple sweet potato extract volume of 1 mL to 4 mL intoascorbic acid inhibitors 10-4 M improving steel metal corrosion inhibitionefficiency (API 5L) in a solution of 3.5% NaCl of inhibition efficiency of 23.37%to 57.52%. The corrosion inhibitor mixture affect the anodic and cathodicpolarization curves so that it can act as a mixed inhibitor. Testing EIS shows thecorrosion process is controlled by the passivation mechanism indicated by anincrease in the surface resistance of corrosion.On the surface layer of a process of adsorption and formation of organochelates (flavonoids) in which the metal purple sweet potato extract with the maincontent of anthocyanins act as forming metal-chelated. Location of the chelatingligand purple sweet potato extract with the main content of anthocyanins occur inbond 3 ', 4' dihydroxy ring B or 3-Hydroxy 4-Carbonyl ring C., Research of utilization of plant extracts as a corrosion inhibitor recentlyincreased along with the increasing demand for the use of chemicals that areenvironmentally friendly. Utilization of plant extracts as a corrosion inhibitorbecomes important given the characteristics of environmentally friendly (greeninhibitor), easy availability, resources are abundant and renewable, the productionprocedure is simple, and the production costs are quite competitive. In thisresearch, experimental testing of the synergistic effects of new types inhibitor ieextract purple potato (Ipomoea batatas L.) which has the main content ofanthocyanin with commercial inhibitor-based amine (aniline) and with ascorbicacid inhibitors.The study aims to analyze the rate of corrosion and metal corrosioninhibition efficiency of steel (API 5L) in the produced water environment using amixed inhibitor purple sweet potato extract and commercial-based inhibitors ofamine (aniline). In addition, the corrosion rate analysis was also performed,inhibition efficiency, protection mechanisms and models of metal corrosioninhibition layer steel (API 5L) in the neighborhood of 3.5% NaCl using a mixedinhibitor purple sweet potato extract and ascorbic acid.Method of measuring the rate of corrosion and inhibition efficiency wasperformed using electrochemical polarization curves. Corrosion mechanismsinvestigated by Electrochemical Impedance Spectroscopy (EIS). To analyze themodel layer of inhibition were calculated using Fourier Transform Infra Red(FTIR) spectroscopy.The results showed that mixing purple sweetpotato extract has the abilityto synergistically with commercial inhibitor-based amine (aniline) in purplesweetpotato extract volume fraction of 25% with a yield of 82.14% inhibitionefficiency. For comparison, the same system using purple sweet potato extractonly produce inhibition efficiency of 68.30%, while the use of commercial-basedinhibitors of amine (aniline) alone resulted in inhibition efficiency of 74.88%.The addition of purple sweet potato extract volume of 1 mL to 4 mL intoascorbic acid inhibitors 10-4 M improving steel metal corrosion inhibitionefficiency (API 5L) in a solution of 3.5% NaCl of inhibition efficiency of 23.37%to 57.52%. The corrosion inhibitor mixture affect the anodic and cathodicpolarization curves so that it can act as a mixed inhibitor. Testing EIS shows thecorrosion process is controlled by the passivation mechanism indicated by anincrease in the surface resistance of corrosion.On the surface layer of a process of adsorption and formation of organochelates (flavonoids) in which the metal purple sweet potato extract with the maincontent of anthocyanins act as forming metal-chelated. Location of the chelatingligand purple sweet potato extract with the main content of anthocyanins occur inbond 3 ', 4' dihydroxy ring B or 3-Hydroxy 4-Carbonyl ring C.]"

"ABSTRAKSenyawa Annonaceous acetogenin (asetogenin) dari daun sirsak telah terbukti memiliki sifat antikanker. Gugus asetogenin terdiri dari berbagai senyawa, salah satunya adalah Annonacin yang banyak terdapat di bagian daun tanaman sirsak. Adapun tujuan dari isolasi ini adalah untuk mendapatkan senyawa annonacin yang dapat digunakan sebagai standar untuk penelitian lebih lanjut. Isolasi annonacin terdiri dari tiga tahap yaitu maserasi, fraksinasi, dan isolasi. Pelarut yang digunakan antara lain etanol, etil asetat, heksana, kloroform, dan air. Hasil isolasi tersebut diuji dengan menggunakan kedde reagent untuk mengetahui ada atau tidaknya gugus lakton serta jumlah konsentrasi lakton yang dikandung. Hasil uji reagen kedde menunjukkan adanya gugus lakton dengan perubahan warna menjadi pink-ungu. Jumlah konsentrasi lakton terkandung dari F4.4 241,86 mg/gr. Sitotoksisitas annonacin diuji menggunakan metode Brine Shrimp Test dengan menghitung LC50. Didapat nilai LC50 sebesar 1,04 ppm. Analisis kualitatif hasil isolasi dilakukan menggunakan HPLC dan LC-MS menghasilkan terdapat senyawa annonacin dari F4.4 dengan berat molekul 597,23.

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ABSTRACT

Compounds of Annonaceous acetogenin (asetogenin) from soursop leaf has been shown to have anticancer properties. Asetogenin group consists of a variety of compounds, one of which is that many Annonacin located on the leaves of the soursop plants. The purpose of isolation is to get annonacin compounds that can be used as a standard for further research. Isolation of annonacin consists of three phases, namely maceration, fractionation, and isolation. Solvents used include ethanol, ethyl acetate, hexane, chloroform, and water. isolation results were tested using kedde reagent to determine the presence or absence of the lactone group and the number concentration of lactones contained. Kedde reagent test results indicate the presence of the lactone group to change into a pink-purple color. Total concentrations of F4.4 lactone contained 241.86 mg / g. Annonacin cytotoxicity was tested using Brine Shrimp Test method by calculating the LC50. Obtained LC50 values of 1.04 ppm. Qualitative analysis of the results was performed using HPLC isolation and LC-MS produces compounds contained annonacin F4.4 with a molecular weight of 597.23."

"Kebutuhan akan inhibitor korosi ramah lingkungan semakin berkembang, sehingga penelitian untuk mencari alternatif ekstrak tumbuhan sebagai inhibitor korosi semakin meningkat. Kayu secang dipercaya memiliki kandungan antioksidan yang dapat berperan dalam menghambat laju korosi yang pada material. Penelitian ini dilakukan untuk melihat efek penambahan ekstrak Kayu Secang (KS) terhadap laju korosi dari Baja API 5L X52 dalam Larutan 3,5% NaCl dan juga melihat sifat sinergis inhibitor saat ekstrak KS dikombinasikan dengan ekstrak Kubis Merah (KM) yang sebelumnya telah dilaporkan efektif sebagai inhibitor korosi.Beberapa pengujian dilakukan untuk mengevaluasi KS sebagai inhibitor korosi. Metode Polarisasi dan EIS digunakan untuk melihat efektifitas ekstrak KS dan kombinasinya dengan ekstrak KM sebagai inhibitor korosi dengan variasi konsentrasi yang ditambahkan. FTIR digunakan untuk mengkarakterisasi gugus fungsi yang terkandung dalam ekstrak KS dan KM. Model adsorpsi isotherm digunakan untuk melihat mekanisme adsorpsi dari ekstrak.Dari hasil Polarisasi menunjukan penambahan ekstrak KS akan menurunkan laju korosi dari 0,172 mm/tahun menjadi 0,04 mm/tahun hingga konsentrasi 0,75 ml dalam 200 ml 3,5% NaCl, dan pengujian EIS mendukung hasil tersebut. Pengabungan ekstrak KS dengan KM menunjukan efek anti-sinergi melihat dari nilai sinergistik parameter yang didapat <1. Peningkatan efisiensi inhibisi pada komposisi 0,1 ml dan 0,2 ml KS dalam 2,5 ml KM, diperkirakan karena ekstrak yang ditambahkan belum mencapai titik optimum.Hasil FTIR menunjukan ekstrak KS memiliki gugus C=O yang berperan dalam proses adsorpsi dan gugus ?OH (hydroxil) yang menunjukan sifat antioksidan. Ekstrak KS dan juga campurannya teradsorpsi mengikuti model Langmuir isotherm dimana adsorpsi yang terjadi adalah monolayer dan tidak ada reaksi antar molekul. Nilai energi bebas menunjukan bahwa proses adsorpsi terjadi secara spontan dan jenis ikatan yang terjadi dalam proses adsorpsi adalah secara fisik/physicsorption dengan nilai -20,79 KJ/mol untuk ekstrak KS, dan -7,08 KJ/mol untuk Ekstrak KS+KM

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The needs of green corrosion inhibitors is growing, thus searching for the alternative plants extract to be used as corrosion inbitor is increasing. Caesalpinia sappan L (KS) believed to contain antioxidant that may play role in inhibiting the corrosion rate of material. This study was conducted to understand the inhibitive properties owned by the extract of KS on the API 5L X52 Material in 3.5%NaCl and to assess the sinergistic effect when KS is combined with Red Cabbage (KM) extract which already proven as alternative corrosion inhibitor.

Several tests were conducted to evaluate KS as green corrosion inhibitor. Tafel Polarization and EIS methods were used to assess the effectiveness of KS and its combination with KM as corrosion inhibitor at various concentration in 3.5% NaCl. FTIR method was used to characterize the functional groups contained in the extract. Adsorption isotherm was used to recognize the adsorption mechanism of the extracts.

The polarization results shows the inhibitive properties of KS thus reduce the corrosion rate of material from 0.172mm/year to 0.04mm/year with addition of 0.75ml of KS in 200ml 3.5%NaCl, meanwhile EIS result supports the polarization results. Mixing of KS and KM shows anti-synergistic effect, which shown on synergistic parameter value <1 for any volume addition of KS. An increase in inhibition efficiency on 0.1ml and 0.2ml KS composition of the mixture is expected due the mixture has not reached the critical point.

While FTIR results show KS and KM both has a C = O functional groups that play a role in the adsorption process and the -OH (hydroxil) which shows antioxidant properties. From the verification plot of several isotherm models, the KS extract and its mixture follows Langmuir Isotherm, which mean the inhibitive layer adsorbed is considered monolayer and there is no reaction between the active molecules. Thus from the calculation of adsorption free energy we have -20.79KJ/mol for KS and - 7.08KJ/mol, thereof the adsorption process considered as physicsorption and the adsorption occurs due to electrostatic bond. The minus (-) sign indicates the adsorption process is spontaneous."

"Pada penelitian terdahulu telah dilaporkan bahwa ekstrak etanol daun beligo (Benincasa hispida) yang diekstrak dengan metode maserasi diketahui memiliki efek inhibisi terhadap α-glukosidase (80,42% pada fraksi etil asetat). Tujuan penelitian ini adalah untuk memperoleh fraksi daun beligo teraktif sebagai inhibitor α-glukosidase dan memisahkan komponen aktifnya. Daya inhibisi ekstrak daun beligo yang diekstrak menggunakan metode soxhlet pada fraksi etanol, air, dan etil asetat, mengalami peningkatan seiring bertambahnya konsentrasi ekstrak. Pada konsentrasi 300 ppm ekstrak daun fraksi etil asetat memiliki daya inhibisi paling besar yaitu sebesar 99,46% dan IC50 sebesar 125,18 ppm. Hasil pada fraksi etil asetat paling baik dibandingkan dengan hasil fraksi etanol (78,93% dan IC50 sebesar 169,04 ppm) dan fraksi air (63,73% dan IC50 sebesar 257,53 ppm) . Pemisahan komponen aktif dari fraksi etil asetat dengan menggunakan KLT dan kromatografi kolom dengan campuran etil asetat dan n-heksana (1:4) menghasilkan beberapa spot pada fraksi 2, 3, 4, 5, 6, 7, dan 9. Fraksi dengan nilai Rf yang dapat diterima adalah fraksi 3, 5, 6, 7, dan 9 (0,67; 0,74; 0,7; 0,73; 0,54; 0,3; 0,38; dan 0,44). Spektrum IR pada fraksi 5 menghasilkan peak-peak yang menandakan adanya gugus O-H, C=O, C-H, C=C dan C-O.

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In previous study reported that ash gourd or beligo (Benincasa hispida) leaves obtained by maceration method are known to have inhibition effects (80,42% in ethyl acetate fraction). The purpose of this study was to obtain the most active fraction of ash gourd leaves extract as α - glucosidase inhibitors and separating the active components of these fractions. Percent inhibition Benincasa hispida fraction of ethanol extract of leaves, water, and ethyl acetate were extracted by soxhlet metode increased with increasing concentrations of the extract. At concentration of 300 ppm, the fraction of ethyl acetate from extract of the leaves have a greatest inhibitory effect is equal to 99,46%and IC50 at 125,18 ppm. Results of the ethyl acetate fraction is best compared with the results of ethanol fraction (78.93 % and IC50 is 169.04 ppm) and water fraction (63.73 % and IC50 is 257.53 ppm). Separation of chemical components of ethyl acetate fraction by TLC with eluent ratio mixture of ethyl acetate and n-hexane (1:4) generate some spots on 2nd, 3rd, 4th, 5th, 6th, 7th, and 9th. Fraction with Rf value that can be accepted are 3rd, 5th, and 6th fraction (0,67; 0,74; 0,7; 0,73; 0,77; 0,54; dan 0,76). IR spectrum of 5th fraction obtained from column chromatography indicated that the active component of beligo leaves extract had C=O, C-O, C=C, and O-H groups.

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