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"ABSTRACTIonic liquids are considered as an ideal alternative to volatile organic solvents and chemical industries in the future, because they are non-volatile. Ionic liquids are also considered as new novel chemical agents and widely regarded as a greener alternative to many commonly used solvents. Ionic liquids have been studied for a wide range of synthetic applications and have attracted considerable interest for use as electrolytes in the areas of organic synthesis, catalysis, solar cell, fuel cells, electrodeposition and supercapacitors. However, some ionic liquids suffer from more or less somedrawbacks such as toxicity, preparation and high cost in the process for use. Most recently, three types of ionic liquids are attracted much attentions specifically traditional ionic liquid, protic ionic liquid and deep eutectic solvent, where their preparation, mechanism and limitation were differentiated. However, those liquids are having their own advantages and limitations based on applications. Traditional ionic liquid and protic ionic liquid are highly cost and toxic for applied engineering research, but they consist of micro-biphasic systems composed of ionic compounds whichhave more varieties in the applications. The deep eutectic solvent is very economic for large-scale possessing but there are only limited ionic mixtures to certain application such as electrochemistry."

"Ekstraksi daging buah mahkota dewa Phaleria macrocarpa menggunakan pelarut cairan ionik ionic liquid belum pernah dilakukan. Akhir-akhir ini, cairan ionik populer sebagai pelarut ekstrasi tanaman karena terbukti menghasilkan hasil ekstraksi yang memuaskan dibandingkan dengan metode konvensional. Disebutkan pada penelitian sebelumnya bahwa salah satu metode ekstraksi yang sesuai untuk mengekstraksi buah mahkota dewa adalah dengan menggunakan Microwave Assisted Extraction MAE. Diharapkan ekstraksi daging buah P. macrocarpa yang menggunakan cairan ionik dan MAE juga dapat memberikan hasil yang memuaskan dengan dilakukannya optimasi pada kondisi-kondisi ekstraksi serta membandingkan hasilnya dengan ekstraksi konvensional. Pelarut cairan ionik yang diuji ada 3 yaitu [BMIM] Br, [BMIM] Cl, dan [BMIM] BF4. Hasil pemilihan pelarut yang dipilih adalah [BMIM] BF4 yang akan digunakan dalam optimasi dan diuji kadar total fenoliknya dengan metode Folin Ciocalteu. Setelah didapat kondisi optimum, aktivitas antioksidan diuji dengan metode DPPH menggunakan microplate reader. Hasil dari optimasi adalah dengan konsentrasi tertinggi, rasio pelarut-sampel tertinggi dan waktu ekstraksi yang tidak berpengaruh pada hasil ekstraksi, didapat kadar total fenolik maksimum sebesar 191,72 mg GAE/g serbuk. Hasil ini terbukti lebih tinggi dibanding metode ekstraksi konvensional. Hasil ekstraksi dalam kondisi ini dimaksimalkan kembali hasilnya dengan dilakukan pretreatment menggunakan urea agar senyawa fenolik yang diekstraksi mendapatkan hasil yang lebih banyak. Percobaan setelah optimasi selesai, dilakukan dengan membandingkan suatu kondisi ekstraksi dengan pretreatment menggunakan urea. Hasil yang didapat adalah ekstraksi yang telah terlebih dahulu diberikan pretreatment menghasilkan kadar total fenolik yang lebih besar dibandingkan dengan tanpa pretreatment.

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The use of ionic liquids as solvent to extract flesh of fruit of mahkota dewa Phaleria macrocarpa has not been studied yet. In the last decades, ionic liquids was popular as solvent for extracting plant material because of its higher extraction yield compared to conventional methods. It is said in one previous research, that one of many suitable extraction methods to extract flesh of fruit of mahkota dewa is Microwave Assisted Extraction MAE. We hypothesized that plant extraction using ionic liquids in MAE method would give satisfying results by optimizing extraction conditions and comparing the result with conventional extraction method. Three different kinds of ionic liquids, BMIM Br, BMIM Cl, and BMIM BF4 were investigated. The ionic liquids, BMIM BF4 were elected and further used in optimization and tested for its total phenolic content TPC with Folin Ciocalteu method. Afterwards, antioxidant activity were tested by DPPH method in optimum condition. Both tests used microplate reader. Maximum total phenolic content were obtained with higher solvent concentration, higher solvent sample ratio, and an insignificant extraction time with 191,717 mg GAE g plant powder. This result proves that it is higher than the conventional extraction method. The extraction yield were maximized by applying pretreatment with urea to obtain higher total phenolic content after extraction. After optimization experiment were done by comparing the extract from optimum condition without urea, with after urea pretreatment extract. The result shows that pre treated sample with urea pretreatment gives higher total phenolic content compared with non pretreated sample."

"Daun cincau hijau Cyclea barbata Miers. merupakan tanaman yang berasal dari Indonesia yang dipercaya memiliki khasiat sebagai antiinflamasi. Adapun senyawa pada daun cincau hijau yang dapat berperan sebagai antiinflamasi adalah flavonoid. Proses inflamasi dipengaruhi oleh dua jalur yaitu lipoxygenase LOX dan cylooxygenase COX . Tujuan penelitian ini adalah mengetahui kondisi optimum untuk ekstraksi daun cincau hijau dengan metode ionic liquid-microwave assisted extraction IL-MAE serta mengetahui penghambatannya terhadap aktivitas lipoksigenase. Spektrofotometer UV-Vis digunakan untuk penetapan kadar flavonoid total dan uji penghambatan lipoksigenase. Kondisi optimum yang diperoleh berada pada rasio simplisia banding pelarut 1:40 b/v , waktu ekstraksi 15 menit, dan konsentrasi [Bmim][Br] 2 mol/L dimana diperoleh kadar flavonoid total sebanyak 31,25 mgQE/1 g ekstrak kental dengan penghambatan aktivitas lipoksigenase tertinggi 69,29 . Hasil pengujian menunjukkan bahwa kondisi optimum didapatkan kadar flavonoid total tertinggi dan terdapat hubungan yang signifikan antara peningkatan kadar flavonoid total dengan peningkatan penghambatan aktivitas lipoksigenase.

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Green grass jelly leaf Cyclea barbata Miers. is a plant from Indonesia that is believed to have anti inflammatory activity. The compound in the leaves of green grass jelly that can act as an anti inflammatory is flavonoids. There are two pathways in which the inflamatory process can occur, lipoxygenase LOX and cylooxygenase COX . The purpose of this research was to find the optimum condition in green grass jelly extraction using the ioninc liquid microwave assisted extraction IL MAE and to find its inhibition activity of lipoxygenase. Spectrophotometry UV Vis was used to determined the total flavonoid content and its inhibition activity of lipoxygenase. The optimum condition was achieved using the simplicia and solvent ratio of 1 40 w v , with 15 minutes of extraction time, and the concentration of Bmim Br 2 mol L. The total flavonoid content obtained was 31.25 mgQE 1 g of viscous extract and the highest inhibition of lipoxygenase activity was 69.29 . Based from the results can be concluded that the total flavonoid content was the highest at the optimal conditions, and there was a linear corelation between the levels of flavonoids and inhibition activity of lipoxygenase."

"The book examines water as a solvent for gases, non-electrolytes, and electrolytes and reviews the properties, sizes and thermodynamics of isolated and aqueous ions, as well as their interactions, including those of polyelectrolytes. The effects of ions on water structure, including those on solvent dynamics and certain thermodynamic quantities, are presented. This volume investigates water surfaces with its vapour, with another liquid, and with a solid, as well as the effects of solutes, including simple ions and the water-miscible non-electrolytes. Surfaces are relevant to biomolecular and colloidal systems and the book discusses briefly surfactants, micelles and vesicles. Finally, the book concludes with a review of the various biophysical implications involving chaotropic and kosmotropic ions in homogeneous solutions and the Hofmeister series for ions concerning biomolecular and colloidal systems and some aspects of protein hydration and K+/Na+ selectivity in ion channels. "

"This book of general analytical chemistry, as opposed to instrumental analysis or separation methods, in aqueous solutions is focuses on fundamentals, which is an area too often overlooked in the literature. Explanations abound of the chemical and physical principles of different operations of chemical analysis in aqueous solutions. Once these principle are firmly established, numerous examples of applications are also given."

"Indonesia merupakan negara yang memiliki karakteristik udara yang cenderung lembap, kelembapan yang cukup tinggi dapat memiliki berbagai macam masalah. Oleh karena itu untuk mengurangi kelembapan udara tersebut digunakanlah dehumidifikasi sehingga dapat menghasilkan kondisi udara yang nyaman dan sesuai dengan yang diinginkan. Dehumidifier yang digunakan pada penelitian ini yaitu desiccant dehumidifier dengan packed bed. Desiccant dehumidifier merupakan dehumidifier yang menggunakan ionic liquid sebagai cairan untuk menyerap uap air pada udara. Penelitian ini menggunakan studi eksperimental untuk mengetahui rasio kelembapan terhadap udara agar dapat mengetahui karakteristik ionic liquid. Hasilnya terdapat sebesar 0,68 g/kg-0,93 g/kg uap air yang dapat diserap oleh Ionic liquid dalam penelitian ini yang merupakan hasil dari proses dehumidifikasi.

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Indonesia is a country that has air that tends to be humid, the humidity which was high enough also cause a number of problems. Which is why to counter those problems people mostly using dehumidification to produce a desired air condition which is comfortable and suitable. Dehumidifier that is used for this research called desiccant dehumidifier using packed bed. Desiccant dehumidifier is a type of dehumidifier that used ionic liquid as a solution to absorb water vapor in the air. The research used an experimental study to know the humidity ratio for air in order to know the characteristics of ionic liquid. The result are as much as 0,68 g/kg-0,93 g.kg water vapor could be absorbed in the ionic liquid and there is a process of dehumidification."

"Indonesia merupakan negara yang memiliki kelembaban yang cukup tinggi dan cuaca yang cukup panas, oleh karena itu negara Indonesia membutuhkan alat pengering udara agar kelembaban dapat turun sampai titik nyaman untuk manusia. Sistem pengering udara lebih ramah lingkungan sebagai teknologi alternatif untuk proses penurunan kelembaban, terutama dalam kasus dengan muatan laten yang tinggi untuk menjaga kualitas udara. Teknologi ini lebih efisien di iklim panas dan lembab seperti Indonesia. Penelitian ini melakukan penyelidikan eksperimental untuk mengetahui rasio kelembapan terhadap udara untuk mengetahui karakteristik cairan ionik menggunakan alat pengering udara. Cairan ionik dalam percobaan ini akan melewati bilah kayu yang berfungsi sebagai alat penukar kalor, cairan ionik akan bersirkulasi selama kurang lebih dua jam. Eksperimen ini memvariasikan laju aliran cairan ionic dari 200 sampai 600 L/h dan didapatkan juga hasil rasio kelembaban yaitu -0.10 sampai -0.56 g/kg. Setiap kenaikan laju aliran besarannya juga akan semakin meningkat. Konsumsi energi di dunia meningkat setiap tahunnya, terutama dalam industri dan sektor transportasi. Konsumsi energi yang besar ini menghasilkan emisi karbon dioksida yang berbahaya bagi lingkungan dan kesehatan manusia. Salah satu cara untuk mengurangi konsumsi energi dan emisi karbon dioksida adalah dengan menggunakan sistem HVAC yang efisien.  Saat ini, banyak penelitian dilakukan untuk mencari solusi sistem HVAC yang lebih efisien. Salah satu solusi yang sedang dikembangkan adalah penggunaan liquid desiccant. Liquid desiccant dapat digunakan untuk menghilangkan kelembaban dari udara, yang dapat mengurangi beban pada sistem pendingin ruangan dan menghemat energi.  Namun, penggunaan liquid desiccant masih belum banyak digunakan di sektor HVAC.

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Indonesia is a country with relatively high humidity and hot weather, therefore, it requires air drying equipment to reduce humidity to a comfortable level for humans. Air drying systems are more environmentally friendly as an alternative technology for humidity reduction, especially in cases with high latent loads to maintain air quality. This technology is more efficient in hot and humid climates like Indonesia. This research conducted experimental investigations to determine the humidity ratio to air to understand the characteristics of ionic liquid using an air drying apparatus. In this experiment, the ionic liquid will pass through wooden blades that function as a heat exchanger, and the ionic liquid will circulate for approximately two hours. The experiment varied the flow rate of the ionic liquid from 200 to 600 L/h, and the resulting humidity ratio ranged from -0.10 to -0.56 g/kg. With an increase in the flow rate, the magnitude of the humidity ratio also increased. Energy consumption worldwide is increasing every year, especially in industries and the transportation sector. This high energy consumption results in harmful carbon dioxide emissions that negatively impact the environment and human health. One way to reduce energy consumption and carbon dioxide emissions is by using efficient HVAC (Heating, Ventilation, and Air Conditioning) systems. Currently, extensive research is being conducted to find more efficient HVAC system solutions. One promising solution being developed is the use of liquid desiccants. Liquid desiccants can remove moisture from the air, reducing the load on the room's cooling system and saving energy. However, the use of liquid desiccants is still not widely adopted in the HVAC sector."

"Stigmasterol glukosida (STG) ditemukan di karantin, yang mengandung campuran STG dan beta-sitosterol glukosida (1: 1), dan terdapat pada buah pare (Momordica charantia L.) (BP). Tujuan penelitian ini adalah untuk mengoptimalkan ekstraksi STG dari BP dengan menggunakan metode ekstraksi berbantuan ultrasonikasi-cairan ionik (IL-UAE) diikuti dengan ekstraksi cair-cair. Optimasi bertujuan untuk mendapatkan kandungan STG tertinggi dan meliputi optimasi jenis pelarut, konsentrasi pelarut, waktu ekstraksi, dan rasio pelarut terhadap sampel, yang dianalisis dengan metodologi permukaan respons (RSM). Ekstrak yang diperoleh diukur dengan kromatografi cair kinerja tinggi (KCKT). Metode UAE dibandingkan dengan metode ekstraksi maserasi. Hasil penelitian menunjukkan bahwa kondisi ekstraksi optimum menggunakan pelarut 1-butil-3-methylimidazolium tetrafluoroborate (BMIMBF4) dengan konsentrasi 0,61 M, waktu ekstraksi 47,43 menit, dan perbandingan pelarut terhadap sampel 10: 1. Kondisi optimum menghasilkan kandungan STG aktual sebesar 1,90 mg/g, yang mendekati kandungan RSM prediksi optimal (1,95 mg/g) untuk ekstraksi cair. Setelah ekstraksi cair-cair, kandungan STG meningkat menjadi 4,96 mg/g. Metode ekstraksi UAE dan maserasi memperoleh jumlah STG masing-masing 1,05 mg/g dan 1,44 mg/g. Penelitian ini menunjukkan bahwa dibandingkan dengan metode ekstraksi maserasi, ekstraksi IL-UAE memberikan hasil STG yang lebih tinggi.

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Stigmasterol glucoside (STG) is found in charantin, which contains a mixture of STG and beta-sitosterol glucoside (1:1), and is present in bitter melon fruit (Momordica charantia L.) (BMF). The study aim was to optimise extraction of STG from BMF by using an ionic liquid–ultrasonication-assisted extraction (IL-UAE) method followed by liquid–liquid extraction. The goal of optimisation was to obtain the highest STG content and involved optimising the solvent type, solvent concentration, extraction time and solvent-to-sample ratio, which were analysed by response surface methodology (RSM). The obtained extract was measured by high-performance liquid chromatography. The UAE method was compared with a maceration extraction method. The results show that the optimum extraction conditions were using 1-butyl-3-methylimidazolium tetrafluoroborate (BMIMBF4) as a solvent with concentration of 0.61 M, an extraction time of 47.43 minutes and a solvent-to-sample ratio of 10:1. The optimum conditions produced an actual STG content of 1.90 mg/g, which was close to the optimum predicted RSM content (1.95 mg/g) for liquid extraction. After liquid–liquid extraction, the STG content increased to 4.96 mg/g. The UAE and maceration extraction methods obtained STG amounts of 1.05 mg/g and 1.44 mg/g, respectively. This study showed that compared with the maceration extraction method, IL-UAE extraction provided a higher STG yield."