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31	Chemistry	ABS-620
Development of Mobile Game Base Learning on Buffer Solution to Improve Student Performance Dr. Ucu Cahyana, M.Si, Dr. Maria Paristiowati, M.Si, Winda Eka Pratiwi, S.Pd, Putri Ayu Zahari, S.Pd UNIVERSITAS NEGERI JAKARTA Abstract This study aims to develop innovative learning media that is mobile. Learning and knowing the quality of media are produced and see the feasibility of media to be used in learning on buffer solutions. This research was conducted at SMAN 107 Jakarta and SMAN 42 Jakarta starting in January 2018 until May 2018. The research method used is Research and Development which includes four stages, namely: (1) needs analysis, (2) development of mobile learning media, (3) Feasibility and trial test. Media that generates an android-based smartphone (smartphone) application called ChemBuff is 167MB compatible on Android devices up to v.7.1 Nougat with features such as material, video and educational features about the solution buffer. Based on the feasibility test It can be concluded that the mobile learning media that has been developed is feasible and practical for use in learning material buffer solutions. The test solution is that there is a very significant difference between the pre-test and post-test results. Keywords: Mobile Learning, Buffer Solution PermaLink | Plain Format | Corresponding Author (Syifa Fauziyah)

32	Chemistry	ABS-883
Developing laboratory tool for pre-service chemistry teacher: Low-cost spectrophotometers project Ari Syahidul Shidiq, Anna Permanasari and Hernani 1Departemen Pendidikan IPA, Sekolah Pascasarjana, Universitas Pendidikan Indonesia, Jl. Dr. Setiabudi no 229, 40154, Bandung, Indonesia Abstract Spectroscopy is part of modern chemistry, which allows chemists to study the structure and properties of atoms and molecules. Unfortunately, many pre-service chemistry teachers are not usually introduced to the basic principles behind this technique. The study aims to develop simple and low-cost spectrophotometers. Project-based learning was used in this study. The experiments fit well into an analytical chemistry course and take a standard (1 h) lab period. Low-cost spectrophotometers made by pre-service chemistry teacher have a fairly good sensitivity compared to modern spectrophotometers. Pre-service chemistry teachers have better knowledge about the spectroscopy, and the basic principles of the instrument after developing Low-cost spectrophotometers. In addition, the project activities also enhance the creative thinking skills of the pre-service chemistry teacher Keywords: Laboratory tool, Spectroscopy, spectrophotometers PermaLink | Plain Format | Corresponding Author (ARI SYAHIDUL SHIDIQ)

33	Chemistry	ABS-885
Chemistry sustainable curriculum: pre-service chemistry teacher learning difficulties in hydrolysis Ari Syahidul Shidiq (a), Sri Yamtinah (b) and Masykuri (b) (a)Departemen Pendidikan IPA, Sekolah Pascasarjana, Universitas Pendidikan Indonesia, Jl. Dr. Setiabudi no 229, 40154, Bandung, Indonesia (b) Program Pendidikan Kimia, Universitas Sebelas Maret, Jl. Ir. Sutami No. 36A, Kentingan, 57126, Surakarta, Indonesia Abstract Identifying students learning difficulties and finding the effective ways of addressing them have been the two of major concerns in chemistry education. The aims of this study were to identify students learning difficulties in hydrolysis. A formative assessment post-test was administered to 151 students in grade 11 using testlet instrument to find out their learning difficulties. Its findings could provide the teachers with sufficiently valuable information required in order to adapt their teaching methods to the students needs for chemistry sustainable curriculum development. The instrument contained 30 items distributed across three themes: scientific reasoning, numeracy and scientific language literacy. The results indicated that the students held learning difficulties on numeracy. The students had difficulties in controlling and interpreting the data. The possible uses of teaching methods, targeted remedial teaching and testing using testlet instrument for addressing students learning difficulties were discussed Keywords: sustainable development education, pre-service chemistry teacher, hydrolysis PermaLink | Plain Format | Corresponding Author (ARI SYAHIDUL SHIDIQ)

34	Chemistry	ABS-635
Synthesis of Silicalite-1 Zeolite using Silica from Elephant Grass (Pennisetum purpureum) Citra Deliana Dewi Sundari1, Soni Setiadji2, Ani Andriani2, Eko Sumiyanto2 and Atthar Luqman Ivansyah3 1Department of Chemistry Education, UIN Sunan Gunung Djati Bandung, Jl. Cimincrang, Cimenerang, Panyileukan, Bandung, West Java, 40292, Indonesia. 2Department of Chemistry, Faculty of Science and Technology, UIN Sunan Gunung Djati Bandung, Jl. A.H. Nasution No.105 Bandung, West Java, 40614, Indonesia. 3Master Program in Computational Science, Faculty of Mathematic and Natural Science, Institut Teknologi Bandung, Jl.Ganesha No. 10, Bandung, West Java, 40132, Indonesia Abstract Silicalite-1 is a type of zeolite with no aluminum content and is hydrophobic. This zeolite can be synthesized from various types of silica. Elephant grass (Pennisetum purpureum) is one of the potential agricultural wastes that has a fairly high silica content that can be used for zeolite synthesis. In this study, silicalite-1 zeolite was synthesized using silica extracted from elephant grass and tetrapropilammonium bromide (TPABr) templates. Silica samples extracted from elephant grass have 71.91% amorphous SiO2 content. Silicalite-1 zeolite was synthesized with mole ratio of 1SiO2 : 0.527TPABr : 0.395Na2O : 98.45 H2O, using hyrothermal method at 180°C for 24 hours in a stainless steel-teflon lined autoclave. The resulting silicalite-1 samples were confirmed by X-Ray Diffraction (XRD) and showed 2θ which was typical for silicalite-1 i.e. 8.02°, 8.93°, 23.09°, and 23.98°. The results of Scanning Electron Microscopy (SEM) show that silicalite-1 zeolite has hexagonal crystals with 43.36 µm size as a result of the calculation using the Schrerrer method. Keywords: silica isolation; amorphous silica; elephant grass; tetrapropilammonium bromide; silicalite-1 zeolite PermaLink | Plain Format | Corresponding Author (Citra Deliana Dewi Sundari)

35	Chemistry	ABS-142
The making of metal coating props oriented chemical representation Dian Mayangsari(a), F S Irwansyah(a*), Ida Farida(a) UIN Sunan Gunung Djati Bandung *ferli[at]uinsgd.ac.id Abstract This research used research and development method with stages of analysis, design and development to produce props of metal coating plates oriented chemical representation. This research is driven by the importance of a chemical learning medium that can present macroscopic, submicroscopic and symbolic representations on metallic coating materials so that material can be delivered well to students. Based on the results of the research, the product is obtained in the form of metal coating props with the characteristics of combining macroscopic, submicroscopic and symbolic representations with guidebooks and worksheets. Validation results indicate that the product is valid with the acquisition of the value of r-count on props of 0.92. Keywords: props; chemical representation; metal coating PermaLink | Plain Format | Corresponding Author (Ferli Septi Irwansyah)

36	Chemistry	ABS-661
VETIVER OIL GAS CHOROMATOGRAPHY PROFILE (Vetiveria Zizanioides L.) FROM GARUT REGENCY Ardi Rustamsyah1*, Farid Perdana1, Anggana1 1. Program Studi Farmasi, Fakultas Matematika dan Ilmu Pengetahuan Alam Univesitas Garut Jl. Jati No. 42 B Tarogong Garut, Jawa Barat *ardi[at]uniga.Ac.id Abstract Plant diversity in Indonesia is a very big asset especially volatile oil content derived from various types of crops in Indonesia. Essential oils or also called volatile oil or essential oil is the term used for volatile oil. Grass essential oil of vetiver (Vetiveria Zizanioides L.) Obtained by steam destilation. Gas chromatography mass spectroscopy (GC-MS) is a dynamic method for the separation and detection of comfound-volatile compounds in a mixture. The purpose of this study was to determine the quality of vetiver oil from Garut Regency from two different places using gas coromatography - mass spectroscopy (GC-MS). Based on the results of gas chromatography - mass spectroscopy, the essential oil of H. Suganda fragrant roots identified 65 components or compounds, with the most dominant compound being isokhusenic acid, while the essential oils of vetiver campoeng garoet identified 79 components or compounds, with the most dominant compounds (3E) -5-Isopropyliden-6-methyl-3,6,9-decatrien-2-one. Keywords: Keywords: Vetiveria zizanioides L., fragrant root, essential oil. PermaLink | Plain Format | Corresponding Author (Farid Perdana)

37	Chemistry	ABS-151
The Making Electronic Visualization Modules Chemical Equilibrium Process Based on POE (Predict-Observe-Explain) Rita Sahara (a), Cucu Zenab Subarkah (a*), Saepudin Rahmatullah (a) Department of Chemical Education, UIN Sunan Gunung Djati Bandung, Jalan A. H. Nasution No. 105 Cibiru Bandung 40614 Indonesia *zenabsc[at]uinsgd.ac.id Abstract The limitation in connecting the three levels of chemical representation is a major factor in the difficulty of learning the concept of chemical equilibrium. Computer-based molecular visualization and integrated three-dimensional animation can help students have representational capabilities by providing opportunities to present several levels simultaneously in various formats such as video, animation, and simulation. This study aims to create an e-module visualization of POE-based chemical equilibrium processes (Predict-Observe-Explain) which includes sub-concepts of dynamic equilibrium, homogeneous and heterogeneous equilibrium, and factors that influence chemical equilibrium. The three main activities in this e-module are predicting, observing and explaining. The e-module was created using the Design Based Research method with ADD design (Analysis, Design, Development) which was validated by two material expert lecturers and two multimedia expert lecturers producing an overall average calculation of 0.87 while the results of the feasibility test conducted at ten students show a percentage of 98.11%. This shows that this e-module is very suitable to be used as teaching material. Keywords: e-module visualization; chemical equilibrium; POE learning model (Predict-Observe-Explain) PermaLink | Plain Format | Corresponding Author (Rita Sahara)

38	Chemistry	ABS-664
Identification of Glibenclamide in Antidiabetic Jamu by High Performace Liquid Chromatography Method: Study in Purwokerto, Indonesia Pri Iswati Utami (a), Dede Firman (a), Asmiyenti Djaliasrin Djalil (a*) a) Faculty of Pharmacy, Universitas Muhammadiyah Purwokerto Jalan Raya Dukuhwaluh, Kembaran, Purwokerto, Indonesia *asmiyentidjaliasrindjalil[at]ump.ac.id Abstract Adulteration of synthetic pharmaceutical drugs in jamu is prohibited by law in Indonesia. Glibenclamide is one of the drugs commonly added to jamu. The purpose of this study was to obtain a valid high performance liquid chromatography (HPLC) method for qualitative and quantitative analysis of glibenclamide in antidiabetic jamu. HPLC separation was carried out with a Kromasil 100 C18 column (150 x 4.6 mm i.d, 5 μm particle size) using methanol: water (75:25) v/v as the mobile phase at a flow rate of 0.5 mL/min, UV detection was set at 301 nm. There was no potential interference from other compounds at the glibenclamide retention time (retention time of 5.10 minutes). The method has good linearity (r = 0.9936) in the range 10-50 mcg/mL. The detection limit of the method was 6.21 mcg/mL while the quantitation limit was 20,71 mcg/mL. The relative standard deviation (RSD) of intraday precision was 1.923%. The average recovery using standard addition method was 100.65 ± 16.89%. The application of the HPLC method for the analysis of five antidiabetic jamu samples obtained from the market in Purwokerto showed that glibenclamide was detected in one sample with a level of 1.88 ± 0.25 mcg/g. Keywords: antidiabetic jamu, glibenclamide, HPLC, validation PermaLink | Plain Format | Corresponding Author (Pri Iswati Utami)

39	Chemistry	ABS-923
Chemistry Students’ Soft Skills Development through the integration of Think Pair Square (TPSq) in Socio Critical and Problem Oriented approach in Acid-Base Learning Tritiyatma Hadinugrahaningsih, Risky Amalia, Ella Fitriani, Yuli Rahmawati Universitas Negeri Jakarta, Chemistry Education Department, Faculty of Mathematics and Natural Sciences, Jalan Rawamangun Muka 13220, Jakarta, Indonesia Abstract This research aimed to develop the chemistry students’ soft skills students through acid-base learning by integrating Think Pair Square (TPSq) in socio critical and problem-oriented approach. The study involved 36 secondaty school students in year-11. The qualitative research methodology with interview, observation, and reflective journal were employed to understand the process and engage the participants. The issues of 1000mg vitamin C, “kangen water”, and infused water in relation to acid-base concept water were used to encourage students’ critical thinking in solve the problems. The results showed that students engaged and motivated in meaningful chemistry learning experiences, meanwhile the teacher were challenged in the role as facilitator. The students’ soft skills of collaboration and communication skills, critical and creative thinking skills were stimulated within the process. The students have learnt to reflect on their own values during debate in solving the problems. Finally, the learning experiences have challenges both students and teacher in reflecting on their roles to create challenging academic environment. Keywords: Socio Critical and Problem Oriented, acid base, think pair square (TPSq), soft skills PermaLink | Plain Format | Corresponding Author (Tritiyatma Hadinugrahaningsih)

40	Chemistry	ABS-159
Application of Green Chemical Concepts in the Synthesis of Sodium Lignosulfonate (SLS) Surfactant from Bagasse Rini Setiati1*, Septoratno Siregar2, Deana Wahyuningrum3, Ayu Listyani4 1Petroleum Engineering, FTKE, Universitas Trisakti, Jakarta, Indonesia 2 Petroleum Engineering, FTTM, Institut Teknologi Bandung, Bandung, Indonesia 3,4 Chemistry, FMIPA, Institut Teknologi Bandung, Bandung, Indonesia Abstract Green chemical is the designing of products and processes that minimize the use and generation of hazardous substances. Synthesis of Sodium Lignosulfonate (SLS) Surfactant can be processed from bagasse, waste of sugar cane. The aim of this study is to show that sodium lignosulfonate surfactant (SLS) can be made from bagasse using the Microwave-Assisted Organic Synthesis (MAOS) with the concept of green chemistry. Bagasse processing becomes SLS with hydrolysis and sulfonation process using microwave radiation. The process is closed system, for 1 hour, with a microwave power of 300 watts at 80oC. The process is using Microwave-Assisted Organic Synthesis (MAOS) which is equipped with chemical flask and condenser. Reagents are used fairly in small concentrations, 2% NaOH and 0.1 M sodium bisulfite. The result of synthesized SLS from bagasse is brown powder. The synthesized SLS product using Microwave-Assisted Organic Synthesis has been tested with Fourier Transform Infra Red (FTIR), consisting of Alkene, Sulfonate, Carboxylic Acids and Ester. This composition is similar to the composition of the commercial SLS standard which petroleum based, so it qualifies for surfactant injection in the EOR process. Green Chemical concepts can be applied in the Synthesis of Sodium Lignosulfonate Surfactant using Microwave Assisted Organic Synthesis. Keywords: bagasse, green chemical, microwave, synthesized surfactant PermaLink | Plain Format | Corresponding Author (RINI SETIATI)

41	Chemistry	ABS-415
Ab initio study of ethyl-p-methoxycinnamate and its derivatives as inhibitors of iron in acidic medium Saprizal Hadisaputra (a*), Agus Abhi Purwoko (a), Aliefman Hakim (a), Rahmawati (a), Lalu Rudyat Telly Savalas (a), Saprini Hamdiani (b) a) Chemistry Education Division, Faculty of Science Education, University of Mataram. b) Department of Chemistry, Faculty of Mathematics and Natural Science, University of Mataram. Abstract The efficiency of ethyl-p-methoxycinnamate and its derivatives as corrosion inhibitors of iron corrosion in acid environment has been studied to find the relationship between molecular structure parameters with the efficiency of corrosion inhibition. The MP2 perturbation theory was applied to calculate molecular structure and electronic parameters. Computational and experimental corrosion inhibition efficiency show that the electronic properties of molecules, including the orbital molecular frontier energy (HOMO and LUMO energy), ionization potential, electron affinity, electronegativity, softness, hardness, number of electron transfer from inhibitor to metal, and interaction energy have a strong relationship with inhibition performance. Furthermore, Fukui function obtained from natural bond orbital analysis was employed to study the interactions between inhibitors with iron metal in more detail. The presence of heteroatom and electron donor groups within the frameworks of inhibitors has a significant effect on corrosion inhibition performance. Keywords: ab initio, corrosion inhibition, ethyl-p-methoxycinnamate, inhibitor PermaLink | Plain Format | Corresponding Author (Saprizal Hadisaputra)

42	Chemistry	ABS-420
Being confident in basic chemistry laboratory activity through pre-lab demonstration videos: design and development Ella Fitriani, Maria Paristiowati, and Balqis Mukarromatunnisa Universitas Negeri Jakarta, Chemistry Education Department, Faculty of Mathematics and Natural Sciences, Jalan Rawamangun Muka 13220, Jakarta, Indonesia Abstract There are difficulties for first-year chemistry students to adapt to chemistry laboratory activity since they are lack of experience in their school. As a result, it affected their confidence and even their safety in the laboratory. One of the very basic skills in chemistry laboratory is the titration. This multi-year study aims to design and develop chemistry pre-laboratory demonstration videos to make students familiar with the skills before they start the laboratory activity. The data were collected by questionnaire, documentation, and interview. Based on the evaluation of users and experts, usability and feasibility of the videos were categorized very high. Moreover, corrections and suggestions are implemented to improve the chemistry pre-laboratory demonstration videos quality. Keywords: pre-laboratory; demonstration video; titration; basic chemistry PermaLink | Plain Format | Corresponding Author (Ella Fitriani)

43	Chemistry	ABS-676
AN EFFECTIVE ALTERNATIVE OF PRE-DAWN MEAL USING MILK KEFIR M Listiawati, T Kurniati, and N Windayani a) 1 Prodi Pendiidkan Biologi, 2Prodi Pendidikan Kimia, Fakultas Tarbiyah dan Keguruan, UIN Sunan Gunung Djati Bandung Jl. A.H. Nasution No. 105, Bandung 40614, Indonesia a)E-mail: nenengwinda.ftk[at]uinsgd.ac.id Abstract In this study, the nutritional composition of milk kefir cream and hunger resistance on its use as a menu of pre-dawn meal were examined. The pre-experimental design of intact group comparison was used on 34 research subjects. The experimental group (n = 17) treated pre-dawn meal using milk kefir cream and cereal while the control group used a complete per-dawn meal menu. The time of preparation, the implementation of the meal and hunger resistance were calculated and recorded. Based on the results of the study, in terms of methods, consuming 250 mL of milk kefir cream and cereal only takes about 7.9 minutes with a hunger resistance of up to 9.4 hours. With this composition and method, it is suggested that the results of this study can be useful to be an effective alternative of pre-dawn meal both in Ramadan and other Sunnah fasts. Keywords: pre-dawn meal, milk kefir, fasting, glycemic index PermaLink | Plain Format | Corresponding Author (Neneng Windayani)

44	Chemistry	ABS-422
Using Android-Based Learning Game on The Concept of Buffer Solution Sri Hermawati (a), Cucu Zenab Subarkah (a), Imelda Helsy (a*) Department of Chemical Education, UIN Sunan Gunung Djati Bandung, Jalan A. H. Nasution No. 105 Cibiru Bandung 0614 Indonesia *e-mail: imeldahelsy[at]uinsgd.ac.id Abstract In the digital era it is now necessary to develop android-based learning media. Important buffer concept developed through android games because it includes abstract concepts, memorization and calculations. An Android-based game learning media has been developed on the buffer solution concept that contains questions about evaluating buffer material. The research method used is the stages of developing the ADDIE model (analysis, design, development, implementation, and evaluation). This research only reaches the development stage which produces an Android-based learning game product. The results of the validation carried out on 3 expert lecturers, namely material experts, media experts, and learning experts showed that the Android-based buffer solution learning game is valid with a calculated value of 0.78. The results of a limited trial analysis of 10 students as respondents showed a percentage of 94.2%. Based on the results of the validation and trial, the Android-based learning game was declared feasible to be used as a learning medium on the concept of buffer solution. Keywords: android-based game, buffer solution PermaLink | Plain Format | Corresponding Author (Sri Hermawati)

45	Chemistry	ABS-947
Product Testing of Recycled Dried Coconut Leaf Ash and Olive Oil for Forehead Makeup of Solo Putri Style Bride Neneng Siti Silfi Ambarwati1*, Jenny Sista Siregar1, Islamudin Ahmad2 1Department of Cosmetology, Faculty of Engineering, Universitas Negeri Jakarta, Jl. Rawamangun Muka, East Jakarta, 13220, Indonesia 2Department of Phytochemistry, Faculty of Pharmacy, Universitas Mulawarman, Samarinda, Kalimantan Timur, Indonesia Abstract Background. Pidih is a cosmetic used on Javanese bride’s foreheads called paes. Peel material that is commonly used is wax which is colored as desired and has easy sticking properties. Objective. The objective of this research is to provide an alternative use of natural ingredients for pidih that used on the brides forehead makeup. Methods. Experiment was conducted to obtain black powder made from recycled dried coconut leaves and olive oil with the appropriate composition, and then applied as paes in the Solo putri style bride. Results. The use of cosmetics with natural ingredients, the leaves of dried coconut and olive oil, produce black, shiny, easily painted on the forehead, and rather oily. The cosmetic material can be used as an alternative for pidih that is made of wax. Conclusion. Alternative boiling from the ash of dried coconut leaves can be used as a substitute for conventional pidih. Keywords: pidih, dried coconut leaf, olive oil, forehead makeup, bride PermaLink | Plain Format | Corresponding Author (Neneng Siti Silfi Ambarwati)

46	Chemistry	ABS-202
SENECRASSIDIOL, SESQUTERPENOID COMPOUND FROM THE STEMBARK OF Aglaia simplicifolia (Meliaceae) Nunung Kurniasih(a*), Asep Supriadin(a), Hersa Milawati(b), Rizky Abdulah(c), Desi Harneti(b), Unang Supratman(b,d), Mohamad Nurul Azmi B Mohamad(e) (a)Department of Chemistry, Faculty of Sciences and Technology, Sunan Gunung Djati Islamic State University, Bandung 40614, Indonesia (b)Department of Chemistry, Faculty of Mathematics and Natural Sciences,Universitas Padjadjaran, Jatinangor 45363, Indonesia (c)Department of Pharmacology and Clinical Pharmacy, Faculty of Pharmacy,Universitas Padjadjaran, Jatinangor 45363, Indonesia (d)Central Laboratory of Universitas Padjadjaran, Jatinangor 45363, Indonesia (e)School of Chemical Sciences, Universiti Sains Malaysia,11800 Minden, Penang, Malaysia * Corresponding author: nunungkurniasih[at]uinsgd.ac.id Abstract Previous phytochemical studies from the Aglaia genus reported the presence of terpenoid compound. This research describe the isolation and structure elucidation of sesquiterpend compound from the stembark of Aglaia simplicifolia. Dried stembark of A. simplicifolia extracted with methanol and then partitioned with n-hexane, ethyl acetate, and n-butanol, respectively. The n-hexane extract then was separated and purified with chromatography techniques to obtain isolated compound. The chemical structure of isolated compound were elucidated by IR, NMR 1D, NMR 2D as well as mass spectra and by comparison with those previously reported spectra data. The compound identified as senecrassidiol. Keywords: Aglaia simplicifolia, stembark, senecrassidiol. PermaLink | Plain Format | Corresponding Author (Nunung Kurniasih)

47	Chemistry	ABS-203
STEROID COMPOUNDS FROM THE STEMBARK OF Aglaia simplicifolia (Meliaceae) AND CYTOTOXIC EFFECTS AGAINST HELA CERVICAL CANCER CELL LINES Nunung Kurniasih(a*), Asep Supriadin(a), Hersa Milawati(b), Rizky Abdulah(c), Desi Harneti(b), Unang Supratman(b,d), Mohamad Nurul Azmi B Mohamad Taib(e) (a)Department of Chemistry, Faculty of Sciences and Technology, Sunan Gunung Djati Islamic State University, Bandung 40614, Indonesia (b)Department of Chemistry, Faculty of Mathematics and Natural Sciences, Universitas Padjadjaran, Jatinangor 45363, Indonesia (c)Department of Pharmacology and Clinical Pharmacy, Faculty of Pharmacy, Universitas Padjadjaran, Jatinangor 45363, Indonesia (d)Central Laboratory of Universitas Padjadjaran, Jatinangor 45363, Indonesia (e)School of Chemical Sciences, Universiti Sains Malaysia,11800 Minden, Penang, Malaysia * Corresponding author: nunungkurniasih[at]uinsgd.ac.id Abstract Two steroid compounds, ergosterol peroxide (1) and stigmasterol (2) have been isolated from the stembark of Aglaia simplicifolia belong to Meliaceae family. The chemical structures of 1 and 2 were identified on the basis of spectroscopic evidence including UV, IR, NMR 1D, NMR 2D as well as mass spectra and by comparison with those previously reported spectra data. The cytotoxic effects against HeLa cervical cancer cell lines of the extracts and compounds were studied. Keywords: Aglaia simplicifolia, steroid, HeLa cervical cancer cell lines. PermaLink | Plain Format | Corresponding Author (Nunung Kurniasih)

48	Chemistry	ABS-459
Development of Chemistry Students 21st Century Skills through Science, Technology, Engineering, Art, and Mathematics (STEAM) Project of Electrolyte Non-Electrolyte Solutions Yuli Rahmawati, Mega Ayu Agustin, Achmad Ridwan, Erdawati, Darsef Darwis (a),R Rafiuddin (b) a. Universitas Negeri Jakarta Jl Rawamangun Muka, Jakarta Timur *yrahmawati[at]unj.ac.id b. Universitas Halu Oleo Jalan Kampus Bumi Tridharma, Andunohu, Kambu, Kendari, Sulawesi Tenggara Abstract The paper portrays the integration of Science, Technology, Art, Engineering, and Mathematics (STEAM) project in chemistry learning of electrolyte non-electrolyte solutions for developing 21st-century skills. The participant of the thirty-two of year-10 students has engaged in the study. The research employed qualitative research with multiple data collection of semi-structured interviews, classroom observations, reflective journals, and documentation were guided by the 21st-century skills rubric. In addition to the project has been assessed with the criteria of project development, STEAM integration, and product quality. Students designed an innovation project with the integration of STEAM in developing the building miniature by using the nature electrolyte solution sources, such as lemon, lime, apples, and salt water. Students created posters and video projects and presented in the project exhibition. Students are able to integrate their knowledge from various fields to solve problems and create new innovations. The students have developed the 21st-century skills of collaboration, communication, critical thinking, creativity and innovation besides using the technology as a tool for learning. The engaging learning environment has encouraged students to develop their skills and chemistry conceptual understanding. Keywords: chemistry learning, STEAM, 21st-century skills, electrolyte non-electrolyte solutions PermaLink | Plain Format | Corresponding Author (Yuli Rahmawati)

49	Chemistry	ABS-206
Ethyl Acetate Fraction of Moringa oleifera Leaves Induces Cell Cycle Arrest on T47D Breast Cancer Cell via G0/G1 through Cyclin D1 Expression Riza Apriani (a,b*), Shabarni Gaffar (b), Tati Herlina (b) a) Chemistry, Faculty of Mathematics and Natural Science, Universitas Garut Jalan Jati No. 48B, Garut 44151, Indonesia *aprianiriza[at]uniga.ac.id b) Chemistry Department, Faculty of Mathematics and Natural Science, Universitas Padjadjaran Jalan Raya Bandung-Sumedang Km. 21, Jatinangor 45363, Indonesia Abstract Cancer is a frightful disease and represents one of the biggest health-care issues for the human race and demands a proactive strategy for cure. Exploration of natural product containing anticancer agent provide a promising line for research on cancer. Moringa plant (Moringa oleifera) is one of the medicinal plants used in traditional medicine for the treatment of cancer. Several studies have reported that water and alcoholic leaves extracts of M. oleifera have anticancer activity in some cancer cell line, including HepG2 liver cancer cells, A549 lung cancer cells, Caco-2 colon cancer cells and MDA-MB-231 breast cancer cells, but study on T47D breast cancer cells has not reported yet. Therefore, this study was carried out to investigate the cytotoxic activity of ethyl acetat fraction of M. oleifera (EMO) on T47D cells by observing cell cycle profile. Cytotoxic activity was determined by MTT assay. Cell cycle analysis was performed using flow cytometry and cyclin D1 expression was analyzed using immunocytochemistry method. Based on preliminary MTT assay, T47D treated with EMO demonstrated a medium cytotoxic effect with an IC50 value of 135.312 ug/mL. Further assay indicated that EMO induced cell cycle arrest on G0/G1 phases. Immunocytochemistry assay showed that the EMO decreased expression of cyclin D1. Keywords: Breast cancer, cell cycle, Moringa oleifera, T47D cell PermaLink | Plain Format | Corresponding Author (Riza Apriani)

50	Chemistry	ABS-463
Culturally Responsive Teaching Approach and Ethnochemistry Integration of Tegal Culture for Developing Chemistry Students Critical Thinking Skills in Acid-Base Learning Yuli Rahmawati, Himaniyatul Rizqol Baeti, Achmad Ridwan, Suhartono (a*),R Rafiuddin (b) a Universitas Negeri Jakarta Jl Rawamangun Muka, Jakarta Timur, Indonesia *yrahmawati[at]unj.ac.id b. Universitas Halu Oleo Jalan Kampus Bumi Tridharma, Andunohu, Kambu, Kendari, Sulawesi Tenggara Abstract This study aimed to develop critical thinking skills through Culturally Responsive Teaching (CRT) approach and ethnochemistry of Tegal culture. The teaching approach is focusing on exploring the culture and local wisdom in Tegal Culture especially in Acid-Base such as Jamasan Tradition, Nginang, and Moci from chemistry perspectives integrated into CRT. The study employed the teaching model which consists of five phases of self-identification, cultural understanding, collaboration, critical reflections, and transformative construction. The study involved 35 students of year 11 in secondary school in Balapulang Tegal. The qualitative methodology approach has been employed with observation, interviews, critical thinking test, and reflective journals as data collection. The results showed that the integration of ethnochemistry in CRT approach has engaged students in developing their critical thinking skills in developing a conclusion, making the connection, conceptual understanding, and interpretation with the critical thinking skills test shows 40% students have reached level 3 (Satisfactory). In addition to the students engaged in the cultural identity empowerment, meaningful chemistry learning experiences, and team working. The students have been challenged in developing their critical thinking skills. Keywords: chemistry learning, culturally responsive teaching, ethnochemistry, critical thinking skills, acid-base PermaLink | Plain Format | Corresponding Author (Yuli Rahmawati)

51	Chemistry	ABS-719
Antioxidant Potentials of Cream Containing Natural Virgin Olive Oil and Virgin Coconut Oil Asmiyenti Djaliasrin Djalil (*), Hanifa Setyawan, Muhammad Iqbal Gumelar, Nunuk Aries Nurulita, Arif Budiman Faculty of Pharmacy, Universitas Muhammadiyah Purwokerto Jl. Raya Dukuhwaluh, PO. Box 202 Purwokerto 53182, Indonesia *asmiyentidjaliasrindjalil[at]ump.ac.id Abstract Exposure the ultraviolet (UV) radiation results in a photo-oxidative reaction that reduces the antioxidant defense system and increases the formation of reactive oxygen species (ROS) on the skin. Antioxidant creams protect the skin from adverse effects of UV which cause the initial signs of aging. Several creams containing 0.02 (F1); 0.2 (F2); and 2% of virgin olive oil (VOO) or virgin coconut oil (VCO) were prepared. Antioxidant activities of VOO, VCO, and their creams were evaluated by DPPH radical scavenging assay. The results showed that the oils and formulations have antioxidant activities. The IC50 value of VOO, F1, F2, and F3 of VOO were 31.7±0.1; 176.3±5.9; 111.9±4.7; 90.4±5.5 µg/mL, respectively. Furthermore, The IC50 value of VCO, F1, F2, and F3 of VCO were 44.7±2.0; 62.56±1.8; 53.56±1.7; 47.14±1.7 µg/mL, respectively. The formulation of antioxidant cream containing VOO meets the requirement of stability and physical properties. Meanwhile, the formulation of antioxidant cream containing VCO meets the requirement of stability and some physical properties, except for pH value. Keywords: Antioxidant cream; Virgin olive oil; Virgin coconut oil PermaLink | Plain Format | Corresponding Author (Asmiyenti Djaliasrin Djalil)

52	Chemistry	ABS-465
THE ANALYSIS OF WATER QUALITY AND HOTEL LIQUID WASTE IN UBUD REGION, GIANYAR Anny Eka Pratiwi and Ni Luh Utari Sumadewi Faculty of Medical and Health Science, Warmadewa University, Denpasar, Bali (1) Faculty of Sains, Health, ant Technology, Dhyana Pura University, Badung, Bali Abstract A research on the analysis of water quality and hotel liquid waste in Ubud regency, Gianyar-Bali has been conducted. The analysis of raw water quality was done to discover whether the raw water can be appropriately classified as clean water. The parameters used in analyzing the raw water are its bacteriological and hardness level. Analysis on the quality of liquid waste was done discover whether the hotel liquid waste can still be categorized align with the government standard in the disposal to the surrounding environment. Based on the result of hotel raw water analysis, five samples have aligned with the clean water standard, which is possible to categorized as clean water; while for the analysis of hotel liquid waste, the parameters used are turbidity, pH, BOD, COD and bacteriological test. The analysis shows that four hotels have exceeded the reasonable level of waste, where scheduled surveillance is required in keeping the environment away from waste disposal. Keywords: raw water, hotel waste, pH, turbidity, hardness, BOD. COD, bacteriological. PermaLink | Plain Format | Corresponding Author (Anny Eka Pratiwi)

53	Chemistry	ABS-469
Students Engagement in Science Learning through the Integration of Ethnopedagogy in Wastewater Treatment Project Yuli Rahmawati, Achmad Ridwan, Alin Mardiah, Witri Sandryani (a*), Pramita Cucu Mawarni (b),Arief Setiawan (c) (a)Jl Rawamangun Muka, Jakarta Timur Universitas Negeri Jakarta *yrahmawati[at]unj.ac.id (b) SMA Bakti Mulya 400 Jl. Lingkar Selatan, Pondok Pinang, Jakarta Selatan 12310 (c)Arief Setiawan SMP Pembangunan Jl. Pengayoman III No. 95, Utan Kayu Utara Jakarta Timur Abstract The paper portrays the study of the integration of ethnopedology in wastewater treatment project to engage science students in learning environmental pollution. The study involved two classes in junior high school in Jakarta. The cultural practices in dealing with environmental pollution from five regions of Jakarta, Bandung, East Java, Central Java, and Banten have been integrated into the study. The qualitative research with multiple data collection of reflective journal, interviews, and science concept test. The project of wastewater treatment has been developed through the information of indigenous knowledge which has been explored. The results show that the ethnopedagogy integration in science learning has engaged students in understanding their cultural identity and developing their problem solving, critical and creative thinking skills. The science of conceptual understanding has been developed throughout the learning experiences. In addition to students have developed their skills in communication and collaboration with completing the project. The students faced the challenges of shifting their identity from passive to active learners within meaningful and enjoyable learning experiences. Keywords: ethnopedagogy, science learning, environment pollution, wastewater treatment project, students engagement PermaLink | Plain Format | Corresponding Author (Yuli Rahmawati)

54	Chemistry	ABS-476
Chemistry Students Cognitive Structure in Oxidation-Reduction through Learning Cycle 8E Yuli Rahmawati, Sylvia Faustine, Achmad Ridwan, Chaeriyatun Nissa Auliyani, Irma Ratna Kartika (a*), R Rafiuddin (b) (a) Universitas Negeri Jakarta Jl Rawamangun Muka, Jakarta Timur *yrahmawati[at]unj.ac.id (b) Universitas Halu Oleo Jalan Kampus Bumi Tridharma, Andunohu, Kambu, Kendari, Sulawesi Tenggara Abstract This study aimed to analyse the students’ cognitive structure on the concept of oxidation reduction by employing learning cycle 8E model. The participants of 32 students in year-10 were involved in the study. The data was collected by drawing writing technique presented through student worksheets, interview, observations, and reflective journal. The learning cycle 8E was applied which consist of engage, explore, e-search, elaborate, exchange, extend, evaluate and explain stages. Data analysis consists of data reduction, data presentation, and conclusion. Students’ cognitive structure was divided into three categories which are an understanding, misconception and no understanding. Categories of understanding were found in the concept of redox, oxidizing agents and acid-base nomenclature and transitions. Students’ misconception categories were found in redox applications and polyatomic. Students faced the challenges in understanding the oxidation number and binary nomenclature. The results showed that misconceptions were decreased through the implementation of the learning cycle 8E. Learning cycle 8E also has implications on students’ critical thinking, collaboration, and empathy communication skills. Keywords: learning cycle 8E model, drawing writing technique, reduction oxidation drawing writing technique, cognitive structure, misconceptions PermaLink | Plain Format | Corresponding Author (Yuli Rahmawati)

55	Chemistry	ABS-222
Phytochemical Analysis of Methanolic Extract of Cashew Rose (Syzigium Jambos (L.) Alston) Leaves and Its Antioxidant Activity Dhini Annisa Rahmasari Kanto (a); Mirnawati (b); Fajar Fauzi Abdullah (a); Farid Perdana (b); Iqbal Musthapa (a) a) Department of Chemistry, Faculty of Mathematics and Natural Sciences, Garut University Jalan Jati No. 42B, Garut 44151, Indonesia *dhini.annisakanto[at]gmail.com b) Department of Pharmacy, Faculty of Mathematics and Natural Sciences, Garut University Jalan Jati No. 42B, Garut 44151, Indonesia Abstract Syzygium is a genus belongs to Myrtaceae. One species of the genus is cashew rose (Syzygium jambos (L.) Alston) which contains secondary metabolites, such as flavonoids, tannins, steroids/terpenoids, alkaloids and saponins. This study aimed to find the content of these secondary metabolites using thin layer chromatography (TLC) and its antioxidant activity. The simplicia of cashew rose leaves was extracted by maceration using methanol as a solvent for 64 hours. This results in methanolic extract of cashew rose leaves. The resulted chromatogram using n-hexane and ethyl acetate eluent showed that the methanolic extract of leaves cashew rose has at least five compounds with retention value (Rf) consecutively were 0.32, 0.36, 0.68, 0.72, and 0.84. The stains could be seen in UV light 356 nm, but not in UV light 254 nm. It can be concluded that these compounds were classified as nonfenolic compound. The antioxidant test of methanolic extract of cashew rose leaves showed a very strong antioxidant activity with IC50 value of 13,554 ug/mL. Keywords: Syzygium jambos (L.) Alston; chromatogram; DPPH; antioxidant; IC50 PermaLink | Plain Format | Corresponding Author (Dhini Annisa Rahmasari Kanto)

56	Chemistry	ABS-226
ANTIOXIDANT ACTIVITY OF VOLATILE COMPOUND FROM Syzygium aromaticum (L.) Leaves Aika Latifah Alawiyah(a*), Astri Senania(a), Halimah Sari(b), Farid Perdana(b) dan Iqbal Musthafa(c) a). Program Studi Kimia, Fakultas MIPA, Universitas Garut Jl. Jati 42B, Tarogong Garut, Indonesia 55141 *aikalatifah[at]uniga.co.id b). Program Studi Farmasi, Fakultas MIPA, Universitas Garut Jl. Jati 42B, Tarogong Garut, Indonesia 55141 c). Program Studi Kimia, Fakultas MIPA, Universitas Pendidikan Indonesia Jl. Dr. Setiabudi No. 229, Bandung, Indonesia 40153 Abstract Secondary metabolites of Syzygium aromaticum (L.) leaves essensial oil have been identified as antioxidants. This study aimed to determine the volatile compounds of Syzygium aromaticum (L.) leaves essential oil and antioxidant activity. Fresh Syzygium aromaticum (L.) leaves were extracted by steam distillation. Identification of volatile compounds was done by Gas Chromatography Mass Spectroscopy (GC-MS). DPPH assay was used to evaluated an antioxidant activity of samples. Volatile compounds of Syzygium aromaticum (L.) leaves essential oil resulted 15 compounds. The resulted of DPPH assay showed very strong antioxidant. Keywords: Antioxidants, Clove, Essential oil, PermaLink | Plain Format | Corresponding Author (Aika Latifah Alawiyah)

57	Chemistry	ABS-741
Computational Study of Inclusion Complex between Omeprazole Enantiomer and β-Cyclodextrin : NBO and RDG Analysis Atthar Luqman Ivansyah1,*, Enung Siti Nurhidayah2, Citra Deliana Dewi Sundari3, Muhamad A. Martoprawiro4, Buchari2 1Master Program in Computational Science, Faculty of Mathematics and Natural Sciences, Institut Teknologi Bandung, Jl.Ganesha No. 10, Bandung, West Java, 40132, Indonesia 2Division of Analytical Chemistry, Department of Chemistry, Faculty of Mathematics and Natural Sciences, Institut Teknologi Bandung, Jl. Ganesha No. 10, Bandung, West Java, 40132, Indonesia 3Department of Chemistry Education, UIN Sunan Gunung Djati Bandung, Jl. Cimincrang, Cimenerang, Panyileukan, Bandung, West Java, 40292, Indonesia 4Division of Physical and Inorganic Chemistry, Department of Chemistry, Faculty of Mathematics and Natural Sciences, Institut Teknologi Bandung, Jl. Ganesha No. 10, Bandung, West Java, 40132, Indonesia *corresponding author: atthar[at]compscience.itb.ac.id Abstract NBO and RDG analysis of inclusion complex between R/S-omeprazole (OMZ) enantiomer and β-cyclodextrin (CYD) have been carried out to elucidate the interaction between them in order to understand the performance of β-cyclodextrin for the separation of omeprazole enantiomer. NBO analysis results showed that the inclusion complex of R-omeprazole with β-cyclodextrin is more stable than the inclusion complex of S-omeprazole with β-cyclodextrin, in which the total value of the stabilization energy (E(2)) caused by hydrogen bonding in the inclusion complex of R-omeprazole with β-cyclodextrin is 150.22 kcal/mol and in the inclusion complex of S-omeprazole with β-cyclodextrin is 115.62 kcal/mol. From RDG analysis results, beside hydrogen bonding, there are also Van der Waals interaction and steric effect on the interaction between omeprazole enantiomer and β-cyclodextrin. Keywords: NBO, RDG, inclusion complex, enantiomer, omeprazole, β-cyclodextrin. PermaLink | Plain Format | Corresponding Author (Enung Siti Nurhidayah)

58	Chemistry	ABS-486
Problem-Based Learning Devices Oriented of Green Chemistry in Reaction Rate Concept Nurul Fauziah (a*), Yayuk Andayani (b), Aliefman Hakim (b) a) Postgraduated student of Science Education, University of Mataram. Jalan Majapahit No. 62, Lombok, Indonesia *imnurulfz[at]gmail.com b) Science Education, Postgraduated Program, University of Mataram. Jalan Majapahit No. 62, Lombok, Indonesia Abstract Chemistry learning should be able to facilitate students to have 21st century competencies and skills and also conservative attitude towards the environment. However, in its implementation was encountered obstacles, one of which is the problem of representative learning devices. The aims of study to produce and discover the quality of problem-based learning devices oriented to green chemistry in the reaction rate concept. Learning device consists of syllabus, lesson plan, student worksheet, modules, and test instruments. This research and development adapted Nieveens model which consisted of four stages: preliminary research, prototyping stage, summative evaluation, and reflection and documentation. The quality of the learning devices developed was measured through analysis of validity and practicality. Product validity assessment used validation questionnaires distributed to experts, the data obtained were analyzed by using the content validity formula. Practicality used response questionnaires assessed by teachers and students, and implementation of learning was analyzed by using a percentage of practicality. This study resulted in the average of content validity being 0,67 categorized valid. The practicality percentage of each espect is 90,87%, 80,06%, and 80,56% catogorized highly practical. The concluded that learning devices developed fulfills the criteria for developing quality products that are valid and practical. Keywords: Learning devices, problem-based, green chemistry, reaction rate concept. PermaLink | Plain Format | Corresponding Author (NURUL FAUZIAH)

59	Chemistry	ABS-489
Variations of Binding, Washing, and Concentration of Imidazole on Purification of Recombinant Fim-C Protein Salmonella typhi with Ni-NTA Resin Muktiningsih Nurjayadi (1), Rafi Afrizal (1), Dudi Hardianto (2), Kurnia Agustini (2), 1 Department of Chemistry, Mathematics and Science Faculty, Universitas Negeri Jakarta 2Laboratory of Agro and Biomedical Industry Technology Development, Badan Pengkajian dan Penerapan Teknologi (BPPT) Abstract Typhoid fever is an endemic disease in Indonesia. Prevention of typhoid fever can be done by administering vaccines. It is known that one of the raw materials for vaccines is a recombinant protein. This study aims to obtain information on the optimum conditions for purification of Salmonella typhi Fim-C recombinant protein with Ni-NTA resin as vaccine raw material. The three main stages of the purification process in this study were binding, washing, and elution of S. typhi Fim-C recombinant proteins. The binding and washing variations of recombinant proteins were carried out twice, four times and six times, while the elution process was carried out at imidazole concentrations of 200 mM, 250 mM, and 300 mM. Purification with a binding process four and six times gave almost the same intensity of S. typhi Fim-C protein bands. Whereas protein was elution at an imidazole concentration of 300 mM showed higher band instability. The results of characterization using SDS-PAGE and analysis using software ImageJ gel analysis showed that the longer the incubation time and the repetition of the binding process, the more protein bound to the resin. Furthermore, the more washing processes are obtained the purer proteins. Based on the data obtained it can be concluded that the purification of the S. typhi Fim-C recombinant protein was optimum at a four-time binding process, six times washing and a 300 mM imidazole concentration. These results are expected to be the basis for recombinant protein refining on a pilot scale and industry scale in better vaccine preparation. Keywords: Salmonella typhi, Protein purification, Recombinant Protein, Ni-NTA Resin PermaLink | Plain Format | Corresponding Author (Muktiningsih Nurjayadi)

60	Chemistry	ABS-1013
Preparation and Photocatalytic Activity of Hematite from Iron Sand Modified ZnO for Indigo Carmine Degradation Surya Lubis*, Ilham Maulana, Sheilatina, Linda Mahyuni Department of Chemistry, Faculty of Mathematics and Natural Sciences, Universitas Syiah Kuala Abstract Modification of hematite (α-Fe2O3) with ZnO to produce ZnO/α-Fe2O3 composites by sol gel method and their photocatalytic activity testing on the degradation of indigo carmine (IC) dye has been done. The hematite was extracted from iron sand taken from Syiah Kuala Beach, Deah Raya, Aceh Province by using hydrochloride acid and co-presipitated by using ammonium hydroxide. The ZnO/α-Fe2O3 composites were prepared with the mol ratio of ZnO to α-Fe2O3 1:5, 5:1 and 1:1. The characterization by using X-Ray Difractions (XRD) and Scanning Electron Microscopy Energy Dispersive X-Ray Spectroscopy (SEM-EDS) was conducted in order to study the physical and chemical properties of the materials. The result of photocatalytic activity test showed that composites with the mol ratio of ZnO to α-Fe2O3 1:5 has the highest photocatalytic activity with the percent of degradation (% D) of IC are 91,67% and 93,18% under UV light and sunlight irradiation, respectively. These highest of photocatalytic activity was obtained at the initial pH of dye solution =1, photocatalyst dosage of 300 mg, initial dye concentration was 15 ppm and irradiation time 120 minutes under UV light and 90 minutes under sunlight. Keywords: hematite; ZnO; indigo carmine: photocatalyst; sol gel PermaLink | Plain Format | Corresponding Author (Surya Lubis)

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