Development of Interactive E-Workbook Based on Peer-Led Team Learning on Collaboration Skills and Critical Thinking in Basic Chemistry Concept

Many students struggle to understand chemistry because it is abstract, conceptual, and involves numerous mathematical operations. Collaboration skills are needed for students to develop collaborative and critical thinking as part of 21st century life skills. This study aims to develop an interactive e-workbook based on PLTL (Peer-Led Team Learning) that meets the criteria of being valid, practical, and effective against collaboration and critical thinking skills. This research is an ADDIE-based development research with analysis, design, development, implementation, and evaluation stages. Limited trials were conducted on students in basic chemistry classes. The validation results show that e-workbook is valid, practical, and effective. The results of limited trial showed that collaboration skills improved in the good category with average score is 75%, and critical thinking skills improved in the medium category with average score is 0.33. It shows that the interactive e-workbook based on the PLTL model can improve collaboration and critical thinking skills and can be used to solve problems in group discussions with the help of an expert leader

Development of Interactive E-Workbook Based on Peer-Led Team Learning on Collaboration Skills and Critical Thinking in Basic Chemistry Concept

Many students struggle to understand chemistry because it is abstract, conceptual, and involves numerous mathematical operations. Collaboration skills are needed for students to develop collaborative and critical thinking as part of 21st century life skills. This study aims to develop an interactive e-workbook based on PLTL (Peer-Led Team Learning) that meets the criteria of being valid, practical, and effective against collaboration and critical thinking skills. This research is an ADDIE-based development research with analysis, design, development, implementation, and evaluation stages. Limited trials were conducted on students in basic chemistry classes. The validation results show that e-workbook is valid, practical, and effective. The results of limited trial showed that collaboration skills improved in the good category with average score is 75%, and critical thinking skills improved in the medium category with average score is 0.33. It shows that the interactive e-workbook based on the PLTL model can improve collaboration and critical thinking skills and can be used to solve problems in group discussions with the help of an expert leader

Optimasi Kinerja Kombinasi Adsorben dalam Mereduksi Logam Besi dan Nikel Sampel Air

Clean water or drinking water is one of the supporting materials for the survival of living things, especially humans, which should be free from heavy metal contamination and pose no risk to health. In an effort to reduce heavy metal levels in improving water quality through simple techniques and based on natural ingredients, the authors use jackfruit skin and natural zeolite as adsorbents. The purpose of this study was to determine the adsorption capacity of activated carbon from jackfruit skin combined with natural zeolite in reducing the concentration of iron (Fe) and nickel (Ni). The research was conducted on a laboratory scale using the method of varying the concentration of activated carbon which was analyzed using Atomic Absorption Spectrophotometry (AAS). The optimum adsorption power in reducing the concentration of Fe metal occurs in the x:y composition with the adsorbed concentration (mass of analyte) of 0.4083 ppm (0.1021 mg) for 60 minutes. Meanwhile, Ni metal was found in a combination of 2x:y composition dyes with the adsorbed concentration (mass of analyte) of 0.6017 ppm (0.1504 mg). The adsorption capacity of the adsorbent generally decreased with increasing mass of the dye packaged activated carbon adsorbent both in the analysis of Fe and Ni metal content.Air bersih atau air minum merupakan salah satu bahan penunjang keberlangsungan makhluk hidup terutama manusia dimana seharusnya bebas dari kontaminasi logam berat dan tidak memberikan resiko terhadap kesehatan. Sebagai upaya untuk mengurangi kadar logam berat dalam memperbaiki kualitas air melalui teknik sederhana dan berbasis bahan alam, maka penulis manfaatkan kulit nangka dan zeolit alam sebagai adsorben. Tujuan dari penelitian ini yaitu untuk mengetahui kemampuan daya adsorpsi karbon aktif kulit nangka yang dikombinasikan dengan zeolit alam dalam mereduksi konsentrasi logam besi (Fe) dan nikel (Ni). Penelitian dilakukan dalam skala laboratorium dengan menggunakan metode variasi konsentrasi karbon aktif yang dianalisi menggunakan Spektrofotometri Serapan Atom (SSA). Daya adsorpsi optimum dalam mereduksi konsentrasi logam Fe terjadi pada komposisi x:y dengan konsentrasi (massa analit) yang teradsorpsi yaitu 0,4083 ppm (0,1021 mg) selama 60 menit. Sedangkan logam Ni terdapat pada kombinasi kemasan celup komposisi 2x:y dengan konsentrasi (massa analit) yang teradsorpsi yaitu 0,6017 ppm (0,1504 mg). Kemampuan daya adsorpsi adsorben secara umum menurun dengan bertambahnya massa adsorben karbon aktif kemasan celup baik pada analisis kadar logam Fe maupun Ni

Turunan Senyawa Flavonoid dari Daun Macaranga involucrata (Roxb.) Baill dari Buton Tengah, Sulawesi Tenggara

Macaranga merupakan salah satu genus terbesar dari famili Euphorbiaceae yang terdiri dari 300 spesies dengan nama lokal mahang-mahangan. Tumbuhan Macaranga tersebar luas di wilayah Afrika dan Madagaskar di bagian barat hingga ke wilayah tropis Asia, Australia utara dan kepulauan Pasifik. Di Indonesia tumbuhan Macaranga tersebar di beberapa daerah yaitu daerah Papua, Maluku, Sulawesi, Kalimantan, Sumatera, Bangka, dan Jawa. Kajian fitokimia beberapa spesies Macaranga menunjukan adanya kelompok senyawa fenolik yaitu turunan flavonoid dan stilben, serta turunan terpenoid. Senyawa turunan fenolik tersebut memiliki keunikan dari struktur molekulnya, yaitu adanya subtituen tambahan dari metabolit terpenoid yaitu prenil (C5), geranil (C10), farnesil (C15), dan geranilgeranil (C20). Pada penelitian ini telah dilakukan isolasi metabolit sekunder dari daun M. involucrata (Roxb.) Baill dengan metode maserasi menggunakan pelarut aseton, kemudian dilanjutkan pemisahan dan pemurnian dengan menggunakan kromatografi cair vakum dan kromatografi radial untuk mendapatkan senyawa murni. Penentuan struktur dilakukan berdasarkan analisis data spektrum NMR 1D (1H-NMR dan13C-NMR), NMR 2D (NOESY, TOCSY, HSQC, dan HMBC), dan spektrum massa (MS). Berdasarkan metodologi tersebut, dua senyawa turunan flavon yaitu 5,7,4’-trihidroksi-3’(3-metilbut-2-enil)-3-metoksiflavon (1) dan makarangin (2), telah berhasil diisolasi dari tumbuhan ini. Berdasarkan hasil penelitian tersebut menunjukan daun M. involucrata (Roxb.) Baill yang berasal dari Kabupaten Buton Tengah, Sulawesi Tenggara menghasilkan senyawa fenolik turunan flavonoid. Kata kunci: Euphorbiaceae, Macaranga involucrata (Roxb.) Baill, flavon. Macaranga is one of the largest genera of the family Euphorbiaceae comprising 300 species with local name “mahang-mahangan”. Macaranga is widespread in the region of Africa and the west of Madagascar to the tropical regions of Asia, northern Australia, and the Pacific islands. In Indonesia Macaranga spread in several areas:  Papua, Maluku, Sulawesi, Kalimantan, Sumatra, Bangka, and Java. Phytochemical studies showed the presence of several phenolic compounds such as flavonoids and stilbene derivatives. The phenolic compounds have a unique molecular structure with the addition of some substituents such as prenyl (C5), geranyl (C10), farnesyl (C15), and geranylgeranyl (C20). This research has been conducted on the isolation of secondary metabolites from the leaves of M. involucrata (Roxb.) Baill by maceration method using acetone, followed by separation and purification by using liquid vacuum chromatography and radial chromatography to obtain pure compounds. Determination of the structure is based on data analysis of 1D NMR spectrum (1H-NMR and 13C-NMR), 2D NMR (1H-1HCOSY, NOESY, TOCSY, HSQC, and HMBC), and mass spectra (MS). Based on this methodology, two flavone derivatives 5,7,4'-trihydroxy-3'(3-methylbut-2-enyl)-3-methoxy flavone (1) and macarangin (2), have been isolated from this plant. Based on these results showed that leaf of M. involucrata (Roxb.) Baill from Central Buton, Southeast Sulawesi produces phenolic compounds from flavonoid derivatives. Keywords: Euphorbiaceae, Macaranga involucrata (Roxb.) Baill, flavone

Identifikasi Struktur Komponen Senyawa Kimia Kulit Batang Ketapang (Terminalia catappa L.)

Ketapang (Terminalia catappa L.) is a type of flowering plant that has been widely used by the community, especially in traditional medicine. This research aims to identify the chemical compound components of Ketapang bark using Virgin Coconut Oil (VCO) solvent. Research methods include making VCO, maceration extraction, solubility testing, identification of chemical compound components using FTIR and GC-MS. The mass of VCO is 744.32 grams (14.88% soaking). The mass of Ketapang bark extract weighed 183.88 grams (0.63% soaking). The solubility test shows that VCO and extracts are generally nonpolar. Identification results using FT-IR show that VCO has C-H, C=O and C-O groups, while ketapang bark extract has aliphatic –CH, C=O, C-O, C-OH, C-N and aromatic C-H groups. Identification using GC-MS showed that VCO had 112 peaks, among the 112 peaks that had a similarity index of 80% there were 14 peaks, while the ketapang bark extract had 190 peaks and 11 peaks had a similarity index. Thus, it can be concluded that the components of the VCO compound are decanoic acid, dodecanoic acid, tridecanoic acid, myristic acid, pentadecanoic acid, 2-monocaprin (2TMS derivative), palmitelaidic acid, palmitic acid, and stearic acid. Meanwhile, Ketapang stem bark extract contains heptadecanoic acid, (z) oleic acid, elaidic acid, 1-ethoxy-4'-methoxy-2,2'-binaptyl-1,4-dione, eikosan, 7-methyl-z-tetradeken- 1-ol-acetate, beta-alanine, sarcosine, 1-aminomethyl-cyclododecanol, and dodecanoic acid, 2,3-dihydroxypropyl ester.Ketapang (Terminalia catappa L.) merupakan jenis tumbuhan berbunga yang telah digunakan masyarakat secara luas khususnya dalam pengobatan tradisional. Penelitian ini bertujuan untuk mengidentifikasi komponen senyawa kimia kulit batang ketapang menggunakan pelarut Virgin Coconut Oil (VCO). Metode penelitian meliputi pembuatan VCO, ekstraksi maserasi, uji kelarutan, identifikasi komponen senyawa kimia menggunakan FTIR dan GC-MS. Massa VCO sebanyak 744,32 gram (rendamen 14,88%). Massa ekstrak kulit batang ketapang seberat 183,88 gram (rendamen 0,63%). Uji kelarutan menunjukkan VCO dan ekstrak secara umum bersifat nonpolar. Hasil identifikasi menggunakan FT-IR menunjukkan VCO memiliki gugus C-H, C=O dan C-O, sedangkan ekstrak kulit batang ketapang memiliki gugus –CH alifatik, C=O, C-O, C-OH, C-N, dan C-H aromatik. Identifikasi menggunakan GC-MS menunjukkan VCO memiliki 112 puncak, diantara 112 puncak yang memiliki indeks similaritas mencapai 80% sebanyak 14 puncak, sedangkan ekstrak kulit batang ketapang terdapat 190 puncak dan yang memiliki indeks similaritas sebanyak 11 puncak. Dengan demikian, dapat disimpulkan komponen senyawa VCO yaitu asam dekanoat, asam dodekanoat, asam tridekanoat, asam miristat, asam pentadekanoat, 2-monocaprin (2TMS derivative), asam palmitelaidat, asam palmitat, dan asam stearat. Sedangkan ektsrak kulit batang ketapang mengandung asam heptadekanoat, asam (z) oleat, asam elaidat, 1-etoksi-4’-metoksi-2,2’-binaptyl-1,4-dion, eikosan, 7-metil-z-tetradeken-1-ol-asetat, beta-alanin, sarkosin, 1-aminometil-siklododekanol, dan asam dodekanoat, 2,3-dihidroksipropil ester

PENINGKATAN RESPON IMUN IKAN NILA (Oreochromis niloticus) DENGAN PEMBERIAN EKSTRAK DAUN Macaranga tanarius

The problem of tilapia farming farmers is the presence of disease, which is caused by viruses, bacteria, fungi, and parasites. Prevention by farmers is the provision of vaccines, antibiotics, and immunostimulants. However, it is only effective in one type of disease. Therefore, alternative prevention is needed with natural ingredients from Macaranga tanarius leaf extract which has tannins, terpenoids, flavonoids, prenylflavonoids, and lignans that have immunostimulator properties. M. tanarius leaf extract was injected by intramuscular injection of tilapia. This research method used a completely randomized design (CRD) with five treatments with three repetitions. Treatment (P1) using physiological solution (positive control), P2 = 4 % (v/v) (1mL extract + 24 mL distilled water), P3 = 8 % (v/v) (2mL extract + 23 mL distilled water), P4 = 12% (v/v) (3mL extract + 22 mL distilled water) and P5 without injection of M. tanarius leaf extract (negative control). The results showed that the leaf extract of M. tanarius could respond to phagocytic activity (45.82%) and increase the number of white blood cells (12.43 x 108 cells/mL). Based on this study, the extract of M. tanarius showed an increase in the immune response of tilapia

ANALISIS KADAR MINERAL DALAM ABU BUAH NIPA (NYPA FRUCTICANS) KALIWANGGU TELUK KENDARI SULAWESI TENGGARA

Research about Levels of ash analysis in Nipa Fruit (Nypa fructicans) Kaliwanggu Kendari Gulf South East Sulawesi have been done.  Research carried out by gravimetric method and AAS. The ash content of old nipa fruit at a temperature 450°C dan 550°C obtained amounted to 1.01% and 0.89%. while the young nipa fruits obtained ash content of 0.88% and 0.86% at450°C dan 550°C. Mineral content of old nipa fruit which had become ash at a temperature of 450°C obtained at 1.3769 ppm, 7.9167 ppm, 3.7876 ppm, 9.2365 ppm, respectively for Fe, Mg, K, and Na. On the other hand, at a temperature of 550°C obtained at 1.1153 ppm, 8.0127 ppm, 3.7990 ppm and 9.3634 ppm, respectively for Fe, Mg, K, and Na. On young fruit nipah obtained concentration of 0.8769 ppm, 7.9939 ppm, 3.8260 ppm, 9.4041 ppm, respectively for Fe, Mg, K, and Na at ash temperature 450°C. Meanwhile, at a  ash temperature of 550°C obtained concentration of 0.9230 ppm, 7.9738 ppm, 3.7468 ppm and 9.3861 ppm, respectively for Fe, Mg, K, and Na. The water content obtained from the old and young nipa flesh fruit obtained at 41.86% and 33.49%, respectively. Key words: Level of mineral analysis, Nypa fructicans, Gravimetric, AAS ABSTRAK Telah dilakukan penelitian dengan judul “Analisis Kadar dalam Abu Buah Nipa (Nypa fructicans)” Kaliwanggu Teluk Kendari Sulawesi Tenggara. Penelitian dilakukan dengan metode gravimetri dan AAS. Kadar abu buah nipa tua pada suhu 450°C dan 550°C diperoleh sebesar 1,01% dan 0,89%, sedangkan pada buah nipa muda diperoleh kadar abu sebesar 0,88% dan 0,86% berurut-turut untuk suhu 450°C dan 550°C. Kadar mineral buah nipa tua yang diabukan pada suhu 450°C diperoleh sebesar 1,3769 ppm, 7,9167 ppm, 3,7876 ppm, 9,2365 ppm, berturut-turut untuk Fe, Mg, K, dan Na. Sedangkan pada suhu 550°C diperoleh sebesar 1,1153 ppm, 8,0127 ppm, 3,7990 ppm, dan 9,3634 ppm, berturut-turut untuk Fe, Mg, K, dan Na. Pada buah nipa muda diperoleh kadar sebesar 0,8769 ppm, 7,9939 ppm, 3,8260 ppm, 9,4041 ppm, berturut-turut untuk Fe, Mg, K, dan Na pada suhu pengabuan 450°C. Sedangkan pada suhu pengabuan 550°C diperoleh kadar sebesar 0,9230 ppm, 7,9738 ppm, 3,7468 ppm, dan 9,3861 ppm, berturut-turut untuk Fe, Mg, K, dan Na. Adapun kadar air yang diperoleh dari daging buah nipa tua dan muda diperoleh sebesar 41,86% dan 33,49%.  Kata kunci: Analisis kadar mineral, Nypa fructicans, Gravimetri, AA