Abstrak. Telah dilakukan penelitian uji aktivitas antioksidan daun gulma siam (Chromoleana odorata L.) dengan metode 1,1-difenil-2-pikrilhidrazil (DPPH). Tujuan penelitian ini untuk mengetahui kandungan senyawa metabolit sekunder, golongan flavonoid dan aktivitas antioksidan yang terdapat dalam daun gulma siam. Sebanyak 315 g daun gulma siam kering yang sudah dihaluskan, dimaserasi dengan etanol 95% diperoleh 100 g ekstrak kental etanol. Sebanyak 70 g ekstrak kental etanol difraksinasi dengan pelarut metanol dan n-heksana menghasilkan fraksi kental metanol 30,72 g dan n-heksana 14,62 g. Hasil skrining fitokimia ekstrak etanol menunjukkan positif mengandung senyawa alkaloid, flavonoid, saponin, tanin dan steroid. Fraksi metanol positif mengandung senyawa alkaloid, flavonoid, saponin, dan tanin. Fraksi metanol dilakukan isolasi dengan metode kromatografi kolom menggunakan eluen n-heksana : etil asetat : diklorometana (1:1:1) sebagai fase gerak pertama, kemudian ditingkatkan gradien kepolarannya untuk menghasilkan pemisahan secara sempurna. Hasil isolasi diperoleh 8 fraksi ( Abstract. The antioxidant activity of siam weed leaf (Chromoleana odorata L.) has been done with 1,1-diphenyl-2-picrilhidrazil (DPPH) method. This study is intended to know the the content of secondary metabolite compounds, the group of flavonoid and antioxidant activity that found in siam weed leaf. The 315 g dry siam weed leaf that was refined, macerated with ethanol 96% produced 100 g of ethanol viscous extract. The 70 of ethanol viscous extract was fractionated with methanol and n-hexane solvent produced 30,72 g of methanol viscous fraction and 14,62 g nhexane. The results of phytochemical screening of ethanol extract showed positive that contained compound of alkaloids, flavonoids, saponins, tannins and steroids. Methanol fraction showed positive that contained compound of alkaloids, flavonoids, saponins and tannins. The isolation in methanol fraction was made by coloumn chomatography method using eluent n-hexene : acetate ethyl : dichloromethane (1:1:1) as first mation phase. Then the polarity gradient was increased to produce complete separation. The result of isolation produced 8 fractions (A, B, C, D, E, F, G, H) and the analysis results with TLC showed fraction of A and B was positive contain flavonoids compound. Flaconoids compound that was contained in fraction A was estimated isoflvone group and fraction B was estimated group os isoflavone, flavone, flavonol and chalcone. Analysis FTIR showed that the fraction of A and B containing function group N-H, O-H (carboxylic acid), C=O (aldehyde and ester), C=C, C-H, C-X (flouride), C-O and C-N. The result of antioxidant activity test used DPPH method, obtained inhibitor concentration (IC50) for 15,5067 ppm of ethanol extract, 9,5671 of methanol fraction, 82,7808 ppm of fraction A and 16,2336 ppm of fraction B, while for comparison (ascorbic acid) is 0,8913 ppm. This, it can be concluded that strongert antioxidant activity was found in methanol fraction.

Abstrak. Tape merupakan hasil dari proses fermentasi bahan makanan dengan bantuan suatu mikroorganisme yang disebut ragi atau khamir. Pada umumnya, tape hasil fermentasi mengandung senyawa etanol. Namun, kadar etanol yang dihasilkan dipengaruhi oleh jenis bahan makanan dan ragi yang digunakan. Penelitian ini dilakukan untuk mengetahui pengaruh jenis singkong dan ragi terhadap kadar etanol tape singkong. Jenis penelitian ini adalah eksperimen yang menggunakan pendekatan kuantitatif. Data penelitian ini bersumber dari sampel tape singkong jenis Mentega dan Malang 2 yang dibuat menggunakan ragi Meulaboh dan Sigli. Teknik pengumpulan data yang digunakan adalah observasi terstruktur. Penelitian dilakukan dengan menitrasi larutan sampel yang sudah ditetesi indikator PP (1%) dengan larutan NaOH (0,1 M). Proses titrasi dilakukan pada sampel mulai hari ke-1 setelah peragian sampai hari ke-5. Data yang diperoleh selanjutnya dianalisis dengan analisis varian (ANOVA) menggunakan Rancangan Acak Lengkap (RAL). Berdasarkan hasil analisis data diperoleh beberapa temuan, yaitu: (1) jenis singkong berpengaruh tidak nyata terhadap kadar etanol tape; (2) jenis ragi berpengaruh tidak nyata terhadap kadar etanol tape; (3) interaksi antara jenis singkong dengan jenis ragi berpengaruh tidak nyata terhadap kadar etanol tape. Hasil analisis dengan ANOVA tidak menunjukkan adanya perbedaan yang signifikan, sehingga tidak dilakukan uji lanjut.Kata kunci: singkong, ragi, kadar etanol tape Abstract. Tapai is a product of fermentation of cassava with the aid of a microorganism called yeast or khamir. In general, tapai that produced from fermentation process contains an ethanol compounds. This study was conducted to determine the effect of varieties of yeast and cassava on ethanol level of tapai. This research use a quantitative approach. The sample of this research were Butter cassava and Malang 2 cassava which were fermented with using yeast from Meulaboh and Sigli. The data collected using structured observation technique. Research carried out by titrating NaOH (0.1 M) solution to the sample which have been added a PP indicators (1%). The titration on the samples started from  the first day  after fermentation untill fifth day (5th day). Data were analyzed by analysis of variance (ANOVA) using a completely randomized design (CRD). Based on the analysis of data obtained several findings, namely: (1) the type of cassava gave  no real effect on tapai's ethanol levels; (2) different types of yeast cast no real effect on tapai's ethanol levels ; (3) there are no real effect on ethanol level of tapai produced by the interaction between different yeast and cassava. The results of the ANOVA analysis showed no significant difference between treatments, so it is not carried out.Keywords: cassava, yeast, tapai's ethanol levels

<p>Research on the ethnochemistry study of using plants as traditional medicine in the Samadua District community has been conducted. In general, there are two ways to use plants as medicine: internal medicine (oral) and external medicine (topical). This type of research is descriptive qualitative with an ethnographic approach that aims to determine the types, benefits, processing methods, and chemical content of plants used as internal medicine by the people of Samadua District. Data collection techniques in this study were observation, interviews, and documentation. The sampling technique was carried out by purposive sampling, namely by conducting interviews with herbal practitioners, community leaders, and users. The results showed that in Samadua District, 54 plants were used by the community to treat diabetes, high blood pressure, cough, gout, cholesterol, diarrhea, and other complaints. Medicinal plants are processed by boiling, grinding, kneading, eating, making juice, or brewing. The most processing method is boiling at 46.34%, while the least is brewing at 1.21%. Plants can be used as drugs because they contain certain chemicals produced from secondary metabolites. The chemical constituents of these medicinal plants include flavonoids, alkaloids, saponins, tannins, terpenoids, phenolic compounds, glycosides, vitamins, steroids, and essential oils. Ethnochemistry studies combine public opinion with science regarding the effectiveness of plants considered useful as drugs based on the chemical compounds contained in these plants.</p>