Optimization Experimental Procedure and Setup of a Guided Inquiry Laboratory Worksheet of Transesterification Reaction on Biodiesel Production

The aims of this research are producing an optimal experiment procedure and determining the feasibility of a guided inquiry laboratory worksheet of transesterification reaction on biodiesel production context. This research used research and development methods that composed of two stages, initial product preparation and model development (until limited testing). The data sources of this research are 20 students grade XII of science, seven chemistry teachers and three lecturers from chemistry education program of FPMIPA UPI. The instruments that used in this research are optimization and observation sheets of inquiry stages implementation, rubric of assessment students’ answer, sheets of assessment by teacher and lecturer, and student’s response questionnaires. The optimization of biodiesel production is: 12 mL of palm oil is added into erlenmeyer flask that contained boiling stone, then added by 0.12 g Potasium hidroxide in 4.5 mL methanol solution. The erlenmeyer flask then closed by rubber stopper with test tube in the middle of rubber stopper that filled with water and heated at 45oC in water bath for 5 mins by shaking the flask. The feasibility of laboratory experiment is categorized as very good. Teacher and lecturer assessment on the concept conformity, language, and the appearance of worksheet is categorized as very good. Student’s responses of laboratory activity and the worksheet are good

STUDY OF REACTION PATHWAY AND KINETIC OF ESTRAGOLE ISOMERIZATION TO CIS-ANETHOLE AND TRANS-ANETHOLE

Estragole isomerization in basic condition resulted cis- and trans-anethole. Hence, there were two reaction pathway of estragole isomerization i.e. parallel and consecutive. The reaction pathway gave information about reaction mechanism. Estragole isomerization was carried out in various kind and volume of solvent, base ratios, and at various time and temperature. The products were analyzed by GC-MS, and FTIR. The result showed that the estragole isomerization pathway in ethanol and ethylene glycol was parallel. The mechanism of estragole isomerization proceed through carbanion intermediate with Eatotal of 178,6238 J/mol .Keywords: estragole, cis-anethole, trans-anethole, isomerization pathway

Growth Process Of Organic Vetiver Root With Potato AS Intercropping Plant

Vetiver oil (Vetiveria zizanoides) is one of Indonesia main export commodities. Vetiver root is perennial plant and generally planted with vegetables as intercropping plant. Increasing the selling price of vetiver oil can be done by transferring the production of conventional vetiver oil (non-organic) to organic vetiver oil. Demonstration of land used was one hectare, which 2,000 m2 for planting vetiver root with potato (Solanum tuberosum) as inter-cropping plant and 8,000 m2 for vetiver root without intercropping, in Sukakarya-Samarang, Garut. The planting used goat and cow dung as manure, distillate water of vetiver oil and liquid bio-pesticide as pesticide. Variables studied included plant height, number of leaf and crotch. In the first quarter of the years, the number of leaf and crotch of vetiver root with intercropping was better than vetiver root without inter-cropping. However, there was not significant difference for plant height of vetiver root, both with and without intercropping. Products of organic potato as intercropping plant of vetiver root were less than those of non-organic potato, but the latter had a better texture and durability

Aktivitas Antioksidan Teh Rosela (Hibiscus Sabdariffa) Selama Penyimpanan Pada Suhu Ruang

Prosiding Seminar Nasional Sains dan Pendidikan Sains IX, Fakultas Sains dan Matematika UKSW Salatiga, 21 Juni 2014, Vol 5, No.1, p. 536-541Penelitian ini bertujuan untuk mengetahui aktivitas antioksidan teh rosela (Hibiscus sabdariffa) yang dibuat pada suhu 60°C dengan variabel lama penyeduhan selama penyimpanan teh pada suhu ruang (±25°C). Aktivitas antioksidan teh dianalisis terhada p radikal bebas DPPH (2,2-diphenyl-1-pycrilhidrazyl) menggunakan Spektrofometer UV-Vis dengan tiga variasi lama penyeduhan yaitu 20, 30 dan 40 menit dan diukur selama 3 hari berturut-turut mulai dari waktu pembuatannya. Aktivitas antioksidan teh rosela yang dibuat pada suhu 60°C dengan lama penyeduhan 20 menit pada hari ke-0, ke-1, dan ke-2 berturut-turut adalah 83,25%; 78,92%; dan 70,68%. Aktivitas antioksidan teh rosela yang dibuat pada suhu 60°C dengan lama penyeduhan 30 menit pada hari ke-0, ke-1, dan ke-2 berturut-turut adalah 61,70%; 59,36%; dan 49,55%. Aktivitas antioksidan teh rosela yang dibuat pada suhu 60 °C dengan lama penyeduhan 20 menit pada hari ke-0, ke-1, dan ke-2 berturut-turut adalah 51,12%; 43,13%; dan 31,48%. Hasil pengukuran menunjukan bahwa semua sampel teh rosela yang dibuat dengan lama penyeduhan baik 20 menit, 30 menit, maupun 40 menit, yang disimpan dalam suhu ruangan mengalami penurunan aktivitas antioksidan setiap harinya. Aktivitas antioksidan terbaik terjadi pada teh yang dibuat dengan lama penyeduhan 20 menit pada hari ke-0 yaitu 83,25%. Berdasarkan analisis statistik menggunakan metode ragam percobaan dua faktorial diketahui bahwa pengaruh lama penyeduhan dan lama penyimpanan teh rosela terhadap aktivitas antioksidannya signifikan pada taraf 5

Komposisi Kimia dan Uji Aktivitas Antibakteri Minyak Kemangi (Ocimum americanum L.) Terhadap Bakteri Escherichia coli, Shigella sonnei, dan Salmonella enteritidis

The chemical composition and antibacterial activity of basil oil (Ocimum americanum L.) against Escherichia coli, Shigellasonnei and Salmonella enteritidis have been determined. Basil oils were isolated from leaves and stems of basil (Ocimum americanumL.) with percolation method and analyzed by FTIR and GC-MS spectrometry. The antibacterial activity of basil oils were obtained byAgar diffusion method with various concentration (v/v) 2, 4, 6, 8, and 10% with ethanol p.a. as negative control, thiamfenicol, andtetracycline 500 mg as positive control. The produces essential oils from leaves and stems of basil by percolation are 1.06 and 0.22%,respectively. There are 22 components of basil oil were identifi ed, with a major component are citral (35.58%) and neral (29.56% ).Basil oil has not effectively against Escherichia coli and Shigella sonnei but effectively against Salmonella enteritidis at concentration 8 and 10%, with inhibition zone diameter are 10.25 and 10.93 mm respectively

Quality and Chemical Composition of Organic and Non-Organic Vetiver Oil

Vetiver oil (Vetiveria zizanoides) has been used as perfume materials, cosmetics, fragrance soaps, anti-inflammation, repellent, and insecticidal agents. Organic vetiver oil has higher economical value than non-organic vetiver oil and it has been regarded to be able to compete in the global market. Therefore, studies have been carried out using 1 hectare of land and the first generation of organic vetiver oil has produced 0.57% of yield, greater than non-organic (0.50%). The quality of organic and non-organic vetiver oil was analyzed by Indonesian Standard (SNI) parameter, pesticide residue test, chemical composition by GC/MS, and the appearance of vetiver root. In general, the result of organic and non-organic vetiver oil has fulfilled the national standard; the quality of organic vetiver oil was better than non-organic one. Physically, the appearance of organic vetiver root was better than non-organic vetiver root; organic vetiver root was denser, more appealing, and did not have any black spots. The pesticide residue of organic vetiver oil was lower than non-organic vetiver oil. Based on SNI test, vetiverol (oxygen compounds) in organic vetiver oil was higher than non-organic vetiver oil