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ANALISIS SENYAWA ALKALOID DAUN TANAMAN JOHAR (Cassia siamea Lmk.) YANG BERPOTENSI SEBAGAI INSEKTISIDA PADA NYAMUK Setiawan, Topan; Aminah, Sitti; Jura, Minarni R.
Jurnal Akademika Kimia Vol 2, No 3 (2013)
Publisher : Universitas Tadulako

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Abstract

Research about alkaloid compound of johar plant leaf (Cassia siamea Lmk.) which potential as insecticide at mosquito. The methods are used is laboratory experiment from johar plant leaf extract. Alkaloid has product from separated extract of johar plant leaf. Maximum wave has product by UV-Vis spectrophotometer is 306 nm. TLC product of johar plant leaf extracts are 2 components (Rf 0.89 and 0.91). TLC product of johar plant leaf alkaloid is 1 component (Rf 0.91). The product of HPLC showed 4 components for johar plant leaf and 2 components for alkaloid. The insecticide force of 25 mosquitos did by third for extract and alkaloid. The products are johar leaf extract have insecticide force for each treatment are 14, 10 and 14 mosquitos although alkaloids are 13, 8 and 2 mosquitos.
PENGARUH LAMA PENYIMPANAN DAN KONSENTRASI NATRIUM BENZOAT TERHADAP KADAR VITAMIN C CABAI MERAH (Capsicum annuum L) (The Effect Of Length Storage And Sodium Benzoat Concentration On The Vitamin C Levels Of Red Chili (Capsicum annuum L) Oktoviana, Yanti; Aminah, Sitti; Sakung, Jamaluddin
Jurnal Akademika Kimia Vol 1, No 4 (2012)
Publisher : Universitas Tadulako

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Red chillies (Capsicum annuum L) are considerable horticultural crops widely grown in Indonesia, which has a high value and demand in market. Besides it contains higher vitamin C (ascorbic acid) and beta-carotene than other fruits such as papaya, mango, pineapple and watermelon, red chillies has a very low storability as it is susceptible to decay and the over-production of chili resulting in postharvest decay. To prevent the decay, red chillies are preserved using preservatives. Preservative used in this study is sodium benzoate since it is claimed as an effective against fungi. This study aimed to determine the effect of the concentration of sodium benzoate against storage time of red chillies (Capsicum annuum L) and also to determine the effect of the concentration of sodium benzoate levels towards vitamin C in preserved red chili. The method used in this experiment was a laboratory experiment using a visible spectrophotometry. The results showed that the use of sodium benzoate as a preservative can extend the storability of red chillies and sodium benzoate concentration also affect levels of vitamin C contained in red chillies. The level obtains at the highest concentration of 1.5% which is 54 mg/100 g with 8 days of storability.
PENGARUH SUBSTITUSI TEPUNG AMPAS KELAPA DAN WORTEL (Daucus Carota L) TERHADAP NILAI ORGANOLEPTIK DAN NILAI GIZI COOKIES Aminah, Sitti; tamrin, tamrin; Baco, Abdu Rahman
Jurnal Sains dan Teknologi Pangan Vol 3, No 5 (2018): JURNAL SAINS DAN TEKNOLOGI PANGAN
Publisher : JURUSAN ILMU DAN TEKNOLOGI PANGAN, UNIVERSITAS HALU OLEO

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (332.579 KB) | DOI: 10.33772/jstp.v3i5.5223

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ABSTRACT The purpose of this study was to determine the effect of coconut pulp and carrot flour formulations on the organoleptic properties and proximate values of cookies. This study used a Completely Randomized Design (CRD) with coconut pulp flour formulation, carrot flour and wheat flour ie. M0 (100% of flour wheat flour), M1 (40% ofcoconut pulp flour: 20% of carrot flour: 40% of wheat flour), M2 (35% of coconut pulp flour: 25% of carrot flour: 40% of wheat flour), M3 (30% of coconut pulp flour: 30% of carrot flour: 40% of wheat flour) and M4 (25% of coconut pulp flour: 35% of carrot flour: 40% of wheat flour). The results showed that the selected product based on organoleptic was the M3 formula. The nutritional value of the M3 cookies product consisting of water, protein, fat, carbohydrate and fiber contents were 3.50%, 5.52 %, 9,147%, 19,72%, 71,170% and 21,40%. Coconut pulp and carrot flour cookies had nutritional value according to standards and based on organoleptic assessment can be accepted (preferred) by panelists. Keywords: Cookies, coconut pulp flour, carrot flour. ABSTRAK Tujuan penelitian ini adalah untuk mengetahui pengaruh formulasi tepung ampas kelapa dan tepung wortel terhadap sifat organoleptik dan nilai proksimat cookies. Penelitian ini menggunakan Rancangan Acak Lengkap (RAL) dengan formulasi tepung ampas kelapa, tepung wortel dan tepung terigu yaitu M0 (100% tepung terigu), M1 (tepung ampas kelapa 40% : tepung wortel 20% : tepung terigu 40%), M2 (tepung ampas kelapa 35% : tepung wortel 25% : tepung terigu 40%), M3 (tepung ampas kelapa 30% : tepung wortel 30% : tepung terigu 40%) dan M4 (tepung ampas kelapa 25% : tepung wortel 35% : tepung terigu 40. Hasil penelitian menunjukkan bahwa produk terpilih berdasarkan organoleptik adalah formula M3. Nilai gizi dari produk cookies M3 yang terdiri dari kadar air kadar abu protein kadar lemak kadar karbohidrat dan kadar serat berturut-turut sebesar 3,50%, 5,52%, 9,147%, 19,72%, 71,170% dan 21,40%. Cookies tepung ampas kelapa dan wortel memiliki nilai gizi sesuai standar dan berdasarkan penilaian organoleptik dapat diterima (disukai) oleh panelis. Kata kunci: Cookies, tepung ampas kelapa, tepung wortel. PENDAHULUAN
Longitudinal Study of Metacognitive Skills and External Representation of Students in the Context of Problem-Solving Ijirana Ijirana; Jusman Mansyur; Muh. Rizal; Sitti Aminah
Indonesian Journal on Learning and Advanced Education (IJOLAE) Vol. 3, No. 3, September 2021
Publisher : Faculty of Teacher Training and Education, Universitas Muhammadiyah Surakarta, Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.23917/ijolae.v3i3.13563

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This study aims to longitudinally describe the metacognitive skills and external representation in the context of problem-solving at Chemistry Education, Tadulako University. The qualitative study respondents were selected from a number of first year students for two consecutive semesters. Two respondents were selected based on results of selection using a metacognitive skills assessment questionnaire (MCAI) and we categorized as high and medium.  Three problems were resolved by respondents at intervals of one to two weeks in each semester through a one-on-one thinking aloud and it was followed by a semi-structured interview. Data collection was recorded using a video camera. Metacognitive skills and external representation data from the odd and even semesters were deeply analyzed. This analysis technique was carried out by examining the results of problem solving and semi-structured interviews in detail and matching them with the indicators of metacogni-tive skills and external representation used by both respondents. The data analysis results showed that the thinking ability of respondents with high metacognitive skills in problem solving, experienced developments over time along with the development of their cognitive regulation and external representation. On the other hand, respondents with intermediate metacognitive skills during problem solving, were relatively the same for two consecutive semesters. Therefore, teachers need to consider the use of learning strategies by taking into account the number of students who have dominant characteristics in classroom learning, in terms of metacog-nitive skills and external representation.
ARANG AKTIF SERBUK GERGAJI KAYU JATI (TECTONA GRANDIS L.F) SEBAGAI BAHAN ADSORBEN PADA PEMURNIAN MINYAK JELANTAH Nusratullah Nusratullah; Sitti Aminah
Media Eksakta Vol 16 No 1 (2020)
Publisher : Universitas Tadulako

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (538.024 KB) | DOI: 10.22487/me.v16i1.732

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sed cooking oil can increase the potential for cancer in the body. Therefore, used cooking oil processing efforts were made to improve its quality by using activated charcoal adsorbent of Tectona Grandis L. F sawdust. This study aimed to improve the quality of used cooking oil through refinign by using charcoal adsorbent of Tectona Grandis L.f sawdust. used cooking oil samples were obtained from Ogoamas 1 Village, Sojol Utara District, Donggala Regency. Based on the results of testing the quality of the oil obtained, the water content was 0.22%, free fatty acid content was 0.25% peroxide number was 1.83 meq / Kg, the iodic number was 45, specific gravity was 0.900 g / mL and oil color clear oil with absorbance value was 0.031 A. Based on the quality of several parameters of cooking oil using activated  charcoal of Tectona Grandis L.f sawdust, it has fulfilled the  quality requirements of cooking oil according to SNI 3741-1995.
PEMANFAATAN SERBUK GERGAJI KAYU JATI (TECTONA GRANDIS L.F) SEBAGAI ADSORBEN LOGAM CU (II) Gusti Ayu Arini; Sitti Aminah
Media Eksakta Vol 16 No 2 (2020)
Publisher : Universitas Tadulako

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (420.055 KB) | DOI: 10.22487/me.v16i2.739

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Sawdust is one of the industrial wastes that can be used as an absorbent. The chemical content in sawdust is the same as in its wood, i.e lignin, cellulose, and hemicellulose. This study aimed to determine the optimum contact time, optimum weight, and adsorption capacity of Cu (II) ions by teak sawdust using the atomic absorption spectrophotometry (AAS). Determination of optimum contact time was carried out with time variations of 10, 30 and 60 minutes, the optimum weight with various weight of 0.5, 1, and 1.5 grams, and the adsorption capacity of teak sawdust in various concentrations of 50, 100, 150 and 200 ppm. The results showed that the equilibrium contact time was reached at 30 minutes, and the percentage of adsorption of Cu (II) was 91.25%. The optimum weight for metal adsorption was 1.5 gram, and the adsorption percentage of adsorbed Cu (II) ions was 96.18%. The adsorption capacity was determined from the adsorption isotherm according to the Langmuir and the freundlich models. The adsorption isotherm model of Cu (II) of teak sawdust follows the Langmuir isotherm model with a maximum adsorption capacity (qmax) of 2.058 mg/g.
PEMANFAATAN SERBUK GERGAJI SEBAGAI BAHAN BAKU BRIKET Pratiwi Nova Sari; Sitti Aminah
Media Eksakta Vol 16 No 2 (2020)
Publisher : Universitas Tadulako

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (206.52 KB) | DOI: 10.22487/me.v16i2.740

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Wood sawdust is one of the wastes from wood processing industry such as sawdust and peel residues. They are cheap raw materials and potential as a source of alternative energy by processing it into charcoal briquettes. The use of charcoal briquettes as a substitute for fossil energy sources has several advantages including the relatively less smoke emitted because it has been released during the carbonization process. They can be stored for a long time and the calor value is higher than wood. Charcoal briquettes are made from wood sawdust which is added by tapioca flour as glue. This study was conducted in two main stages, processing charcoal briquette and characterization. The characterization of charcoal briquettes are including density, moisture, ash, volatile substances levels, carbon bound, long flame and calor value. The results obtained from the charcoal briquettes are a density of 0.384 gr/cm3, a moisture of 2.44%, an ash of 4.82%, a volatile substance of 19.13%, a carbon bond of 74.44%, a briquette flame of 6.75 minutes/gr and the calor value of 5127 cal/gr. This study concluded that wood sawdust briquette has the potential to be used potentially as substitued for fuel.
Penentuan Kadar Total Flavonoid Kunyit Putih (Curcuma zedoria Rosc.) dengan Variasi Jenis Pelarut Evayana Evayana; Sitti Aminah
Media Eksakta Vol 18 No 1 (2022)
Publisher : Universitas Tadulako

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (333.213 KB) | DOI: 10.22487/me.v18i1.995

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Determination of Total Levels of White Turmeric Flavonoids (Curcuma zedoria Rosc.) with Variation of Solvent Types. White turmeric (Curcuma zedoria Rosc.) is a herbal plant that has many health benefits in healing several diseases. It can grow wild in the open with moist soil. The purpose of this study was to determine the total levels of white turmeric flavonoids with various types of solvents. The solvents used in were water and ethanol. The quantitative test of flavonoids in the White Turmeric extract used a quercetin standard solution curve. The samples were analyzed by UV-Vis spectrophotometry at a maximum wavelength of 435 nm. The average yield obtained in the water extract was 0,073% and 0,102% in the ethanol extract.   Keywords: Flavonoids, White Turmeric, UV-Vis Spectrophotometry
Penentuan Kadar Besi dan Kesadahan pada Sumber Air di Kelurahan Besusu Tengah Kecamatan Palu Timur Abdurrahman Mujahida; Sitti Aminah
Media Eksakta Vol 18 No 1 (2022)
Publisher : Universitas Tadulako

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (273.207 KB) | DOI: 10.22487/me.v18i1.1026

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This study aims to determine whether the analyzed clean water meets the quality standard requirements set by PERMENKES RI No. 492 of 2010. The parameters measured in this study were pH, odor, temperature, color (in-situ testing) as well as iron and hardness which were tested ex-situ using Atomic Absorption Spectrophotometry and Complexometric Titration. The results of this study are the springs on the S. Parman road for the parameters of pH, color, hardness, and iron, respectively 8.26 pH; colorless; 120 mg/L; and 0.129 mg/L, where the results met the requirements but for the odor (fishy) and temperature (36oC) parameters did not meet the quality standards. Meanwhile, the water sources in the Besusu Tengah Village, which existed before the earthquake in Palu City, had met the requirements set by the government
Utilization of Kalpataru Flower Extract (Hura crepitans Linn) as an Alternative Acid Base Indicator Bayu Riswanto; Sitti Aminah
Jurnal Akademika Kimia Vol. 9 No. 3 (2020)
Publisher : Universitas Tadulako

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (414.329 KB) | DOI: 10.22487/j24775185.2020.v9.i3.pp148-157

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Kalpataru flower (Hura crepitans Linn) is an anthocyanin-containing plant. This study aims to utilize extract from the kalpataru flower as an alternative acid base indicator and determine the type of acid-base titration suitable for extracting the kalpataru flower indicator. Kalpataru flowers are macerated with methanol solvent for around 2 hours. Kalpataru flower extract was tested as an indicator in acid-base solution, buffer, and compared with phenolphthalein and methyl orange for acid-base titration, namely: strong acids with strong bases, weak acids with strong bases, and weak bases with strong acids. The results obtained in this study were: indicator extract of brownish yellow kalpataru flowers, in strong red acids, in strong bases of dark green, in weak pink acids, and in weak bases in light green. In the buffer, the indicator extract of the kalpataru flower has a range of pH pH 4-5 (pink-colorless) and pH 9-11 (yellowish green-dark green). The indicator of kalpataru flower extract can be used on strong acid titration with strong bases, weak acids with strong bases and weak bases with strong acids. Kalpataru flower extract can be used as an acid-base indicator.