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All Journal Natural Science: Journal of Science and Technology Dharmakarya : Jurnal Aplikasi Ipteks Untuk Masyarakat KOVALEN: Jurnal Riset Kimia Indonesian Journal of Chemistry AR-RAZI Jurnal Ilmiah ULIN: Jurnal Hutan Tropis Jurnal Riset Sains dan Kimia Terapan al Kimiya : Jurnal Ilmu Kimia dan Terapan

Ahmad Ridhay

Department Of Chemistry, Tadulako University, Jl. Sukarno-Hatta Km 9, Palu 94148, Central Sulawesi, Indonesia

Author-ID : 360572

Agriculture, Biological Sciences & Forestry Arts Humanities Biochemistry, Genetics & Molecular Biology Chemical Engineering, Chemistry & Bioengineering Chemistry Computer Science & IT Economics, Econometrics & Finance Engineering Environmental Science Languange, Linguistic, Communication & Media Public Health

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ANALISIS KADAR SERAT DAN KADAR PROTEIN SERTA PENGARUH WAKTU SIMPAN TERHADAP SEREAL BERBASIS TEPUNG AMPAS KELAPA DAN TEPUNG TEMPE Fitrianingsih Mozin; Nurhaeni; Ahmad Ridhay
KOVALEN: Jurnal Riset Kimia Vol. 5 No. 3 (2019): Edisi Desember
Publisher : Chemistry Department, Mathematics and Natural Science Faculty, Tadulako University

Research on dissolved protein and crude fiber flour based on coconut pulp and tempe flour has been performed. This study aims to determine the effect of shelf time on levels of dissolved protein and crude fiber flour-based cereal coconut pulp and tempeh flour. Cereals were made from coconut pulp flour and tempe flour as the main ingredients and the ratio of the ingredients was varied to 25:75; 50:50; and 75:25. The ratio of 25:75 produced the highest dissolved protein level of 3.88% and the 75:25 ratio produced the highest crude fiber of 21.96%. Keywords: Coconut pulp flour, tempe flour, dissolved protein, crude fiber

EKSTRAKSI DAN KARAKTERISASI KARAGENAN KASAR RUMPUT LAUT Eucheuma cottoni Asri jaya; Ni Ketut Sumarni; Ahmad Ridhay
KOVALEN: Jurnal Riset Kimia Vol. 5 No. 2 (2019): Edisi Agustus
Publisher : Chemistry Department, Mathematics and Natural Science Faculty, Tadulako University

Research on extraction and characterization of crude carrageenan from seaweed (eucheuma cottoni) has been carried out. The research aims to determine the optimum extraction time and temperature of crude carrageenan extract from seaweed (eucheuma cottoni). Crude Carrageenan was extracted from seaweed (eucheuma cottoni) by dissolving crushed seaweed in 8% KOH with variation of extraction times are 1 hour, 1.5 hours, 2 hours, 2.5 hours and 3 hours, and temperatures are 50, 70, 90, 110 and 130oC. The results were analyzed using a Completely Randomized Design (CRD). The results show that the optimum extraction time in producing the best quality of crude carrageenan is 2 hours at 50oC with percentage is 78.4%, viscosity is 9.155 cP, sulphate content is 3.102% and gel strength is 7 g. Keywords : eucheuma cottoni seaweed, crude carrageenan, characterization

POTENSI ANTIOKSIDAN METABOLIT SEKUNDER FRAKSI ETIL ASETAT DARI KULIT BATANG EBONI (Diospyros celebica Bakh.) Vivi Sasmita; Ahmad Ridhay; Hardi Ys
KOVALEN: Jurnal Riset Kimia Vol. 5 No. 2 (2019): Edisi Agustus
Publisher : Chemistry Department, Mathematics and Natural Science Faculty, Tadulako University

Research on the antioxidant potential of the secondary metabolite compound, ethyl acetate from ebony bark (Diospyros celebica Bakh.) has been conducted. This study aims to characterize and determine the antioxidant activity of secondary metabolites of ethyl acetate fraction from ebony bark. Ethyl acetate extract was fractionated using Liquid Vacum Chromatography (KVC) and Gravity Column Chromatography (KKG). The isolated compounds were characterized using UV-Vis and IR spectrophotometers. Data on maximum absorption of λmax 273 nm from UV-Vis analysis showed the presence of chromophore phenol. IR spectral data showed several specific peaks, among others, at wave number (ʋ) of 3425.58 cm-1 indicating the presence of –OH group, C-H aliphatic bond at ʋ of 2924.09 cm-1 and 2854.65 cm-1, and the peak at ʋ of 1604.77 -1465.90 cm-1 and 3078.39 cm-1 indicated the aromatic group, reinforcing the assumption that the isolates produced were phenolic compounds. IC50 value of 75.47 µg/mL from antioxidant activity testing showed that the isolates obtained were antioxidant compounds with strong antioxidant categories. Keywords: antioxidant, Diospyros, ebony, phenolic, isolation

PEMBUATAN Carboxymethyl cellulose (CMC) DARI PELEPAH NANAS (Ananas cosmosus Merr.) Ripdayana Ripdayana; Ahmad Ridhay; Erwin Abdul Rahim
KOVALEN: Jurnal Riset Kimia Vol. 5 No. 2 (2019): Edisi Agustus
Publisher : Chemistry Department, Mathematics and Natural Science Faculty, Tadulako University

A research about production of Carboxymethyl cellulose (CMC) from pineapple midrib (Ananas cosmosus Merr.) has been conducted. This research aims to determine the best cellulose ratio with sodium monochloro acetate and the best reaction time to the substitution degree of carboxymethyl cellulose from pineapple midrib fibers. This study used a Completely Randomized Design method with two independent variables, i.e. variations in the weight of sodium monochloroacetate (2.5 grams, 3 grams, 3.5 grams, 4 grams, and 4.5 grams) and variations in reaction time (1 hour, 2 hours, 3 hours, 4 hours , and 5 hours), each treatment was done duplo using 20 treatment units. The result of the study showed that the best ratio of sodium monochloroacetate to cellulose which produced carboxymethyl cellulose from pineapple midribs was 2.5: 2.5 with substitution degree value of 1.93 and optimum reaction time which produced carboxymethyl cellulose from pineapple midribs was 1 hour with substitution degree of 2.38. Keywords: Carboxymethyl cellulose, Pineapple midrib

KARAKTERISASI PIGMEN HASIL EKSTRAKSI AIR-ETANOL DARI BUAH SENGGANI (Melastoma malabathricum) Debi Christa Ondagau; Ahmad Ridhay; Nurakhirawati Nurakhirawati
KOVALEN: Jurnal Riset Kimia Vol. 4 No. 3 (2018): Edisi Desember
Publisher : Chemistry Department, Mathematics and Natural Science Faculty, Tadulako University

Telah dilakukan penelitian tentang Karakterisasi Pigmen Hasil Ekstraksi Air-Etanol Dari Buah Senggani (Melastoma malabathricum). Penelitian ini diawali dengan melakukan ekstraksi buah senggani secara maserasi menggunakan enam perbandingan kombinasi volume pelarut air:etanol yaitu 0:100; 5:95; 10:90; 15:85; 20:80 dan 25:75. Rendemen terbaik dari ekstraksi buah senggani didapatkan dari perbandingan pelarut 0:100 yaitu 4,7 %. Kemudian Ekstrak dianalisis dengan spektrofotometer UV-Vis, FTIR dan uji golongan senyawa. Spektrum UV-Vis ekstrak buah senggani dihasilkan pada panjang gelombang 540 nm dan interpretasi FTIR menunjukkan bahwa ekstrak mengandung gugus fungsi seperti O-H alkohol, C-O-C eter, C=C aromatik, C-H aromatik. Hasil uji golongan menunjukkan ekstrak mengandung senyawa flavonoid jenis antosianin.Kata kunci : Buah senggani, ekstraksi, antosianin

STUDI PERBANDINGAN RENDEMEN PRODUKSI XANTOFIL DAN KAROTEN KAPANG ONCOM MERAH PADA BERBAGAI WAKTU INKUBASI Asniawati Asniawati; Ahmad Ridhay; Prismawiryanti Prismawiryanti
KOVALEN: Jurnal Riset Kimia Vol. 4 No. 3 (2018): Edisi Desember
Publisher : Chemistry Department, Mathematics and Natural Science Faculty, Tadulako University

Telah dilakukan penelitian tentang studi perbandingan rendemen produksi xantofil dengan karoten kapang oncom merah pada berbagai waktu inkubasi. Penelitian ini bertujuan untuk mengetahui jumlah rendemen fraksi kelompok xantofil dan karoten dari berbagai waktu inkubasi kapang oncom merah pada medium tongkol jagung. Pengujian dilakukan dengan mengukur absorbansi ekstrak xantofil dan karoten pada instrumen spektrofotometer uv vis, parameter yang diamati adalah waktu inkubasi spora kapang oncom merah. Waktu inkubasi yang digunakan adalah dimulai dari hari ke 2, 3, 4, 5, 6, dan ke 7. Hasil penelitian menujukkan bahwa waktu inkubasi yang menghasilkan jumlah rendemen xantofil efektif pada hari ke 3 dengan rerata rendemen sebesar 4,435%. Sedangkan jumlah rendemen karoten efektif pada hari ke 5 dengan rerata rendemen 4,532%.Kata kunci: Xantofil, karoten, kapang oncom merah, waktu inkubasi, rendemen

Ekstraksi Glukomanan dari Umbi Gembili (Dioscorea esculenta L.): Extraction of Glucomannan from Gembili Bulbs (Dioscorea esculenta L.) Pratiwi Listyana Sareu; Nurhaeni; Ahmad Ridhay; Moh. Mirzan; Syamsuddin
KOVALEN: Jurnal Riset Kimia Vol. 7 No. 1 (2021): Edisi April
Publisher : Chemistry Department, Mathematics and Natural Science Faculty, Tadulako University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22487/kovalen.2021.v7.i1.12008

Gembili bulbs (Dioscorea esculenta L.) have a fairly high carbohydrate content, so they can potentially be a new source of glucomannan compounds. This study aims to determine the yield and glucomannan characteristics of Gembili bulbs at different extraction times and temperatures. Glucomannan was obtained by extraction with water at temperatures of 45, 60, 75, 90, and 105oC for 45, 60, 75, 90, and 105 minutes, and precipitated with isopropyl alcohol. The results showed that the highest yield was obtained at the extraction time of 90 minutes and a temperature of 105oC of 53.09%. The glucomannan of Gembili bulb has a molecular weight of 1,865 x 104 g/mol with ash and water content values of 0.866% and 10.45%, respectively. The results of identification of functional groups with an FTIR spectrophotometer showed that there was a functional group stretching vibration of glucomannan compounds, including the –OH group at a wavenumber of 3431 cm-1 and -C-O-C (glycosidic bond) at a wavenumber of 1020.34 cm-1 and bending vibration of -CH functional groups on wavenumber of 850.61 cm-1.

Aktivitas Antibakteri Ekstrak Metanol dari Kulit Batang Kelor (Moringa oleifera Lam.) Terhadap Bakteri Staphylococcus aureus dan Escherichia coli: Antibacterial Activity of Methanol Extracts from The Stem Bark of Moringa oleifera Lam. Against Staphylococcus aureus and Escherichia coli Nurul Cholifah; Ahmad Ridhay; Pasjan Satrimafitrah; Ruslan; Hardi Ys
KOVALEN: Jurnal Riset Kimia Vol. 6 No. 1 (2020): Edisi April
Publisher : Chemistry Department, Mathematics and Natural Science Faculty, Tadulako University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22487/kovalen.2020.v6.i1.12854

Antibacterial activity of Moringa oleifera Lam. stem bark has been tested against Staphylococcus aureus and Escherichia coli. The extraction of Moringa oleifera Lam. stem bark was used maceration method with methanol solvent and has obtained extract yield of 6.1%. The antibacterial activity test of Moringa oleifera stem bark extracts used a well diffusion method. The concentration of Moringa oleifera stem bark extract was varied to four concentrations of 1% 2% 3% 4% (w/v). The inhibition zone of methanol extract of Moringa oleifera stem bark against Staphylococcus aureus at extract concentrations of 1%, 2%, 3%, and 4% was 10.08 mm, 11.8 mm, 15.00 mm, and 17.02 mm, respectively. The methanol extract of Moringa oleifera stem bark at concentrations of 1%, 2%, 3%, and 4% could also inhibition of Escherichia coli growth with inhibition zone of 14.01 mm, 16.50 mm, 17.09 mm, and 17.10 mm, respectively. Keywords: Moringa Oleifera Lam., Antibacterial, Staphylococcus aureus, Escherichia coli

Aktivitas Antioksidan Akar Bawang Merah Lokal Palu (Allium cepa Var Aggergatum L.) dengan Berbagai Kepolaran Pelarut: Antioxidant Activity of Local Shallot Roots (Allium cepa Var Aggregatum L.) in Palu City with Various Solvent Nur Faidah; Nurhaeni; Ahmad Ridhay; Jusman; Abd. Rahman Razak; Syaiful Bahri
KOVALEN: Jurnal Riset Kimia Vol. 6 No. 3 (2020): Edisi Desember
Publisher : Chemistry Department, Mathematics and Natural Science Faculty, Tadulako University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22487/kovalen.2020.v6.i3.13662

Research on the antioxidant activity of the local onion roots of Palu (Allium cepa Var Aggregatum L.) with various polarity solvents has been carried out. This study aims to determine the potential of Palu local shallot root extract as an antioxidant and determine the IC50 value of the Palu local shallot root antioxidant activity. The method applied in this research is maceration using n-hexane, ethyl acetate, and ethanol. The extracts from each solvent were tested for their antioxidant activity by the DPPH method. The results of the study showed that the IC50 value in n-hexane extract, ethyl acetate extract, and ethanol extract were 579.98 ppm, 518.28 ppm 315.83 ppm and as a comparison used ascorbic acid obtained IC50 of 53.69 ppm. Based on the results obtained, the best antioxidant activity is in polar solvents (ethanol extract) compared to other solvents. Keywords: Antioxidants, roots, Palu local shallots, Allium cepa Var Aggregatum L.

Pembuatan Konsentrat Protein Ampas Kelapa (Cocos nucifera L.) Bebas Lemak pada Berbagai Konsentrasi NaOH: Production of Fat-Free Coconut Pulp (Cocos nucifera L.) Protein Concentrates at Various NaOH Concentrations Ulayya Kasio; Syaiful Bahri; Husain Sosidi; Khairuddin; Ni Ketut Sumarni; Ahmad Ridhay
KOVALEN: Jurnal Riset Kimia Vol. 7 No. 3 (2021): Edisi Desember
Publisher : Chemistry Department, Mathematics and Natural Science Faculty, Tadulako University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22487/kovalen.2021.v7.i3.14235

Coconut pulp contains up to 18.2% protein which is one of the wastes from coconut oil processing. Protein from coconut pulp can be used in the manufacture of protein concentrates which are widely used in the food industry. The purpose of this research is to determine the concentration of NaOH that can produce the yield and protein content of coconut pulp protein concentrate. Coconut pulp protein was extracted with NaOH at various concentrations of 0.5, 1, 1.5, 2, and 2.5 M, then continued with salting out using salt (NH4)2SO4 with a saturation of 65%. The crude protein content of coconut pulp protein concentrate was determined by the Kjeldahl method. The results showed that the use of 0.5 M NaOH resulted in the highest protein content of coconut pulp protein concentrate, which was 71.30% with a yield of 14.42%.

Co-Authors Abd. Rahman Razak Abd. Rahman Razak Abd. Rahman Razak Abustiana, Rahma Lolita Agriyani Marcelinda, Agriyani Aini Auliana Amar Aini Hoiriyah, Aini Alfian Noor Asniawati Asniawati Baehaqi Betzy Eppang Bryan Agung Rundubelo Darwin Darwin Debi Christa Ondagau Deddy Firman Didit Purwanto Djumidar Dwi Juli Puspitasari Dwi Juli Pusptasari Erwin Abdul Rahim Erwin Erwin Fatiah Riskah Fitrianingsih Mozin Gilang Almilda Hardi Ys Hardi Ys Husain Sosidi I Nyoman Adi Putra Ian van Altena Indriani Indriani Indriani Indriani Indriani Indriani Isabella de Nadra Ivitri Susana Jaya Hardi Jusman, Jusman Khairuddin Khairuddin - Khairuddin Khairuddin Kurniawati Kurniawati Lindawati, Eka Magfira Magfira Mappiratu Mappiratu Mappiratu Mappiratu Marsela, Anggi Mirzan, Muhamad Moh. Mirzan Moh. Mirzan Mohamad Afdal Musafira Musafira Musdalifah Musdalifah Naser, Inda Hastuti N Ni Ketut Sumarni Ni Luh Sumitriasih Nov Irmawati Inda Nunuk H. Soekamto Nur Faidah Nur Istiqomah Nur Madinah Rizal Nur'ain Nur'ain Nurakhirawati Nurakhirawati Nurakhirawati Nurhaen, Nurhaen Nurhaeni Nurhaeni Nurhaeni Nurhaeni Nurhaeni Nurhaeni Nurhaeni Nurhaeni Nurhaeni Nurhalisa, Sitti Nurmila Nurmila Nurul Bima Khasanah NURUL CHOLIFAH Oktavian Mangela Parwati Parwati Pasjan Satrimafitrah Patrisia Marcevin Rengku Pratiwi Listyana Sareu Prismawiryanti Prismawiryanti Rahma Wati Rahmadani, Indah Ashari Ripdayana Ripdayana Riski, Mutiara Zalfa Ruslan Ruslan Ruslan Sabarwati, Sitti Hadijah Siti Helmyati Sitti Nur Halizah SYAIFUL BAHRI Syaiful Bahri Syaiful Bahri Syamsuddin Syamsuddin Syamsuddin Tjodi Harlim Ulayya Kasio Vivi Sasmita Winarsii, Dessy

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