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Tagor M. Siregar
Jurusan Teknologi Pangan, Universitas Pelita Harapan, Tangerang
Agriculture, Biological Sciences & Forestry Biochemistry, Genetics & Molecular Biology Chemical Engineering, Chemistry & Bioengineering Chemistry Computer Science & IT Control & Systems Engineering Economics, Econometrics & Finance Education Energy Engineering Environmental Science Industrial & Manufacturing Engineering Materials Science & Nanotechnology

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PEMANFAATAN UBI JALAR UNGU (Ipomoea batatas L. Poir) SEBAGAI PENGGANTI SEBAGIAN TEPUNG TERIGU DAN SUMBER ANTIOKSIDAN PADA ROTI TAWAR [Purple Sweet Potato (Ipomoea batatas L. Poir) as a Partial Subtitute of Wheat flour and Source of Antioxidant on Pla . Hardoko; Liana Hendarto; Tagor Marsillam Siregar
Jurnal Teknologi dan Industri Pangan Vol. 21 No. 1 (2010): Jurnal Teknologi dan Industri Pangan
Publisher : Departemen Ilmu dan Teknologi Pangan, IPB Indonesia bekerjasama dengan PATPI

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Abstract

       Purple sweet potato (Ipomoea batatas L. Poir) is potential for functional food, especially as antioxidant source due to its purple color and other nutrient content. The objective of this research was  to produce plain bread containing antioxidant by partial substitution of wheat flour with purple sweet potato flour. The result showed that the best plain bread was produced by a maximum substitution of 20% purple sweet potato flour to wheat flour. The hedonic characteristics of the resulting bread including aroma, taste, and texture were not significantly different from bread without substitution. Nevertheless, the crust was harder and darker. Addition of 1.0% GMS emulsifier and reduction of purple potato flour to 15% increased the score of softness, hedonic  texture, acceptance level, as well as the volume of the bread. The substituted bread had  antioxidant activity of 55833.78 ppm DPPH as shown by the IC50 value and contained  4.30% of dietary fiber.
PENGARUH PENAMBAHAN LAKASE DARI JAMUR TIRAM PUTIH (Pleurotus ostreatus) TERHADAP AKTIVITAS ANTIOKSIDAN TEH HIJAU [Effect of The Addition of Laccase from White Oyster Mushroom (Pleurotus ostreatus) Towards Antioxidant Activity of Green Tea] Tagor M. Siregar; A. Herry Cahyana; Natalia ,
Jurnal Teknologi dan Industri Pangan Vol. 23 No. 1 (2012): Jurnal Teknologi dan Industri Pangan
Publisher : Departemen Ilmu dan Teknologi Pangan, IPB Indonesia bekerjasama dengan PATPI

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Abstract

      Laccase is one of the enzymes that can be used in organic synthesis using aromatic compounds (polyphenols and aminofenol) as substrates. Polyphenol compound in green tea is flavan-3-ols or catechin which are susceptible to enzymatic reaction with laccase. In this research laccase isolated from white oyster mushroom was added into the green tea extract. Addition of laccase is expected to yield products with a higher antioxidant activity. Prior to it’s use, laccase activity was determined and had a specific activity of 0.54 Unit/mg. The green tea extract was prepared using methanol and water as solvents. The antioxidant activity was evaluated using 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical-scavenging activity method and the total flavonoid content was assayed by spectrophotometry. Antioxidant compounds are identified by using UV-Vis spectrophotometry and GC-MS. Addition of laccase into green tea extract resulted in precipitates showing a significant increase in flavonoid content and antioxidant activity. Use of methanol as solvent resulted in extract with higher antioxidant activity and total flavonoid than that extracted with water. Qualitative analysis with spectrophotometer UV-Vis and GC-MS showed that the new components in the precipitates were a variety of dimeric products with increased molecular weight and antioxidant activity. Addition of laccase into green tea extract has yielded products with higher antioxidant activity. 
Characteristics and Free Radical Scavenging Activity of Zinc Oxide (ZnO) Nanoparticles Derived from Extract of Coriander (Coriandrum sativum L.) Tagor Marsillam Siregar; Antonius Herry Cahyana; Regina Jessilia Gunawan
Reaktor Volume 17 No. 3 September 2017
Publisher : Dept. of Chemical Engineering, Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (273.072 KB) | DOI: 10.14710/reaktor.17.3.145-151

Abstract

Abstract Zinc Oxide (ZnO) nanoparticles were recently studied for its free radical scavenging activity.                     The formation of ZnO nanoparticles by means of biological method was known to be a simpler and more environmental friendly method. One of the biological methods used for the formation of ZnO nanoparticles was by utilizing the phytochemicals that were present in a plant extract.                                       The phytochemicals such as phenolic and flavonoid compound was able to reduce bulk metal Zinc into Zinc nanoparticles. Coriander (Coriandrum sativum L.) seeds and leaves were known to contain high amounts of phenolic compounds and flavonoid compounds. The aim of this study was to investigate the effect of different solvent polarities used to extract Coriander leaves and seeds towards the reducing power of plant extract and the free radical scavenging capacity of ZnO nanoparticles. The different solvents that were used to extract Coriander were deionized water, ethyl acetate, and hexane. The different solvent polarities affected the weight of the derived ZnO nanoparticles due to the different types of the extracted phenolic and flavonoid compounds. The different solvent polarities also affected the free radical scavenging capacity of ZnO nanoparticles. Ethyl acetate based extract of Coriander leaf resulted in the most weight of ZnO nanoparticles, 0.7907 g and the highest free radical scavenging capacity, 11.16%/mg ZnO nanoparticles. The free radical scavenging activity of ZnO nanoparticles decreased to 3.67%/mg ZnO nanoparticles after the process of calcination at 100°C and decreases to 0 %/mg ZnO nanoparticles after the process of calcination at 300 and 500°C. The diameter of ZnO particles increases from 128.1±33.5 nm to 552.3±61.1 nm after calcination. Kata kunci: calcination; free radical scavenging capacity; polarities; zinc oxide nanoparticles  Abstrak KARAKTERISTIK DAN AKTIVITAS PENANGKAL RADIKAL BEBAS NANOPARTIKEL SENG OKSIDA (ZnO) YANG DIBENTUK MENGGUNAKAN EKSTRAK KETUMBAR (Coriandrum sativum L.). Nanopartikel Seng Oksida (ZnO) saat ini tengah diteliti sehubungan dengan kapasitasnya dalam menangkal radikal bebas. Metode biologis merupakan metode sederhana dan ramah lingkungan yang dapat digunakan pada pembentukan nanopartikel ZnO. Pemanfaatan senyawa fitokimia dari ekstrak tanaman merupakan salah satu metode biologis yang dapat digunakan pada pembentukan nanopartikel ZnO. Senyawa fitokimia seperti senyawa fenolik dan flavonoid dapat mereduksi logam Seng menjadi nanopartikel Seng. Biji dan daun dari tanaman ketumbar (Coriandrum sativum L.) telah diketahui memiliki kandungan senyawa fenolik dan flavonoid. Tujuan dari penelitian ini adalah untuk mengetahui pengaruh perbedaan polaritas pelarut yang digunakan untuk ekstraksi biji dan daun ketumbar terhadap kapasitas reduksi ekstrak dan penangkal radikal bebas dari nanopartikel ZnO. Pelarut yang digunakan pada ekstraksi biji dan daun ketumbar adalah air deionisasi, etil asetat dan heksana. Perbedaan polaritas pelarut mempengaruhi berat nanopartikel ZnO yang diperoleh, hal ini disebabkan oleh perbedaan jenis senyawa fenolik dan flavonoid yang terekstrak. Perbedaan polaritas pelarut juga mempengaruhi kapasitas penangkal radikal bebas  dari nanopartikel ZnO. Ekstrak etil asetat daun ketumbar menghasilkan nanopartikel ZnO dengan berat 0,7907 g   dan aktivitas penangkal radikal bebas sebesar 11,16%/mg nanopartikel ZnO. Aktivitas penangkal radikal bebas nanopartikel ZnO menurun menjadi 3,67%/mg nanopartikel ZnO setelah dikalsinasi pada suhu 100oC dan menurun menjadi 0%/mg nanopartikel ZnO setelah dikalsinasi pada suhu 300oC, 500oC. Diameter nanopartikel ZnO meningkat dari 128,1±33,5 nm menjadi  552,3±61,1 nm setelah dikalsinasi Keywords: elektrokoagulasi, penurunan warna, penurunan TSS, laju degradasi COD, imbah tekstil
KAJIAN AKTIVITAS DAN STABILITAS ANTIOKSIDAN EKSTRAK KASAR BAWANG DAUN (Allium fistulosum L.) Tagor Marsillam Siregar; Eveline Eveline; Felita Anthony Jaya
Prosiding SNST Fakultas Teknik Vol 1, No 1 (2015): PROSIDING SEMINAR NASIONAL SAINS DAN TEKNOLOGI 6 2015
Publisher : Prosiding SNST Fakultas Teknik

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Abstract

Bawang  daun(Allium  fistulosum  L.)telah  diketahui memiliki potensi  sebagai sumber antioksidan alami namun penelitian tentang aktivitas antioksidan bawang daun  masih jarang  dilakukan. Pada penelitian ini bawang daun diekstraksi melalui metodemaserasi menggunakan tiga jenis pelarut dengan polaritas berbeda yaitu etanol (polar), etil asetat (semi polar) dan heksan (non polar) selama 4, 8 dan 12 jam.  Penentuan ekstrak kasar bawang daun terpilih dilakukan  berdasarkan hasil analisis aktivitas antioksidan, total fenolik dan total flavonoid dengan metode spektrofotometri. Selanjutnya ekstrak kasar bawang daun terpilih diuji stabilitasnya terhadap pH (4, 5, 6 dan 7) dan temperatur  (70,  80,  and  90ᴼC). Hasil penelitian menunjukkan bahwa ekstrak kasar bawang daun terpilih diperoleh dengan cara maserasi menggunakan pelarut etil asetat selama 12 jam.Ekstrak bawang daun tidak stabil terhadap perlakuan panas dan perubahan pH.Ekstrak bawang daun lebih stabil ketika berada pada kondisi suhu 70ᴼC dan pH 4-5. Uji  fitokimia  menunjukkan  bahwa bawang  daun  mengandung  senyawa golongan  tanin,  alkaloid,  fenolik,  flavonoid, dan  steroid. Hasil  analisis GC-MS terhadap ekstrak kasar bawang daun  terpilih  memperlihatkan adanya senyawa golongan fenolik, yaitu 2-methoxy-4-vinylphenol, golongan hidrokarbon seperti         2-tetradecene  dan  eicosane,  golongan asam lemak seperti asam linoleat dan asam linolenat,  golongan  diterpenoid  seperti neophytadiene,  dan  golongan  vitamin seperti vitamin E. Kata Kunci:Allium fistulosum L., antioksidan, maserasi, pH, stabilitas, temperatur
OPTIMASI PENAMBAHAN TEPUNG LIDAH BUAYA (Aloe vera (L.) Burm.f.) TERHADAP KARAKTERISTIK KWETIAU Tagor M. Siregar; Ruth Debora; Jeremia Manuel
Prosiding SNST Fakultas Teknik Vol 1, No 1 (2014): PROSIDING SEMINAR NASIONAL SAINS DAN TEKNOLOGI 5 2014
Publisher : Prosiding SNST Fakultas Teknik

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Abstract

Lidah buaya (Aloe vera) merupakan salah satu jenis tanaman yang memiliki kandungan serat pangan yang tinggi. Serat pangan telah diketahui memiliki berbagai manfaat untuk kesehatan manusia. Kwetiau merupakan produk pangan yang cukup digemari oleh masyarakat Indonesia namun memiliki kandungan serat pangan yang rendah. Penelitian ini bertujuan untuk menentukan jenis tepung dan konsentrasi substitusi tepung tapioka, maizena dan lidah buaya terbaik dalam meningkatkan kandungan serat dan karakteristik kwetiau.  Tepung lidah buaya dibuat dengan metode pengeringan cabinet dry pada suhu 600C. Penentuan formula kwetiau terbaik dilakukan dengan metode mixture experiment menggunakan software Design Expert 7.0 D-Optimal. Kwetiau yang dibuat dengan menggunakan tepung lidah buaya tanpa kulit (20%) menghasilkan karakteristik terbaik dan kadar serat pangan sebesar 6,7% sehingga digunakan sebagai dasar dalam optimasi pembuatan kwetiau. Hasil penelitian menunjukkan penambahan tepung tapioka (25,580%), maizena (64,233%), dan lidah buaya (10,187%) menghasilkan kwetiau dengan karakteristik terbaik serta memiliki kandungan serat pangan sebesar 5,54% Kata Kunci : Aloe vera, kwetiau, mixture experiment, serat pangan
STUDI AKTIVITAS ANTIOKSIDAN PADA TOMAT (Lycopersicon esculentum) KONVENSIONAL DAN ORGANIK SELAMA PENYIMPANAN Eveline Eveline; Tagor Marsillam Siregar; Sanny Sanny
Prosiding SNST Fakultas Teknik Vol 1, No 1 (2014): PROSIDING SEMINAR NASIONAL SAINS DAN TEKNOLOGI 5 2014
Publisher : Prosiding SNST Fakultas Teknik

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Abstract

Tomat (Lycopersicon esculentum) adalah buah yang banyak mengandung senyawa antioksidan (fenolik, flavonoid, vitamin C, dan likopen). Pada produk holtikultura, metode penanaman (konvensional dan organik) merupakan salah satu faktor yang mempengaruhi aktivitas antioksidan selain faktor masa simpan (0, 3, 6, 9, 12, dan 15 hari). Penelitian ini dirancang untuk mempelajari aktivitas antioksidan dan pengaruh masa simpan terhadap aktivitas antioksidan tomat konvensional dan tomat organik. Awal penelitian dilakukan penentuan pelarut ekstraksi terbaik (etanol dan aseton, 80%). Aseton 80% merupakan pelarut terpilih untuk mengekstrak komponen antioksidan tomat (rendemen 3,39%; IC50 1405,85 mg/100 g buah; total fenolik 11,53 mg GAE/100 g buah; flavonoid 1,81 mg QE/100 g buah; dan vitamin C 8,37 mg asam askorbat/100 g buah). Kandungan fenolik (masa simpan 3 hari) dan likopen didapati lebih tinggi pada tomat organik, sedangkan vitamin C lebih tinggi pada tomat konvensional (masa simpan 9 dan 15 hari). Aktivitas antioksidan tomat menurun pada penyimpanan hari ke-3, naik pada hari ke-6, kemudian kembali turun pada hari ke-9. Total fenolik tomat organik menurun pada hari ke-6, sedangkan tomat konvensional cenderung stabil selama penyimpanan. Kandungan flavonoid tomat menurun sejak penyimpanan hari ke-12. Vitamin C cenderung stabil selama penyimpanan (terutama tomat konvensional). Likopen meningkat selama 9 hari penyimpanan, setelah itu menurun. Kata kunci: antioksidan, konvensional, organik, penyimpanan, tomat
AKTIVITAS INHIBISI α-GLUKOSIDASE PADA MINUMAN FUNGSIONAL JAHE (Zingiber officinale Roscoe) DENGAN PENAMBAHAN EKSTRAK KULIT MELINJO KUNING (Gnetum gnemon Linn.) Tagor Marsillam Siregar; Aileen Neysha
FaST - Jurnal Sains dan Teknologi (Journal of Science and Technology) Vol 4, No 1 (2020): MAY
Publisher : Universitas Pelita Harapan

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Abstract

Yellow melinjo (Gnetum gnemon Linn.) peel extract contains active components such as resveratrol, tannin, steroid, flavonoid, and saponin. Ginger (Zingiber officinale Rosc.) also contains active components such as gingerol, paradol, and shogaol. These components in ginger and yellow melinjo peels are reported to have the activity to inhibit α-glucosidase. This research aim was to utilize yellow melinjo peel extract and ginger steep as functional drink that might have the activity to inhibit α-glucosidase. This research was divided into two stages. The preliminary stage was done to characterize yellow melinjo peel extract and ginger steep through activity inhibition of α-glucosidase, total phenolic, total flavonoid, and antioxidant activity. Main research was done to apply yellow melinjo peel extract and ginger steep into functional drink that use different concentration of yellow melinjo peel extract (0,12%, 0,16%, and 0,20%) and also using different concentration of stevia sweetener (0,3%; 0,4%; and 0,5%). All functional drinks’ formula was analyzed in organoleptic (scoring and hedonic), color, pH, and total soluble solids tests. The selected functional drink was analyzed for its activity of α-glucosidase inhibition, α-glucosidase inhibition kinetics, total phenolic, total flavonoid, and antioxidant activity. Yellow melinjo peel extract has activity inhibition of α-glucosidase (IC50)99.87 ppm, total phenolic 21.36 mg GAE/g, total flavonoid 11.97 mg QE/g, and antioxidant activity (IC50)1386.80 ppm. The ginger steep has activity inhibition of α-glucosidase (IC50)247811.5 ppm, total phenolic 0.29 mg GAE/g, total flavonoid 0.08 mg QE/g, and antioxidant activity IC50 60227.61 ppm. The selected functional drink from the hedonic test is the one with 0,20% extract and 0,5% stevia sweetener. The selected functional drink has inhibition of α-glucosidase IC50 194125 ppm, antioxidant activity (IC50)55497.12 ppm, total phenolic 0.64 mg GAE/mL, and total flavonoid 0.21 mg QE/mL.
Aplikasi Edible Coating dari Lidah Buaya dan Karagenan untuk Memperpanjang Umur Simpan Buah Tomat (Lycopersicum esculentum Mill.) Siregar, Tagor M.; Elysia, Vanessa
JURNAL AGROTEKNOLOGI Vol 18 No 1 (2024)
Publisher : Faculty of Agricultural Technology, University of Jember

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.19184/j-agt.v18i01.40104

Abstract

Tomato fruit (Lycopersicum esculentum Mill.) is a food material with a high water content so it is easy to decompose. This shows that efforts to prevent reduction in food quality can be developed in the form of edible coating from aloe vera gel with concentration of 0%, 30%, 40%, and 50%, and carrageenan with concentration of 1%, 2%, and 3%. The aims of this research were to determine the concentration of aloe vera gel and carrageenan based on the characteristics of edible film and to determine the effect of edible coating and storage time on the quality of tomato. The first stage of this research is making edible film based on analysis parameters such as water vapor transmission rate (WVTR), tensile strength, elongation, and thickness. The selected concentration used in the second stage of this research for making edible coating was 40% of aloe vera gel and 3% of carrageenan. The selected concentration has a WVTR value of 1.758±0.20 g.mm/m2.hour, tensile strength value of 0.248±0.00 N/cm2, elongation value of 25.164±0.10%, and thickness value of 0.074±0.00 mm. Tomato samples coated with edible coating and control tomatoes is stored for 9 days at room temperature (24-25oC and 65–70% relative humidity aproximately) and samples are analyzed every 3 days based on analysis parameters such as vitamin C content, weight loss, hardness level, pH, ohue, lycopene content, and total dissolved solids value. The application of edible coating and storage time can inhibit the decrease of vitamin C levels, lycopene levels, weight loss, hardness, also can inhibit the increase in pH value and total dissolved solids value. Meanwhile, the change in color (hue) of tomato is not affect by the use of edible coating. Keywords: aloe vera, carrageenan, edible coating, storage time, tomato
Adsorption of Indigo Carmine Dye and Copper Ion by Kaolin from Bangka Island Tahya, Candra Yulius; Cornelia, Melanie; Siregar, Tagor M.; Karnelasatri, Karnelasatri
Indonesian Journal of Chemical Research Vol 11 No 1 (2023): Edition for May 2023
Publisher : Jurusan Kimia, Fakultas Sains dan Teknologi, Universitas Pattimura

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.30598//ijcr.2023.11-tah

Abstract

Indigo Carmine (IC) is a synthetic dye that might promote irritations, vomiting, and diarrhea when orally consumed in high concentrations. Copper is a dangerous heavy metal that tends to accumulate in organisms' cells as a pollutant. Hyperproduction of IC and accumulation of copper in water could cause an environmental problem that must be adequately addressed. Kaolin is found abundant on Bangka Island. Based on XRD analysis, Kaolin Island from Bangka Island consists of two important minerals, Kaolinite and Rectorite. Kaolin has chemical and physical properties, which make it useful in several applications, including as an adsorbent. This study aims to evaluate how Kaolin can adsorb copper ion from acid wastewater (pH < 0.5) and determine natural Kaolin's ability to adsorb IC dye from an aqueous solution. Many factors, including mixing time and number of doses of Kaolin, influence Kaolin's ability to absorb IC. The longer the stirring time, the more IC is absorbed. The optimal temperature for IC adsorption is 25˚C. The optimal kaolin dose for IC adsorption is 20% (m/v). Copper concentration after application of Kaolin tends to decrease, with optimal at 25.09% (m/v) dosage for 19.23% copper removal.
Evaluating the Antioxidant Activity and Stability of Pigmented Rice Extract Siregar, Tagor M; Miarsa, Daniel C
Jurnal Teknik Pertanian Lampung (Journal of Agricultural Engineering) Vol. 13 No. 4 (2024): December 2024
Publisher : The University of Lampung

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.23960/jtep-l.v13i4.1036-1050

Abstract

This study aims to evaluate the antioxidant activity and stability of the extract of pigmented rice. Pigmented rice powder from 6 different varieties including Subang, Jowo Melik, Andel Abang, Bukittinggi, Cempo Merah, and Cempo Ireng) was macerated using ethanol with concentrations of 96% and 70%. Next, the rice extract was tested for stability to pH (1, 3, 5, 7, 9) and temperature (20°, 40°, 60°, 80°C). Results revealed that extract of Subang black glutinous rice using 96% ethanol resulted the highest antioxidant activity of 11.11±2.04 mg FeSO4/g, with an overall anthocyanin, flavonoids, phenolic contents of respectively 28.22±1.14 mg CE/g, 2.91±1.13 mg QE/g, and 3.46±1.59 mg GAE/g. The physiochemical properties of the rice extract were affected by the difference of pH. The increase in pH resulted in a decrease in antioxidant activity, total anthocyanin, and the values of color attributes (L*, a*, b*, C*, and ºHue) of the rice extracts. Temperature did not affect the physiochemical properties of the extract. The antioxidant activity, total anthocyanin, and color attributes of the rice extract were typically stable when the temperature rose from 20°C to 80°C. The extract at pH 1 and 80ºC treatment exhibited slightly higher yield based on antioxidant activity, total anthocyanin content, a* value, and ºHue with the values of 16.92±1.73 mg FeSO4/g, 33.90±2.33 mg CE/g, 21.55±0.54, and 30.04±0.57, respectively. Keywords: Anthocyanin, antioxidant activity, pH, pigmented rice, temperature.
Co-Authors . Hardoko A. Herry Cahyana Aileen Neysha Antonius Herry Cahyana Elysia, Vanessa Eveline Eveline Felita Anthony Jaya Jeremia Manuel Julian, Beatrice Karnelasatri, . Lausane, Aurelia Clara Liana Hendarto Melanie Cornelia, Melanie Miarsa, Daniel C Natalia , Natania, Natania Neysha, Aileen Regina Jessilia Gunawan Ruth Debora Sanaky, Florecita Sanny Sanny STELLA STELLA Tahya, Candra Yulius Teo, Claudius Titri Siratantri Mastuti Wijaya, Julia Ratna