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Uji Aktivitas Antioksidan Ekstrak Etanol Rambut Jagung (Zea mays L.) dengan Menggunakan Metode 2,2-difenil-1-pikrilhidrazil (DPPH) Kurnia Kurnia; Muh Yunus; Netti Herawati
Chemica: Jurnal Ilmiah Kimia dan Pendidikan Kimia Vol 22, No 2 (2021): Chemica
Publisher : Jurusan Kimia FMIPA UNM

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (599.92 KB) | DOI: 10.35580/chemica.v22i2.26210

Abstract

ABSTRAKPengujian aktivitas antioksidan pada ekstrak etanol Rambut Jagung (Zea Mays L.) yang telah dilakukan dengan menggunakan metode DPPH (2,2-difenil-1-pikrilhidrazil). Sebagai kontrol positif digunakan vitamin C. Ekstrak etanol  diperoleh dengan metode maserasi. Aktivitas antioksidan sampel ditentukan oleh besarnya persentase peredaman radikal DPPH. Ekstrak etanol rambut jagung memiliki aktivitas antioksidan lebih tinggi dibanding dengan vitamin C sebesar 7,73 ppm dan masuk dalam kategori sangat kuat. Kata kunci : DPPH, Rambut Jagung, Uji Aktvitas Antioksidan, (Zea mays L.). ABSTRACTThe antioxidant activity test of ethanol corn hair (Zea Mays L.) extract has been done by using DPPH (2,2-diphenyl-1-picrylhydrazyl). As a positive control used vitamin C. The ethanol extract is obtained by maceration method. The antioxidant activity of the sample is determined by the percentage of DPPH radical reduction. Ethanol corn hair extract has higher antioxidant activity than vitamin C at 7.73 ppm and in the category of very strong.Keywords: Antioxidant Activity Test, DPPH, Hair Corn, (Zea mays L.).
Isolasi dan Identifikasi Senyawa Metabolit Sekunder Ekstrak n-Heksana Batang Benalu (Dendrophthoe falcata (L.f) Ettingsh) Herianti Hasbullah; Sudding Sudding; Netti Herawati
Chemica: Jurnal Ilmiah Kimia dan Pendidikan Kimia Vol 20, No 2 (2019)
Publisher : Jurusan Kimia FMIPA UNM

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (722.334 KB) | DOI: 10.35580/chemica.v20i2.13635

Abstract

ABSTRAK Penelitian ini adalah penelitian eksplorasi yang bertujuan untuk mengisolasi senyawa metabolit sekunder yang terdapat dalam ekstrak n- heksana batang benalu pohon kakao Dendrophthoe falcata (L.f) Ettingsh, yang berasal dari Desa Cendana, Kec. Burau, Kab. Luwu Timur Makassar, Sulawesi Selatan. Isolasi dilakukan dalam beberapa tahap yaitu maserasi, partisi dengan n-heksana, fraksinasi, uji kemurnian dan identifikasi. Hasil penelitian berupa isolat murni berbentuk kristal jarum berwarna putih dengan titik leleh 1400C. Hasil uji dengan pereaksi wagner membentuk endapan cokelat. Identifikasi dengan spektrum infra merah yang menunjukkan bilangan gelombang (cm-1) yakni: 3550,95 (N-H); 1696,36 (C=O); 1303,88 (CN), 2945,30 dan 2856,58 (CH alifatik), 883,40 (C-H aromatik), 1454,33 (C=C). Berdasarkan hasil IR dan Uji warna menunjukkan bahwa isolat diduga senyawa golongan alkaloid. Kata kunci : Isolasi Dendrophthoe falcata (L.f) Ettingsh, senyawa alkaloid ABSTRACT This study is exploratory research that aimed to isolate and identify the secondary metabolite compound contained in the n-hexane extract of D.falcata (L.f) Ettingsh from Cendana village, Burau district, Luwu Timur Regency of Makassar. Isolation is done in several stages; maceration, partitioning with n-hexane, fractionation, purification and dentification. The result was in pure needle crystal shape with a melting point of 140,2°C. The test result with the Wagner reagent test showed the formation of a brown precipited. Analyzing of IR Spectrum of Isolate showed Several wave numbers; 3550,95 (N-H); 1696,36 (C=O); 1303,88 (CN), 2945,30 dan 2856,58 (CH alifatik), 883,40 (C-H aromatik), 1454,33 (C=C). Based on the result of IR datas and reagen test it is suggest that the isolate is alkaloid compound. Keywords : Isolation, Dendrophthoe falcata (L.f) Ettingsh, alkaloid compound
Identifikasi Senyawa Bioaktif Tumbuhan Mangrove Sonneratia alba Netti Herawati
Chemica: Jurnal Ilmiah Kimia dan Pendidikan Kimia Vol 12, No 2 (2011)
Publisher : Jurusan Kimia FMIPA UNM

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (225.62 KB) | DOI: 10.35580/chemica.v12i2.501

Abstract

Penelitian ini bertujuan untuk mengisolasi dan mengidentifikasi senyawa yang terkandung dalam kulit batang Sonneratia alba. Serbuk kulit batang S. alba dimaserasi dengan metanol menghasilkan ekstrak coklat pekat yang selanjutnya difraksinasi dengan n-heksan, kloroform, dan etil asetat. Serangkaian proses kromatografi kolom dilakukan pada fraksi etil asetat yang dilanjutkan dengan  rekristalisasi, dan penentukan titik leleh. Senyawa diperoleh sebagai serbuk berwarna coklat yang terdekomposisi pada 325 ºC, dan positif terhadap uji fenolat. Spektrum UV(MeOH) menunjukkan serapan maksimum pada  248 nm. Spektrum IR menunjukkan puncak serapan yang kuat pada 3277, 3232, 2953, 1730, 1612, dan 1354 cm-Berdasarkan data tersebut, maka senyawa yang diperoleh termasuk senyawa golongan fenolik dengan cincin lakton.Kata Kunci : Sonneratia alba, senyawa bioaktif, isolasi, mangroveABSTRACT This research aimed at isolating and identifying compounds in the stem bark of Sonneratia alba. The stem bark powder of S. alba was macerated with methanol to yield a dark brown extract which was then fractionated with n-hexane, chloroform, and ethyl acetate. Several colom chromatoghrafi processes was carried out on ethyl acetate fraction that was continued by furification with crystallization and melting point  determination. Compound was obtained as a brown amorphous powder decomposed at 325 ºC and gave a positive respon to fenolic assay. UV(MeOH) spectrum showed maximum absorbance at 248 nm. IR spectrum presents several peaks at 3277, 3232, 2953, 1730, 1612, dan 1354 cm-1. Base from datas, it concluded that the compound  is fenolic with lactone ring. Key Word: Sonneratia alba, bioactive compound, isolation, mangrove
Sintesis Nanopartikel Perak Menggunakan Bioreduktor Ekstrak Daun Teh Hijau (Camellia Sinensis) dengan Iradiasi Microwave Dewi Mustika Rahim; Netti Herawati; Hasri Hasri
Chemica: Jurnal Ilmiah Kimia dan Pendidikan Kimia Vol 21, No 1 (2020)
Publisher : Jurusan Kimia FMIPA UNM

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (3733.104 KB) | DOI: 10.35580/chemica.v21i1.14835

Abstract

ABSTRAK Telah dilakukan penelitian tentang sintesis nanopartikel perak menggunakan bioreduktor ekstrak daun teh hijau (Camellia Sinensis) dengan iradiasi microwave. yang untuk mengetahui pengaruh waktu sintesis dan pengaruh pH stabilizer terhadap sintesis nanopartikel perak ekstrak daun teh hijau dengan iradiasi microwave serta karakterisasinya. Larutan AgNO3 3 mM direduksi menggunakan ekstrak daun teh hijau dan di iradiasi microwave pada variasi waktu sintesis 1-5 menit. Penentuan waktu sintesis optimal menggunakan spektrofotometer UV-Vis diukur setiap 1 menit. Nanopartikel dengan waktu sistesis 4 menit, pH stabilizer menggunakan asam sitrat dan NaOH dengan pH 6-9. Karakterisasi nanopartikel menggunakan instrumen SEM-EDS (Scanning Electron Microscopy-Energy Dispersive X-Ray Spectroscopy) dan PSA (Particle Size Analyzer). Hasil penelitian menunjukkan bahwa waktu sintesis optimal adalah 4 menit. Morfologi nanopatikel perak yang dikarakterisasi menggunakan SEM (Scanning Electron Microscopy) yang dihasilkan cenderung beragregasi. Adanya kecenderungan nanopartikel untuk beragregasi menyebabkan ukuran atau diameter nanopartikel tidak seragam. Ukuran dan distribusi ukuran nanopartikel perak dikarakterisasi menggunakan PSA(Particle Size Analyzer) dihasilkan pada pH 6 antara 31,01 – 402,44 nm dengan rata-rata ukuran sebesar 91 nm, pH 7 antara 35,03 – 740,899 nm dengan rata-rata ukuran sebesar 106,3 nm, pH 8 antara 39,58 – 193,48 nm dengan rata-rata ukuran 71,7, dan pH 9 antara 35,03 – 171,25 nm dengan rata-rata ukuran sebesar 64,4 nm. Disimpulkan bahwa hasil sintesis nanopartikel perak terkecil diperoleh pada pH 9 dan waktu sintesis 4 menit. Kata kunci: Ekstrak Daun Teh Hijau, Nanopartikel Perak, Iradiasi Microwave ABSTRACT Research has been carried out on the synthesis of silver nanoparticles using a bioreductor of green tea leaf extract (Camellia Sinensis) by irradiation microwave.This research aimed to determine the effect of synthesis time and pH stabilizer on the synthesis of silver nanoparticles of green tea leaf extract by microwave irradiation and it’s characterization. The 3 mM AgNO3 solution was reduced using green tea leaf extract and microwave irradiated in a variation of the synthesis time 1-5 minutes. The determining optimum of sythesis time was done by analysis of UV-Vis spectrum for every minutes. Nanoparticles with a synthesis time of 4 minutes, the stabilizer of silver nanoparticles used citric acid and NaOH with a pH of 6-9. Characterization of nanoparticles using SEM-EDS instrument (Scanning Electron Microscopy-Energy Dispersive X-Ray Spectroscopy) and PSA (Particle Size Analyzer). The results showed that the optimal synthesis time was 4 minutes. The morphology of silver nanopaticles characterized using SEM produced tends to aggregate. The tendency of nanoparticles to aggregate causes size or diameter of nanoparticles was random. The size and distribution of size silver nanoparticles characterized using PSA were produced at pH 6 between 31.01 - 402.44 nm with an average size of 91 nm, pH 7 between 35.03 - 740,899 nm with an average size amounting to 106.3 nm, pH 8 between 39.58 - 193.48 nm with an average size of 71.7, and pH 9 between 35.03 - 171.25 nm with an average size of 64.4 nm. It was concluded that the synthesis of the smallest silver nanoparticles was obtained at pH 9 and synthesis time of 4 minutes. Keywords: Green Tea Leaf Extract, Silver Nanoparticles, Microwave Irradiation
Sintesis Nanopartikel Perak Menggunakan Bioreduktor Ekstrak Daun Teh Hijau (Camellia Sinensis) dengan Iradiasi Microwave. Dewi Mustika Rahim; Netti Herawati; Hasri Hasri
Chemica: Jurnal Ilmiah Kimia dan Pendidikan Kimia Vol 22, No 2 (2021): Chemica
Publisher : Jurusan Kimia FMIPA UNM

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (3604.038 KB) | DOI: 10.35580/chemica.v22i2.26207

Abstract

ABSTRAKTelah dilakukan penelitian tentang sintesis nanopartikel perak menggunakan bioreduktor ekstrak daun teh hijau (Camellia Sinensis) dengan iradiasi microwave. yang untuk mengetahui pengaruh waktu sintesis dan pengaruh pH stabilizer terhadap sintesis nanopartikel perak ekstrak daun teh hijau dengan iradiasi microwave serta karakterisasinya. Larutan AgNO3 3 mM direduksi menggunakan ekstrak daun teh hijau  dan di iradiasi microwave pada variasi waktu sintesis 1-5 menit. Penentuan waktu sintesis optimal menggunakan spektrofotometer UV-Vis diukur setiap 1 menit. Nanopartikel dengan waktu sistesis 4 menit,  pH stabilizer menggunakan asam sitrat dan NaOH dengan pH 6-9. Karakterisasi nanopartikel menggunakan instrumen SEM-EDS (Scanning Electron Microscopy-Energy Dispersive X-Ray Spectroscopy) dan PSA (Particle Size Analyzer). Hasil penelitian menunjukkan bahwa waktu sintesis optimal adalah 4 menit. Morfologi nanopatikel perak yang dikarakterisasi menggunakan SEM (Scanning Electron Microscopy) yang dihasilkan cenderung beragregasi. Adanya kecenderungan nanopartikel untuk beragregasi menyebabkan ukuran atau diameter nanopartikel tidak seragam. Ukuran dan distribusi ukuran nanopartikel perak dikarakterisasi menggunakan PSA(Particle Size Analyzer) dihasilkan pada pH 6 antara 31,01 – 402,44 nm dengan rata-rata ukuran sebesar 91 nm, pH 7 antara 35,03 – 740,899 nm dengan rata-rata ukuran sebesar 106,3 nm, pH 8 antara 39,58 – 193,48 nm dengan rata-rata ukuran 71,7, dan pH 9 antara 35,03 – 171,25 nm dengan rata-rata ukuran sebesar 64,4 nm. Disimpulkan bahwa hasil sintesis nanopartikel perak terkecil diperoleh pada pH 9 dan waktu sintesis 4 menit.Kata kunci: Ekstrak Daun Teh Hijau, Nanopartikel Perak, Iradiasi Microwave.  ABSTRACTResearch has been carried out on the synthesis of silver nanoparticles using a bioreductor of green tea leaf extract (Camellia Sinensis) by irradiation microwave.This research aimed to determine the effect of synthesis time and pH stabilizer on the synthesis of silver nanoparticles of green tea leaf extract by microwave irradiation and it’s characterization. The 3 mM AgNO3 solution was reduced using green tea leaf extract and microwave irradiated in a variation of the synthesis time 1-5 minutes. The determining optimum of sythesis time was done by analysis of UV-Vis spectrum for every minutes. Nanoparticles with a synthesis time of 4 minutes, the stabilizer of silver nanoparticles used citric acid and NaOH with a pH of 6-9. Characterization of nanoparticles using SEM-EDS instrument (Scanning Electron Microscopy-Energy Dispersive X-Ray Spectroscopy) and PSA (Particle Size Analyzer). The results showed that the optimal synthesis time was 4 minutes. The morphology of silver nanopaticles characterized using SEM produced tends to aggregate. The tendency of nanoparticles to aggregate causes size or diameter of nanoparticles was random. The size and distribution of size silver nanoparticles characterized using PSA were produced at pH 6 between 31.01 - 402.44 nm with an average size of 91 nm, pH 7 between 35.03 - 740,899 nm with an average size amounting to 106.3 nm, pH 8 between 39.58 - 193.48 nm with an average size of 71.7, and pH 9 between 35.03 - 171.25 nm with an average size of 64.4 nm. It was concluded that the synthesis of the smallest silver nanoparticles was obtained at pH 9 and synthesis time of 4 minutes.Keywords: Green Tea Leaf Extract, Silver Nanoparticles, Microwave Irradiation
Isolasi dan Identifikasi Senyawa Metabolit Sekunder Ekstrak Etil Asetat Kulit Batang Mangrove Pedada (Sonneratia caseolaris) Ita Hasmila; Muhammad Danial; Netti Herawati
Chemica: Jurnal Ilmiah Kimia dan Pendidikan Kimia Vol 20, No 1 (2019)
Publisher : Jurusan Kimia FMIPA UNM

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (578.226 KB) | DOI: 10.35580/chemica.v20i1.13616

Abstract

ABSTRAK Penelitian eksplorasi ini bertujuan untuk mengisolasi dan mengidentifikasi senyawa metabolit sekunder dari ekstrak etil asetat kulit batang mangrove Sonneratia caseolaris yang diperoleh dari daerah pinggiran Sungai Tallo Kelurahan Paccerakkang, Kota Makassar, Sulawesi Selatan. Isolasi dilakukan dalam beberapa tahap yaitu maserasi, partisi, fraksinasi, uji kemurnian dan identifikasi. Hasil penelitian berupa isolat murni berbentuk serbuk berwarna cokelat muda yang terdekomposisi pada suhu 140 0C. Pengujian dengan FeCl3 menunjukkan bahwa isolat positif flavonoid. Hal ini didukung oleh beberapa data spektrum FTIR pada isolat yang menunjukkan bilangan gelombang (cm- 1) yakni: 3380.93 (OH), 2954.95 (OH asam karboksilat), 1697.36 (C=O asam karboksilat), 1606.7 (C=C alkena); 2926.01 dan 2852.72 (CH3 dan CH2); 1359.82 (NO2); 1446.61 (C=C aromatik), 1211.3; 1188.15 dan 1037.7 (C-O alkohol) dan 1107.14 (C−O aril eter). Kata kunci: Isolasi, Etil Asetat, Sonneratia caseolaris, Flavonoid ABSTRACT This exploratory research have aim to isolate and identification the secondary metabolite compound contained in the etil acetate extract bark of Sonneratia caseolaris from Tallo River side, Paccerakkang district, Makassar City, South Sulawesi. Isolation were doned in several stages, were maceration, partitioning, fractionation, purity testing and identification. The result was obtained of pure isolate, it was light-brown powder with decompotition of 1400C. Identification result with FeCl3 test showed this isolate was flavanoid compound. It obtained with data spectrum of infrared result, where isolate showed several wave number (cm-1) were: 3380.93 (OH), 2954.95 (OH acid carboxilate), 1697.36 (C=O acid carboxilate), 1606.7 (C=C alchena); 2926.01 and 2852.72 (CH3 and CH2); 1359.82 (NO2); 1446.61 (C=C aromatic), 1211.3; 1188.15 and 1037.7 (C-O alcohol); 1107.14 (C−O aril eter). Keywords: Isolation, Etil Acetate, Sonneratia caseolaris, Flavonoid
Total Fenol dan Aktivitas Antioksidan dari Sonneratia alba Bark Netti Herawati
Sainsmat : Jurnal Ilmiah Ilmu Pengetahuan Alam Vol 1, No 1 (2012): Maret
Publisher : Fakultas Matematika dan Ilmu Pengetahuan Alam Universitas Negeri Makassar

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.35580/sainsmat114632012

Abstract

DOWNLOAD PDFThe aim of this research was to examine the total phenolic content and radical scavenging capacity related to antioxidant potential in different fractions of methanolic extract of mangroves trees, Sonneratia alba bark. Total phenolic content was determined by the  Folin-Ciocalteau method.  Antioxidant  potential  has  been determined  as  the  free radical scavenging ability using a stable radical, diphenyl-picryl-hydrazyl (DPPH). Three fractions  of methanol extracts of S. alba were subjected to free radical scavenging activity in order to evaluate their antioxidant activity. The free radical scavenging activity of different fractions obtained from successive fractionation of methanol extracts with organic solvents of different polarities; hexane, chloroform, and ethyl acetate. Total phenolics content of three fraction and crude extract are 17.84 ±0.974, 156.310 ±0.703, 226.89 ±0.605, 249.56  ±0942 (GAE μg/g) respectively for hexane, chloroform, ethyl acetate, and crude extracts (methanol extract). Antioxidant assay showed that the ethyl acetate and chloroform fractions have the high activity with IC50 10.27 μg/ml and 27.34 μg/ml, respectively, while  a weak activity was showed by hexane fraction with 147 μg/ml. Linear correlation between the total antioxidant capacity of the fractions and the total phenolic contents was observed (r2=0.918). This data indicated that the antioxidant activity  mainly due to phenolic compound contain in those fraction. The results indicate promising S.alba or the utilization as significant source of natural antioxidant. Key words: Sonneratia alba,  total phenolics,  radical scavenging activity, antioxidant,  DPPH