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POTENSI ANTIOKSIDAN EKSTRAK METANOL KULIT BATANG TUMBUHAN MANGROVE Sonneratia alba Herawati, Netti; Jalaluddin, Noor; Daha, La; Zenta, Firdaus
MAJALAH FARMASI DAN FARMAKOLOGI Vol 15, No 1 (2011)
Publisher : Universitas Hasanuddin

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Ekstrak metanol kulit batang tumbuhan mangrove Sonneratia alba dianalisis untuk menentukan aktivitas antioksidannya dengan metode DPPH. Ekstrak metanol ini  menun-jukkan aktivitas antioksidan yang kuat dengan nilai IC50 12,2 µg/ml. Aktivitas ini lebih tinggi dari aktivitas asam askorbat (vitamin C) yang digunakan sebagai kontrol positif dengan nilai IC50 sebesar 17,64 µg/ml. Dari hasil uji ini, disimpulkan bahwa S. alba berpotensi sebagai sumber antioksidan alami.
A Simple and Appropriate Dietary Scoring Method for Assessing Nutritional Quality of the Diet of Pregnant Women and Toddler Hardinsyah, .; Mailoa, Meitycorfrida; Herawati, Netti
Media Gizi dan Keluarga Vol 24, No 1 (2000): Jurnal Media Gizi dan Keluarga
Publisher : Media Gizi dan Keluarga

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The objective of this study was to identify a simple and appropriate dietary scoring method for assessing nutritional quality of the diet of pregnant women and toddler. For this purpose, two sets of food intake data were analyzed. The first data set was the food intake data of pregnant women, which consisted of 150 pregnant women (3-8 month of pregnancy) of East Bogor, and the second data set was the food intake data of toddler which consisted of 191 toddlers (1-3 years) of rural West Java. Four simple dietary scoring methods were developed based on a dietary scoring system of the five major food groups (cereals, meats, vegetables, fruit and milk) and the six major food groups (cereals, meat, legumes, vegetables, fruit and milk). Nutritional quality of the diet (NQ) which was defined as the mean nutrient adequacy of eight nutrients was considered as the gold standard for analysing the most appropriate dietary scoring method. Correlation and dummy regression was applied for this analysis. The results showed that each of the dietary scoring method developed was significantly correlated with the NQ with correlation coefficients ranging from 0.58 to 0.80. The most appropriate and simplest dietary scoring method for assessing the NQ of pregnant women and toddlers was the dietary scoring method developed based on the six major food groups and applying three categorical levels of dietary score (0, 1,2.).
PERBANDINGAN KUASA UJI PENDEKATAN BIGGERS DAN SATTERTHWAITE-COCHRAN DALAM MENGANALISIS DATA HILANG PADA RANCANGAN KELOMPOK TERACAK LENGKAP Firdaus, Achmad; Usman, Mustofa; Herawati, Netti
FORUM STATISTIKA DAN KOMPUTASI Vol 8, No 1 (2003)
Publisher : FORUM STATISTIKA DAN KOMPUTASI

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This study was aimed to compare type I error in estimating missing data by Biggers and Satterhwaite-Cochran methods in  Randomized Comple Block Design.  Simulation study using Gauss software showed that type I error for Biggers approach are over estimate.  The problem  can be overcomed by Satterhwaite-Cochran approach.Keyword:  Missing data, randomized Block design, Biggers, Satterhwaite-Cochran.
Total Fenol dan Aktivitas Antioksidan dari Sonneratia alba Bark Herawati, Netti
SAINSMAT Vol 1, No 1 (2012): Maret
Publisher : SAINSMAT

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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  
Potensi Antioksidan Ekstrak Kloroform Kulit Batang Tumbuhan Mangrove (Sonneratia alba) Herawati, Netti
C H E M I C A Vol 12, No 1 (2011)
Publisher : Jurusan Kimia FMIPA UNM

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ABSTRAK Ekstrak kloroform kulit batang tumbuhan mangrove Sonneratia alba dianalisis untuk menentukan aktivitas antioksidannya dengan metode DPPH. Ekstrak kloroform ini  menunjukkan aktivitas antioksidan yang kuat dengan nilai IC50 41,9 µg/ml. Aktivitas antioksidan ekstrak kloroform tersebut termasuk kuat berdasarkan kriteria Blois (<100 µg/mL termasuk antioksidan kuat), namun aktivitas ini lebih rendah dari control positif yang digunakan (asam askorbat) dengan nilai IC50 sebesar 17,64 µg/mL. Dari hasil uji ini, disimpulkan bahwa S. alba berpotensi sebagai sumber antioksidan alami. Kata kunci: Sonneratia alba, antioksidan, mangrove ABSTRACT Chloroform extract of the bark of mangrove Sonneratia Alba were analyzed to determine theantioxidant activity by DPPH method. Chloroform extract showed strong antioxidant activitywith IC50 value is 41.9 µg/ml. The antioxidant activity of chloroform extract was strongly based on criteria including Blois (<100 µg/mL included a powerful antioxidant), but this activity is lower than the positive control used (ascorbic acid) with IC50 values​​ of 17.64 mg/mL. From the results of this test, it was concluded that S.alba potential as asource of natural antioxidants. Key words: Sonneratiaalba, antioxidants, mangrove.
Identifikasi Senyawa Bioaktif Tumbuhan Mangrove Sonneratia alba Herawati, Netti
C H E M I C A Vol 12, No 2 (2011)
Publisher : Jurusan Kimia FMIPA UNM

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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
Pengujian Antiradikal Bebas Difenilpikril Hidrazil (DPPH) Kulit Batang Sonneratia alba Herawati, Netti
C H E M I C A Vol 13, No 1 (2012)
Publisher : Jurusan Kimia FMIPA UNM

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Berbagai tumbuhan mangrove telah digunakan oleh masyarakat secara tradisional untuk mengobati luka, penyakit kulit, mencegah bengkak, dan pengawet minuman tradisional yang sebagian berhubungan dengan mekanisme radikal bebas. Dengan demikian, agar pemanfaatannya dapat lebih dipertanggung jawabkan dan dikembangkan maka perlu dilakukan evaluasi terhadap aktivitas penangkapan radikal bebasnya. Dalam penelitian ini, aktivitas penangkapan radikal ekstrak metanol dan etil asetat Sonneratia alba diuji dengan menentukan aktivitas penangkapan radikal bebas DPPH (Diphenylpicryl Hydrazyl). Hasil penelitian menunjukkan bahwa ekstrak metanol dan etil asetat kulit batang S. alba memiliki aktivitas penangkapan radikal bebas yang kuat, dan melebihi asam askorbat (control) dengan IC50 berturut-turut sebesar 11,66 μg/ml, 12,45 μg/ml dan 17,64 μg/ml. Kata kunci: Antiradikal, DPPH, Sonneratia alba ABSTRACT Various mangroves has been traditionally used by people to treat wounds, skin diseases, prevent swelling, and preservatives traditional drink common associated with free radical mechanism. Thus, to be more accountable and developed by, it needs to evaluate the capture activity of free-radical. In this study, the capture activity of radical methanol and ethyl acetate extracts Sonneratia alba was tested by determining the capture activity of free radical DPPH arrest (Diphenylpicryl Hydrazyl). The results showed that the capture activity of methanol and ethyl acetate extracts from leather trunk of S. alba had stronger than ascorbic acid (control) IC50, respectively for 11.66 ug / ml, 12.45 microg / ml and 17.64 ug / ml. Keywords: Antiradikal, DPPH, Sonneratia alba
Testing Normality and Bandwith Estimation Using Kernel Method For Small Sample Size Herawati, Netti; Nisa, Khoirin
Jurnal ILMU DASAR Vol 10, No 1 (2009)
Publisher : Fakultas MIPA Universitas Jember

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This article aimed to study kernel method for testing normality and to determine the density function based oncurve fitting technique (density plot) for small sample sizes. To obtain optimal bandwith we used Kullback-Leibler cross validation method. We compared the result using goodness of fit test by Kolmogorof Smirnov teststatistics. The result showed that kernel method gave the same performance as Kolmogorof Smirnov for testingnormality but easier and more convinient than Kolmogorof Smirnov does.Keywords: Normality, kernel method, bandwith, Kolmogorof Smirnov test
PENGARUH MODEL PEMBELAJARAN DAN KESADARAN METAKOGNISI TERHADAP HASIL BELAJAR PESERTA DIDIK KELAS X SMA ISLAM KOTA TERNATE (Pokok Bahasan Ikatan Kimia) Sonyinga, Desma; Danial, Muhammad; Herawati, Netti
Chemistry Education Review (CER) Volume 2 Nomor 1 September 2018
Publisher : Program Pasca Sarjana UNM

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Abstract

Penelitian ini merupakan penelitian eksperimen semu yang bertujuan untuk mengetahui pengaruh model pembelajaran dan kesadaran metakognisi terhadap hasil belajar peserta didik kelas X SMA Islam Kota Ternate pada pokok bahasan ikatan kimia. Penelitian ini menggunakan rancangan Desain penelitian faktorial 2x2. Sampel terdiri atas dua kelas yang dipilih dengan random sampling teknik acak kelas. Kelas X IPA 1 sebagai kelas eksperimen 1 dibelajarkan dengan model pembelajaran inkuiri terbimbing dan kelas X IPA 2 sebagai kelas eksperimen 2 dibelajarkan dengan model pembelajaran berbasis masalah. Instrument penelitian yang digunakan yaitu angket inventori kesadaran metakognisi dan tes hasil belajar. Data yang diperoleh dianalisis secara inferensial dan deskriptif. Hasil analisis inferensial diperoleh bahwa: (1) model pembelajaran berpengaruh terhadap hasil belajar peserta didik dengan nilai signifikansi yang diperoleh yaitu 0,01<0,05. (2) kesadaran metakognisi berpengaruh terhadap hasil belajar peserta didik dengan nilai signifikansi yang diperoleh yaitu 0,008<0,05. (3) terdapat interaksi model pembelajaran dengan kesadaran metakognisi, terlihat pada nilai signifikansi yang diperoleh yaitu 0,014<0,05. Selanjutnya hasil analisis deskriftif diperoleh bahwa: (1) rata-rata nilai hasil belajar peserta didik yang menggunakan model pembelajaran inkuiri terbimbing hasilnya lebih tinggi dibandingkan dengan model pembelajaran berbasis masalah. (2) rata-rata nilai hasil belajar peserta didik dengan kesadaran metakognisi tinggi, lebih tinggi dibandingkan dengan rata-rata nilai hasil belajar dengan kesadaran metakognisi rendah, dan (3) terjadi interaksi interaksi antara model pembelajaran dan kesadaran metakognisi dalam mempengaruhi hasil belajar peserta didik kelas X IPA SMA Islam Kota Ternate. Jadi, ada pengaruh antara model pembelajaran dan kesadaran metakognisi terhadap hasil belajar peserta didik kelas X SMA Islam Kota Ternate pada pokok bahasan ikatan kimia.
Studi Pemanfaatan Pati Sagu (Metroxylon Sp) dan Daging Ikan Belut (Monopterus Albus) Dalam Pembuatan Sosis Fadmi, Andriyani; Herawati, Netti; Restuhadi, Fajar
Jurnal Online Mahasiswa (JOM) Bidang Pertanian Vol 1, No 1 (2014): Wisuda Februari Tahun 2014
Publisher : Jurnal Online Mahasiswa (JOM) Bidang Pertanian

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This research to get formulation the best of sausage from benefit of sago essence and meat of eel.  This research was carried out experiments using a Completely Randomized Design (CRD) with 4 treatments and 4 replications in order to obtain 16 experimental units. The data obtained were statistically analyzed using Analysis of Variance (ANOVA). If the calculated F is greater than or equal to F table then continued with DNMRT test at 5% level. Sensory evaluation data show that by using PCA and cluster analysis, evaluation organoleptic by analysis hedonic with spider web to see attribute that protrude from every treatment. According to proceeds of chemists analysis and organoleptic experiment the best sausage get from 5% tapioca essence and 10% sago essence so that  treatment of TSB3 by characteristic like: activity of water 71,25%, activity of ashes 1,8%, activity of protein 8,9 %, activity of fat, activity 4,80%, carbohydrate 13,12% and experiment of color hedonic 2,24 %. Organoleptic evaluation by hedonic toward color 2,24 (rather agree), taste 1,97 (rather agree),  2,74 (rather agree) form 2,28 (rather agree) and over all evaluation 2,22 (rather agree) then organolepic evaluation by descriptive to color 2,52 (white grey), taste 2,20 (rather taste of eel), 2,43(rather stink), form 2,35 (elastic).   Kata kunci: susu fermentasi, Lactobacillus plantarum 1 R.11.1.2, kacang hijau dan kacang kedelai. Keywords: Sosis, Pati Sagu, Belut.