Yohana S. Kusuma Dewi
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Mekanisme dan Kinetika Kuesing Aloe Emodin terhadap Fotooksida Asan Linoleat Dewi, Yohana S. Kusuma; Tranggono, Tranggono; Raharjo, Sri; Hastuti, Pudji
Agritech Vol 26, No 2 (2006)
Publisher : Faculty of Agricultural Technology, Universitas Gadjah Mada, Yogyakarta, Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (1533.688 KB) | DOI: 10.22146/agritech.9474

Abstract

To study the effects of methylene blue and aloe emodin on the photosensitized oxidation were prepared in methylene chloride systems. The oxidation of linoleic acid was determined by measuring the peroxide value. The quenching mechanism and kinetics of aloe emodin in methylene blue-sensitized photooxidation of linoleic acid were studied by the steady-state kinetic methods. The methylene blue consentration was produced signicantly increased of peroxide value on singlet oxygen oxydation of linoleic acid The effect of aloe emodin concentration on singlet oxygen oxidation of linoleic acid was produced signicantly decreased of peroxide value of linoleic acid.. The calculated quenching rate of aloe emodin was 4.68 x 109 11I1 S -1. Aloe emodin both of quenched singlet oxygen and sensitizer to reduce photosensitized oxidation of linoleic acid by the singlet oxygen quenching mechanism and the excited triplet oxygen sensitizer quenching mechanism. The ability of antiphotooxidant activity of aloe emodin was affected by concentration.
KARAKTERISTIK FISIKOKIMIA DAN SENSORI BROWNIES PANGGANG PADA BERBAGAI SUBSTITUSI TERIGU DENGAN TEPUNG KOMPOSIT DARI TEPUNG TALAS DAN TEPUNG PISANG KEPOK Kurniawan, Mikhael Ricky; Dewi, Yohana S. Kusuma; Lestari, Oke Anandika
Jurnal Sains Mahasiswa Pertanian Vol 6, No 2 (2017): Oktober 2017
Publisher : Jurnal Sains Mahasiswa Pertanian

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Abstract

ABSTRAK Penelitian ini bertujuan untuk mengetahui formulasi tepung komposit (tepung pisang kepok dan tepung talas) yang terbaik digunakan untuk substitusi terigu  pada pembuatan brownies panggang berdasarkan karakter fisikokimia dan sensori. Pembuatan brownies menggunakan bahan baku tepung komposit yang terbuat dari campuran tepung talas dan tepung pisang kepok. Pembuatan brownies menggunakan berbagai formulasi tepung, yaitu tepung terigu 100%, tepung pisang kepok 20% + tepung talas 60% + terigu 20%, tepung pisang kepok 30% + tepung talas 50% + terigu 20%, tepung pisang kepok 40% + tepung talas 40% + terigu 20%, tepung pisang kepok 50% + tepung talas 30% + terigu 20%, dan tepung pisang kepok 60% + tepung talas 20% + terigu 20%. Hasil menunjukan bahwa brownies substitusi terigu dengan tepung komposit berpengaruh nyata terhadap kadar air, kadar abu dan protein. Perlakuan terbaik adalah formulasi tepung pisang kepok 30 % +  tepung talas 50 % + terigu 20 % yang memiliki karakter fisikokimia yaitu kadar air 21,67 %, kadar abu 1,68 %, kadar lemak 25,58 %, kadar protein 6,35 %, kadar karbohidrat 44,55 % dan karakteristik sensori adalah warna 2,07 (putih keabu-abuan), aroma 3,10 (agak kuat) , tekstur 3,70 (agak empuk) dan rasa 4,27 (suka). Kata kunci : Brownies, Karakteristik, Pisang Kepok, Substitusi, Tepung, Talas, Tepung Komposit
Isolation and Identification of Antiradical and Anti-photooxidant Component of Aloe vera chinensis Dewi, Yohana S. Kusuma; Tranggono, Tranggono; Raharjo, Sri; Hastuti, Puji
Indonesian Food and Nutrition Progress Vol 12, No 1 (2005)
Publisher : Indonesian Association of Food Technologists

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22146/jifnp.30

Abstract

A potent antiradical and antiphotooxidant compound from Aloe vera chinensis was investigated. The results indicated that the methanolic extracts produced stronger antiradical and antiphotoaxidant activity also gave higher yields of extract than other organic solvents. Silica gel column separated methanolic extracts into five fractions. Of the five fractions, fraction II possessed significant antiradical activity (70.2 % inhibition on free radical DPPH) and its showed significant antiphotooxidant activity (60.1 % inhibition on hydroperoxide formation). Subsequently, fraction II was separated into eight subfractions by silica gel column. The sub fraction II-b exhibited stronger antiradical and antiphotooxidant activity than others and showed a single spot in thin layer chromatography Silica gel 60 F254 plates. On the basis of mass spectrophotometry in combination with reversed phased, high performance chromatography, this compound has been identified as 1,8 dihydroxy-3- hydroxymethylanthraquinone (Aloe emodin).