Content uploaded by Harrizul Rivai
Author content
All content in this area was uploaded by Harrizul Rivai on Dec 12, 2015
Content may be subject to copyright.
Pengaruh Cara Pengeringan Oven dan Microwave terhadap Perolehan Kadar Senyawa Fenolat dan Daya Antioksidan dari Daun Jambu Biji (Psidii Folium) [Effects of Drying Method by Oven and Microwave on Gaining of Phenolic Compound and Antioxidant Activity from Guava Leaves (Psidii Leaves)]
Abstract
Effects of drying methods in gaining of extracted material, phenolic content, and antioxidant activity of guava leaves have been investigated. The drying methods tested were air-drying, microwave oven-drying, and oven-drying at 60 oC. The determination of extracted material compound showed that the air-drying, microwave oven-drying, and aven-drying at 60 oC contained 184.767, 333.767, and 208.533 mg/g, respectively. Phenolic content of these samples were 46.0474, 53.8402, and 51.4532 mg/g, respectively. IC50 of these sample were 0.529, 0.477, and 0.505 mg/mL, respectively. Among the drying methods tested, the highest extracted material, phenolic concentration, and antioxidant activity were by microwave oven-drying.
Keywords: drying method, microwave oven, guava leaves
... Ekstraksi pada bahan kering dimungkinkan menghasilkan ekstrak dengan rendemen senyawa antioksidan yang lebih tinggi dibandingkan pada bahan segar. Octavia, et al. (2010) melaporkan bahwa ekstrak dari bahan yang dikeringkan dengan microwave mempunyai senyawa fenolik yang lebih tinggi daripada bahan yang dikeringkan dengan oven. ...
... Hal ini disebabkan karena waktu pengeringan dengan microwave lebih singkat yaitu 4 menit sehingga senyawa yang bersifat termolabil seperti senyawa fenolik dan turunannya tidak terurai selama proses pengeringan. Sebaliknya, pengeringan bahan menggunakan oven berlangsung lebih lama yaitu selama 48 jam, sehingga memungkinkan adanya reaksi enzimatis yang terjadi selama proses pengeringan yang dapat mengakibatkan senyawa fenolik di dalam bahan akan terpolimerisasi dan teroksidasi sehingga kandungan total fenoliknya menjadi lebih rendah (Octavia et al. 2010) Berdasarkan Gambar 2, nilai TPC ekstrak daun torbangun tertinggi (60.16 mg GAE/g dw) didapatkan pada perlakuan PEF-microwave dengan kuat medan listrik 2.5 kV/cm. Nilai TPC ekstrak hasil perlakuan pengeringan dengan microwave maupun oven menunjukkan trend yang sama, yaitu TPC meningkat saat sampel di-pretreatment dengan PEF pada 1.5 hingga 2.5 kV/cm, namun kemudian nilai TPC menurun ketika kuat medan listrik dinaikkan. ...
Torbangun leaf (Coleus amboinicus L.) is an Indonesian plant containing phenolic and flavonoid compounds
that act as antioxidants. One method widely used to extract antioxidants from plants is maceration. However,
maceration has disadvantages such as time- and solvent-consuming also gives a low yield. Therefore, to solve these disadvantages, the extraction of antioxidant compounds from torbangun leaves has been done using
the maceration method with Pulsed Electric Field (PEF) as pretreatment. Before the extraction process, fresh
torbangun leaves were dried by using two methods: oven and microwave. Next, torbangun dried-leaves were
pretreated by using PEF at various electric field strengths (1.5; 2; 2.5; 3; and 3.5 kV/cm) for 20 seconds and
followed by a four hours maceration process. Total phenolic content (TPC) and total flavonoid content (TFC) of extracts were then analyzed using Folin Ciocalteau and Calorimetric AlCl3 methods, respectively. While antioxidant activity (IC50) was determined using 1,1-diphenyl-2-picrylhydrazyl (DPPH). The results showed that the best result was obtained on microwave-dried material with PEF pretreatment at 2.5 kV/cm, yielding extract yield of 18.85% with TPC, TFC and IC50 were 60.16 mg GAE/g dw, 34.94 mg QE/g dw, and 0.98 mg/ml, respectively.
ResearchGate has not been able to resolve any references for this publication.