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Journal : Jurnal Natural

NUTRITIONAL COMPOSITION OF DIOSCOREA HISPIDA FROM DIFFERENT LOCATIONS AROUND LEUSER ECOSYSTEM AREA Sitti Saleha; Nurdin Saidi; Saiful .; Murniana .; Saida Rasnovi; Teuku M. Iqbalsyah
Jurnal Natural Volume 18, Number 1, February 2018
Publisher : Universitas Syiah Kuala

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (174.348 KB) | DOI: 10.24815/jn.v18i1.8504

Abstract

Proximate analysis of Dioscorea hispida tubers, collected from five locations around Leuser ecosystem in Aceh Province, showed variations amongst samples. Standard AOAC method for proximate analysis of the fresh weight showed that the water content varied between 15.8 - 37.8%, crude protein 1.13 -6.20%, crude lipid 1.99 - 9.36% and ash 0.29 - 1.24%. The total carbohydrate was high, i.e. between 58.3 -71.9%. The main mineral was phosphorus, with a value of 11.7 - 46.9 mg/100g. These variations could be due to soil, climate and weather factors, as well as postharvest handling. Phytochemical tests showed that all of the samples contained alkaloids and terpenoids. One of the samples (LP) also contained phenol and steroid. The high cyanide content in the tubers (379 - 739 ppm) was easily removed by repeated washing. The cyanide level dropped significantly after the 3rd wash. Information on nutritional content in D. hispida is essential for planning its utilization. Increasing the economic value of D. hispida is expected to attract people around the Leuser ecosystem to cultivate and utilize it, thereby reducing illegal forest encroachment.Keywords: Dioscorea hispida, proximate, Leuser, janeng, gadung, starchREFERENCESBarton H 2014 Yams: Origins and Development, Encyclopaedia of Global Archaeology, p 7943-7947, (Springer. DOI 10.1007/978-1-4419-0465-2_2193).Obidiegwu J E and Akpabio E M 2017 The Geography of Yam Cultivation in Southern Nigeria: Exploring Its Social Meanings and Cultural Functions J. Ethnic Foods 4 28-35.Chandrasekara A and Kumar T J 2016 Roots and Tuber Crops as Functional Foods: A Review on Phytochemical Constituents and Their Potential Health Benefits Intl. J. Food Sci. 2016 1-15.Kumar S, Das G, Shin H-S and Patra J K 2017 Dioscorea spp. (A Wild Edible Tuber): A Study on Its Ethnopharmacological Potential and Traditional Use by the Local People of Similipal Biosphere Reserve India Front. Pharmacol. 8 52.Lin J Y, Lu S, Liou Y L and Liou H L 2006a Antioxidant and Hypolipidaemic Effects of a Novel Yam–boxthorn Noodle in an In Vivo Murine Model Food Chem. 94 377–384.Lin J Y, Lu S, Liou Y L and Liou H L, 2006b, Increased IgA and IgG Serum Levels Using a Novel Yam–boxthorn Noodle in a BALB/c Mouse Model Food Chem. Toxicol. 44 170–178.Bhandari M R and Kawabata J 2004 Organic Acid, Phenolic Content and Antioxidant Activity of Wild Yam (Dioscorea spp.) Tubers of Nepal Food Chem. 88 163–168.Lin J T and Yang D J 2008 Determination of Steroidal Saponins in Different Organs of Yam (Dioscorea pseudojaponica Yamamoto) Food Chem. 108 1068–1074.AOAC 1984. Official Methods of Analysis. Washington DC: Association of Official Analytical Chemists.Harborne J B 1984 Phytochemical Method 2nd ed. (London: Chapman and Hall Ltd.)Bhandari M R, Kasai T and Kawabata J 2003 Nutritional Evaluation of Wild Yam (Dioscorea spp.) Tubers of Nepal Food Chem. 82 619–623.Adepoju O T, Boyejo O and Adeniji P O 2017 Nutrient and Antinutrient Composition of Yellow Yam (Dioscorea cayenensis) Products Data in Brief 11  428–431.Wu Z-G, Jiang W, Nitin M, Bao X-Q, Chen S-L and Tao Z-M 2016 Characterizing Diversity Based on Nutritional and Bioactive Compositions of Yam Germplasm (Dioscorea spp.) Commonly Cultivated in China J. Food Drug Anal. 24 367 – 375.Udensi E A, Osebele H O and Iweala O O 2008 The Investigation of Chemical Composition and Functional Properties of Water Yam (Dioscorea alata): Effect of Varietal Differences Pakistan J. Nutrition 7(2) 342-344.Hornick S B 1992 Factors Affecting the Nutritional Quality of Crops Am. J. Altern. Agric. 7 (Special Issue on Soil Quality) 63-68.Lewicki P P 2004 Water as the Determinant of Food Engineering Properties, A Review J. Food Eng. 61 483–495Yeh A-I, Chan T-Y and Chuang G C-C 2009 Effect of Water Content and Mucilage on Physico-chemical Characteristics of Yam (Discorea alata Purpurea) Starch J. Food Eng. 95 106–114.McPherson E and Jane J 1999 Comparison of Waxy Potato with Other Root And Tuber Starches Carbohydr. Polym. 40 57–70.Freitas R A, Paula R C, Feitosa J P A, Rocha S and Sierakowski M R 2004 Amylose Contents, Rheological Properties and Gelatinization Kinetics of Yam (Dioscorea alata) and cassava (Manihot utilissima) starches Carbohydr. Polym. 55 3–8.Barsby T L, Donald A M, Frazier P J, Donald A M, Perry P A and Waigh T A 2001 The Impact of Internal Granule Structure on Processing and Properties in Starch: Advances in Structure and Function p 45-52 (Royal Society of Chemistry, http://dx.doi.org/10.1039/9781847551917-00045)Tattiyakul J, Naksriarporn T and Pradipasena P 2012 X-ray Diffraction Pattern and Functional Properties of Dioscorea hispida Dennst Starch Hydrothermally Modified at Different Temperatures Food Bioproc. Technol. 5 964–971.Savikin-Fodulovic K, Grubisic D, Culafic L, Menkovic N and Ristic M 1998 Diosgenin and Phytosterols Content in Five Callus Lines of Dioscorea balcanica Plant Sci. 135 63–67.Cushnie T. P. T, Cushnie B and Lamb A J 2014 Alkaloids: An Overview of Their Antibacterial, Antibiotic-enhancing and Antivirulence Activities Int. J. Antimicrob. Agents 44 (5) 377-386.Tholl D 2015 Biosynthesis and Biological Functions of Terpenoids in Plants, Biotechnology of Isoprenoids p 63-106 Part of the Advances in Biochemical Engineering/Biotechnology book series (ABE, volume 148).Nagata K, Aistrup G L, Honda H, Shono T and Narahashi T 1999 Modulation of the Nicotinic Acetylcholine Receptor by Dioscorine in Clonal Rat Phaeochlomocytoma (PC12) Cells Pestic. Biochem. Physiol. 64 (3) 157–165.Bhandari M R and Kawabata J 2005 Bitterness and Toxicity in Wild Yam (Dioscorea spp.) Tubers of Nepal Plant Foods Hum. Nutr. 60 129–135, 2005.White W L B , Arias-Garzon D I, McMahon J M and Sayre R 1998 Cyanogenesis in Cassava: The Role of Hydroxynitrile Lyase in Root Cyanide Production Plant Physiol. 116 1219-25.Kumoro A C and Hartati I. 2015 Microwave Assisted Extraction of Dioscorin from Gadung (Dioscorea hispida Dennst) Tuber Flour, Procedia Chem. 14 47 – 55.
MIXED MATRIX MEMBRANE ADSORBERS FOR GLYCEROL REMOVAL IN BIODIESEL Saiful Saiful; Febrina Pratiwi; Ilham Maulana; Muliadi Ramli
Jurnal Natural Volume 12, Number 1, March 2012
Publisher : Universitas Syiah Kuala

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (688.159 KB)

Abstract

Mixed matrixmembrane (MMM) adsorbers systems function as short and wide chromatographic columns in which the adsorptive packing consists of one or more micro-porous membranes. This study reports the use of membrane adsorbers for glycerol capturing and removing in crude biodiesel. The MMM are prepared by a wet phase inversion method. Magnesol were incorporated as active sites in the membrane. Matrix support of the membrane was prepared from chitosan.The optimum compositions of the adsorptive membranes were 3 % chitosan, 15% DMF and 60% loading adsorbent. The porosity of these membranes was 34 % and swelling degree was 52 %. The membrane clean water flux was 225 Lm-2h-1 at a trans-membrane pressure of 2.5 bar. The adsorptive membrane has been demonstrated to reduce the concentration of total glycerol in crude biodiesel. The amount of glycerol in biodiesel can be reduced 69.93 % in 60 minute which is agreed to value of SNI quality standards. The membrane adsorber can be regenerated and reused for biodiesel purification. The regenerated membrane can be reused with maintaining the high adsorption capacity. The methanol was better than ethanol to regenerate the magnesol membrane. The Magnesol membrane will be a new alternative method for biodiesel purification.Mixed matrixmembrane (MMM) adsorbers systems function as short and wide chromatographic columns in which the adsorptive packing consists of one or more micro-porous membranes. This study reports the use of membrane adsorbers for glycerol capturing and removing in crude biodiesel. The MMM are prepared by a wet phase inversion method. Magnesol were incorporated as active sites in the membrane. Matrix support of the membrane was prepared from chitosan.The optimum compositions of the adsorptive membranes were 3 % chitosan, 15% DMF and 60% loading adsorbent. The porosity of these membranes was 34 % and swelling degree was 52 %. The membrane clean water flux was 225 Lm-2h-1 at a trans-membrane pressure of 2.5 bar. The adsorptive membrane has been demonstrated to reduce the concentration of total glycerol in crude biodiesel. The amount of glycerol in biodiesel can be reduced 69.93 % in 60 minute which is agreed to value of SNI quality standards. The membrane adsorber can be regenerated and reused for biodiesel purification. The regenerated membrane can be reused with maintaining the high adsorption capacity. The methanol was better than ethanol to regenerate the magnesol membrane. The Magnesol membrane will be a new alternative method for biodiesel purification.
PENENTUAN WAKTU MATI MEMANFAATKAN DERET HOMOLOG ALKILPARABEN PADA RP-HPLC DALAM SISTEM PELARUT METANOL/AIR Mahmudi .; Saiful .; Khairan .; Rinaldi Idroes
Jurnal Natural Volume 15, Number 2, September 2015
Publisher : Universitas Syiah Kuala

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (203.052 KB)

Abstract

Penelitian ini dalam rangka pengembangan dan aplikasi metode penentuan waktu mati (t0) pada Kromatografi Cair dari yang telah pernah dan berhasil diterapkan di GC. Waktu mati merupakan parameter yang sangat penting untuk penentuan parameter lain seperti Faktor kapasitas (k’), retensi relative (tR’) dan indeks retensi kovats (IR), sehingga didapat hasil berupa data base yang bisa diterapkan dalam intrumentasi GC dan RP-HPLC. Penentuan waktu mati dengan menggunakan dua metode yaitu metode iterasi dan metode linearisasi, sehingga didapat nilai indeks retensi kovats dari senyawa uji pada sistem RP-HPLC dengan menggunakan deret homolog alkilparaben. Hasil penelitian menunjukkan deret homolog alkilparaban terbukti dapat digunakan untuk penentuan indeks retensi Kovats  dalam RP-HPLC dengan koefisien korelasi yang sangat baik  terutama pada sistem pelarut MeHO/H2O (90:10). 
PURIFICATION OF BIODIESEL USING RICE STRAW AND DIOSCOREA ALATA STARCH AS NATURAL ADSORBENTS Yulidar Yulidar; Saiful Saiful; Ilham Maulana
Jurnal Natural Volume 19, Number 1, February 2019
Publisher : Universitas Syiah Kuala

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (420.31 KB) | DOI: 10.24815/jn.v19i1.12452

Abstract

Janeng starch (Dioscorea Alata) and rice straws are developed to be used as adsorbents in dry washing method to purify crude biodiesel. In this study, we evaluate the potential of rice straw and janeng starch as natural adsorbents in the purification of biodiesel that replace the role of water in absorbing contaminants from biodiesel. The SEM characterization results show that the starch adsorbent and rice straw has an open and porous surface and is evenly distributed for janeng starch. Both adsorbents, either the janeng starch or rice straw, can be applied for the purification of biodiesel. The quality of biodiesel is influenced by the amount of adsorbents used in biodiesel purification. The effectiveness of the adsorbent is shown by the decrease in free fatty acids, alkali numbers, soap numbers and turbidity levels in biodiesel. The concentration of free fatty acid oil in crude biodiesel before the purification step was 0.769 mg-KOH/g, then decreased to 0.128 mg-KOH/g after the adsorption. This acid value had been very low and met the Indonesian quality national standard for biodiesel spesically 0.50 mg-KOH/g. Either janeng starch or rice straw adsorbent was able to reduce the soap content of potassium oleate to level 53.33 ppm from the initial content of 106.67 ppm. These two natural adsorbents can be the alternative adsorbents in the purification of biodiesel that employs dry washing method.
PREPARATION OF INORGANIC CATALYST BASED HEMATITE (a-Fe2O3) COMPOUND EXTRACTED FROM ACEH IRON ORE MINERAL AND ITS CATALYTIC ACTIVITY ON TRANSESTERIFICATION OF COCONUT OIL Muliadi Ramli; Anneza Astriet; T. Banta Darmawan; Saiful Saiful; Susilawati Susilawati; Nasrullah Idris
Jurnal Natural Volume 19, Number 1, February 2019
Publisher : Universitas Syiah Kuala

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (289.745 KB) | DOI: 10.24815/jn.v19i1.12855

Abstract

Hematite (Fe2O3) was successfully extracted from the Aceh iron ore mineral by precipitation method with employing sulphuricacid (H2SO4) as chemical agent.  Furthermore, the extracted hematite was modified with sodium metal (K), namely it doped with NaOH of 5% and 10% (w/w), respectively. Based on the characterization results using XRD and SEM- EDS proved that modified catalyst (Na2O/Fe2O3) with their homogeneous size were resulted while the hematite (Fe2O3) particles was dopped withNaOH at its low concentration of (5% wt/wt), however while doping with the higher concentration of NaOH (10% w/w), agglomeration was taken place among the catalyst particles in which decreasing the surface area of the modified catalysts. Finally, the modified catalyst (Na2O/Fe2O3) was successfully applied as an inorganic catalyst on transesterification of coconut oil and methanol (T = 55 – 60oC, 2 h)for forming methyl esters asbiodiesel compounds. 
PREPARATION OF INORGANIC CATALYST BASED HEMATITE (a-Fe2O3) COMPOUND EXTRACTED FROM ACEH IRON ORE MINERAL AND ITS CATALYTIC ACTIVITY ON TRANSESTERIFICATION OF COCONUT OIL Muliadi Ramli; Anneza Astriet; T. Banta Darmawan; Saiful Saiful; Susilawati Susilawati; Nasrullah Idris
Jurnal Natural Volume 19, Number 1, February 2019
Publisher : Universitas Syiah Kuala

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24815/jn.v19i1.12855

Abstract

Hematite (Fe2O3) was successfully extracted from the Aceh iron ore mineral by precipitation method with employing sulphuricacid (H2SO4) as chemical agent.  Furthermore, the extracted hematite was modified with sodium metal (K), namely it doped with NaOH of 5% and 10% (w/w), respectively. Based on the characterization results using XRD and SEM- EDS proved that modified catalyst (Na2O/Fe2O3) with their homogeneous size were resulted while the hematite (Fe2O3) particles was dopped withNaOH at its low concentration of (5% wt/wt), however while doping with the higher concentration of NaOH (10% w/w), agglomeration was taken place among the catalyst particles in which decreasing the surface area of the modified catalysts. Finally, the modified catalyst (Na2O/Fe2O3) was successfully applied as an inorganic catalyst on transesterification of coconut oil and methanol (T = 55 – 60oC, 2 h)for forming methyl esters asbiodiesel compounds. 
NUTRITIONAL COMPOSITION OF DIOSCOREA HISPIDA FROM DIFFERENT LOCATIONS AROUND LEUSER ECOSYSTEM AREA Sitti Saleha; Nurdin Saidi; Saiful .; Murniana .; Saida Rasnovi; Teuku M. Iqbalsyah
Jurnal Natural Volume 18, Number 1, February 2018
Publisher : Universitas Syiah Kuala

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24815/jn.v18i1.8504

Abstract

Proximate analysis of Dioscorea hispida tubers, collected from five locations around Leuser ecosystem in Aceh Province, showed variations amongst samples. Standard AOAC method for proximate analysis of the fresh weight showed that the water content varied between 15.8 - 37.8%, crude protein 1.13 -6.20%, crude lipid 1.99 - 9.36% and ash 0.29 - 1.24%. The total carbohydrate was high, i.e. between 58.3 -71.9%. The main mineral was phosphorus, with a value of 11.7 - 46.9 mg/100g. These variations could be due to soil, climate and weather factors, as well as postharvest handling. Phytochemical tests showed that all of the samples contained alkaloids and terpenoids. One of the samples (LP) also contained phenol and steroid. The high cyanide content in the tubers (379 - 739 ppm) was easily removed by repeated washing. The cyanide level dropped significantly after the 3rd wash. Information on nutritional content in D. hispida is essential for planning its utilization. Increasing the economic value of D. hispida is expected to attract people around the Leuser ecosystem to cultivate and utilize it, thereby reducing illegal forest encroachment.Keywords: Dioscorea hispida, proximate, Leuser, janeng, gadung, starchREFERENCESBarton H 2014 Yams: Origins and Development, Encyclopaedia of Global Archaeology, p 7943-7947, (Springer. DOI 10.1007/978-1-4419-0465-2_2193).Obidiegwu J E and Akpabio E M 2017 The Geography of Yam Cultivation in Southern Nigeria: Exploring Its Social Meanings and Cultural Functions J. Ethnic Foods 4 28-35.Chandrasekara A and Kumar T J 2016 Roots and Tuber Crops as Functional Foods: A Review on Phytochemical Constituents and Their Potential Health Benefits Intl. J. Food Sci. 2016 1-15.Kumar S, Das G, Shin H-S and Patra J K 2017 Dioscorea spp. (A Wild Edible Tuber): A Study on Its Ethnopharmacological Potential and Traditional Use by the Local People of Similipal Biosphere Reserve India Front. Pharmacol. 8 52.Lin J Y, Lu S, Liou Y L and Liou H L 2006a Antioxidant and Hypolipidaemic Effects of a Novel Yam–boxthorn Noodle in an In Vivo Murine Model Food Chem. 94 377–384.Lin J Y, Lu S, Liou Y L and Liou H L, 2006b, Increased IgA and IgG Serum Levels Using a Novel Yam–boxthorn Noodle in a BALB/c Mouse Model Food Chem. Toxicol. 44 170–178.Bhandari M R and Kawabata J 2004 Organic Acid, Phenolic Content and Antioxidant Activity of Wild Yam (Dioscorea spp.) Tubers of Nepal Food Chem. 88 163–168.Lin J T and Yang D J 2008 Determination of Steroidal Saponins in Different Organs of Yam (Dioscorea pseudojaponica Yamamoto) Food Chem. 108 1068–1074.AOAC 1984. Official Methods of Analysis. Washington DC: Association of Official Analytical Chemists.Harborne J B 1984 Phytochemical Method 2nd ed. (London: Chapman and Hall Ltd.)Bhandari M R, Kasai T and Kawabata J 2003 Nutritional Evaluation of Wild Yam (Dioscorea spp.) Tubers of Nepal Food Chem. 82 619–623.Adepoju O T, Boyejo O and Adeniji P O 2017 Nutrient and Antinutrient Composition of Yellow Yam (Dioscorea cayenensis) Products Data in Brief 11  428–431.Wu Z-G, Jiang W, Nitin M, Bao X-Q, Chen S-L and Tao Z-M 2016 Characterizing Diversity Based on Nutritional and Bioactive Compositions of Yam Germplasm (Dioscorea spp.) Commonly Cultivated in China J. Food Drug Anal. 24 367 – 375.Udensi E A, Osebele H O and Iweala O O 2008 The Investigation of Chemical Composition and Functional Properties of Water Yam (Dioscorea alata): Effect of Varietal Differences Pakistan J. Nutrition 7(2) 342-344.Hornick S B 1992 Factors Affecting the Nutritional Quality of Crops Am. J. Altern. Agric. 7 (Special Issue on Soil Quality) 63-68.Lewicki P P 2004 Water as the Determinant of Food Engineering Properties, A Review J. Food Eng. 61 483–495Yeh A-I, Chan T-Y and Chuang G C-C 2009 Effect of Water Content and Mucilage on Physico-chemical Characteristics of Yam (Discorea alata Purpurea) Starch J. Food Eng. 95 106–114.McPherson E and Jane J 1999 Comparison of Waxy Potato with Other Root And Tuber Starches Carbohydr. Polym. 40 57–70.Freitas R A, Paula R C, Feitosa J P A, Rocha S and Sierakowski M R 2004 Amylose Contents, Rheological Properties and Gelatinization Kinetics of Yam (Dioscorea alata) and cassava (Manihot utilissima) starches Carbohydr. Polym. 55 3–8.Barsby T L, Donald A M, Frazier P J, Donald A M, Perry P A and Waigh T A 2001 The Impact of Internal Granule Structure on Processing and Properties in Starch: Advances in Structure and Function p 45-52 (Royal Society of Chemistry, http://dx.doi.org/10.1039/9781847551917-00045)Tattiyakul J, Naksriarporn T and Pradipasena P 2012 X-ray Diffraction Pattern and Functional Properties of Dioscorea hispida Dennst Starch Hydrothermally Modified at Different Temperatures Food Bioproc. Technol. 5 964–971.Savikin-Fodulovic K, Grubisic D, Culafic L, Menkovic N and Ristic M 1998 Diosgenin and Phytosterols Content in Five Callus Lines of Dioscorea balcanica Plant Sci. 135 63–67.Cushnie T. P. T, Cushnie B and Lamb A J 2014 Alkaloids: An Overview of Their Antibacterial, Antibiotic-enhancing and Antivirulence Activities Int. J. Antimicrob. Agents 44 (5) 377-386.Tholl D 2015 Biosynthesis and Biological Functions of Terpenoids in Plants, Biotechnology of Isoprenoids p 63-106 Part of the Advances in Biochemical Engineering/Biotechnology book series (ABE, volume 148).Nagata K, Aistrup G L, Honda H, Shono T and Narahashi T 1999 Modulation of the Nicotinic Acetylcholine Receptor by Dioscorine in Clonal Rat Phaeochlomocytoma (PC12) Cells Pestic. Biochem. Physiol. 64 (3) 157–165.Bhandari M R and Kawabata J 2005 Bitterness and Toxicity in Wild Yam (Dioscorea spp.) Tubers of Nepal Plant Foods Hum. Nutr. 60 129–135, 2005.White W L B , Arias-Garzon D I, McMahon J M and Sayre R 1998 Cyanogenesis in Cassava: The Role of Hydroxynitrile Lyase in Root Cyanide Production Plant Physiol. 116 1219-25.Kumoro A C and Hartati I. 2015 Microwave Assisted Extraction of Dioscorin from Gadung (Dioscorea hispida Dennst) Tuber Flour, Procedia Chem. 14 47 – 55.
PURIFICATION OF BIODIESEL USING RICE STRAW AND DIOSCOREA ALATA STARCH AS NATURAL ADSORBENTS Yulidar Yulidar; Saiful Saiful; Ilham Maulana
Jurnal Natural Volume 19, Number 1, February 2019
Publisher : Universitas Syiah Kuala

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24815/jn.v19i1.12452

Abstract

Janeng starch (Dioscorea Alata) and rice straws are developed to be used as adsorbents in dry washing method to purify crude biodiesel. In this study, we evaluate the potential of rice straw and janeng starch as natural adsorbents in the purification of biodiesel that replace the role of water in absorbing contaminants from biodiesel. The SEM characterization results show that the starch adsorbent and rice straw has an open and porous surface and is evenly distributed for janeng starch. Both adsorbents, either the janeng starch or rice straw, can be applied for the purification of biodiesel. The quality of biodiesel is influenced by the amount of adsorbents used in biodiesel purification. The effectiveness of the adsorbent is shown by the decrease in free fatty acids, alkali numbers, soap numbers and turbidity levels in biodiesel. The concentration of free fatty acid oil in crude biodiesel before the purification step was 0.769 mg-KOH/g, then decreased to 0.128 mg-KOH/g after the adsorption. This acid value had been very low and met the Indonesian quality national standard for biodiesel spesically 0.50 mg-KOH/g. Either janeng starch or rice straw adsorbent was able to reduce the soap content of potassium oleate to level 53.33 ppm from the initial content of 106.67 ppm. These two natural adsorbents can be the alternative adsorbents in the purification of biodiesel that employs dry washing method.