| Summary: | Palm Oil Mill Effluent (POME) is a liquid waste of palm oil industry that it
used as a growth substrate for microbial especially hydrolytic fungi and
oleaginous yeasts because it were contains very high proteins and carbohydrates.
The objective of this study was to utilize POME as a growth substrate for fungi
hydrolytic and oleaginous yeasts to produce biodiesel. The isolates were fungi
hydrolytic (strains ATH 2107, ATH 2147, ATH 2151 F2 and F1 2148 ATH) and
oleaginous yeasts, Candida sp. (strain Y09GS34 and strain Y09GS48), Lipomyces
sp. (strain Y09GS38), respectively collected from the Indonesia Institute of
Science Selection. The first step of research was purification isolates through
single cell culture (streak) technique using Potato Dextrose Agar (PDA) to fungi
and Yeast Potato Agar (YPD) to yeast. Fungi isolates were selected based on their
ability of growing on carboxymethyl cellulose (CMC) broth medium. At an
interval of time, the growth was monitored spectrophotometrically (λ=600nm),
measured based on the reducing sugars and crude cellulase activity. Isolate
showing the highest cellulolytic activity was chosen for its ability to grow on
POME. Yeast isolates were selected based on their ability to grow on different
broth medium CMC and with or without limited N (1% CMC and 2% CMC-N
limited), in order to their ability on accumulating lipid in the yeast cells. Yeast
isolate having the highest lipid accumulation in the cells was selected and lipid
components detected by Gas Chromatography Mass Spectrometry (GC-MS).
Each selected fungi and yeast were grown separately and together as a mixed
culture in fermentors, incubated at room temperature for 15 days. At an interval of
time, their growth was measured based on the change of pH, reducing sugars, dry
weight cell, and total lipid. Lipid used as feedstock to produce biodiesel. Biodiesel
produced was proven by fire tests based on its length and color flame. Selected
fungi identified by molecular analysis (phenetic). The results of the research
showed that strain fungi of ATH 2147 was demonstrate highest hydrolytic
capability. The strain yeast of Y09GS34 had the highest lipid accumulation up to
63,75% per dry weight cell grown on 2% CMC-N limited and lipid composition
consisted of palmitate acid, stearate acid, linolenate acid, and oleate acid. Mixed
cultures produced highest lipid accumulation up to 88,724% per dry weight cell
and biodiesel produced of length of flame up to 247 seconds with bluish red color.
The results of the molecular identification, the strain fungi of ATH 2147 having
characters similar to Flavodon flavus as lignocellulolytic. It could be concluded
that POME were an alternative substrate for the growth of Flavodon flavus strain
ATH 2147 and Candida sp. strain Y09GS34 to produced biodiesel.
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