Microbiota of Palm Oil Mill Wastewater in Malaysia

Abstract

This study was aimed at identifying indigenous microorganisms from palm oil mill effluent (POME) and to ascertain the microbial load. Isolation and identification of indigenous microorganisms was subjected to standard microbiological methods and sequencing of the 16S rRNA and 18S rRNA genes. Sequencing of the 16S rRNA and 18S rRNA genes for the microbial strains signifies that they were known as Micrococcus luteus 101PB, Stenotrophomonas maltophilia 102PB, Bacillus cereus 103PB, Providencia vermicola 104PB, Klebsiella pneumoniae 105PB, Bacillus subtilis 106PB, Aspergillus fumigatus 107PF, Aspergillus nomius 108PF, Aspergillus niger 109PF and Meyerozyma guilliermondii 110PF. Results revealed that the population of total heterotrophic bacteria (THB) ranged from 9.5 × 105 – 7.9 × 106 cfu/mL. The total heterotrophic fungi (THF) ranged from 2.1 × 104 – 6.4 × 104 cfu/mL. Total viable heterotrophic indigenous microbial population on CMC agar ranged from 8.2 × 105 – 9.1 × 106 cfu/mL and 1.4 × 103 – 3.4 × 103 cfu/mL for bacteria and fungi respectively. The microbial population of oil degrading bacteria (ODB) ranged from 6.4 × 105 – 4.8 × 106 cfu/mL and the oil degrading fungi (ODF) ranged from 2.8 × 103 – 4.7 × 104 cfu/mL. The findings revealed that microorganisms flourish well in POME. Therefore, this denotes that isolating native microorganisms from POME is imperative for effectual bioremediation, biotreatment and biodegradation of industrial wastewaters.

Evaluation Ability of Different Barada River Micrococcus Spp. Strain to Bioremediation of Hydrocarbons

“…In general, the ability of biodegradation was decreased with concentration increasing, as shown in Figure 3, which is compatible with results of Tazeena and his team in 2013, and this is expected because crude oil contains many toxic compounds [2,40,41], that pose a real hazard on all organisms, especially decomposers in water. When crude oil exists in high concentration means increase in insoluble substances, and increase in concentration heavy metals, all this has adverse effects on bioremediation of hydrocarbons [4,23,30,42]. Results showed raise on TVC values with a raise in incubation period until the 12 th day, which agrees with [3,43].…”

“…Hydrocarbons pollution is one of the most significant contamination problems on the continent because it contains a lot of toxic compounds, which have a toxic effect on all organisms, especially in aquatic environments, as well as their ability to increase values biochemical oxygen demand (BOD), chemical oxygen demand (COD) and total suspended solid (TTS), in addition to the petroleum contaminated water contains hazardous materials such as aromatic hydrocarbons and polycyclic aromatic hydrocarbons and they are potentially toxic, mutagenic and carcinogenic, and they are fixed in the environment, so they are dangerous if not controlled [1][2][3][4][5][6]. Remediation of oil-contaminated system could be achieved by either physicochemical or biological methods.…”

Identification and cultivation of hydrogenotrophic methanogens from palm oil mill effluent for high methane production

“…A wide variety of microorganisms existing symbiotically in POME have been previously reported, while most of the hydrolytic and fermentative bacteria in POME belong to the phyla Firmicutes, Bacteroidetes, Actinobacteria, and Proteobacteria along with species in the genera like Clostridium, Bacillus, Pseudomonas, Micrococcus, Lactobacillus, Syntrophomonas, Stenotrophomonas, and Enterobacter. [7][8][9][10] While after biogas production, methanogens have been found in the treated POME lagoon, and they were reported to be from the genera Methanobacterium, Methanosarcina, Methanospirillum, Methanocaldococcus, and Methanosaeta of the phylum Euryarchaeota, which are methaneproducing archaea. [7][8][9][10] Among the participating microbes in AD, methanogens grow slowest and are highly sensitive to environmental changes.…”

“…[7][8][9][10] While after biogas production, methanogens have been found in the treated POME lagoon, and they were reported to be from the genera Methanobacterium, Methanosarcina, Methanospirillum, Methanocaldococcus, and Methanosaeta of the phylum Euryarchaeota, which are methaneproducing archaea. [7][8][9][10] Among the participating microbes in AD, methanogens grow slowest and are highly sensitive to environmental changes. But their growth and activity are crucial for biogas production because they are directly responsible for methane conversion in the final stage of methanogenesis.…”

“…7,13 The mcrA gene encoding a subunit of methyl-coenzyme M reductase, the key enzyme in the methane production pathway, has been used as an alternative or in parallel with 16S rRNA gene to identify methanogens due to its exclusive occurrence in these organisms. [8][9][10]14 Therefore, the understanding of bacterial and archaeal communities' composition in the POME treatment system and their metabolic link to methanogenesis should lead to a guideline for the improvement of biogas production efficiency. Previous studies showed that inoculation of either single methanogen or a consortium could improve AD treatments and biogas production.…”