_Applied_  
_sciences_  
_Article_  
**Zero-Emission of Palm Oil Mill Effluent Final Discharge**  
**Promoted Bacterial Biodiversity**  
**Water System**  
**[PERSON] 1, [PERSON] 1,2,*\(\copyright\), [PERSON] 1, [PERSON] 1, [PERSON] 3, [PERSON] 1,4 and [PERSON] 3**  
Department of Bioprocess Technology, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, Seri Kembangan 43400, Selangor, Malaysia; [EMAIL_ADDRESS] (N.S.L.M.-Z. ); [EMAIL_ADDRESS] (N.Z. ); [EMAIL_ADDRESS] (N.A.J. ); [EMAIL_ADDRESS] (M.A.H.) Laboratory of Biopolymer and Derivatives, Institute of Tropical Forestry and Forest Products (INTRROP), Universiti Putra Malaysia, Seri Kembangan 43400, Selangor, Malaysia  
Department of Biological Functions Engineering, Graduate School of Life Science and Systems Engineering, Kyushu Institute of Technology, 2-4 Hibikino, Wakamatsu-ku, Fukuoka 808-0196, Japan; [EMAIL_ADDRESS] (N.A.M. ); [EMAIL_ADDRESS] (T.M.) Processing and Product Development Laboratory, Institute of Plantation Studies, Universiti Putra Malaysia, Seri Kembangan 43400, Selangor, Malaysia  
Correspondence: [EMAIL_ADDRESS]; Tel. :+60-397691948  
**Citation:** [PERSON]; [PERSON]; [PERSON] [PERSON]; [PERSON] [PERSON]; [PERSON] [PERSON]; [PERSON]; [PERSON] [PERSON] Zero-Emission of Palm Oil Mill Effluent Final Discharge**  
Wolf Ellluent Final Discharge**  
Promoted Bacterial Biodiversity**  
Rebound in the Receiving Water  
[[https://doi.org/10.3390/app112210814](https://doi.org/10.3390/app112210814)]([https://doi.org/10.3390/app112210814](https://doi.org/10.3390/app112210814))  
Academic Editors: [PERSON] and [PERSON]  
Received: 26 September 2021  
Accepted: 28 October 2021  
Published: 16 November 2021  
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published maps and institutional affiliations. the biomass such as palm kernel shells, mesocarp fibers and empty fruit bunches, as well as the liquid waste known as palm oil mill effluent (POME) have caused environmental casualties [1]. Since POME is the most abundant waste produced from the production of palm oil, it has gained serious attention from researchers and industries who wish to resolve the pollution issues caused by its discharge. The zero-emission system of POME is defined as an integrated system with no net waste discharge into the environment from the mill and a system that can implement the sustainable and integrated palm oil biorefinery concept [2]. This is a continuous effort that aims to treat the incoming effluents by completely utilizing the waste into something useful [3], such as for the production of biogas and biofertilizer [4] and as recycled water for the processing of palm oil [5]. With the aim to fulfil this goal, the researchers in [3,4] proposed a flow diagram of the treatment process of zero-emission of POME where all of the wastes, including solids, liquids, and gases were recycled for the mill's operation (Figure 1). This system leads to a more sustainable and environmentally friendly production of palm oil [6] while reducing the cost for waste treatment and the operation of the mill [7]. In addition, the more stringent environmental regulations have become the driving force for palm oil mills to intensely improve their waste management system to achieve better sustainability in palm oil production and in the hope of reducing health issues to humans and the environment [8]. The application of the zero-emission system has a positive impact on a receiving waterway that has been previously exposed to the pollution. The reduced intake of polluting properties, such as biological oxygen demand (BOD), chemical oxygen demand (COD), total suspended solid (TSS), and nutrient content positively affects the aquatic ecosystem [9]. Microorganisms are among the living organisms in the receiving waterway that are affected due to the introduction of wastewater [10]. A previous study reported on the reduction in the fecal coliform following the implementation of zero-emission of municipal wastewater [11].