Ponding system or land application techniques are widely used at industrial scale to treat palm oil mill effluent (POME) prior to discharge to the environment. POME is considered as one of the major problems that has generated voluminously from the palm oil industries. The main purpose of this article is to organize the scattered available information on various aspects and a wide range of promising current POME treatments including biological microorganisms, physicochemical methods of coagulation, and membrane and thermochemical process. In addition, the integrated system of anaerobic-aerobic bioreactor (IAAB), which has been touted as highly efficient with easy control at acceptable temperature range and shorter treatment time, has potential to be exploited for POME treatment. The main influencing factors for IAAB POME treatment are highlighted as outstanding characteristics for challenges and future prospects.

Tons of anthropological activities contribute daily to the massive amount of lignocellulosic wastes produced annually. Unfortunately, their full potential usually is underutilized, and most of the biomass ends up in landfills. Lignocellulolytic enzymes are vital and central to developing an economical, environmentally friendly, and sustainable biological method for pre-treatment and degradation of lignocellulosic biomass which can lead to the release of essential end products such as enzymes, organic acids, chemicals, feed, and biofuel. Sustainable degradation of lignocellulosic biomass via hydrolysis is achievable by lignocellulolytic enzymes, which can be used in various applications, including but not limited to biofuel production, the textile industry, waste treatment, the food and drink industry, personal care industry, health and pharmaceutical industries. Nevertheless, for this to materialize, feasible steps to overcome the high cost of pre-treatment and lower operational costs such as handling, storage, and transportation of lignocellulose waste need to be deployed. Insight on lignocellulolytic enzymes and how they can be exploited industrially will help develop novel processes that will reduce cost and improve the adoption of biomass, which is more advantageous. This review focuses on lignocellulases, their use in the sustainable conversion of waste biomass to produce valued-end products, and challenges impeding their adoption.

Discovering novel bacterial strains might be the link to unlocking the value in lignocellulosic bio-refinery as we strive to find alternative and cleaner sources of energy. Bacteria display promise in lignocellulolytic breakdown because of their innate ability to adapt and grow under both optimum and extreme conditions. This versatility of bacterial strains is being harnessed, with qualities like adapting to various temperature, aero tolerance, and nutrient availability driving the use of bacteria in bio-refinery studies. Their flexible nature holds exciting promise in biotechnology, but despite recent pointers to a greener edge in the pretreatment of lignocellulose biomass and lignocellulose-driven bioconversion to value-added products, the cost of adoption and subsequent scaling up industrially still pose challenges to their adoption. However, recent studies have seen the use of co-culture, co-digestion, and bioengineering to overcome identified setbacks to using bacterial strains to breakdown lignocellulose into its major polymers and then to useful products ranging from ethanol, enzymes, biodiesel, bioflocculants, and many others. In this review, research on bacteria involved in lignocellulose breakdown is reviewed and summarized to provide background for further research. Future perspectives are explored as bacteria have a role to play in the adoption of greener energy alternatives using lignocellulosic biomass.