Cover Image, Volume 92, Issue 5Ali, Manal; Farghaly, Ahmed; Roux, Sophie Le; Peu, Pascal; Dabert, Patrick; Tawfik, Ahmed
doi: 10.1002/jctb.5264pmid: N/A
The cover image, by Manal Ali et al., is based on the Research Article Potential of using non‐inoculated self‐aerated immobilized biomass reactor for post‐treatment of upflow anaerobic staged reactor treating high strength industrial wastewater, DOI: 10.1002/jctb.5082.
Perspectives on the utilization of waste fat from beef cattle and fowl for biodiesel production in MexicoChavarria‐Hernandez, Juan; Ordóñez, Luis; Barahona‐Pérez, Luis Felipe; Castro‐Gomez, Marisol; Paredes‐Cervantes, Samantha
doi: 10.1002/jctb.5057pmid: N/A
The purpose of this research was to perform a preliminary inventory of the waste fat generated from beef cattle and fowl in Mexico that could be used for biodiesel production. Additionally, the CO2 emissions reduction that could be achieved by using the potential biodiesel to replace an energy‐equivalent amount of fossil diesel was assessed. Based on national reports for the year 2014, it was estimated that the non‐edible fat from beef cattle and fowl annually generated in Mexico is sufficient to produce 216.0 kt of biodiesel, which would furnish 8379 TJ. This amount is equivalent to 1.5% of the energy annually consumed in Mexico as fossil diesel for road transport. The potential 216.0 kt of animal fat‐based biodiesel that can be produced annually could replace 198.3 kt of fossil diesel and thus allow a reduction in the WTW (well to wheels) emissions of 592.3 kt CO2, which represents 1.5% of the WTW CO2 emitted from the combustion of the fossil diesel used for road transportation in Mexico in the year 2014. © 2016 Society of Chemical Industry
An overview of the enzyme potential in bioenergy‐producing biorefineriesEscamilla‐Alvarado, Carlos; Pérez‐Pimienta, José A; Ponce‐Noyola, Teresa; Poggi‐Varaldo, Héctor M
doi: 10.1002/jctb.5088pmid: N/A
Biorefineries are considered as an integrative thinking that focuses on the possibility of obtaining as many added‐value products as technically and economically feasible. However, in practice most biorefineries comprise only enzymatic or chemical pretreatment followed by biofuel generation. The drop in oil prices may menace the development of this young industry, as has happened before in history. This has become a fundamental reason for which the biofuel industry should not consider only biofuels production, but enzyme and non‐fuel based chemicals as well. Hence, this work aims at overviewing the most important enzymes involved in biotechnological processes and to describe their role in biorefineries. Bioethanol, biogas and biodiesel biorefineries are overviewed, along with the integrated and industrial types. Finally separation and purification processes in biorefineries are discussed. © 2016 Society of Chemical Industry
Heterotrophic cultivation of microalgae: production of metabolites of commercial interestMorales‐Sánchez, Daniela; Martinez‐Rodriguez, Oscar A; Martinez, Alfredo
doi: 10.1002/jctb.5115pmid: N/A
Several microalgal species are capable of growing heterotrophically, exhibiting considerable metabolic versatility and flexibility. As demonstrated in this review, heterotrophic conditions can enhance the biomass concentration by as much as 25‐fold compared with phototrophic conditions. Currently, these types of cultivation are economically feasible only for high‐value products, including polyunsaturated fatty acids (PUFAs), pigments, antioxidants, polysaccharides, food and aquaculture feed from carbon sources, such as glucose, acetate or glycerol. To make heterotrophic cultivation economically viable for high‐volume, low‐value commodities, such as biofuels, the use of unconventional carbon sources, such as food and agricultural wastes and wastewater, is recommended. Since microalgae are capable of modifying their metabolism according to varying culture conditions, it is possible to modify, control and therefore maximize the production of target compounds. This manuscript not only offers a review of the most relevant and recent findings in the use of heterotrophic microalgal cultivation for enhanced metabolite production but also provides recommendations for future research on this promising subject. © 2016 Society of Chemical Industry
A review of the potential of pretreated solids to improve gas biofuels production in the context of an OFMSW biorefineryRomero‐Cedillo, Leticia; Poggi‐Varaldo, Hector M; Ponce‐Noyola, Teresa; Ríos‐Leal, Elvira; Ramos‐Valdivia, Ana C; Cerda‐García Rojas, Carlos M; Tapia‐Ramírez, José
doi: 10.1002/jctb.5116pmid: N/A
The organic fraction of municipal solid waste (OFMSW), mainly composed of lignocellulosic polymers, is extremely complex. Therefore, it is necessary to apply pretreatments to remove the lignin content and decrease the cellulose crystallinity in order to use the OFMSW for gas biofuels production in the context of biorefineries from waste. This work focused on critically reviewing the conventional pretreatments applied to OFMSW, with the goal of improving the H2 production, as well as other biofuels in modern biorefineries. There are a wide variety of pretreatments that have successfully been used, mainly alkaline, milling and dilute acid. In addition, some research has focused on the recovery and reutilization of the alkali, acid or solvents after the pretreatment, to be incorporated into new cycles of production, minimizing the environmental impacts. Moreover, it would be necessary to incorporate analytical tools, in order to determine the sustainability of the biorefinery project. It is concluded that waste pretreatments could significantly contribute to increased yields of biogas fuels in organic waste‐based biorefineries. Therefore, establishing preliminary stages for conditioning biomass or wastes is essential to improve the degradation of wastes and bio‐product generation. © 2016 Society of Chemical Industry