Global status of lignocellulosic biorefinery: Challenges and perspectives.

Global status of lignocellulosic biorefinery: Challenges and perspectives

Fossil depletion is facing critical crisis due to its depletion reserves and increased environmental problems. The utilization of petroleum products by the dense population, urbanization of various geographical areas and industrialization has extremely affected the global economy. Fuels of biological origin such as ethanol, vegetable oil and various biomasses are gaining attention It is therefore important to develop alternative fuels in order to protect the global environment and also to focus on long-term supplies of conventional fuels. These biofuels have greater opportunity to promote agro-industrial development and productivity in large scale. Thus, it is necessary to improvise technology and develop resource sustainability focussing into the appropriate policies, production costing, yield, purity and efficiency creating health, wealth and benefit sharing to achieve a sustainable energy in future. The present review article focuses on the recent trends and researches carried out in liquid biofuel production and economy holding its future demand and utilization world-wide.

Trends and perspectives of liquid biofuel – Process and industrial viability

The Microrchidia (MORC) family proteins are important nuclear regulators in both animals and plants with critical roles in epigenetic gene silencing and genome stabilization. In the crop plant barley (Hordeum vulgare), seven MORC gene family members have been described. While barley HvMORC1 has been functionally characterized, very little information is available about other HvMORC paralogs. In this study, we elucidate the role of HvMORC6a and its potential interactors in regulating plant immunity via analysis of CRISPR/SpCas9-mediated single and double knockout (dKO) mutants, hvmorc1 (previously generated and characterized by our group), hvmorc6a, and hvmorc1/6a. For generation of hvmorc1/6a, we utilized two different strategies: (i) successive Agrobacterium-mediated transformation of homozygous single mutants, hvmorc1 and hvmorc6a, with the respective second construct, and (ii) simultaneous transformation with both hvmorc1 and hvmorc6a CRISPR/SpCas9 constructs. Total mutation efficiency in transformed homozygous single mutants ranged from 80 to 90%, while upon simultaneous transformation, SpCas9-induced mutation in both HvMORC1 and HvMORC6a genes was observed in 58% of T0 plants. Subsequent infection assays showed that HvMORC6a covers a key role in resistance to biotrophic (Blumeria graminis) and necrotrophic (Fusarium graminearum) plant pathogenic fungi, where the dKO hvmorc1/6a showed the strongest resistant phenotype. Consistent with this, the dKO showed highest levels of basal PR gene expression and derepression of TEs. Finally, we demonstrate that HvMORC1 and HvMORC6a form distinct nucleocytoplasmic homo-/heteromers with other HvMORCs and interact with components of the RNA-directed DNA methylation (RdDM) pathway, further substantiating that MORC proteins are involved in the regulation of TEs in barley.

CRISPR/SpCas9-mediated double knockout of barley Microrchidia MORC1 and MORC6a reveals their strong involvement in plant immunity, transcriptional gene silencing and plant growth.

Biomass pre-treatment techniques for the production of biofuels using thermal conversion methods – A review

Lignocellulosic biofuel has been globally recognized as a renewable energy source with environmental benefits while minimizing the competition between food and fuel supply. Although lignocellulose is a promising renewable feedstock for the sustainable production of transportation fuels, cost-effective conversion technologies are necessary to overcome its inherent recalcitrance that impedes the widespread utilization of lignocellulosic biofuels. Owing to the limited availability of cost-effective and less recalcitrant biomass, the major challenge toward biofuel commercialization includes the biochemical and genetic modification of lignocellulose in energy crops. The development of robust microbial conversion systems capable of converting a broad spectrum of carbon sources derived from biomass feedstocks into a variety of biofuels such as bioethanol, biodiesel, and advanced drop-in biofuels is also of interest in the field of biorefinery. To date, metabolic engineering and synthetic biology have made significant advances in improving the biofuel yield in feedstocks and microbial engineering. The objective of this review is to discuss the technological advances in engineering lignocellulosic biomass as an economically attractive feedstock and robust microbial platforms as a powerful biofuel producer. Finally, integrating engineering strategies and efforts in plant and microbial engineering provides future directions of an interdisciplinary approach to facilitate the commercialization of economically feasible lignocellulosic biofuels.

Recent advances and future directions in plant and yeast engineering to improve lignocellulosic biofuel production

https://onlinelibrary.wiley.com/doi/pdf/10.1111/gcbb.12808

Jae Hoon Lee

Papers

Recent advances and future directions in plant and yeast engineering to improve lignocellulosic biofuel production

Improving lignocellulosic biofuel production by CRISPR/Cas9‐mediated lignin modification in barley