Uruguay has achieved a 7% annual reduction in greenhouse gas emissions, the government announced recently. The figures came from a study conducted by Alcoholes de Uruguay (Alur).

The study was carried out by the Centre for Energy, Environmental and Technological Research of Spain, at the request of Alur and the National Energy Directorate, with the support of the National Research and Innovation Agency. The research suggests that when biodiesel is used as a substitute for oil-based diesel, greenhouse gas emissions are reduced by 70%, while bioethanol reduces emissions by 66%.

These results show that Uruguay is on course to meet its obligations under the Paris Climate Agreement, which set a target of a 15% reduction in the consumption of petroleum-derived fuels in transport.

Alur produces bioethanol from several feedstocks, including sugarcane and sorghum. The company also produces biodiesel from soybean and canola oil as well as oil used for frying.

The Slovenian government has recently adopted a strategy on alternative fuels where the registration of new diesel and petrol cars would be prohibited after 2030. The government expects that by 2030, 17% of the fleet in Slovenia, roughly 200,000 cars, will already be either electric vehicles or plug-in hybrids. The strategy extends to cargo transport as well, but the goals are more modest.

The government did not opt for an outright ban, instead putting a ceiling on a car's carbon footprint of 50 grams of CO₂ per kilometer. Currently, only electric vehicles and plug-in hybrids conform to the ceiling. Latest data from car dealers show that 900 electric or hybrid vehicles were sold in the first eight months of this year, almost triple the number sold in the same period in 2016.

Slovenia has one of the highest car ownership rates in the world, 523 cars per 1,000 population as of last year.

David Kamanda Ngugi from King Abdullah University of Science and Technology in Saudi Arabia led a team of scientists from various research institutions to study the significance of symbionts in surgeonfishes and their roles in the digestive processes of their hosts. Herbivorous surgeonfishes are a group of reef fish that feed on marine algae.

Analysis revealed the wide diversity of microbiota involved in the degradation of algal biomass in these fishes. The microbiota was found to be simple relative to the complex microbiota of terrestrial herbivores. Analysis also found that over 90% of the enzymes for deconstructing algal polysaccharides come from members of "Candidatus epulopiscium" and other related giant bacteria.

These findings show that the metabolically distinct symbionts in hosts are key to digesting algae biomass and polysaccharides and could be pave the way for the advancement of algal biofuels.

Conversion of plant biomass into biofuels and bioproducts is vital to establish a robust biofuel industry. However, this requires a host that is capable of both assimilation of carbon sources and diversion of their metabolites toward specific bioproducts.

Junko Yaegashi of Joint BioEnergy Institute and Sandia National Laboratories evaluated the yeast Rhodosporidium toruloides for its ability to convert lignocellulose into bisabolene and amorphadiene, which have biofuel and pharmaceutical applications, respectively.

The team found that R. toruloides can efficiently convert a mixture of glucose and xylose from lignocellulose into these bioproducts. Moreover, its growth and productivity were enhanced in lignocellulosic hydrolysate. R. toruloides was also found to have superior growth in corn stover hydrolysates pretreated either with ionic liquid choline α-ketoglutarate or alkaline.

This study highlights the compatibility of R. toruloides with bioprocesses associated with lignocellulosic biorefineries and demonstrates its ability to produce valuable terpenes.

Microalgae are among the most promising species for producing renewable biofuels and chemicals. Ethanol and butanol are clean energy sources and are good alternatives to gasoline. However, synthesis of these two biofuels has not been achieved due to low tolerance of algal cells to ethanol or butanol.

Researchers led by Yongguang Jiang from Shenzhen University investigated the metabolic responses of the model green alga Chlamydomonas reinhardtii to ethanol and butanol. The team detected proteins which were differentially regulated by ethanol and butanol. The team found 41 and 59 proteins that were consistently regulated by ethanol and butanol, respectively.

Multiple metabolic processes were affected by ethanol or butanol, and various stress-related proteins, transporters, cytoskeletal proteins, and regulators were induced as the major protection mechanisms against toxicity of the organic solvents.

The study is the first view of the metabolic mechanisms used by C. reinhardtii to defend against ethanol or butanol toxicity. The proteomic analysis provides a resource for investigating potential gene targets for engineering microalgae with enhanced ethanol and butanol tolerance.