Biotransformation of beta-myrcene to geraniol by a strain of Rhodococcus erythropolis isolated by selective enrichment from hop plants.

The biocatalytic generation of high-value chemicals from abundant, cheap and renewable feedstocks is an area of great contemporary interest. A strain of Rhodococcus erythropolis designated MLT1 was isolated by selective enrichment from the soil surrounding hop plants, using the abundant triene beta-myrcene from hops as a sole carbon source for growth. Resting cells of the organism were challenged with beta-myrcene, and the major product of biotransformation was determined by mass spectrometric analysis to be the monoterpene alcohol geraniol. Controls demonstrated that the product was biogenic and that an aerobic environment was required. The ability to transform beta-myrcene was shown to be restricted to cells that had been grown on this substrate as sole carbon source. Pre-incubation of cells with the cytochrome P450 inhibitors metyrapone or 1-aminobenzotriazole reduced geraniol production by 23% and 73% respectively, but reduction in activity was found not to correlate with the inhibitor concentration. A comparative analysis of insoluble and soluble cell extracts derived from cells of MLT1 grown on either beta-myrcene or glucose revealed at least four proteins that were clearly overproduced in response to growth on beta-myrcene. Mass spectrometric analysis of tryptic digests of three of these protein bands suggested their identities as an aldehyde dehydrogenase, an acyl-CoA dehydrogenase and a chaperone-like protein, each of which has a precedented role in hydrocarbon metabolism clusters in Rhodococcus sp. and which may therefore participate in a beta-myrcene degradation pathway in this organism.

Mangifera sylvatica (Wild Mango): A new cocoa butter alternative.

Cocoa butter is the pure butter extracted from cocoa beans and is a major ingredient in the chocolate industry. Global production of cocoa is in decline due to crop failure, diseases and ageing plantations, leading to price fluctuations and the necessity for the industry to find high quality cocoa butter alternatives. This study explored the potential of a wild mango (Mangifera sylvatica), an underutilised fruit in south-east Asia, as a new Cocoa Butter Alternative (CBA). Analyses showed that wild mango butter has a light coloured fat with a similar fatty acid profile (palmitic, stearic and oleic acid) and triglyceride profile (POP, SOS and POS) to cocoa butter. Thermal and physical properties are also similar to cocoa butter. Additionally, wild mango butter comprises 65% SOS (1, 3-distearoyl-2-oleoyl-glycerol) which indicates potential to become a Cocoa Butter Improver (an enhancement of CBA). It is concluded that these attractive properties of wild mango could be prompted by a coalition of policy makers, foresters, food industries and horticulturists to promote more widespread cultivation of this wild fruit species to realise the market opportunity.

Generation, capture, and utilization of industrial carbon dioxide.

As a carbon-based life form living in a predominantly carbon-based environment, it is not surprising that we have created a carbon-based consumer society. Our principle sources of energy are carbon-based (coal, oil, and gas) and many of our consumer goods are derived from organic (i.e., carbon-based) chemicals (including plastics, fabrics and materials, personal care and cleaning products, dyes, and coatings). Even our large-volume inorganic-chemicals-based industries, including fertilizers and construction materials, rely on the consumption of carbon, notably in the form of large amounts of energy. The environmental problems which we now face and of which we are becoming increasingly aware result from a human-induced disturbance in the natural carbon cycle of the Earth caused by transferring large quantities of terrestrial carbon (coal, oil, and gas) to the atmosphere, mostly in the form of carbon dioxide. Carbon is by no means the only element whose natural cycle we have disturbed: we are transferring significant quantities of elements including phosphorus, sulfur, copper, and platinum from natural sinks or ores built up over millions of years to unnatural fates in the form of what we refer to as waste or pollution. However, our complete dependence on the carbon cycle means that its disturbance deserves special attention, as is now manifest in indicators such as climate change and escalating public concern over global warming. As with all disturbances in materials balances, we can seek to alleviate the problem by (1) dematerialization: a reduction in consumption; (2) rematerialization: a change in what we consume; or (3) transmaterialization: changing our attitude towards resources and waste. The "low-carbon" mantra that is popularly cited by organizations ranging from nongovernmental organizations to multinational companies and from local authorities to national governments is based on a combination of (1) and (2) (reducing carbon consumption though greater efficiency and lower per capita consumption, and replacing fossil energy sources with sources such as wind, wave, and solar, respectively). "Low carbon" is of inherently less value to the chemical and plastics industries at least in terms of raw materials although a version of (2), the use of biomass, does apply, especially if we use carbon sources that are renewable on a human timescale. There is however, another renewable, natural source of carbon that is widely available and for which greater utilization would help restore material balance and the natural cycle for carbon in terms of resource and waste. CO(2), perhaps the most widely discussed and feared chemical in modern society, is as fundamental to our survival as water, and like water we need to better understand the human as well as natural production and consumption of CO(2) so that we can attempt to get these into a sustainable balance. Current utilization of this valuable resource by the chemical industry is only 90 megatonne per year, compared to the 26.3 gigatonne CO(2) generated annually by combustion of fossil fuels for energy generation, as such significant opportunities exist for increased utilization of CO(2) generated from industrial processes. It is also essential that renewable energy is used if CO(2) is to be utilized as a C1 building block.

Enzymatic esterification of lavandulol--a partial kinetic resolution of (S)-lavandulol and preparation of optically enriched (R)-lavandulyl acetate.

The asymmetric esterification of the racemic primary alcohol lavandulol was achieved using lipase B from Candida antarctica and acetic acid as acyl donor in 80% yield. The enantioselectivity of the process was characterised, and a preparative resolution of 25 mM racemic lavandulol, stopped at approx. 55% conversion, yielded (S)-lavandulol in 42% yield and 52% e.e. and (R)-lavandulyl acetate in 51% yield and 48% e.e.