Sugars metabolism and ethanol production by different yeast strains from coffee industry wastes hydrolysates

Significant amounts of wastes are generated by the coffee industry, among of which, coffee silverskin (CS) and spent coffee grounds (SCG) are the most abundantly generated during the beans roasting and instant coffee preparation, respectively. This study evaluated the sugars metabolism and production of ethanol by three different yeast strains (Saccharomyces cerevisiae, Pichia stipitis and Kluyveromyces fragilis) when cultivated in sugar rich hydrolysates produced by acid hydrolysis of CS and SCG. S. cerevisiae provided the best ethanol production from SCG hydrolysate (11.7 g/l, 50.2% efficiency). On the other hand, insignificant (<= 1.0 g/l) ethanol production was obtained from CS hydrolysate, for all the evaluated yeast strains, probably due to the low sugars concentration present in this medium (approx. 22 g/l). It was concluded that it is possible to reuse SCG as raw material for ethanol production, which is of great interest for the production of this biofuel, as well as to add value to this agro-industrial waste. CS hydrolysate, in the way that is produced, was not a suitable fermentation medium for ethanol production; however, the hydrolysate concentration for the sugars content increase previous the use as fermentation medium could be an alternative to overcome this problem. (C) 2011 Elsevier Ltd. All rights reserved.

ADOPTING LEED CERTIFICATION IN LODGING FACILITIES: GREENING THE HOSPITALITY INDUSTRY

The research intended to analyze the adoption process of the green certification "Leadership in Energy and Environmental Design" (LEED) from the hotel sector establishments that has already adopted it. For its concretization it was proceeded a bibliographical research, secondary fact-gathering in journals, institutional sites and documentaries, and primary fact-gathering by means of semi structured interviews carried out with responsible people of the certified hotels and of the responsible entity of the certification in Brazil (Green Building Council Brazil). There were 21 interviewee, being 02 of the GBC Brazil and 19 of means of lodging (31% of the certified). For data analysis, it was utilized content analysis technique with the aid of ATLAS.ti software. The results permitted to identify the chronology of the processes of certification and the profile of the hotel categories that adopt the LEED program. Beyond that, the interviews enabled the discussion of the initial motivations for seeking the certification, as well the advantages and the obstacles perceived regarding its adoption.

Institutional arrangements in the emerging biodiesel industry: Case studies from Minas Gerais-Brazil

Connecting (small) family farmers to the emerging biodiesel industry requires careful design of the institutional arrangements between the producers of oil crops and the processing companies. According to institutional economics theory, the design of effective and efficient arrangements depends on production and transaction characteristics, the institutional environment, and the organizational environment supporting the transaction between producers and the industry. This paper presents a comparative study on two cases in the feedstock-for-biodiesel industry in the state of Minas Gerais, Brazil. The two case studies represent the production and transaction system of soybeans (Glycine max L Merrill) and castor beans (Ricinus communis L). Important elements of effective and efficient institutional arrangements are farmer collective action, availability of technical and financial support, and farmer experience with particular crops. (C) 2011 Elsevier Ltd. All rights reserved.