Applications of yeast flocculation in biotechnological processes

A review on the main aspects associated with yeast flocculation and its application in biotechnological processes is presented. This subject is addressed following three main aspects – the basics of yeast flocculation, the development of “new” flocculating yeast strains and bioreactor development. In what concerns the basics of yeast flocculation, the state of the art on the most relevant aspects of mechanism, physiology and genetics of yeast flocculation is reported. The construction of flocculating yeast strains includes not only the recombinant constitutive flocculent brewer’s yeast, but also recombinant flocculent yeast for lactose metabolisation and ethanol production. Furthermore, recent work on the heterologous β-galactosidase production using a recombinant flocculent Saccharomyces cerevisiae is considered. As bioreactors using flocculating yeast cells have particular properties, mainly associated with a high solid phase hold-up, a section dedicated to its operation is presented. Aspects such as bioreactor productivity and culture stability as well as bioreactor hydrodynamics and mass transfer properties of flocculating cell cultures are considered. Finally, the paper concludes describing some of the applications of high cell density flocculation bioreactors and discussing potential new uses of these systems.Fundação para a Ciência e a Tecnologia (FCT) – PRAXIS XXI - BD11306/97

Socio Demographic and Clinical Features of The Malaria Cases

Objective: To study the sociodemographic profile of malaria cases admitted on the basis of clinical features. Methods: With purposive sampling 100 cases were taken in these studies who were admitted with clinical findings of fever at Sayajirav Gyakwad Hospital, Vadodara. The indoor patients from April 2006 to October 2006 were retrieved using a prepared case sheet performa on the basis of patient’s demographic profile and clinical findings. Results: Out of 100 cases 66 patients were male and 44 female. Highest age group among male (46.96) as well as female (47.05) patients were more than 30 year age. The infection rate was higher among the younger age group. Hepatomegaly (46%), spleenomegaly (56%) and jaundice (49%) were associated with malaria. Interpretation and Conclusion: Malaria is responsible for major health concern in this region, particularly in rainy season and is found to affect comparatively the younger adult population

Isolation Of Vibrio Cholera O1 During an Outbreak of Acute Gastroenteritis In Dahod District, Gujarat

Background: Epidemics of cholera caused by Vibrio cholerae O1 or O139 have been reported from different parts of India. It is necessary to investigate Acute Gastroenteritis cases for the presence of V. Cholerae by stool sample analysis in the reference laboratory. Objectives: To analyze stool samples for the presence of V. cholerae and subtypes in confirmed cases of cholera during an outbreak of Acute Gastroenteritis. Materials and Methods: During an outbreak of Acute Gastroenteritis, total 171 stool samples and 5 water samples were collected by local health authorities and sent to the Microbiology Department, Medical College, Baroda for the analysis. Results: Out of total 171 stool samples, 46 stool samples were found positive (27%) for V. cholerae O1 biotype El Tor, serotype Ogawa as a sole pathogen. Highest positivity (50%) was found in age group of 0-15 years. Positivity rate was same among both the genders. Water samples showed presence of coliform bacilli with high MPN (most probable number) count. Faecal coliform was also found in both the water samples. Conclusion: V. cholerae O1 biotype El Tor, serotype Ogawa was confirmed as a sole pathogen in stool samples confirm the cholera outbreak and water contamination was supported by the presence of Faecal coliform organisms in water samples

Urinary Tract Infections (UTI) Among Patients at G.G. Hospital & Medical College, Jamnagar

Background: It has been estimated that symptomatic urinary tract infections (UTI) occurs in as many as 7 million visits to emergency units and 100,000 hospitalizations annually. UTI has become the most common hospital-acquired infection, accounting for as many as 35% of nosocomial infections, and it is the second most common cause of bacteraemia in hospitalized patients. Objective: (1) To detect the prevalence rate of bacterial infection among urinary isolates from patients having UTI. (2) To detect prevalence rate of drug resistance among pathogen isolate from patients having UTI. Results: The prevalence of Urinary Tract Infections (UTI) was evaluated in 3046 patients attending G.G. Hospital & Medical College, Jamnagar. Results showed 1416 (46.48%) patients were positive. The most common organisms were Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, and Proteus mirabilis. In-vitro antibiotic susceptibility tests revealed that the gram negatives bacteria were sensitive to quinolones (Gatifloxacin, levofloxacin) and meropenum, while the gram positive isolates were sensitive to linazolid, erythromycin & quinolones (Gatifloxacin, levofloxacin ). Conclusion: The findings suggested the need for constant monitoring of susceptibility of specific pathogens in different populations to commonly used anti-microbial agents

Hybrid direct carbon fuel cells and their reaction mechanisms—a review

As coal is expected to continue to dominate power generation demands worldwide, it is advisable to pursue the development of more efficient coal power generation technologies. Fuel cells show a much higher fuel utilization efficiency, emit fewer pollutants (NOx, SOx), and are more easily combined with carbon capture and storage (CCS) due to the high purity of CO2 emitted in the exhaust gas. Direct carbon (or coal) fuel cells (DCFCs) are directly fed with solid carbon to the anode chamber. The fuel cell converts the carbon at the anode and the oxygen at the cathode into electricity, heat and reaction products. The use of an external gasifier and a fuel cell operating on syngas (e.g. integrated gasification fuel cells) is briefly discussed for comparative purposes. Awide array of DCFC types have been investigated over the last 20 years. Here, the diversity of pre-commercialization DCFC research efforts is discussed on the fuel cell stack and system levels. The range of DCFC types can be roughly broken down into four fuel cell types: aqueous hydroxide, molten hydroxide, molten carbonate and solid oxide fuel cells. Emphasis is placed on the electrochemical reactions occurring at the anode and the proposed mechanism(s) of these reactions for molten carbonate, solid oxide and hybrid direct carbon fuel cells. Additionally, the criteria of choosing the ‘best’ DCFC technology is explored, including system design (continuous supply of solid fuel), performance (power density, efficiency), environmental burden (fresh water consumed, solid waste produced, CO2 emitted, ease of combination with CCS) and economics (levelized cost of electricity)