Substrates' and products' inhibition in fructanase production by a new Kluyveromyces marxianus CF15 from Agave tequilana fructan in a batch reactor.

This study focuses on fructanase production in a batch reactor by a new strain isolated from agave juice (K. marxianus var. drosophilarum) employing different Agave tequilana fructan (ATF) concentrations as substrate. The experimental data suggest that the fructanase production may be inhibited or repressed by high substrate (50 g/L) and ethanol (20.7 g/L) concentrations present in culture medium. To further analyze these phenomena an unstructured kinetic mathematical model taking into account substrate and products inhibition was proposed and fitted. The mathematical model considers six reaction kinetics and the ethanol evaporation, and predicts satisfactorily the biomass, fructan, glucose, fructose, ethanol, and fructanase behavior for different raw material initial concentrations. The proposed model is the first to satisfactorily describe the production of fructanase from branched ATF with a new strain of K. marxianus.

Health-related quality of life of rheumatic disease patients treated in a specialized IPS in Medellin, Colombia.

PURPOSE: To compare Health-Related Quality of Life (HRQOL) profiles and their associated factors in people with rheumatoid arthritis (RA), spondyloarthritis (SpA), fibromyalgia (FM) and rheumatoid comorbidity treated in a specialized health center (SHC) in Medellin, Colombia. METHODS: A cross-sectional analytical study was performed with 93 RA patients, 30 SpA patients, 41 primary FM patients and 48 secondary FM patients with a concurrent diagnosis of RA or SpA. A demographic, socioeconomic, and clinical survey (the IPAQ, International Physical Activity Questionnaire) and the SF-36 survey validated in Medellin were administered. The statistical analyses were executed using SPSS 21.0 Results. Significant differences were found in all HRQOL dimensions among the patients, with physical performance perceived as the worst in the four groups. FM had the worst HRQOL profile, whereas the least affected group was SpA. Patients with RA and rheumatoid comorbidity shared similar HRQOL scores. The years of study, age and economic satisfaction variables were associated with the physical performance, vitality, social functioning, and mental health domains. CONCLUSION: The HRQOL profile was negative in patients with rheumatic diseases and lower in patients with FM. Additionally, variables or subgroups with greater deterioration were identified. This information will be useful for health activities and generate evidence in favor of incorporating HRQOL measurements into rheumatology services to complement clinical evaluations.

Production of fructanase by a wild strain of Saccharomyces cerevisiae on tequila agave fructan.

A new wild strain of Saccharomyces cerevisiae (CF3) isolated from tequila must was evaluated for production of fructanase on Agave tequilana Weber fructan (FT). Fructanase activity (F) was assessed by a 3(3) factorial design (substrate, temperature and pH). High enzymatic activity (31.1 U/ml) was found at 30 °C, pH 5, using FT (10 g/l) as substrate. The effect of initial substrate concentration on F (FT0, 5.7-66 g/l) was studied and it was found that F was highest (44.8 U/ml) at FT0 25 g/l. A 2(2) factorial experimental design with five central points was utilized to study the effect of stirring and aeration on fructanase activity; stirring exhibited a stronger effect on F. The ratio fructanase to invertase (F/S) was 0.57, which confirms that the enzymes are fructanase. Crude fructanase reached high substrate hydrolysis (48 wt%) in 10 h. It is shown that S. cerevisiae CF3 was able to produce large amounts of fructanase by growing it on fructan from A. tequilana.