Species of cyanobacteria in the genera Synechococcus and Synechocystis are known to be the catalysts of a phenomenon called "whitings", which is the formation and precipitation of fine-grained CaCO3 particles. Whitings occur when the cyanobacteria fix atmospheric CO2 through the formation of CaCO3 on their cell surfaces, which leads to precipitation to the ocean floor and subsequent entombment in mud. Whitings represent one potential mechanism for CO2 sequestration. Research was performed to determine the ability of various strains of Synechocystis and Synechococcus to calcify when grown in microcosms amended with 2.5 mM HCO(3-) and 3.4 mM Ca2+. Results indicated that although all strains tested have the ability to calcify, only two Synechococcus species, strains PCC 8806 and PCC 8807, were able to calcify to the extent that a CaCO3 precipitate was formed. Enumeration of the cyanobacterial cultures during testing indicated that cell density did not appear to have a direct effect on calcification. Factors that had the greatest effect on calcification were CO2 removal and subsequent generation of alkaline pH. Whereas cell density was similar for all strains tested, differences in maximum pH were demonstrated. As CO2 was removed, growth medium pH increased and soluble Ca2+ was removed from solution. The largest increases in growth medium pH occurred when CO2 levels dropped below 400 ppmv. Research presented demonstrates that, under the conditions tested, many species of cyanobacteria in the genera Synechocystis and Synechococcus are able to calcify but only two species of Synechococcus were able to calcify to an extent that led to the precipitation of calcium carbonate.

Ulcerative colitis (UC) is an inflammatory bowel disease that causes gastrointestinal lesions, bleeding, diarrhoea and nutritional complications. Insufficient nutrient intake can additionally deteriorate nutritional status. The present cross-sectional study aimed to determine whether UC patients adhere to national dietary guidelines and to assess their dietary habits. An online questionnaire (n 93) was used to assess health-related conditions, current nutritional knowledge, professional dietary guidance and food avoidance. A 24 h dietary recall (n 81) was used to assess nutrient intakes, which were then compared with the national recommended intake values. The results showed that the nutritional knowledge of participants was limited with unofficial sources being used, including websites. Numerous food groups, predominantly fibre-rich foods and fruit and vegetables, were largely avoided by the participants. Almost half of the study population eliminated foods such as dairy products to alleviate symptoms, possibly unnecessarily. Energy intakes were significantly (P,0·05) lower than the national recommended intake values in women aged 18 -65 years and men aged 18 -60 years. Fat intake exceeded the national recommended intake values (P,0·0001), at the expense of carbohydrate and fibre intakes, which were significantly (P,0·005) lower than the national recommended intake values. Protein intake was significantly high in women aged 19-50 years (P,0·00) and men aged 19-50 years (P, 0·005). Vitamin C, vitamin B 12 and Ca intake levels were overachieved by all participants (P, 0·001), while women aged 19-50 years did not achieve their dietary Fe reference nutrient intake levels (P, 0·001). Osteopaenia, osteoporosis and anaemia were reported by 12, 6 and 31 % of the participants, respectively. Findings indicate that food avoidance may contribute to nutrient deficiencies in UC patients. Low intakes of these food groups, especially during remission, are preventing patients from adhering to dietary guidelines.

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Due to the highly variable nature of biomass resources, establishing a quantitative system for evaluating biomass quality offers tangible benefits for emerging bioeconomy markets. This paper demonstrates an approach for developing a grading system, based on inherent biomass characteristics, to inform markets on how natural variability impacts conversion performance. The case study considers a biochemical biorefining pathway, in which monomeric sugars are fermented to mainly ethanol, while the preliminary demonstration is based on five grass types, typically used as feedstock in this type of biorefinery. Samples of the biomass resources were characterized and converted to carbohydrates using dilute-acid pretreatment and enzymatic hydrolysis. The approach involved three steps: (1) identify key biomass compositional characteristics that impact biochemical conversion performance and fermentable sugar yields using a linear regression approach, (2) assess the range of variability for the key characteristics using a diverse set of biomass resources, and (3) grade ranges of variability based on predicted conversion yields. It was demonstrated that five chemical characteristics, structural glucan, hemicellulose carbohydrates, acid-soluble lignin, acidinsoluble lignin, and total ash, could be used to estimate conversion performance. Five grades were established using a hierarchical cluster analysis. Future research is needed to confirm that these characteristics can predict product yields over multiple pretreatment methods and enzymatic hydrolysis/fermentation conditions. In addition, it would be beneficial to extend a grading system to include other biomass characteristics that impact preprocessing operations, such as grinding and conveying.