The Determination of Nitrogen in Biological Materials

Light-driven increase in carbon yield is linked to maintenance in the proteorhodopsin-containing Photobacterium angustum S14

“…Particulate organic carbon and PON were measured from triplicate samples using a standard protocol: a volume of 5 ml (“high” substrate experiments) and 10 ml (“low” substrate experiments) were filtered through glass fiber filters (GF/F, Whatman, UK), which were finally placed in glass vials, dried for 8 h, and acidified with concentrated HCl for at least 8 h and dried again. All used filters as well as glass vials had been pre-combusted at 450°C for at least 12 h. Carbon and nitrogen was measured with a Series II 2400 CHNS/O Analyzer (Perkin-Elmer, USA) using a modified Dumas method ( Jacobs, 1965 ). Final POC and PON values were subject to an outlier analysis where any of the triplicate samples whose value was higher than twofold or lower than 0.5 of the standard deviation of the remaining two samples was considered as an outlier.…”

Environmental conditions, particle flux and sympagic microalgal succession in spring before the sea-ice break-up in Adélie Land, East Antarctica

“…After a 100% acetone extraction in the dark at 4Á78C, following procedures described by Neveux & Lantoine (1993) POC and PON were determined on homogenized sediment trap material, selected ice and water samples, after filtration on pre-combusted Whatman GF/F filters. The filters were then acidified with 37 % HCl vapours for 8 h, dried at 508C and stored in a dessicator with drierite for later analyses on a Perkin Elmer 2400 Series II CHNS/ O Elemental Analyzer following the modified Delmas method described by Jacobs (2006).…”

Analytical Chemistry of Element Determination (Non‐Nuclear and Nuclear)

“…Over the past two or three decades, the most commonly applied decomposition procedures for foods and related biological materials have been conventional wet ashing (digestion) and dry ashing, with increased current interest in microwaveassisted wet digestion and slurry preparation. Subsets of these and other techniques used for specific applications, of more limited applicability and used more sporadically include: no treatment or direct use of liquid Ihnat (2003); based on the classification scheme of Sansoni and Panday (1983) with additions from their text and other sources: (Bock 1979, Laporte et al 1975, Ihnat 2000b, Taylor et al 1997, Lamble and Hill 1998, de Bono and Velosa 1991Van Loon 1985, Williams 1978, Baruthio et al 1988, Smith and Arsenault 1996, Ure et al 1988, Gorsuch 1967, Koch and Koch-Dedic 1964, Joslyn 1970, Tölg 1983, Bendicho and de Loos-Vollebregt 1991, Hoenig 2001, Jacobs 1978, Carey and Caruso 1992, FAO 1980, Krause et al 1995, Gorsuch 1965, Langmyhr and Wibetoe 1985, Dunlop 1961, Gorsuch 1959, Gustin and Ogg 1965, Stoeppler 1997a, Totland et al 1992, Burguera and Burguera 1998a, Ure 1975, DeMenna 1994, Shamberger 1983, Watson 1994, Boyer and Horwitz 1986, Olson et al 1973, M...…”

“…The review by Nebesar (1971Nebesar ( /1972 is an excellent overview by an experienced analyst on specialized instruments for the determination of sulfur by the combustion method. Jacobs (1978) writes an excellent review on the determination of nitrogen in biological materials including the Dumas method, mention of which is also in the review by Fleck (1974) on micro-determination of nitrogen. Regarding applications, the paper by Kirsten (1979), on automatic methods for the simultaneous determination of carbon, hydrogen, nitrogen, and sulfur, and for sulfur alone in organic and inorganic materials, is one of the nice, careful studies by one of the more recent workers in this old established technique.…”

“…The contribution by Gustin and Ogg (1965) on organic analysis: nitrogen is an example of excellent, thorough coverage of classical methods of analysis for this important nutrient, including the Kjeldahl method and others. Fleck (1974) and Jacobs (1978) provide short review of methods for the micro-determination of nitrogen covering the Kjeldahl method, Dumas combustion related methods and miscellaneous methods.…”