Determination in plants

Heat-flux corrosion rates can also be determined in plant tests using steam-heated tubular specimens which are weighed or callipered. 

Paul, J.L. and Carlson, R.M. (1968) Nitrate determination in plant extracts by the nitrate electrode. Journal of Agricultural and Food Chemistry 16, 766-768. 

An FIPLC method using electrochemical detection in the reductive mode for the determination of artemether 28a and its metabolite dihydroartemisinin 29a <1997JCFI(B)145> and for the simultaneous quantification of artesunate 31 and dihydroartemisinin 29a in plasma has been developed <1997JCFI(B)259, 1998JCFI(B)201>. An effective reversed-phase FIPLC method using electrochemical and UV detection has been developed for the simultaneous determination in plant extracts of artemisinin and its bioprecursors such as arteannuin B 32a, and artemisitene 27 <1995JNP798, 2001JIC489>. 

DB Rodriguez-Amaya. Critical review of provitamin A determination in plant foods. J Micronutr Anal 5 191-225, 1989. 

In a standard official metho d [53,54], potassium is determined in plant material by first digesting the sample with 60% perchloric acid 70% mlm nitric acid 1 3 v/v followed by extraction of the residue with 2 M hydrochloric acid or by dry combustion at 500 °C followed by extraction with 6 M hydrochloric acid. Potassium in the extracts is determined flame-photometrically. There is no significant interference from other elements. See also Sects. 7.34.1 and 7.34.7. 

Sodium has been determined in plant material by a standard official method [ 79 ]. In this method, the plant material is first digested with perchloric acid 60% m/m nitric acid 70% m/v (1 4 v/v), the residue is dissolved in hydrochloric acid, and then it is analysed by AAS at the 589.0 nm emission line. See Sect. 7.34.1. 

Heanes [97] has described a method for determining copper, manganese and zinc in ashed plant extracts by flame AA spectrophotometry after cobalt and molybdenum have been assayed on separate aliquots of the same plant extracts by a spectrophotometric procedure [102]. (See Sect. 7.34.3). Ashing aids were necessary to maintain accuracy in the determinations. Concentrations of up to 3.5% m/m of silicon and calcium and 4% m/m of chlorine in the plants did not affect the determinations, but in some instances lower concentrations were determined in plant samples containing equal or higher levels of both added silica and calcium. 

Specific methods have been described for the determination in plants of pyruvic acid by gas chromatography (GC) [1] and phytic acidbyspectrophotometric methods [2,3]. 

Fluoride levels can be determined in plant tissues by leaf, stem, or root analysis (15-17). Rates of accumulation can therefore be calculated by the relationship of plant tissue levels to ambient air levels in terms of exposure time (18—20). The accumulation of fluoride in plants is similar to the accumulation of heavy metals in biological systems. The chronic exposure of the plant to low levels of fluoride causes the plant to accumulate fluoride. This can be measured quantitatively, and the level can be related in a quantitative manner to the intensity of symptom expression. 

Tropane alkaloids are an important class of natural products possessing different and interesting pharmacological activities. Hyoscyamine (atropine in the racemate form), scopolamine, and cocaine are the major representatives of this class. They are commonly found in plant materials, mainly in genera belonging to three families Solanaceae, Erythroxylaceae, and Convolvulaceae. The importance of these compounds requires that there are accurate analytical methods for their determination in plants and in biological matrices. This chapter describes the state-of-the-art of analytical procedures (extraction and analysis) for analyzing tropane alkaloids. 

Ketose, Determination, in Plant Products (de Whalley and Gross). 1 307... 

The method with azomethine H has been used for determining boron in plant materials [75], biological samples [76], plants [77], soils [77-79], water [80], sewage [4,81], rocks and bituminous [22,55,82], steel [47], copper, nickel, and cobalt alloys [9], boron nitride [83], and fertilisers [84]. Azomethine H has been utilized in automatic determination of boron [81] and in flow injection analysis (FIA) [75]. Boron has also been determined in plants and soils with the use of 4-methoxyazomethine H [85],... 

Conditions see Table II Assay Procedures The activity of acid invertase (free and bound) was determined in plant material that was frozen in liquid nitrogen, freeze-dried, pulverized, homogenized with mercaptoethanol, centrifuged at 25,000g for 30 min (4WC) solution and residue were dialyzed (48 h, 4WC) and then incubated with sucrose (pH 4.7, 1 h, 30 0 and glucose was analyzed electrochemically. 

Nitrate determination in plant digests. With zone sampling one standard solution was sufficient to circumvent the influence of reducing agents in the extracts on the development of the colourforming reaction [350]. 

A.L.D. Comitre, B.F. Reis, Automatic flow procedure based on multicommutation exploiting liquid—liquid extraction for spectrophotometric lead determination in plant material, Talanta 65 (2005) 846. 

Rodriguez, D.B., Raymundo, L.C., Lee, T.C., Simpson, K.L., and Chichester, C.O. 1976. Carotenoid pigment changes in ripening Mormordica charantia fruits. Ann. Bot. 40, 615-624. Rodriguez-Amaya, D.B. 1989. Critical review of provitamin A determination in plant foods. 

Kowalenko CG and Van Laerhoven C (1998a) Total suljur determination in plant tissue. In Kalra YP, ed. Handbook of reference methods for plant... 

In general, two methods are used to determine trace amounts of fluorine in different natural materials, fodder, and foodstuffs. These are photometric determination based on the reaction of fluoride ions with the lanthanum-alizarin complexing agent and electrochemical measurements of fluoride concentrations by means of F-selective electrodes (Brill 1995). When measuring fluorine in the fluids and tissues of mammals, it is pre-separated by distillation or diffusion. As applied to fluorine determination in plants, good results are demonstrated using alkaline hydrolysis with subsequent fluoride concentration measurements, or in an acid medium by means of ion-selective potentiometry (Galloway et al. 1975). 

Lindberg, P., "Selenium Determination in Plant and Animal Material, and... 

Analytical Techniques for Molybdenum Determination in Plants and Soils... 

Jopke, P., Bahadir, M., Fleckenstein, J. Schnug, E. (1996). Iodine Determination In Plant Materials. Communications In Soil Science And Plant Analysis, Vol.27, No.3-4, pp 741-751, ISSN 1532-2416... 

M-acetyl glucosamine chitin oligosaccharides (NA-COSs) play a crucial role in plant biotechnology, secondary metabolites production, plant resistance (chitin in cell walls), and symbiotic bacteria released in root nodules for nitrogen fixation (Asaoka 1996). It has an estabUshment of a host-specific symbiosis between legumes, and their rhizobia were determined in plants (Cohn et al. 1998). 

Classical reagents such as azomethine-H and curcu-min are frequently used in boron determination. Azomethine-H is used, for example, in boron determination in plants, geochemical materials, and soils. Curcumin is used in determination of boron as an impurity in silicon-doped galHum arsenide used in electronics and in high-purity molybdenum. The microgram per gram limit of detection (LOD) is attained when curcumin or 4-methoxy-azomethine-H (420 nm) is used. However, boron is also determined by the formation of the macrobicyclic complex Fe(Nx) (3) (BOH) (2) in the nioxime-boric acid-Fe(II) system (447 nm). 

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