Modern methods of plant analysis
01 Jan 1964-
About: The article was published on 1964-01-01 and is currently open access. It has received 1991 citations till now.
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TL;DR: The mycelial biomass of fungi decomposing plant materials may be estimated by use of a chitin (hexosamine) assay technique as discussed by the authors, and the economic coefficient derived is 47 per cent which is similar to that for the utilization of glucose in liquid culture.
Abstract: The mycelial biomass of fungi decomposing plant materials may be estimated by use of a chitin (hexosamine) assay technique. A method is described together with a discussion of its limitations; whatever the sensitivity of the chemical analysis the validity of the biomass estimate rests on the reliability of the conversion from chitin determination to mycelial dry weight. Estimates made on mycelium of Coriolus versicolor during decay of sawdust from Castanea sativa show a constant increase in biomass. The economic coefficient derived is 47 per cent which is similar to that for the utilization of glucose in liquid culture. Estimates of production are not possible due to lack of information concerning rates of hyphal death and autolysis. The estimated extents of mineral nutrient immobilization are 39% for N, 37% for P and 95% for K.
131 citations
TL;DR: Pigments in hazel, aspen, and pin oak leaves were measured from their inception in buds to development of a summer maximum, and through the autumn coloration period to decomposition in dry falling leaves, discussing the usefulness of chlorophyll content as an index of net primary productivity.
Abstract: Pigments in hazel (Corylus americana), aspen (Populus tremuloides), and pin oak (Quercus ellipsoidalis) leaves were measured from their inception in buds to development of a summer maximum, and through the autumn coloration period to decomposition in dry falling leaves. Leaves contained generally high but varyingconcentrations of chlorophyll and carotenoid pigments throughout the summer months. The summer pigment variations among the three species are discussed in the light of the usefulness of chlorophyll content as an index of net primary productivity. During the autumn coloration period, preceding leaf desiccation and fall, chlorophyll decays rapidly, producing low levels of pheophytin with only occasional faint traces of pheophorbide and chlorophyllide during the period of most rapid chlorophyll breakdown. The levels of carotenoids begin declining at the same time as chlorophyll, but at a much slower rate. Violaxanthin disappears most rapidly, followed closely by neoxanthin. Lutein and Beta—carotene a...
131 citations
Cites background from "Modern methods of plant analysis"
...solvent systems (Strain 1938, Goodwin 1952, Watson 1953, Holt and Jacobs 1954, Smith and Benitez 1955, Holden 1962, Colman and Vishniac 1964, Michel-Wolwertz and Sironval 1965, Strain et al. 1965, Strain and Svec 1966)....
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TL;DR: In its presence, the alga particles catalyze the gradual photoreduction of nitrate to nitrite and ammonia, a process that can thus be considered as one of the most simple and relevant examples of Photosynthesis.
Abstract: The dark and light reduction of nitrate and nitrite by cell-free preparations of the blue-green algaAnacystis nidulans has been investigated. The three following methods have been successfully applied to the preparation of active particulate fractions from the alga cells: (a) shaking with glass beads, (b) lysozyme treatment and lysis of the resulting protoplasts, and (c) sonication. The two enzymes of the nitrate-reducing system-namely, nitrate reductase and nitrite reductase-are firmly bound to the isolated pigment-containing particles, and can be easily solubilized by prolonging the vibration or sonication time. Both enzymes-whether solubilized or bound to the particles-depend on reduced ferredoxin as the immediate electron donor. In its presence, the alga particles catalyze the gradual photoreduction of nitrate to nitrite and ammonia, a process that can thus be considered as one of the most simple and relevant examples of Photosynthesis. Some of the properties of nitrate reductase have been studied. Nitrate reductase as well as nitrite reductase are adaptive enzymes repressed by ammonia.
130 citations
TL;DR: The results showed that in fresh mulberry leaves the proximate composition values ranged from 71.13 to 76.13%, and among vitamins ascorbic acid and β-carotene were found to range from 160 to 280 mg/ 100 g and from 10,000 to 14,688.00 µg/100 g, respectively.
Abstract: This study was undertaken to determine the proximate composition, vitamins, minerals and the antinutritional factor tannic acid in leaves of six genotypes of mulberry. The results showed that in fresh mulberry leaves the proximate composition values ranged from 71.13 to 76.68% for moisture, from 4.72 to 9.96% for crude protein, from 4.26 to 5.32% for total ash, from 8.15 to 11.32% for Neutral Detergent Fiber (NDF), from 0.64 to 1.51% for crude fat, from 8.01 to 13.42% for carbohydrate and from 69 to 86 kcal/100 g for energy. In dried mulberry leaf powder, moisture ranged from 5.11 to 7.24%, crude protein from 15.31 to 30.91%, total ash from 14.59 to 17.24%, NDF from 27.60 to 36.66%, crude fat from 2.09 to 4.93%, carbohydrate from 9.70 to 29.64% and energy from 113 to 224 kcal/100 g. Among vitamins ascorbic acid and beta-carotene were found to range from 160 to 280 mg/100 g and from 10,000.00 to 14,688.00 microg/100 g, respectively, in fresh mulberry leaves and from 100 to 200 mg/100 g and from 8438.00 to 13,125.00 microg/100 g, respectively, in dried mulberry leaf powder. The minerals iron, zinc and calcium were observed in the ranges of 4.70-10.36 mg/100 g, 0.22-1.12 mg/100 g and 380-786 mg/100 g, respectively, for fresh mulberry leaves, and 19.00-35.72 mg/100 g, 0.72-3.65 mg/100 g and 786.66-2226.66 mg/100 g, respectively, for dried mulberry leaf powder. The tannic acid ranged from 0.04 to 0.08% in fresh leaves and from 0.13 to 0.36% in dried leaf powder.
130 citations
Cites methods from "Modern methods of plant analysis"
...Ascorbic acid was estimated following method of AOAC (1984). b-Carotene was determined by column chromatography using the method given by Ranganna (1986) with a modification in column packing as prescribed by Goodwin (1995)....
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TL;DR: All the three species of Phyllanthus can be differentiated on the basis of macro and microscopic characters, physico-chemical values, HPTLC fingerprint profile, and detection of phyllanthin and hypophyllanthin as marker components.
129 citations
References
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01 Jan 1963
TL;DR: In this article, a physiologischer Vorgang auf eine enzymatische Wirkung zuruckgefuhrt werden (vgl. S. 301), besteht die folgende Aufgabe darin, Naheres uber die Eigenschaften des beteiligten Enzyms zu ermitteln.
Abstract: Kann ein physiologischer Vorgang auf eine enzymatische Wirkung zuruckgefuhrt werden (vgl. S. 301), so besteht die folgende Aufgabe darin, Naheres uber die Eigenschaften des beteiligten Enzyms zu ermitteln. Hierzu gehoren die Bestimmung der Reaktions- und Substratspezifitat sowie die Ermittlung der Bedingungen, unter denen eine optimale Wirkung des Enzyms gegeben ist. Wesentlich zur Charakterisierung ist ferner die Untersuchung der Stabilitat des Enzyms und dabei insbesondere die Feststellung, ob es sich um ein Ferment handelt, das zur vollen Aktivitat dialysable Cofaktoren benotigt. Falls diese Frage bejaht wird, ist auch die Bestimmung der unerlaslichen Cofaktoren anzuschliesen. Uberdies bietet auch der Nachweis der Lokalisation des Enzyms in der Zelle (oder im Zellverband) eine entscheidende Moglichkeit zur Charakterisierung des Fermentes. Hinzu kommt schlieslich noch die Untersuchung der Wirkung einzelner Inhibitoren1 auf das Enzym, die zu weitgehender Klarung des Reaktionsmechanismus beitragen kann und eine Abgrenzung der Eigenschaften des untersuchten Fermentes gegenuber ahnlichen Enzymen erlaubt.
2 citations
01 Jan 1962
TL;DR: Optical rotation has been found to be one of the most convenient methods of following the denaturation of proteins and rotatory dispersion is capable of providing information on the folding of the polypeptide chain in proteins and the changes accompanying denaturation.
Abstract: Optical rotation has been found to be one of the most convenient methods of following the denaturation of proteins. Generally speaking denaturation can be defined as a process or sequence of processes in which the spatial arrangement of the polypeptide chains within the molecule is changed from that typical of the native protein to a more disordered arrangement (Kauzmann 1959). The terms “configuration”, “conformation” and “state of folding” are widely used for spatial arrangement. It is probably best to follow the suggestion of Blout (1960) and restrict the use of “configuration” to its original sense, i.e. the spatial arrangement around an asymmetric carbon atom, and to use “conformation” for the shape of the molecule in its entirety. The properties discussed in the previous Chapter i.e., viscosity, diffusion, sedimentation, and light scattering — can all furnish information on the overall shape of proteins or other macromolecules and changes in this shape with environment. Thus Doty, Bradbury and Holtzer (1956) were able to show using these methods, together with streaming birefringence, that poly-γ-benzyl-L-glutamate could exist in two conformations, the α-helix and the solvated randomly coiled form, depending on the solvent. The change from α-helix to random coil was accompanied by marked changes in the optical rotatory properties of the polypeptides. It is to be expected that an α-helical structure should contribute to the rotatory power of a polypeptide since helices are asymmetric and not superimposable on their mirror images. The work on polypeptides has shown that rotatory dispersion is capable of providing information on the folding of the polypeptide chain in proteins and the changes accompanying denaturation.
1 citations