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.
Citations
More filters
TL;DR: During screening of vapours emitted by leaf extracts of 30 species of higher plants against Penicillium italicum causing blue mould rot of mandarins, the vapours of Ageratum conyzoides exhibited the strongest toxicity inhibiting the mycelial growth of the test fungus completely.
86 citations
TL;DR: In this paper, solid phase microextraction followed by HPLC was used for the determination of indole-3-acetic acid (IAA), abscisic acid (ABA), indole 3-butyric acid (IBA), and 1-naphthylacetic acids (NAA) in plant samples.
Abstract: Solid-phase microextraction followed by HPLC was used for the determination of indole-3-acetic acid (IAA), abscisic acid (ABA), indole-3-butyric acid (IBA) and 1-naphthylacetic acid (NAA) in plant samples. Parameters influencing performance, including pH, salinity, extraction time, fiber coating and temperature, were optimized. A Carbowax-coated fiber was chosen for determination due to much higher extraction efficiency compared to polyacrylate fibers. The dynamic ranges spanned over three orders of magnitude. The LOD/(LOQ) values of the target compounds in pure water were 0.149(0.497), 0.442(1.472), 0.121(0.403), 0.058(0.193) μg L−1 for IAA, ABA, IBA and NAA respectively. The method was successfully applied to the analysis of xylem fluid from Musa basjoo stem obtaining recoveries of 98.85% (IAA), 94% (IBA) and 94.30% (NAA). The method was also successfully applied to the analysis of these four target compounds in the hyperaccumulating plant, Viola baoshanensis. The results matched quite well with ones obtained by solid phase extraction followed by HPLC. The method developed was superior when applied to liquid samples because matrix effects could be eliminated.
86 citations
TL;DR: A promising method using aquatic plants to sorb metals from secondary treated municipal wastewater is examined in the study as discussed by the authors, which reveals a positive and significant correlation between percent removal of heavy metals from the wastewater and increase in the plant tissues.
85 citations
TL;DR: A tentative structure is presented, showing that it is composed by a very branched and, possibly, repetitive structure of seven residues in the arabinan backbone.
85 citations
TL;DR: The increased activation energies below approximately 12 °C, with consequent decreased rates of reaction for the photoreduction of NADP +, would result in impaired photosynthetic activity at chilling temperatures, which could explain the changes in chloroplast structure and function when chilling-sensitive plants are exposed to chilling temperatures.
85 citations
References
More filters
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