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: In this article, a primary screening of the phytochemical contents of seven solvents (petroleum ether, benzene, chloroform, acetone, methanol, ethanol and a mixture of methanoline and ethyl acetate (1:3)) extracts of the seeds of Anamirta cocculus (Linn.) and to evaluate the antibacterial activity of these extracts against five species of pathogenic bacteria.
18 citations
TL;DR: Hypoglycemic activity of Withania somnifera Dunal, Allium sativum Linn.
Abstract: In the present study, the hypoglycemic activity of Withania somnifera Dunal, Allium sativum Linn., Gymnema sylvestre (Retz.) Schult, Ferula foetida (Bunge.) Reg. and Murraya koenigii (L.) Spreng. extracts have been studied in an experimental model of type 1 diabetes. Type 1 diabetes was induced in albino rats by a single intraperitoneal injection of streptozotocin (60 mg/kg). Rats with fasting blood glucose (FBG) more than 250 mg/dl, 72 h after STZ administration, were treated with extracts of above mentioned medicinal plants. The fasting blood glucose was determined every week for 3 weeks by the glucose oxidase method. STZ-administration led to a highly significant elevation in FBG levels. The percent decrease in FBG levels from STZ-induced hyperglycemia was 43.3 + 27.8, 48.2 + 22.4 and 48.2 + 7.9, after 3 weeks of treatment with standardised extracts of Withania somnifera (1.5% withanolides), Allium sativum (0.6% allicin) and Gymnema sylvestre (75% gymnemic acid), respectively. The fall in blood glucose with the herbal extracts was less when compared to insulin. In the vehicle treated group, there was 8.8 + 9.3 percent increase in blood glucose values at the third week of treatment and in insulin treated group, percent decrease in blood glucose from the values obtained at 72 h after STZ-administration was 63.5 + 4.9. Ferula foetida (60% ferulic acid) and Murraya koenigii extracts did not show any hypoglycemic effect in animal model of type 1 diabetes.
18 citations
01 Jan 2010
TL;DR: Suitable use of allelopathic crops in agriculture could reduce the pesticide application and thereby reduce the environmental and food pollution, decrease costs in agriculture, improve food security in poor regions and soil productivity, and increase biodiversity and sustainability in the agro-ecosystem.
Abstract: Allelopathy is a biological process including interactions between two plants through the production of chemical compounds (allelochemicals) that are released by leaching, volatilization, decomposition, or root exudation Hence, allelopathy together with competition is a promising environment-friendly tool especially for weed management However, detailed knowledge of this phenomenon is necessary for its successful application due to very still limited available knowledge Suitable use of allelopathic crops in agriculture could reduce the pesticide application and thereby reduce the environmental and food pollution, decrease costs in agriculture, improve food security in poor regions and soil productivity, and increase biodiversity and sustainability in the agro-ecosystem Weed management in organic agriculture is one of the most difficult aspects of organic farming and uses especially preventive methods that include ways such as cover crops, mulches, green manure, and intercropping in which allelopathy could play an important role Therefore, this review focuses on the possibilities of the allelopathy application especially in organic agriculture Roots of allelopathic plants as cover crops, intercrops, green manure, or so-called smothering crops or decomposing residues release compounds in the soil that are toxic to weeds The weed-suppressive effect is influenced by species, planting date, seeding rate and method, weather, and other factors Decomposition time of plant residues and amounts of biomass are important factors of weed control by mulching Annual, biennial, or perennial herbaceous plants in a pure or mixed stand can be grown for these purposes Biofumigation is the name for one type of allelopathy that includes the effects of the chemicals, ie, highly toxic isothiocyanates, produced by Brassica green manure The balance in the crop rotation is necessary due to possible autotoxicity These days, allelopathic plants as catch crops or trap crops found utilization in plant protection of tropical regions against parasite weeds, because they can reduce the parasite seed bank by 72% Other applications of allelopathy for weed control include the use of plant residues as an herbicide agent, eg, water extracts, pellets, flours, by-products of crop processing, etc Sorgaab, an extract of sorghum, is produced commercially as a natural herbicide Allelopathic compounds act as repellents for herbivorous pests, so the same strategy used in weed control could be effective against pests and pathogens, eg, push–pull strategy All possible applications of allelopathy need to combine with other methods of plant protection Newly investigated pollen allelopathy could reduce reproductive ability of wind pollination annual weeds Pollen of allelopathic species would be artificially dusted on the stigmatic surface of other plants This phenomenon is yet to be studied and field tested The new crop varieties with elevated allelopathic activity could be a great chance not only for organic farming Hybridization could be the promising method However, allelopathic activity was identified as a quantitative trait and therefore this characteristic is affected by both genetic effects and environmental conditions
18 citations
TL;DR: It is shown that an alternative visualization technique, UV shadowing, readily detects a novel, mitochondrion-specific small RNA in Acanthamoeba castellanii mitochondrial RNA preparations, and that this RNA species is, in fact, a 5S rRNA encoded by the A. castellaniai mitochondrial genome.
Abstract: Although 5S rRNA is a highly conserved and universal component of eubacterial, archaeal, chloroplast, and eukaryotic cytoplasmic ribosomes, a mitochondrial DNA-encoded 5S rRNA has so far been identified only in land plants and certain protists. This raises the question of whether 5S rRNA is actually required for and used in mitochondrial translation. In the protist Acanthamoeba castellanii, BLAST searches fail to reveal a 5S rRNA gene in the complete mitochondrial genome sequence, nor is a 5S-sized RNA species detectable in ethidium bromide-stained gels of highly purified mitochondrial RNA preparations. Here we show that an alternative visualization technique, UV shadowing, readily detects a novel, mitochondrion-specific small RNA in A. castellanii mitochondrial RNA preparations, and that this RNA species is, in fact, a 5S rRNA encoded by the A. castellanii mitochondrial genome. These results emphasize the need for caution when interpreting negative results that suggest the absence of 5S rRNA and/or a mitochondrial DNA-encoded 5S rRNA sequence in other (particularly protist) mitochondrial systems.
18 citations
TL;DR: In this paper, stable isotopic compositions of 41 sweeteners (syrups, honeys, and sugars) and 43 edible oils were determined to evaluate their potential as parameters for food authentication.
18 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