The changing diameter of the moon was 3 caused by the intersection of the optical mechanism with the rays of light. The deception detected by Brahe, Kepler Figure 3. Johannes Kepler It was this thesis that transformed the camera obscura from a mere instrument into a scientific object and other picturesque sites, produced an image on a of inquiry in its own right.
It is true that scientists are table. A second type was in the form of a portable tent: often so taken with instruments that their interest in featuring a lens and mirror at the apex of the tent, it them transcends any connection with theory. Though produced an image on a horizontal desk inside. The instruments may come to enjoy a great deal of autono- third form was the portable box camera obscura that my from theoretical concerns, their value as instru- produced an image on light-sensitive material.
It was ments is frequently tied to their ability to generate use- this type of camera obscura that eventually lead to the ful measurements. With Kepler's pioneering work in development of the photographic camera. A n unpalatable consequence of Kepler's hypothesis was that naked-eye observation was somehow superior to instrument-mediated observation. This consequence was congenial to the Scholastic natural philosophy that dominated intellectual life in and around the universities.
A central doc- trine of Scholastic accounts of knowl- edge was that there is nothing in the mind which is not first in the senses. Equivocating the scientific with the sensible, these same scholars would soon oppose Galileo's startling tele- scopic observations with the common sense refrain that such things as Jupiter's moons and the craters of the moon are not available in ordinary Figure 4.
A print from Frank Leslie's Popular Monthly showing a scene inside sensation and so must be artifacts of the Central Park camera obscura. Photo courtesy of Jack and Beverly Wilgus of Galileo's instrument. Anticipating this Bright Bytes Studio. Seventeenth Century. Chicago: The University of Chicago Press. Kepler's demonstration that the human eye is a modified camera obscura—a picture-making machine—changed the practice of science forever. Mechanical analogy, and the mechanical models that are generated by analogous reasoning, are among the handful of tools in the scientist's toolkit.
Kepler's demonstration was the first concrete scientific realiza- tion of an analogy between things that exist in a pure state of nature and mechanical contrivances fashioned by hammer and tongs. The mechanization of the human eye proved to be the first in a long series of mechanical analogies that fill the pages of the sciences of the early modern peri- od.
In short order, the English anatomist William Harvey argued that the heart is a mechanical pump, the principal function of which is Figure 5. Illustration of the eyes of a grey drone fly, which to violently propel blood into the arterial system. The objection, Kepler fatally undermined the Scholastic French natural philosopher Rene Descartes account of knowledge and the authority traditionally took the additional step, in a number of conferred on ordinary vision by pointing out that scientific treatises, of treating the entire living animal deception is also built into the human eye, which, he body as an inanimate machine.
Various extracts of Ipomoea obscura have been reported to possess anti- inflammatory, nephroprotective, anti-angiogenic and immune modulatory activities Mungole et al. Previous studies in our laboratory have also shown that the whole plant extracts of Ipomoea obscura possess strong antioxidant activity against various free radicals Anokbonggo et al.
Plants belonging to Ipomoea species such as Ipomoea aquatica and Ipomoea batatas [L. However, there is no cytotoxic and antimicrobial activities are reported for Ipomoea obscura L.
Hence, in the present investigation different extracts of Ipomoea obscura L. Collection of plant material: A whole plant of Ipomoea obscura L. Corresponding Author: Srinivasan, R. Extraction: The whole plant material was dried in shade.
The dried plant material was powdered and passed through sieve no. The extracts were concentrated to dryness under reduced pressure and controlled temperature 40 — 50oC. The petroleum ether extract yielded a yellowish green sticky semisolid, weighing 1. The methanol and water extracts yielded dark green and dark brown semisolid residues, weighing Three normal cell cultures cells Vero-African green monkey kidney, BRL-3A-normal rat liver and MDCK-normal dog kidney and three cancerous cell lines e HeLa-human cervical cancer cells, HEphuman larynx epithelial cancer cells and Ahuman small cell lung carcinoma cells were used to determine cytotoxicity.
All tests and analysis were run in triplicate and mean values recorded. College of Pharmacy, Ooty. Antimicrobial assay: Cup plate method using Mueller-Hinton agar medium was employed to study the preliminary antibacterial activity of various extracts of Ipomoea obscura Alviano and Alviano, College of Pharmacy, Ooty, India.
The diameter of inhibition zones was measured in mm and the results were recorded. The inhibition zones with diameter less than 12 mm were considered as having no antibacterial activity. The results of the in vitro cytotoxicity studies on successive extracts of Ipomoea obscura reveal that the methanol extract has better cytotoxic nature over the other two extracts water and petroleum ether with CTC50 values ranging from The water extract exhibits moderate cytotoxicity against all the cell lines with CTC50 values ranging from The petroleum ether extract is nontoxic at test doses against all the cell lines.
Among the three extracts tested, the methanol extract shows lesser toxicity towards normal cell lines such as Vero, BRL-3 A and MDCK when compared to cancerous cell lines.
Hence, the methanol extract shows moderate specificity against cancer cell lines. All the three extracts showed moderate antibacterial and antifungal activity against the six microbial strains tested. The possible antimicrobial mode of action of Ipomoea obscura is probably because of its ability to bind to the cell wall, thereby inhibiting its synthesis due to the presence of alkaloids. Plants are promising source of anti-infective and anticancer chemotherapeutic agents Bhahwal et al.
Since India has a broad medicinal plant diversity and Ipomoea obscura is also one of the most commonly used plants in India to cure many diseases Sripathi and Sankari, The Ipomoea obscura contains major pharmacologically active macrolactum type indole alkaloids such as ipobscurine-A, C and D. These indole alkaloids were reported to possess strong anti-inflammatory and anti-angiogenic properties Hamsa and Kuttan, In summary, the present study demonstrated that the successive methanol extract of Ipomoea obscura has shown good cytotoxic and moderate antibacterial activities.
The possible mechanism involved in the cytotoxicity may be due to the induction of apoptosis pathways by indole alkaloids. These results indicate that Ipomoea obscura phytochemicals have distinct potentials for chemoprevention and chemotherapy strategies.
However, further studies are required to isolate the active compounds and to determine the detailed and distinguishing features of intracellular pathway s involved in the mechanism of cytotoxicity. Test microorganism Diameter of zone of inhibition mm Petroleum ether Methanol extract Water extract Standard antibiotic extract Escherichia coli Alviano, Current Pharmaceutical Biotechnology, 10 1 : Anokbonggo, W. Odoi-Adome and P. Oluju, Traditional methods in management of diarrhoeal diseases in Uganda.
Bulletin of the World Health Organization, 68 3 : Asano, N. Yokoyama, M. Sakurai, K. Ikeda and H. Kizu, Need an account? Click here to sign up. Download Free PDF.
Methoxyflavones from Melicope borbonica and M. Henrik Toft Simonsen. Ulla Smitt. Dominique Strasberg. A short summary of this paper.
Download Download PDF. Translate PDF. Biochemical Systematics and Ecology 31 — www. Subjects and source Leaves of Melicope borbonica Bory T. Hartley syn. Euodia borbonica var. Leaves of Melicope obscura Cordem. Euodia obscura Cordem. E-mail address: uws dfh. All rights reserved. Simonsen et al. Coumarins and furanocoumarins are widespread in the family Rutaceae and occur in Euodia, Melicope and Tetradium Hegnauer, Therefore, their chemotaxonomic significance is limited.
Methylendioxyflavones and methoxyfla- vones have been isolated from M. Highly methoxylated flavones and especially methylendioxyflavones are characteristic for the genus Melicope.
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