29 research outputs found
Antimicrobial activity of plant phenols from Chlorophora excelsa and Virgilia oroboides
The anti-bacterial and anti-fungal activity of four aqueous plant extracts (1 x 104 μg/ml) of 2,3'4,5'-tetra hydroxy-4'-geranylstilbene (chlorophorin) and 3',4, 5' - trihydroxy - 4' - geranylstilbene (Iroko) from the tree Chlorophora excelsa and (6aR,11aR)-3-hydroxy-8,9-methylenedioxypterocarpan (Maackiain) and 7-hydroxy-4'-methoxyisoflavone (formononetin) from Virgilia oroboides were evaluated by the seeded agar overlay well diffusion method. The test organisms and bioautography used included: Bacillus coagulans, Streptococcus pneumoniae, Klebsiella pneumoniae, Escherichia coli, Mycobacteria tuberculosis, Aspergillus flavus and Fusarium verticilloides. Vancomycin, the drug of choice for these organisms was used as the control at 30 μg/ml. The extracts showed that chlorophorin at 1.95 μg/ml and Iroko at 3.125 and 6.25 μg/ml respectively were active in inhibiting the growth of S. pneumoniae and B. coagulans and not active against K. pneumoniae and E. coli. Maackiain; formononetin and formononetin acetate showed little activity against S. pneumonia, B. coagulans, K. pneumoniae and E. coli. None of the extracts showed activity against M. tuberculosis. Maackiain, formononetin, chlorophorin and Iroko inhibited F. vertiicilloides, maackiain being the most active compound. Formononetin, chlorophorin and Iroko inhibited A. flavus. A. flavus was most sensitive to chlorophorin and Iroko. The bioautography method confirmed these results and was attributed to the phenolic nature of the compounds.Keywords: Plant compounds, anti-bacterial, anti-fungal, chlorophorin, IrokoAfrican Journal of Biotechnology Vol. 12(17), pp. 2254-226
Chemical constituents of the essential oil from Syzygium cordatum (Myrtaceae)
Essential oil was extracted from dried leaves of Syzygium cordatum by hydrodistillation. The components were identified by gas chromatography (GC/FID) and gas chromatography coupled with mass spectrometry (GC/MS). Sixty compounds representing 79% of the S. cordatum oil were identified. The main constituents were 6,10,14-trimethylpentadecane-2-one (14.4%), 2,3-butanediol diacetate (13.3%), n-hexadeconic acid (7.2%), ethane, 2-chloro-1,-bis(2 chloroethoxy) (6.2%), Isopentyloxyethyl acetate (5.03%), methane and bis (2-chloroethoxy) (3.8%).Keywords: Syzygium cordatum, essential oil composition, 6,10,14-trimethylpentadecane-2-one, 2, 3-butanediol diacetat
GENETIC TRANSFORMATION OF CERATOTHECA TRILOBA FOR THE PRODUCTION OF ANTHRAQUINONES FROM HAIRY ROOT CULTURES
Background: Ceratotheca triloba was found to contain three anthraquinones (9, 10-anthracenedione, 1-hydroxy-4-methylanthraquinone
and 5, 8-dimethoxy-2, 3, 10, 10a-tetrahydro-1H, 4aH-phenanthrene-4, 9-dione [DTP]) in its roots. Inhibition of the human topoisomerase
II enzyme is the basis of some currently used cancer drugs such as doxorubicin which is shown to be cardio-toxic. For this reason we
decided to investigate anthraquinones from C. triloba as a possible anticancer drug, however the main limitation was the large quantities
of roots that are required to obtain a good yield of the active compound. Therefore the aim of this research was to obtain a higher yield of
anthraquinones in hairy roots cultures than the parent plant as well as to compare yields of hairy root, cell suspension and shoot cultures.
Materials and Methods: Protocols for seed sterilization, seed germination, shoot cultivation, callus induction, A. rhizogenes mediatedtransformation
and hormone supplementations of hairy roots were developed.
Results:The results revealed that stem explants was susceptible to transformation by Agrobacterium rhizogenes at a low optical density
of 0.2. Induced hairy roots were decontaminated by exposure to cefotaxime at 500mg.l-1 for five days and then 200mg.l-1 for eight days.
Visualization of culture extract profiles by TLC revealed anthraquinones were present in all cultures. Analysis of the culture extracts by
HPLC showed the highest yield of anthraquinones was produced in hairy root cultures supplemented with 1-Naphthaleneacetic acid
[NAA] (8 mg). This was a 17 fold increase compared to field roots (0.47 mg).
Conclusion:Therefore C. triloba hairy root cultures are the preferable biological system for anthraquinones production over shoot (0.13
mg) and cell suspension cultures (0.70 mg)
Chemical composition of essential oil of Psidium cattleianum var. lucidum (Myrtaceae)
The aim of this study was to investigate the essential oil composition of Psidium cattleianum var. lucidum from South Africa. The essential oils were extracted by hydrodistillation and the components were identified by gas chromatography coupled to mass spectrometry (GC-MS) to determine the chemical composition of the essential oil. A total of 53 chemical components were identified, accounting for 61% of the essential oil. The major component was caryophyllene oxide (12.43%), while other predominant constituents were identified as bicyclo(4.4.0)dec-l-ene (6.61%), 2,3-butanediol diacetate (4.84%) and patchoulene (4.73%). The presence of many terpenic and ester compounds is thought to contribute to the unique flavor of the P. cattleianum var. lucidum leaves.Keywords: Psidium cattleianum var. lucidum, essential oil, hydrodistillation, caryophyllene oxid
Detection of Glutathione S-Transferase gene (GST2, GST3) during induction of somatic embryogenesis in grape (Vitis vinifera L.)
Glutathione S-transferases (GSTs) are an important group of multifunctional enzymes that belong to diverse multigene families. In plants these enzymes are involved in the detoxification of xenobiotic compounds, herbicide detoxification, and primary and secondary metaboplism and play an important role in plant growth and development. There are several reports that show that the expression of GST is linked to the developmental phases of somatic embryogenesis. This study highlights the detection of transcript abundances of glutathione S-transferase genes GST2 and GST3 in the process of somatic embryogenesis of Vitis vinifera, and the lack thereof in non-embryogenic tissue of leaf cultures of grape (control). These results indicate that the expression of GST2 and GST3 could be used as a molecular signal for the identification of embryogenic cultures during the early development of somatic embryos
Studies of Neisseria Gonorrhoeae.
Thesis (M.Sc.)-University of Durban-Westville, 1988.No abstract available.There is a concluding summary at the end
Methyl 4-(4-chlorophenyl)-8-iodo-2-methyl-6-oxo-1,6-dihydro-4H-pyrimido[2,1-b]quinazoline-3-carboxylate
In the title compound, C20H15ClIN3O3, the dihedral angle between the quinazolinone ring system [r.m.s. deviation = 0.047 (2) Å] and the pendant benzene ring is 82.63 (11)°. The molecular conformation is stabilized by intramolecular C—H...O interactions. In the crystal, the molecules are linked by N—H...O hydrogen bonds into chains along the a-axis direction. Another set of chains propagating along [101] is formed due to intermolecular I...Cl short contacts of 3.427 (1) Å, thus giving layers parallel to (010). The layers are connected by C—H...π and π–π interactions, the shortest distance between the centroids of aromatic rings being 3.8143 (16) Å
2-(4-Bromoanilino)-6-(4-chlorophenyl)-5-methoxycarbonyl-4-methyl-3,6-dihydropyrimidin-1-ium chloride
In the title molecular salt, C19H18BrClN3O2+·Cl−, the dihedral angles between the pyrimidine ring and the chlorobenzene and bromobenzene rings are 72.4 (2) and 45.5 (2)°, respectively. The dihedral angle between the chlorobenzene and bromobenzene rings is 27.5 (2)°. The conformation of the molecule is stabilized by an intramolecular C—H...O interaction. In the crystal, the anion and cation are linked by an N—H...Cl hydrogen bond. Pairs of weak C—H...O and C—H...Cl hydrogen bonds form inversion dimers. Further N—H...Cl hydrogen bonds form R21(6) motifs and link the dimers into chains along [101]. Br...Cl short contacts [3.482 (2) Å] interlink the hydrogen-bonded chains along the b-axis direction
Polymorphism in two biologically active dihydropyrimidinium hydrochloride derivatives: quantitative inputs towards the energetics associated with crystal packing
info:eu-repo/semantics/publishe
Screening of traditional South African leafy vegetables for specific anti-nutritional factors before and after processing
Abstract This study investigated the effect of processing on anti-nutritional factors of thirteen traditional leafy vegetables collected in Kwa Zulu-Natal, South Africa. The aim was to determine whether processing reduced anti-nutrient levels of leafy vegetables. The vegetables were boiled in a plant-to-distilled water ratio of 1:4 (w/v) at 97 °C for a time period of 5 and 15 min. The vegetables studied were: Amaranthus dubius, Amaranthus hybridus, Asystasia gangetica, Bidens pilosa, Ceratotheca triloba, Chenopodium album, Emex australis, Galinsoga parviflora, Guilleminea densa, Momordica balsamina, Oxygonum sinuatum, Physalis viscosa and Solanum nigrum. From this study, it was determined that non processed samples contained anti-nutrients such as tannins, phytic acid, alkaloids, oxalic acid, and cyanogenic glycoside. Both boiling parameters were effective in reducing the tannin, phytic acid, alkaloid, oxalic acid and cyanogenic glycoside contents of all 13 traditional leafy vegetables. The results of this study provide evidence that the local traditional leafy vegetables which the population is so reliant upon, are important contributors to micronutrient malnutrition in developing countries and can be minimized through common boiling methods for a minimum of 5 and maximum of 15 minutes