Biological activities anti-bacterial

The diterpenoids of Isodon (Labiatae) species have been reviewed. The presence of an a-methylenecyclopentanone moiety in these diterpenoids is important for their anti-tumour and anti-bacterial activity. " Inflexin (79) is a cytotoxin and insect antifeedant which has been isolated from Isodon inflexus. Isodomedin (80) is another member of this series, isolated from /. shikokianus, which shows this type of biological activity. Its structure was assigned on the basis of its H and C n.m.r. spectra and on an interrelationship with kamebanin (81), isolated from /. kameba. 

Schmidt, D. R. and A. E. Sobota. 1988. An examination of the anti-adherence activity of cranberry juice on urinary and nonurinary bacterial isolates. Microbios 55 173-181. Gabius, H. J. and S. Gabius. 1998. Phytotherapeutic immunomodulation as a treatment modality in oncology lessons from research with mistletoe. In Lawsib, L. D. and R. Bauer (eds.). Phytomedicines of Europe, Chemistry and Biological Activity. American Chemical Society. Washington, D.C. p. 278-286. 

The anti-bacterial activity of the penicillins stimulated a major search for other antibiotics. Many compounds were isolated from amongst the metabolites of Streptomycetes obtained from soil. These included therapeutically useful antibiotics such as chloramphenicol, the tetracyclines, erythromycin and streptomycin. Several fungi yielded useful compounds. One of these was Cephalosporium acremonium. A biologically-active strain was obtained by Brotzu from a sewage outfall near Cagliari in Sardinia in 1945 and described in 1946. The p-lactam cephalosporin C (1.23) was isolated from this organism in 1954 and its structure determined in 1961 by Abraham and Newton. 

The most commonly reported biological activity for proteins derived from natural products is anti-bacterial activity. It appears as if every living organism has developed some mechanism by which to prevent infection by or direct competition with bacteria, including other bacteria. One such... 

This survey has also demonstrated that compounds isolated from a number of plants of this family possess a broad spectrum of biological activities such as cytotoxic, anti-fungal, anti-bacterial, anti-malarial, anthelmintic, anti-hepatotoxic, anti-oxidative, anti-ulcer, anti-inflammatory and hypothermic, hypolipimenic, hypotensive and spasmolytic activities. Insecticidal, molluscicidal, nematocidal and larvicidal activities are also... 

Many plant phenolics are of pharmaceutical interest. Flavonoids, lignans, flavolignans, coumarins, phenyl pro-panoids, and other phenolic compounds show a wide variety of biological and pharmacological activities, such as anti-oxidant, anti-hepatotoxic, spasmolytic, cytotoxic, anti-fungal, and anti-bacterial. Some flavonoids improve capillary resistance while isoflavonoids found in soy and other legumes have estrogenic activity. 

Sesquiterpenoids have been related with medicinal plants with different health applications, mainly anti-inflammatory [87], anti-HIV [88], antibacterial [89], and antitumor activity [88]. Up to date, no study has covered the biological activity of sesquiterpenoids from Vitis vinifera L grsLpes. Sesquiterpenoids such as famesol and nerolidol have been reported to have the ability to enhance bacterial permeability and susceptibility to exogenous antimicrobial compounds. These compounds increase the susceptibility of Staphylococcus aureus and Escherichia coli to antibiotics by disrupting the normal barrier function of the bacterial ceU membrane, allowing permeation into the cell of exogenous solutes such as antibiotics [90]. 

During the last decades compounds of the fluoroquinolone family proved to be not only effective inhibitors of bacterial enzymes their antineoplastic [287], antiviral [41] (including concerning HIV [288]), anti-diabetic [289] and other types [290, 291] of biological activity have been intensively elucidated. 

Heterocyclic Steroids - Much synthetic work continues to be published in this area. Two non-basic aza steroids, 13-aza-17-ketones, were prepared with the stated purpose of testing a hypothesis that the usual lack of hormonal activity of azasteroids is due to an Inability of basic steroids to penetrate cell membranes. However, no biological information was given.Some 15-aza-, 15,l6-diaza-, and 11,15,16-triazasterolds ° were synthesized. The former two types are reported to have anti-bacterial activity, whereas 17a-aza-0-homosteroids are inactive.The acetylation of one inactive 173-hydroxy-4-azasteroid was shown to confer anti-bacterial activity to the compound, but this effect was not general. The syntheses of a 5,10-diazasterold and of an A,B-indolo-steroid (14) were also reported. The successful preparations of 2-oxa,... 

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