Tetracyclines bioactivity

All samples contained the metabolite 4-epi-tetracycline, and this was even more pronounced in the liquid manure. Under strong acidic conditions (pH < 2), tetracycline is metabolized to anhydro-tetracyclines, which are bioactive, whereas alkaline pH conditions (pH > 7.5) can favor the formation of isotetracyclines, which show almost no in vitro activity. Tetracycline can also undergo extensive photodecomposition, forming a variety of products (Oka et al., 1989 Peterson et al., 1993). 

In addition to the above examples, there are still a large number of bioactive natural products and various synthetic and semisynthetic enol-containing compounds that serve as potential and promising drugs for various therapeutic purposes such as the non-peptidyl HIV inhibitor Aptivus (tipranavir Section IV.1) and the third-generation tetracycline antibiotics (Section IV.H). The structure and function of the metal complexes of some... 

Preliminary studies using the IPPSF have shown that compounds such as the cancer chemotherapeutic agents cisplatin and carboplatin and the antibiotics tetracycline and doxycycline readily distribute into the skin following intravascular administration. Also, compounds such as parathion, 1-aminobenzo-triazole (ABT), and 25-hydroxyvitamin D are bioactivated in the skin following intravascular administration in the IPPSF. This demonstrates a role for the IPPSF as an ideal experimental model for studying the disposition of xenobiotics that are... 

Various parts of M. oleifera are identified for innumerable pharmacological properties viz. antimicrobial activity (12, 134). The juice from the leaves and stem bark of M. oleifera inhibit Staphylococcus aureus but not Escherichia coli (50). The fresh leaf juice inhibits the growth of pathogenic Pseudomonas aeruginosa and Staphylococcus aureus (21, 143). The bark extract possesses anti-fungal and anti-tubercular activity (50). Niaziridin rich fraction of M. oleifera pods enhances the bioactivity of commonly used antibiotics such as rifampicin, tetracycline and ampicillin against gram(+) and (-) bacteria (37). 

Periodontal regeneration with chitosan has been observed after the implantation of chitosan in one-wall alveolar bony defects in dogs [210]. In our investigation, chitosan was selected as the carrier for tetracycline, mainly because it can both carry and deliver the medication, but also because it has other useful bioactivities such as anti-inflammatory properties [211]. 

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