Natural drugs contamination

The polymicrobic nature of contaminating flora makes the use of wide-spectrum antibiotics mandatory [19, 20], The choice of the drug is frequently empirical because small bowel aspiration and culture are impractical and, if performed, will show with certainty multiple organisms with different antibiotic sensitivity. However, the reason why we need to use wide-spectrum antibiotics lies on a still lacking information we do not know which organisms should be eliminated to achieve the improvement of symptoms [19]. Several antibiotics have been shown to be effective (table 3). However, as can be clearly seen from this table, available data are based very frequently on the... 

The influence of diet on drug metabolism, disposition, and toxicity consists of many constituent factors. Food additives and naturally occurring contaminants in food may influence the activities of various enzymes by induction or inhibition. However, these factors are discussed in a later section Enzyme induction and Inhibition. The factors with which this section will be concerned are the nutritional aspects of diet. 

Even natural drugs are suspect on the black market. Marijuana m ay be laced with PCP or contaminated with paraquat. "Magic mushrooms" may be very ordinary mushrooms sprayed with LSD or PCP, and even if they are the genuine article, it is impossible to know how potent they are. 

Many authors reported poor elimination of antiepileptic drug carbamazepine [6,13,17,49, 54]. Pharmacokinetic data indicate that only 1-2% of carbamazepine is excreted unmetabolized. However, glucuronide conjugates of carbamazepine can presumably be cleaved in the sewage, and thus increase its environmental concentrations [51]. This is confirmed by its high ubiquity in the enviromnent at concentration levels of several hundred nanograms per liter in different surface waters. Due to its recalcitrant nature, it can be used as anthropogeiuc marker for the contamination of aquatic environment. 

It has been known for many years that microbial contaminants may effect the spoilage of pharmaceutical products through chemical, ply sical or aesthetic changes in the nature of the product, thereby rendering it unfit for use (see Chapter 18). Active drug constituents may be metabolized to less potent or chemically inactive forms. Physical changes commonly seen are the breakdown of emulsions, visible surface growth on solids and the formahon of slimes, pellicles or sediments in hquids, sometimes... 

The first linkage between a microscope and an IR spectrophotometer was reported in 1949 [15]. Today, every manufacturer of IR spectrophotometers offers an optical/IR microscope sampling accessory. The use of optical and IR microscopy is a natural course of action for any solid state investigation. Optical microscopy provides significant information about a sample, such as its crystalline or amorphous nature, particle morphology, and size. Interfacing the microscope to an IR spectrophotometer ultimately provides unequivocal identification of one particular crystallite. Hence, we have the tremendous benefit of IR microscopy for the identification of particulate contamination in bulk or formulated drug products. 

To date, most approved protein-based drugs are for therapeutic or replacement therapies. They are recombinant versions of natural proteins such as insulin and erythropoietin. Their characteristics and functions are relatively well defined and known. The next phase of biopharmaceuticals, such as antibodies and vaccines, is more complex and requires more tests and characterizations. Controls for the reliability, contamination, and fidelity of expression systems will be high on the agenda in the coming decade. 

As liquid chromatography plays a dominant role in chemical separations, advancements in the field of LC-NMR and the availability of commercial LC-NMR instrumentation in several formats has contributed to the widespread acceptance of hyphenated NMR techniques. The different methods for sampling and data acquisition, as well as selected applications will be discussed in this section. LC-NMR has found a wide range of applications including structure elucidation of natural products, studies of drug metabolism, transformation of environmental contaminants, structure determination of pharmaceutical impurities, and analysis of biofiuids such as urine and blood plasma. Readers interested in an in-depth treatment of this topic are referred to the recent book on this subject [25]. 

The Joint FAO/WHO Expert Committee on Food Addihves (JECFA) is an international expert scientihc committee that is administered jointly by FAO and WHO. It has been meeting regularly since 1956, inihally to evaluate the safety of food addihves. Its work now also includes the evaluation of contaminants, naturally occurring toxicants, and residues of veterinary drugs in food. These evaluations are collected in a report published after each JECFA meeting (Section 3.6.1.3) (JECFA 2006). 

Toxicological evaluations of food additives and of contaminants, naturally occurring toxicants and residues of veterinary drugs in food produced by the Joint FAO/WHO Expert Committee on Food Additives (JECFA), and of pesticide residues in food by the Joint FAO/WHO Meeting on Pesticide Residues (JMPR) are used by the Codex Alimentarius Commission and national governments to set international food standards and safe levels for protection of the consumer. 

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