Biogenic amines limits

A new cyanide dye for derivatizing thiols has been reported (65). This thiol label can be used with a visible diode laser and provide a detection limit of 8 X 10 M of the tested thiol. A highly sensitive laser-induced fluorescence detector for analysis of biogenic amines has been developed that employs a He—Cd laser (66). The amines are derivatized by naphthalenedicarboxaldehyde in the presence of cyanide ion to produce a cyanobenz[ isoindole which absorbs radiation at the output of He—Cd laser (441.6 nm). Optimization of the detection system yielded a detection limit of 2 x 10 M. 

Fluorescence detection, alone or with the aid of derivatizing reagents to enhance detector responses and improve the chromatographic resolution, has also been used for the determination of biogenic amines. Lakshmana and Trichur (1997) used native fluorescence to analyze NE, DA, and 5HT in rat brain utilizing an isocratic separation on an ODS CIS column. The detection limits reported were 100-250 pg on column. 

As outlined previously, initial biological hypotheses of mood disorders were derived from the pharmacological actions of antidepressant drugs, which increase synaptic concentrations of noradrenaline (NA] and/or serotonin. Consequently, the biogenic amine hypothesis was formulated, but it lacks consistent proof that NA and/or serotonin release is indeed diminished. This failure is in part a result of the limited access to relevant brain areas. Measurements of NA and serotonin and their metabolites in blood, urine, and CSF... 

Biogenic amines can be found in processed meat products as a consequence of microbial activity related to the fermentation involved in their processing, but amines can be also found in poor-quality raw materials as a consequence of microbial contamination. Therefore the BA content in cooked meat (not fermented) products might serve as a useful indicator of the hygienic quality of the meat employed for its elaboration. However, this relationship for ripened meat products is rather complex, since the ability to produce BAs of the fermentative microflora need to be well known before limits can be set. According to the few studies performed on BAs in meat products,... 

The conversion of several biogenic amines into their acetyl derivatives has been attempted [26] for their analysis by HPLC with UV detection. The calibration graphs are linear within the tested range and the limits of detection range from 30 to 250 ng depending on the amine. 

The use of fiuorescamine for the analysis of primary amines has been discussed for amino acids and biogenic amines. The reaction of this compound with amphetamine analogues is similar. The spray procedure is identical to that described for primary amino acids (Section 4.2.1.1.3). The limit of detection is 100 ng for amphetamine [84]. 

A separate vein of examples worthy of investigation can be found in a surprising location - pharmaceutical chemistry. In fact, this field abounds with aminoalkyl aromatic systems of varied structure. At least one reason for this wealth is that biogenic amines are of this structural type and serve as a continuing inspiration for the drug discovery effort. An early example is (43), first described in 1951 as a prospective antimalarial [101]. (43) has been found in our laboratory to display pH sensitive fluorescence [102] as expected of a PET sensor. The spacer of three carbon atoms limits the PET rate in the proton-free form which leads to a modest but useful proton-induced fluorescence enhancement. The fluorescence properties of another antimalarial (44) with structural features required of a PET sensor have been recently reported in a different context [103] and deserves sensory evaluation. 

The central composite design was often selected because of the limited number of experiments needed to sample the response surfaces. In the separation of As and Se species in tap water, the analysis of isoresponse curves allowed the determination of optimum chromatographic conditions and the robustness of the method [77]. The same design was also used to study the influence of an organic modifier and IPR concentration on retention of biogenic amines in wines. To obtain a compromise between resolution and chromatographic time, optimization through a multi-criteria approach was followed [78]. 

The various contaminations in foods are due to the presence of compounds dangerous for consumer health or that affect organoleptic characteristics of the product. Ochratoxin A (OTA) and biogenic amines are dangerous for human health, and their legal limits are fixed in grape and wine. Due to their negative sensory properties and very low sensory thresholds, 2,4,6-trichloroanisole and ethylphenols have to be practically absent in wine, or present at as low a level as is possible. 

Biogenic amines are dangerous to human health and legal limits are fixed in grape and wine (structures are reported in Fig. 8.13). These compounds were found in fermented foods and beverages, such as cheeses, beer and fish, and meat products (Stratton et al., 1991 Shalaby, 1996). In wine, the most abundant are histamine, tyramine, putrescine, and phenylethylamine (Radler and Fath, 1991 Lehtonen, 1996). 

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