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The role of plant antioxidants as factors of civilization diseases prevention was described. The free-radical theory as a mechanism of action of antioxidants was mentioned. The main substances e.g. polyphenols including flavonoids, ascorbic acid, carotenoids and tocoferols were presented. Resveratrol of wine, as an example of possible health beneficial agent was stressed. On the other handsome doubts of beneficial effects of antioxidants e.g. beta-carotene, as supplement of diet, were mentioned. It is possible, that supplementation with flavonoids might create some health risk. But there was highlighted, that vegetables as a source of natural antioxidants are beneficial for health.

The method for determination of aflatoxin B1, B2, G1 i G2 in nuts, culinary spices, cereals and cereal products was described. To optimize the analytical procedure in several products, condition of proper extraction, clean-up, HPLC and detection were selected. After extraction by means of methanol and water (80+20 v/v) or (70+30 v/v), clean-up on IAC columns, HPLC on C18 columns--Nucleosil and Nova Pak with mobile phase-methanol, acetonitrile, water (20+20+60 v/v) was performed. For fluorometric detection at 362/430 nm, post-column derivatization of aflatoxin B1 and G1 with bromine was carried out. The mean recovery of the method depending on matrix and aflatoxin, was 52-102% at RSD% 0.2-8.3. LOD and LOQ, respectively were: 0.01 and 0.02 microg/kg for nuts and 0.05 and 0.1 microg/kg for culinary spices and cereal products. The concentrations of aflatoxins in 86 samples of foods from market were below the permissible maximum levels legally binding.

In this review the several data concerning phytotoxins as natural harmful substances of plants and phycotoxins--toxicants of algae were described. For example plants are source of pyrrolizidine alkaloids, glycoalkaloids, glucosinolates as well as glycosides, saponine and psolarens. Possible adverse effects of phytoestrogens as endocrine disruptors versus beneficial influence these substances on human organism were mentioned. About lectins as possible factors of some diseases was reported, as well as some proteins as allergens of soy and peanuts was mentioned. Accumulated by shellfish and fish the most important phycotoxins such as saxitoxin, okadaic acid, brevetoxins and ciguatoxins were described. Phycotoxins produced several poisoning symptoms. Microcystins and nodularin--cyanobacterial phycotoxins of freshwater, was mentioned. In conclusion, the need of limitation of permissible levels of some plant toxicants, development of analytical methods as well as knowledge of influence of some technological processes on toxic plant substances was highlighted. The importance of balanced diet as a tool of defense against plant toxicants was concluded.

The method of determination of ochratoxin A in some spices: coriander, cloves, ginger, paprika, black pepper was described. Depending on kind of matrix, extraction with metanol/water (80/20) or with solution of 1% NaHCO3 and several variants of clean-up on IAC columns were investigated. The most useful extraction solvent appeared water solution of 1% NaHCO3. In case of cloves only, none of the methods of extraction and clean-up variants was appropriate. The mean recovery of the method, dependent on kind of sample, was 61-82% and RSD% 1.4 and 7.8. The estimated LOD and LOQ were 0.02 and 0.06 microg/kg, respectively. In samples of spice used for method preparation, ochratoxin A was detected on the level 3.4-4.6 microg/kg.

In this review the several data concerning food authenticity were presented. Typical examples of food adulteration were described. The most known are adulteration of vegetable and fruit products, adulteration of wine, honeys, olive oil etc. The modern analytical techniques for detection of food adulteration were discussed. Among physicochemical methods isotopic techniques (SCIRA, IRMS, SNIF-NMR) were cited. The main spectral methods are: IACPAES, PyMs, FTIR, NIR. The chromatographic techniques (GC, HPLC, HPAEC, HPTLC) with several kinds of detectors were described and the ELISA and PCR techniques are mentioned, too. The role of chemometrics as a way of several analytical data processing was highlighted. It was pointed out at the necessity of more rigorous control of food to support of all activity in area of fight with fraud in food industry.

The method for ochratoxin A determination in cereals (wheat, rye) was described. Application of immunoaffinity columns (IAC) for clean-up of extracts was investigated. The ochratoxin A content was determined by high-performance liquid chromatography using C18 column and fluorimetric detection at 330 nm (excitation) and 460 nm (emission). The mean recovery of ochratoxin A was 65-78%. The limits of detection (LOD) and quantification (LOQ) were 0.015 and 0.025 microg/kg, respectively. The positive results were confirmed by reaction with BF3 complex in methanol.

Ochratoxin A from wheat and rye grain was extracted with acetonitrile:water (60:40). After clean-up of extracts using immunoaffinity columns (IAC), ochratoxin was determined by high-performance liquid chromatography using C18 column and fluorometric detection at 330 nm excitation and 460 nm emission. The mean recovery of ochratoxin A at fortification levels 0.1-100 microg/kg, was 74-89%. The limits of detection (LOD) and quantification (LOQ) were 0.015 and 0.025 microg/kg, respectively. The positive results were confirmed by reaction with BF3 complex in methanol.

In 1990-2000 selected Polish cereals, cereal products and some different commodities collected in several regions of Poland were analysed for ochratoxin A (OTA) and aflatoxins. The frequency and the level of contamination of Polish cereals and cereal products by ochratoxin A seem to be similar as in most European countries. Aflatoxins in cereals and their products does not seem to be a problem in Poland, however the attention should be pay to some imported products like peanuts.

A simple method was described to determine vitamins B1 and B2 in fruit and vegetable-fruit juices. Vitamins were extracted with perchloric acid and for their determination an ion pairing RP-HPLC technique with UV detection by 254 nm was applied. The average recovery for vitamin B1 was 85-104% and 94-105% for vitamin B2. The statistically estimated limits of identification and detection were respectively, for both vitamins: for B1: 0.008 and 0.0024, and for B2 0.0002 and 0.0007 mg/ml of product.

A simple method was described to determine vitamin C as L-ascorbic acid (after reduction of dehydroascorbic acid by means of dithiothreitol) in fruit juices, fruit and vegetable-fruit nectars. Ascorbic acid was analyzed by RP-HPLC technique with UV detection (254 nm). The average recovery of ascorbic acid was 92-103% and limits of identification and detection were 0.003 and 0.009 mg/ml of products respectively.

The aim of this study was to perform a optimized method for determination of aflatoxin M1 in milk. The manner of extraction and clean-up of milk extracts as well conditions of reaction of aflatoxin M1 with TFA and HPLC was described. The main steps of optimized method were: extraction of samples with chloroform, clean-up of extracts on SPE C18 columns and by means of extraction with n-hexane, derivatisation of aflatoxin M1 with TFA (60 degrees C, 6 minutes) to acetal form--aflatoxin M2a and determination of aflatoxin by means of the RP-HPLC technique. The mobile phase was a mixture of methanol, isopropanol and water (18 + 7 + 75). Fluorometric detection was made at 370/418-700 nm. The mean recovery of aflatoxin M1 dependent on fortification level was 62-67%, limit of detection was 0.01 microgram/1 of milk.

The aim of this study was to perform a optimised method for determination of fumonisins B1 and B2 in corn products. The manner of extraction and clean-up of corn products extracts as well conditions of reaction of fumonisins with OPA was described. The main steps of optimised analytical procedure were: extraction of sample with methanol and water (3 + 1), clean-up of extracts on SAX column, derivatisation with OPA, and determination by means of RP-HPLC. The mobile phase was a mixture of methanol, water and acetic acid (75 + 24 + 1). Fluorometric detection was made at 370/440 nm. The mean recovery of fumonisins dependent on fortification level and product was 64-95%, limit of detection for each of fumonisins was 15 micrograms/kg.

A liquid chromatographic method for the determination of the intense sweeteners--aspartame and acesulfam-K in fruit and vegetable nectars was described. Samples were extracted with water, then clarified with Carrez solutions. An aliquot of the extract was analyzed on C-18 reverse-phase column with UV detection. Mean recoveries ranged from 95.9 to 101.8%. The method is suitable for routine determinations of both sweeteners.

A simple method for the detection and semiquantitative determination of zearalenone in enzyme preparations was described. The method comprises extraction with chloroform and acetone (80 + 20), mini-column chromatographic purification of the crude extracts on silicagel, and two-dimensional thin-layer chromatography. The mean recovery by this method in from 74 to 80% and detectability of zearalenone is 50 micrograms/kg.

A simple method for the detection and semiquantitative determination of sterigmatocystin in enzyme preparations was described. The method comprises extraction with acetonitrile and a 4% aqueous KCL solution, column chromatographic purification of the crude extracts on silica gel, and two-dimensional thin-layer chromatography. The mean recovery by this method is from 71 to 79%, and the detectability of sterigmatocystin is 20 micrograms/kg.

A simple method for detection and semiquantitative determination of aflatoxins B1, B2, G1 and G2 in enzymatic preparations is described. The method is based on extraction with a mixture of acetone with water, purification of extracts with lead acetate and on a column with aluminum oxide. The concentrated extracts were analysed by means of two-direction thin-layer chromatography. The mean recovery by this method was from 57 to 78% depending on the type of aflatoxin. The detection limit by this method was about 1 mcg/kg.

A simple method is described of identification and determination of deoxynivalenol (DON), nivalenol (NIV), diacetoxyscirpenol (DAS) and T-2 toxin in cereals. Chloroform-ethanol extracts were purified in columns filled with active charcoal, aluminium oxide and celite and were analysed by the method of thin-layer chromatography. The results were evaluated exposing fluorescent trichothecene derivatives to ultraviolet light, after they had been obtained on a chromatographic plate with aluminium chloride and sulphuric acid. The detectability of the method for various toxins was: DON--37, NIV--100, DAS--50, and T-2 toxin--100 mcg/kg.