Development of a Cost-Effective Method for Nitrate and Nitrite Determination in Leafy Plants and Nitrate and Nitrite Contents of Some Green Leafy Vegetables Grown in the Aegean Region of Turkey

Abstract

An accurate, fast, easily applicable, and cost-effective method for the determination of nitrate and nitrite was developed. This method was much more reliable than the cadmium column reduction method, which is a tedious and time-consuming procedure and not easily applicable. The principle of the method was reduction of nitrate to nitrite with cadmium acetate solution and zinc powder and then treatment with Griess reagent. Recovery of the method changed from 92.9 to 102.8%, and detection limit was found as 31.4 mg/kg. Coefficient of variation was 3.16% for intraday precision. Nitrate and nitrite contents of 10 types of leafy vegetables native to the Aegean region of Turkey were determined. Wild radish, chicory, fennel, blessed thistle, blue mallow, and chard were analyzed for the first time. Nitrate contents were found between 354.8 mg/kg for iceberg lettuce and 4653 mg/kg for wild radish. Tested vegetables contained <26.33 mg/kg nitrite.

Study of nitrate levels in fruits and vegetables to assess the potential health risks in Bangladesh

“…They react with the secondary amines in the stomach and lead to the formation of nitrosamines (N-nitroso compounds), some of which are known to be carcinogenic, teratogenic, and mutagenic. This increases the risk of cancer to the stomach and esophagus [6][7][8][9] . Some studies have evidence that a positive correlation exists between high nitrate consumption and gastric cancer in humans 10,11 .…”

Mediterranean diet and cardioprotection: The role of nitrite, polyunsaturated fatty acids, and polyphenols

“…The largest dietary sources of NO 3 − for the human body include green vegetables such as spinach, lettuce, and collard greens and also radishes, beets [18,19], and meat [20]. Furthermore, NO 2 − itself can be found in cured meats [21].…”

A Simple Electrochemical Method for Nitrate Determination in Leafy Vegetables

“…The most sensitive method for nitrite and nitrate determination is chemiluminescence detection, which can determine as low as 0.1 μM nitrate in some samples, however it requires special and expensive instru-mentation, nitric oxide analyzer chemiluminescence detector [11,12]. Other methods for determining nitrate include the reduction of nitrate to nitrite either with a cadmium solution or passage through a copper-coated cadmium column followed by nitrite measurement by the well-known Griess assay [12][13][14].…”