In Vitro Bioaccessibility of Selenium from Commonly Consumed Fish in Thailand

Abstract

Selenium (Se), abundantly obtained in fish, is a crucial trace element for human health. Since there are no data on Se bioaccessibility from commonly consumed fish in Thailand, this study assessed the in vitro bioaccessibility of Se using the equilibrium dialyzability method. The five fish species most commonly consumed in Thailand were selected to determine total Se content using several preparation methods (fresh, boiling, and frying). Equilibrium dialyzability was used to perform in vitro bioaccessibility using enzymatic treatment to simulate gastrointestinal digestion for all boiled and fried fish as well as measuring Se using inductively coupled plasma triple quadrupole mass spectrometry (ICP-QQQ-MS). Two-way ANOVA with interaction followed by Tukey’s honestly significant difference (HSD) post hoc test revealed that boiled Indo-Pacific Spanish mackerel, longtail tuna, and short-bodied mackerel were significantly higher in Se content than striped snakehead and giant sea perch (p < 0.05). For fried fish, longtail tuna showed the highest Se content (262.4 µg/100 g of product) and was significantly different compared to the other fish (p < 0.05, estimated marginal means was 43.8–115.6 µg/100 g of product). Se bioaccessibilities from striped snakehead (70.0%) and Indo-Pacific Spanish mackerel (64.6%) were significantly higher than for longtail tuna (p < 0.05). No significant difference in bioaccessibility was found in terms of preparation method (i.e., boiling and frying). In conclusion, the fish included in this study, either boiled or fried, have high Se content and are good sources of Se due to high bioaccessibility.

In Vitro Evaluation of Bioavailability of Se from Daily Food Rations and Dietary Supplements

“…The determined bioavailability of Se was 80% from sardine, 76% from swordfish and 50% from tuna. Similar results were obtained by Singhato et al [ 32 ] who determined the bioavailability of Se from various fish commonly consumed in Thailand, which was 58.8% for boiled and 51.1% for fried fish. No influence of the cooking practice on the bioavailability of Se was revealed.…”

“…In contrast, high Se intake (mostly through excessive supplementation) may cause severe intoxication; thus, the amount which is consumed with food and dietary supplements should be strictly controlled [ 22 ]. Se enters the body only through the diet, and the amount which is available to the organism is correlated to the dose and chemical form in which the element is consumed [ 22 , 31 , 32 ]. Recent studies revealed that Se intake in Poland varies within a wide range from 36.9 to 106 and from 64.7 to 119 µg/day among women and men, respectively [ 5 , 6 ].…”

“…Se in food products is present in a variety of chemical forms, which in general are divided into organic and inorganic [ 32 ]. There are data indicating that, depending on the type of a food product, there is a predominance of a specific form of this element.…”

“…The biochemical properties of selenite and selenate are different, including their toxicity and energy consumption during uptake and metabolism [ 37 , 38 ]. In general, organic forms of Se are considered more effective for increasing endogenous human and animal levels and less toxic than inorganic forms of Se [ 32 , 37 , 39 ]. Both the organic and inorganic forms of the element are widely used in the form of dietary supplements and other nutritional sources of Se, such as functional foods, but they are all toxic in higher doses; thus, the intake of Se should be strictly monitored [ 37 ].…”

“…The bioavailability of Se depends on the type of food product and the method of thermal processing of food. Fish are considered a very good dietary source of Se because the content of the element and its bioavailability from these products are very high [ 32 ]. Cabanero et al [ 41 ] investigated the bioavailability of Se from commonly consumed fish in Europe using an in vitro method.…”