Selenium Concentrations of Selected Medicinal and Aromatic Plants in Turkey

Abstract

Recent scientific studies have proven the importance of trace elements on human health. The main food supplies are plants and animals, which are significant sources of these minerals. Studies on determining mineral compositions of herbs, spices and some other crops have increased all over the world. Published works revealed that spices, herbs and medicinal plants should be consumed to obtain beneficial trace elements. Selenium (Se), one of the most vital trace elements, has a significant role in human diet acting as a preventative agent against some serious illnesses. Despite numerous scientific works on mineral compositions of medicinal and aromatic plants, investigations of selenium content in these foods could not be successfully studied until recently due to the lack of suitable analytical methods for selenium analysis. Thus, publications on selenium concentrations of foods are recent. In this regard, selenium contents of some medicinal and aromatic plants commonly used as spices, herbal teas and traditional medicines in Turkey were studied in the present research. Selenium contents of the most used parts of these plants were analyzed by ICP-OES (Varian Vista-Pro, Australia). Of the analyzed 26 medicinal and aromatic plants, the highest Se concentration (1133 µg kg-1) was found in sweet basil (Ocimum basilicum L.) and the lowest in sumac (Rhus coriaria L.) fruits (11 µg kg-1).

Method development for the determination of elements in Hypericum perforatum L. (St John's wort) herb and preparations using inductively coupled plasma–optical emission spectroscopy and microwave digestion

“…The presence of silica in SJW samples may also affect the elements recovered . The majority of pre‐existing SJW studies [ ] often focus on five elements or less, while Bu et al . monitored 12 and our recent investigations found 15 elements in SJW preparations .…”

“…The presence of silica in SJW samples may also affect the elements recovered. [23] The majority of pre-existing SJW studies [13,15,22,[24][25][26][27][28][29] often focus on five elements or less, while Bu et al [20] monitored 12 and our recent investigations found 15 elements in SJW preparations. [3] Due to the lack of Certified Reference Materials (CRMs) available for SJW, a number of plant-based CRMs have been reported for accuracy assessments including tomato leaves, [18,20,30] peach leaves, [20] spinach leaves, [20] tea leaves, [3,9,19,31] mixed Polish herbs, [31] grass [32] and tobacco.…”

“…In previous studies, an external calibration method is usually indicated. [10][11][12][13][14][15][17][18][19][20][21][22]27,31,35,42] One study used standard addition for the analysis of Pb, [14] and a small number of studies used an internal standard, [12,19,20] often with ICP-MS.…”

Basil seeds as a source of antioxidants affected by fortification with selenium

“…After application of 5 mg Se ⋅ m -2 in two varieties of peas, 25-fold increase in the selenium content in seeds was reported in comparison with control in the study by Hegedűsová et al (2015). As lot of other crops such as peas, rice, corn, wheat (Gomez-Galera et al, 2010;Ozkutlu et al, 2011;Poblaciones et al, 2014;Premarathna et al, 2012;Manojlović et al, 2019;Hawkesford and Zhao, 2007;Poblaciones and Rengel, 2018;Fernandes et al, 2014) were positive in test for incorporation of selenium in grains, there was prediction of selenium increasing possibility in basil seeds. In selenised basil seeds, the increase in selenium content in case of Tulsi was 17-fold in comparison with control variant, 12-fold in 'Cimonette' and 12-fold in 'Dark Green' compared with control.…”

“…Since selenium (Se) plays a significant role in antioxidant defence, biofortification with Se is a good way to improve the nutritional quality of sprouts, microgreens (Puccinelli et al, 2019) and other kind of vegetable (Hegedűsová et al, 2015;Hegedűsová et al, 2017;Andrejiová et al, 2019;Smoleń et al, 2016). Se concentrations in plant-derived foods are highly variable due to the genetic variation for Se accumulation and environmental conditions (Ozkutlu et al, 2011). Based on positive basil herb reaction to biofortification with selenium (Hawrylak-Nowak, 2008;Mezeyová et al, 2016;Mezeyová et al, 2018), our research paper was aimed to clarify how the mechanism of selenium incorporation into the seeds will take place after foliar biofortification with the sodium selenate in selected varieties of the genus Ocimum spp.…”