FOLIA BIOLOGICA ET GEOLOGICA 58/2, 45–51, LJUBLJANA 2017
FAGOPYRIN AND RUTIN CONCENTRATION IN SEEDS OF 
COMMON BUCKWHEAT PLANTS TREATED WITH Se AND I
VSEBNOST FAGOPIRINA IN RUTINA V SEMENIH NAVADNE 
AJDE TRETIRANE S SELENOM IN JODOM
Mateja GERM1, Zlata LUTHAR1, Eva TAVČAR BENKOVIĆ2, Meiliang ZHOU3, Aleksandra 
GOLOB1 & Nina KACJAN MARŠIĆ1,*
http://dx.doi.org/10.3986/fbg0027
ABSTRACT
Fagopyrin and rutin concentration in seeds of common 
buckwheat plants treated with Se and I
Very little data about impact of simultaneous addition 
of selenium and iodine on plants exists. Plants of common 
buckwheat Fagopyrum esculentum Moench. were grown 
outdoors and were foliarly treated at the beginning of the 
flowering with different forms of Se (selenite, selenate) and I 
(iodide, iodate) and their combinations. Plants were harvest-
ed and seeds were collected and grounded, and the concen-
trations of fagopyrin and rutin were determined. Nor Se, nor 
I, alone or their combination had an influence on the con-
centration of fagopyrin. Selenium, iodine and their combi-
nation affected the amount of rutin in common buckwheat 
grain.
Key words: fagopyrin, rutin, common buckwheat, seeds, 
Se, I
IZVLEČEK
Vsebnost fagopirina in rutina v semenih navadne ajde tre-
tirane s selenom in jodom
Zelo malo je znanega o sočasnem vplivu elementov sele-
na in joda na rastline. Rastline navadne ajde (Fagopyrum 
esculentum Moench.) gojene na prostem, smo v začetku 
cvetenja tretirali z raztopinami selena (selenit, selenat) in 
joda (jodit, jodat) ter njihovimi kombinacijami. Zrnje treti-
ranih rastlin je bilo zmleto in izmerili smo koncentracije 
fagopirina in rutina. Na koncentracijo fagopirina v zrnju ni 
vplivalo niti tretiranje rastlin s selenom niti z jodom, pa tudi 
ne kombinacija obeh elementov. Na koncentracijo rutina v 
zrnju pa so značilno vplivala tako posamična tretiranja z 
raztopinami obeh elementov kot tudi kombinirano tretiran-
je.
Ključne besede: fagopirin, rutin, navadna ajda, semena, 
selen, jod
 1 Biotechnical Faculty, University of Ljubljana, 1000 Ljubljana, Slovenia, 
 2 Faculty of Pharmacy, University of Ljubljana, 1000 Ljubljana, Slovenia
 3 Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing, 100081, China. 
 * Corresponding author: nina.kacjan.marsic@bf.uni-lj.si
GERM, LUTHAR, TAVČAR BENKOVIĆ, ZHOU, GOLOB & KACJAN MARŠIĆ: FAGOPYRIN AND RUTIN CONCENTRATION
46 FOLIA BIOLOGICA ET GEOLOGICA 58/2 – 2017
Se and I are essential elements for proper function of 
human thyroid (Zimmermann & Köhrle 2002, 
White & Broadley 2009). Essentiality of Se and I for 
plants is still under debate. However, it has been evi-
denced that Se has many positive effects on plants, 
capable of accumulating this element (Golob et al. 
2016). Recently there were some reports about com-
bined effects of Se and I on plants (Zhu et al. 2004, 
Smoleń et al.  2014, 2016, Germ et al. 2015, Osmić et 
al. 2017, Jerše et al. 2017). However, according to our 
knowledge, the effect of Se and I on buckwheat grain 
has not been studied. Common buckwheat (Fago-
pyrum esculentum Moench) is a very important alter-
native crop in Europe due to possibility of its ecologi-
cal cultivation, furthermore, its use in the diet has 
many positive effects on health and nutritional status 
of consumers (Skrabanja et al. 1998, 2000, 2001, 
Kreft et al. 2002, Bonafaccia et al. 2003, Kreft 
2016). Buckwheat grain contain high amounts of 
rutin. The role of rutin is scavenging free radicals and 
anti-fungal activity (Suzuki et al. 2015). Besides f la-
vonoids, buckwheat also contains trace elements, like 
Zn, Cu, Mn and Se (Cuderman & Stibilj 2010). 
Buckwheat has many favourable medicinal properties 
for humans, because of its antioxidative (Holasová 
et al. 2002, Kreft 2016), anti-inflammatory and anti-
carcinogenic effects and it can also increase the 
strength of blood vessels (Brozmanová et al. 2010). 
Li & Zhang (2001) reported about significant health 
benefits of buckwheat for individuals with diabetes, 
obesity and constipation. Common buckwheat origi-
nates from Southwest China and it has been gradually 
spread to other continents (Kreft 1995). Buckwheat 
contains fagopyrins, phototoxic naphtodianthrones, 
similar to hypericin (Brockmann et al. 1952). The 
highest levels of fagopyrins were determined in f low-
ers and leaves (Stojilkovski et al. 2013). Kreft et al. 
(2013) evidenced that levels of fagopyrins increase 
gradually in sprout growth, especially in the light. 
Many researchers (Tavčar Benković et al. 2014, 
Tavčar Benković & Kreft 2015) reported that 
buckwheat sprouts contain fagopyrins that can cause 
photosensitization manifested as a skin irritation 
after exposure to sunlight. Phototoxic effects caused 
by fagopyrins are known as fagopyrism (Wender et 
al. 1943). Theurer et al. (1997) reported that fagopy-
rin was less phototoxic than hypericin. Aim of our 
research was to find out if the simultaneous addition 
of Se and I affected the amount of fagopyrins and 
rutin in the common buckwheat seeds.
1 INTRODUCTION
2 MATERIAL AND METHODS
Common buckwheat was sown on raised bed in the 
middle of July. At the beginning of flowering (28 days 
after sowing) plants were foliarly treated with solu-
tions of sodium selenite (10 mg Se(IV)/L), sodium se-
lenate (10 mg Se(VI)/L), potassium iodide (1000 mg 
I(–I)/L), potassium iodate (1000 mg I(V)/L), and com-
binations: 10 mg Se(IV)/L+1000 mg I(–I)/L; 10 mg 
Se(IV) /L+1000 mg I(V)/L, 10 mg Se(VI) /L+1000 mg 
I(–I)/L and 10 mg Se(VI)/L+1000 mg I(V)/L. After the 
ripening, we collected grains from the plants and 
measured the amount of fagopyrins and rutin. 
Sample of seeds was homogenized using a mill 
(Kika® Werke M20, Germany). Fagopyrins were ex-
tracted with acetone/water (HPLC grade, Sigma–Al-
drich). Dry samples (1 g) were suspended in 10 mL ac-
etone/water (9/1) and thoroughly mixed for 1 min. The 
suspensions were then incubated for 20 h at 37 °C. Sam-
ples were mixed for 1 min and centrifuged at 1000 rpm 
for 5 min at 25 °C. Aliquots of the clear supernatants 
were dispensed into 2 mL plastic test tubes (TPP, Trans-
dingen, Switzerland), and filtered through membrane 
filters (Millex-GN filters; pore size = 0.2 µm, Millipore). 
The 1 mL of filtrate extracts was pipetted into glass vial 
and exposed 1 h to daylight and then were transferred 
and analyzed by HPLC.. The HPLC system (Shimadzu 
Prominence) consisted of a system controller (CBM-
20A), a column oven (CPO-20AC) and a solvent deliv-
ery pump with a degasser (DGU-20A5) connected to a 
refrigerated autosampler (SIL-20AC) with a photodiode 
array (PDA) detector (SPD-M20A) that monitored the 
wavelengths 190–800 nm and a fluorescence detector 
(LC-20AD XR, excitation wavelength = 330 nm and 
emission wavelength = 590 nm). The responses of the 
detectors were recorded using LC Solution software 
version 1.24 SP1. The chromatography was performed 
at 40 °C and a flow rate of 2 mL/min using a Phe-
nomenex Kinetex® XB-C18 column (10 cm × 4.6 mm 
I.D., 2.7 µm particle size). The following gradient meth-
od using water (solvent A) and acetonitrile (solvent B), 
both containing 0.1 % trifluoroacetic acid, was utilized: 
0.01–0.5 min 0 % B, 0.5–6.0 min 0–51 % B, 6.0–6.01 
min 51 % B, 6.01–30 min 51–54 % B. The identity of 
GERM, LUTHAR, TAVČAR BENKOVIĆ, ZHOU, GOLOB & KACJAN MARŠIĆ: FAGOPYRIN AND RUTIN CONCENTRATION
47FOLIA BIOLOGICA ET GEOLOGICA 58/2 – 2017
fagopyrins was known from previous research (Tav-
čar Benković et al. 2014). The total content of fagopy-
rin was determined relative to the hypericin content, 
because its spectral characteristics and structure are 
similar to fagopyrin and fagopyrin as a standard refer-
ence compound was not available (Hinneburg et al. 
2005; Ozbolt et al. 2008; Stojilkovski et al.2013). All 
fagopyrin peaks were integrated together (Fig. 1).
Rutin was measured according to the method de-
scribed by Markham (1989). Briefly: powdered plant 
material (1 g) was homogenized with extracting sol-
vent (140:50:10 MeOH-H2O-CH3COOH, 20 mL) and 
filtered into volumetric flasks. Volumes were adjusted 
to 100 mL by addition of additional extracting solvent. 
To prepare the solutions for analysis, aliquots (2.5 mL) 
were transferred into 50 mL volumetric flasks and 
their volumes were made up with water. To each 10 mL 
of analysis solution, water (2 mL) and AlCl3 reagent 
(133 mg crystalline aluminium chloride and 400 mg 
crystalline sodium acetate dissolved in 100 mL of ex-
tracting solvent, 5 mL) were added and absorbances 
were recorded at 430 nm against a blank sample (10 mL 
of analysed solution plus 5 mL of water). The amount 
of flavonoids was calculated as a rutin equivalent from 
the calibration curve of rutin standard solutions, and 
expressed as g rutin/kg plant material.
Statistical analysis
The normal distribution of the data was tested using 
Shapiro-Wilk tests and homogeneity of variances was 
assessed using Levene’s test. For the statistical analysis 
of the data the factorial analysis of variance (ANOVA) 
was used. Dependent variable was compared by two 
independent variables: selenium (Se) treatment (two 
groups - Se(IV) and Se(VI), iodine (I) treatment (two 
groups - I(–I) and I(V)), and their combination Se × I. 
The level of significance was accepted at p < 0.05.
A statistical analysis of the content of fagopyrin 
relative to different treatments with Se and I was car-
ried out with one-way ANOVA by the Statgraphics XV 
program.
3 RESULTS AND DISCUSSION
The amount of fagopyrin ranged from 18.7 µg/gDM in 
Se(VI) treated plants to 33.9 µg/gDM in I(-I)+Se(VI) 
treated plants (Fig. 1). In the study of Kočevar Gla-
vač et al. 2017, where they measured the amount of 
fagopyrin in different parts of Tartary buckwheat, they 
determined 53.70 µg/gDM that was 1.8 fold higher 
than our results in common buckwheat. According to 
our knowledge, there are no reports about the effect of 
Se or I on the amount of fagopyrin in the plants in 
scientific literature. The amount of fagopyrins in the 
seeds of common buckwheat, foliarly treated with Se 
Figure 1: The effect of Se and I on the amount of fagopyrin in 
the seeds of common buckwheat. Data are given as mean 
value ± standard error (n = 4 for each treatment).
Slika 1: Vpliv Se in I na koncentraciojo fagopirina v zrnju 
navadne ajde. Podatki so srednje vrednosti ± standardna 
napaka (n = 4 za vsako tretiranje).
and I, was not significantly different in control in com-
parison to treated groups (Fig. 1).
In conclusion, it was evidenced that in the studied 
material Se or I did not have any effect on the amount 
of fagopyrins in seeds in foliarly treated common 
buckwheat. However,in future investigations, the at-
tention should be given on concentration of fagopyrins 
in the seeds of common buckwheat plants, treated with 
Se(VI). The fagopyrin concentration in Se(VI) plants is 
much lower in comparison to the control, but in pres-
ent experiment, in the case of high variation of the re-
sults, it cannot be concluded to be significant. 
In the grain from plants, treated with iodate, the 
addition of selenate and selenite had lowering impact 
to the amount of rutin (Table 1). In the grain of control 
plants and grain from plants, treated with iodide, nei-
ther treatment with the Se had an effect on the amount 
of rutin in the grains. If the plants were not sprayed 
with the solution of Se, iodate enhanced the amount of 
rutin in the grain, comparing to control. If the plants 
were treated with the solution of selenate, neither form 
of iodine affected the amount of rutin in the grain. 
Grains from plants, treated with iodide in combina-
tion with selenite, had higher amount of rutin compar-
ing to grain from control plants and plants, treated 
with selenite in combination with iodate and with se-
lenate in combination with iodate.
GERM, LUTHAR, TAVČAR BENKOVIĆ, ZHOU, GOLOB & KACJAN MARŠIĆ: FAGOPYRIN AND RUTIN CONCENTRATION
48 FOLIA BIOLOGICA ET GEOLOGICA 58/2 – 2017
Table 1: Concentration of rutin in grain harvested from 
plants treated with selenium and iodine
Preglednica 1: Koncentracija rutina v zrnju z rastlin treti-
ranih s selenom in jodom
Rutin  (mg g-1 )
Selenium 
0 2.42 ± 0.32b
Se(IV) 5.80 ± 0.32a
Se(VI) 1.91 ± 0.32b
Iodine
0 1.96 ± 0.32b
I(–I) 5.78 ± 0.78a
I(V) 2.39 ± 0.31b
Se× I
0+0 1.70 ± 0.17c
Se(IV)+0 2.16 ± 0.36bc
Se(VI)+0 2.02 ± 0.31bc
0+I(–I) 2.3 ± 0.2bc
0+I(V) 3.20 ± 0.3a
Se(IV) + I(–I) 2.6 ± 0.4ab
Se(IV) + I(V) 1.5 ± 0.3c
Se(VI) + I(–I) 2.2 ± 0.2bc
Se(VI) + I(V) 1.5 ± 0.2c
ANOVA
Selenium (Se) ***
Iodine (I) ***
Se × I ***
a Data are given as mean value ± standard error (n = 4 
for each treatment). Superscripted letters indicate sig-
nificant differences between the different treatments 
(p < 0.05).
a Navedeni podatki so povprečja± standardna napaka 
(n=4 za vsako tretiranje). Različne nadpisane črke 
označujejo značilnost razlik med tretiranji (p < 0.05).
Buckwheat contains high level of rutin in nearly 
all organs, including grain, cotyledons, leaves, stems, 
and flowers. Rutin concentrations, which were detect-
ed in our experiment, are somewhat higher in com-
parison to the results reported by Lee et al. (2016) and 
Danila et al. (2007), where rutin and other flavonoids 
measured in buckwheat grain and flour were analysed 
by HPLC. Amount of rutin was the highest in the 
grain, grown on foliarly treated plants with I(V). When 
Se was added in any form to iodate, the amount of 
rutin in the grain was reduced. Majority of other treat-
ments did not differ from the control. Fortification of 
plants with selenite did not affect the amount of rutin 
content in buckwheat grain compared to control. Sim-
ilarly, in the study of Dong et al. (2012) they found out, 
that concentration of rutin, an antioxidant with many 
interesting pharmacological effects (Kreft et al. 2002), 
was not significantly affected by selenium in the form 
of sodium selenite in Lycium chinense. On the con-
trary, in the study of Tian & Wang (2008) they found 
out that Se application less than 1.0 mg per kg soil in 
the form of sodium selenite increases the accumula-
tion and concentration of rutin in all organs of Tartary 
buckwheat.
POVZETEK
V času začetka cvetenja (28 dni po setvi na odprtem 
prostoru) so bile rastline tretirane z raztopinami Na 
selenita (10 mg Se(IV)/L), Na selenata (10 mg Se(VI)/L), 
K iodida (1000 mg I(–I)/L), K iodata (1000 mg I(V)/L) 
in s kombinacijami: 10 mg Se(IV)/L+1000 mg I(–I)/L; 
10 mg Se(IV) /L+1000 mg I(V)/L, 10 mg Se(VI) /L+1000 
mg I(–I)/L in 10 mg Se(VI)/L+1000 mg I(V)/L. Zrela 
semena so bila pobrana in zmleta. Izmerjene so bile 
koncentracije fagopirinov in rutina.
Koncentracija fagopirinov je bila od 18,7 µg/gDM 
v rastlinah, tretiranih s Se(VI), do 33,9 µg/gDM v ra-
stlinah, tretiranih z I-1+Se(VI) (slika 1). Kolikor nam je 
znano, doslej ni literaturnih podatkov o morebitnem 
vplivu selena ali joda na vsebnost fagopirinov v rastli-
nah. Pri tem poskusu se niso pokazale značilne razlike 
v koncentraciji fagopirinov med različno tretiranimi 
rastlinami, niti v primerjavi z netretirano kontrolo 
(slika 1)
Pri zrnju z rastlin, tretiranih z iodatom, selenatom 
in selenitom, je bilo ugotovljeno znižanje vsebnosti ru-
tina (razpredelnica 1). Pri zrnju z rastlin, tretiranih z 
jodidom, nobeno od tretiranj z raztopinami selena ni 
pokazalo značilnih razlik v primerjavi z netretirano 
kontrolo. V primeru rastlin, ki niso bile tretirane z raz-
topina selena se je pokazal vpliv jodata na povečano 
vsebnost rutina v primerjavi s kontrolo. Pri rastlinah, 
tretiranih z raztopino selenata, nobena od oblik joda ni 
vplivala na koncentracijo rutina v zrnju. Zrnje z rastlin, 
GERM, LUTHAR, TAVČAR BENKOVIĆ, ZHOU, GOLOB & KACJAN MARŠIĆ: FAGOPYRIN AND RUTIN CONCENTRATION
49FOLIA BIOLOGICA ET GEOLOGICA 58/2 – 2017
tretiranih z raztopinama joda v kombinaciji s selenom, 
je imelo višjo koncentracijo rutina v primerjavi s kon-
trolo in z rastlinami, ki so bile tretirane s selenitom in 
jodatom ali s selenatom v kombinaciji z jodatom. 
ACKNOWLEDGEMENT
The authors acknowledge the financial support from 
the Slovenian Research Agency (research core funding 
No. P1-0212 “Biology of Plants”, and No. P3-0395 “Nu-
trition and Public Health”). The authors acknowledge 
the projects (Optimisation of barley and buckwheat 
processing for sustainable use in high quality func-
tional food, ID L4-7552, The effect of iodine and sele-
nium on growth and quality of crops, ID J4-5524, and 
Chinese-Slovenian bilateral research project “The 
mechanism of mineral elements affecting the biosyn-
thesis of buckwheat secondary metabolites, and quali-
ty” ARRS-MS-BI-CN-JR-Prijava/2016/34, item 10, 
2016) were finacially supported by the Slovenian Re-
search Agency. Research was supported by EUFO-
RINNO 7th FP EU Infrastructure Programme (RegPot 
No. 315982). Authors are grateful to Prof. Dr. Vekosla-
va Stibilj for providing the Se and I solutions.
REFERENCES – LITERATURA
Bonafaccia, G., M. Marocchini & I. Kreft, 2003: Composition and technological properties of the flour and bran 
from common and tartary buckwheat. Food Chemisty (Amsterdam) 80(1): 9–15.  
https://doi.org/10.1016/S0308-8146(02)00228-5
Brockmann, H., E. Weber & G. Pampus, 1952: Protofagopyrin und Fagopyrin, die photodynamisch wirksamen 
Farbstoffe des Buchweizens (Fagopyrum esculentum). Justus Liebig’s Annalen der Chemie (Weinheim) 575(1): 
53-83.  
https://doi.org/10.1002/jlac.19525750106
Brozmanová, J., D. Mániková, V. Vlčková & M. Chovanec, 2010: Selenium: a double-edged sword for defense 
and offence in cancer. Archives of Toxicology (Berlin) 84(12): 919–938. https://doi.org/10.1007/s00204-010-
0595-8 
Cuderman, P. & V. Stibilj, 2010: Stability of Se species in plant extracts rich in phenolic substances. Anal Bioanal 
Chem (Dunaj) 396(4):1433-1439. https://doi.org/10.1007/s00216-009-3324-5 
Danila, A. M., A. Kotani, H. Hakamata & F. Kusu, 2007: Determination of rutin, catechin, epicatechin, and 
epicatechingallate in buckwheat Fagopyrum esculentum Moench by micro-high-performance liquid chromato-
graphy with electrochemical detection. Journal of Agricultural and Food Chemistry (München) 55(4): 1139–
1143. https://doi.org/10.1021/jf062815i 
Dong, J. Z., Y. Wang, S. H. Wang, L. P. Yin, G. J. Xu, C. Zheng, C. Lei & M. Z. Zhang, 2012: Selenium increases 
chlorogenic acid, chlorophyll and carotenoids of Lycium chinense Leaves. Sci Food Agric (Hoboken) 93(2): 310–
315. https://doi.org/10.1002/jsfa.5758
Eguchi, K., T. Anase & H. Osuga, 2009. Development of a high-performance liquid chromatography method to 
determine the fagopyrin content of Tartary buckwheat (Fagopyrum tataricum Gaertn.) and common buckwheat 
(F. esculentum Moench). Plant Production Science 12: 475–480.
Germ, M., N. Kacjan Maršić, J. Turk, M. Pirc, A. Golob, A. Jerše, A. Kroflič, H. Šircelj & V. Stibilj, 2015: 
The effect of different compounds of selenium and iodine on selected biochemical and physiological characteristi-
cs in common buckwheat and pumpkin sprouts. Acta Biologica Slovenica (Ljubljana) 58 (1): 35-44.
Golob, A., M. Germ, I. Kreft, I. Zelnik, U. Kristan & V. Stibilj, 2016: Selenium uptake and Se compounds in 
Se-treated buckwheat. Acta Botanica Croatica (Zagreb) 75 (1): 17-24. https://doi.org/10.1515/botcro-2016-0016 
Hinneburg, I., S. Kempe, H.H. Rüttinger & R.H.H Neubert 2005. A CE method for measuring phototoxicity in 
vitro. Chromatographia 62: 325–329.
Holasová, M., V. Fidlerová, H. Smrcinová, M. Orsak, J. Lachman & S. Vavreinová, 2002: Buckwheat - the 
source of antioxidant activity in functional foods. Food Research International (Hoboken) 35(2-3): 207–211. 
https://doi.org/10.1016/S0963-9969(01)00185-5 
GERM, LUTHAR, TAVČAR BENKOVIĆ, ZHOU, GOLOB & KACJAN MARŠIĆ: FAGOPYRIN AND RUTIN CONCENTRATION
50 FOLIA BIOLOGICA ET GEOLOGICA 58/2 – 2017
Jerše, A., N. Kacjan-Maršić, H. Šircelj, M. Germ, A. Kroflič & V. Stibilj, 2017: Seed soaking in I and Se solu-
tions increases concentrations of both elements and changes morphological and some physiological parameters of 
pea sprouts. Plant Physiol. Biochem. (Amsterdam) 118: 285-294. https://doi.org/10.1016/j.plaphy.2017.06.009 
Kočevar Glavač, N., K. Stojilkovski, S. Kreft, C. H. Park & I. Kreft, 2017: Determination of fagopyrins, rutin, 
and quercetin in Tartary buckwheat products. LWT - Food Science and Technology (Amsterdam) 79: 423-427. 
https://doi.org/10.1016/j.lwt.2017.01.068 
Kreft, I., 1995. Ajda. Ljubljana.
Kreft, S., B. Štrukelj, A. Gaberščik & I. Kreft, 2002: Rutin in buckwheat herbs grown at different UV-B radia-
tion levels: comparison of two UV spectrophotometric and an HPLC method. Journal of Experimental Botany 
(Oxford) 53(375): 1801–1804. https://doi.org/10.1093/jxb/erf032  
Kreft, S., D. Janeš & I. Kreft, 2013: The content of fagopyrin and polyphenols in common and Tartary buckwheat 
sprouts. Acta Pharmaceutica (Zagreb) 63(4): 553-560. https://doi.org/10.2478/acph-2013-0031
Kreft, M., 2016: Buckwheat phenolic metabolites in health and disease. Nutrition Research Reviews (Cambridge) 
29(1): 30-39. https://doi.org/10.1017/S0954422415000190
Lee, L. S., E. J. Choi, C. H. Kim, J. M. Sung, Y. B. Kim, D. H. Seo, H. W. Choi, Y. S. Choi, J. S. Kum & J. D. Park, 
2016: Contribution of flavonoids to the antioxidant properties of common and tartary buckwheat. Journal of 
Cereal Science (Amsterdam) 68: 181-186. https://doi.org/10.1016/j.jcs.2015.07.005 
Li, S. Q. & Q. H. Zhang, 2001: Advances in the development of functional foods from buckwheat. Critical Reviews 
in Food Science and Nutrition (Oxford) 41(6): 451–464. 
https://doi.org/10.1080/20014091091887
Markham K.R., 1989. Flavones, flavonols and their glycosides. In: Dey P.M., Harborne J.B. (eds.). Methods in 
Plant Biochemistry 1, pp. 197-235. Academic Press, London, UK. 
Osmić, A., A. Golob & M. Germ, 2017: The effect of selenium and iodine on selected biochemical and morphological 
characteristics in kohlrabi sprouts (Brassica oleracea L. var. gongylodes L.). Acta Biologica Slovenica (Ljubljana) 
60(1): 41–51.
Ožbolt, L., S. Kreft, I. Kreft, M. Germ & V. Stibilj, 2008. Distribution of selenium and phenolics in buckwheat plants 
grown from seeds soaked in Se solution and under different levels of UV-B radiation. Food Chemistry 110: 691–696.
Smoleń, S., I. Kowalska & W. Sady, 2014: Assessment of biofortification with iodine and selenium of lettuce culti-
vated in the NFT hydroponic system. Scientia Horticulturae (Amsterdam) 166: 9-16. https://doi.org/10.1016/j.
scienta.2013.11.011     
Smoleń, S., Ł. Skoczylas, R. Rakoczy, I. Ledwożyw-Smoleń, A. Kopeć, E. Piątkowska, R. Biezanowska-
-Kopeć, M. Pysz, A. Koronowicz, J. Kapusta-Duch & W. Sady, 2015: Mineral composition of field-grown 
lettuce (Lactuca sativa L.) depending on the diversified fertilization with iodine and selenium compounds. Acta 
Sci. Pol. Cultus (Olsztyn) 14(6): 97-114.
Smoleń, S., Ł. Skoczylas, I. Ledwożyw-Smoleń, R. Rakoczy, A. Kopeć, E. Piątkowska, R. Bieżanowska-
-Kopeć, A. Koronowicz & J. Kapusta-Duch, 2016: Biofortification of Carrot (Daucus carota L.) with Iodine 
and Selenium in a Field Experiment. Front. Plant Sci. (Bethesda) 7: 730. 
https://doi.org/10.3389/fpls.2016.00730    
Stojilkovski, K., N. Kočevar Glavač, S. Kreft & I. Kreft, 2013: Fagopyrin and flavonoid contents in common, 
Tartary, and cymosum buckwheat. Journal of Food Composition and Analysis (Amsterdam) 32(2): 126-130. 
https://doi.org/10.1016/j.jfca.2013.07.005
Suzuki, T., T. Morishita, S.-J. Kim, S.-U. Park, S.-H. Woo, T. Noda & S. Takigawa, 2015: Physiological Roles of 
Rutin in the Buckwheat Plant. Japan Agricultural Research Quarterly: JARQ (Ibaraki) 49 (1): 37-43. https://doi.
org/10.6090/jarq.49.37
Skrabanja, V., H. N. Laerke & I. Kreft, 1998: Effects of hydrothermal processing of buckwheat (Fagopyrum escu-
lentum Moench) groats on starch enzymatic availability in vitro and in vivo in rats. Journal of Cereal Science 
(Amsterdam) 28: 209–214.
Skrabanja, V., H. N. Laerke & I. Kreft, 2000: Protein-polyphenol interactions and in vivo digestibility of buckwheat 
groat proteins. Pflügers Archiv - European Journal of Applied Physiology (Berlin) 440 (Suppl. 1): R129–R131. 
https://doi.org/10.1007/s004240000033 
Skrabanja, V., H. G. M. Liljeberg Elmståhl, I. Kreft & I. M. E. Björck, 2001: Nutritional properties of starch 
in buckwheat products: Studies in Vitro and in Vivo. Journal of Agricultural and Food Chemistry (München) 
49(1): 490–496. https://doi.org/10.1021/jf000779w
GERM, LUTHAR, TAVČAR BENKOVIĆ, ZHOU, GOLOB & KACJAN MARŠIĆ: FAGOPYRIN AND RUTIN CONCENTRATION
51FOLIA BIOLOGICA ET GEOLOGICA 58/2 – 2017
Stojilkovski, K., N. Kočevar Glavač, S. Kreft, & I. Kreft, 2013: Fagopyrin and flavonoid contents in common, 
Tartary, and cymosum buckwheat. Journal of Food Composition and Analysis 32: 126-130.
Tavčar Benković, E., D. Žigon, M. Friedrich, J. Plavec & S. Kreft, 2014: Isolation, analysis and structures of 
phototoxic fagopyrins from buckwheat. Food Chem (Amsterdam) 143: 432−439. https://doi.org/10.1016/j.food-
chem.2013.07.118 
Tavčar Benković, E. & S. Kreft, 2015: Fagopyrins and Protofagopyrins: Detection, Analysis, and Potential Photo-
toxicity in Buckwheat. J. Agric. Food Chem. (Washington) 63(24): 5715–5724. https://doi.org/10.1021/acs.
jafc.5b01163  
Theurer, C., K. I. Gruetzner, S. J. Freeman & U. Koetter, 1997: In vitro phototoxicity of hypericin, fagopyrin 
rich, and fagopyrin free buckwheat herb extracts. Pharm. Pharmacol. Lett. (Stuttgart) 7(2/3): 113–115.
Tian, X. & Z. Wang, 2008: Effects of selenium application on content, distribution and accumulation of selenium, 
flavonoids and rutin in tartary buckwheat. Journal of Plant Nutrition and Fertilizer (Weinheim) 14(4): 721-727.
Wender, S. H., R. A. Gortner & O. L. Inman, 1943: The isolation of photosensitizing agents from buckwheat. 
Journal of the American Chemical Society (Washington) 65(9): 1733-1735. https://doi.org/10.1021/ja01249a023
White, P. J. & M. R. Broadley, 2009: Biofortification of crops with seven mineral elements often lacking in human 
diets – iron, zinc, copper, calcium, magnesium, selenium and iodine. New Phytologist (Bethesda) 182(1): 49–84. 
https://doi.org/10.1111/j.1469-8137.2008.02738.x
Zhu, Y.-G., Y. Huang, Y. Hu, Y. Liu & P. Christie, 2004: Interactions between selenium and iodine uptake by spi-
nach (Spinacia oleracea L.) in solution culture. Plant and Soil (Cham) 261(1-2): 99–105. http://doi.
org/10.1023/B:PLSO.0000035539.58054.e1 
Zimmermann, M. B. & J. Köhrle, 2002: The impact of iron and selenium deficiencies on iodine and thyroid meta-
bolism: biochemistry and relevance to public health. Thyroid (New Rochelle) 12(10): 867-878. https://doi.
org/10.1089/105072502761016494 
Figure 2: Chromatogram of fagopyrins obtained at HPLC analysis, peaks marked with A1, A2, X1, E, X2, X3, F and X4 show 
fagopyrins in seeds of common buckwheat
 Slika 2: Kromatogram fagopirina s HPLC analizo, vrhovi označeni z oznakami A1, A2, X1, E, X2, X3, F in X4 kažejo fag-
opirine v zrnih navadne ajde