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This study investigated the influence of auxins on the growth of hairy roots and accumulation of anthocyanins, including cyanidin 3-O-glucoside (C3gl) and cyanidin 3-0-rutinoside (C3r), in the hairy root culture of tartary buckwheat cultivar Hokkai TIO. C3gl and C3r contents were evaluated using high- performance liquid chromatograph (HPLC). Four auxins, 2,4-dichlorophenoxyacetic acid (2,4-D), indoleacetic acid (IAA), indolebutyric acid (IBA) and naphthaleneacetic acid (NAA), were added to the medium of the hairy root cultures at diverse concentrations. IAA, IBA and 2,4-D promoted the growth of hairy roots since the dry weight of the roots was slightly higher than or comparable with that of the control. However, NAA at all concentrations suppressed the growth of hairy roots. Generally, auxin treatments resulted in higher accumulation of C3gl and C3r than that of the control except for 2.85 μM IAA and 2.69 μM NAA. The amount of C3gl and C3r after treatment with 4.92 μM IBA was the highest among all treatments and was 3.24 times more than that of the control. Our results suggested that auxins at appropriate concentrations might facilitate hairy root growth of tartary buckwheat and enhance the production of C3gl and C3r.

Radish sprouts and young seedlings are considered important dietary vegetables in Asian countries. In this study, we investigated the levels of glucosinolate and anthocyanin accumulation in radish seedlings in response to light and methyl jasmonate (MeJA) treatments. MeJA facilitated the accumulation of glucosinolate and anthocyanins under light conditions. The glucosinolate and anthocyanin contents in the radish seedlings that were exposed to light after MeJA treatment were higher than those of the seedlings that were grown in the dark without MeJA. At a concentration of 100 μM, MeJA led to the greatest accumulation of the most glucosinolates under both light and dark conditions. Under light conditions, the levels of glucoraphenin, glucoerucin, and glucotropaeolin accumulation were 1.53-, 1.60-, and 1.30-fold higher, respectively, than those of the control. Remarkable accumulations of glucobrassicin were observed under light conditions (4.4-, 6.7-, and 7.8-fold higher than that of the control following the application of 100, 300, and 500 μM MeJA, respectively). The level of cyanidin in the 300 μM MeJA-treated seedlings was double of that in the control without MeJA treatment. The highest level of pelargonidin was observed after treatment with 500 μM MeJA under light conditions; this level was 1.73 times higher than that in the control. A similar trend of anthocyaninaccumulation was observed in the radish seedlings following MeJA treatment under dark conditions, but the levels of anthocyanins were considerably lower in the seedlings that were grown in the dark. Our findings suggest that light and low concentrations of MeJA enhance the accumulations of glucosinolates and anthocyanins during the development of radish seedlings.

Gamma-aminobutyric acid (GABA), synthesized by glutamate decarboxylase (GAD), plays an important role in plants. To study the molecular mechanism of GAD regulation and to examine the levels of GABA in Scutellaria baicalensis, we isolated cDNA clones (SbGAD1 and 2) encoding GAD from S. baicalensis. The open reading frames of SbGAD1 and 2 were 1,503 and 1,494 bp long and had 450 and 497 amino acid residues, respectively. Quantitative real-time RT-PCR analysis was performed to show the variation of transcript levels among different organs of S. baicalensis. Transcript levels of SbGAD1 and 2 were highest in the root and flower, respectively. The GABA content of different parts (ranked in descending order) was as follows: leaf > flower > stem > root. We concluded that the expression pattern of SbGAD1 and 2 did not match the accumulation pattern of GABA in different organs. We presume that GABA biosynthesis might be more controlled by SbGAD2 than SbGAD1. These data will aid in future studies that seek to understand the mechanisms underlying GABA biosynthesis, an important amino acid that is synthesized by the GAD enzyme. To explain adequately the GABA biosynthesis mechanisms in S. baicalensis, the enzyme activities of SbGAD1 and 2 should be determined in the near future.

Here we present previously unreported glucosinolate production by hairy root cultures of broccoli (B. oleracea var. italica). Growth media greatly influenced the growth and glucosinolate content of hairy root cultures of broccoli. Seven glucosinolates, glucoraphanin, gluconapin, glucoerucin, glucobrassicin, 4- methoxyglucobrassicin, gluconasturtiin, and neoglucobrassicin, were identified by analysis of the broccoli hairy root cultures. Both half and full strength B5 and SH media enabled the highest accumulation of glucosinolates. In most cases, the levels of glucosinolates were higher in SH and BS media. Among the 7 glucosinolates, the accumulation of neoglucobrassicin was very high, irrespective of growth medium. The neoglucobrassicin content was 7.4-fold higher in SH medium than 1/2 MS, in which its level was the lowest. The 1/2 B5 medium supported the production of the highest amounts of glucobrassicin and 4- methoxyglucobrassicin, the levels for which were 36.2- and 7.9- fold higher, respectively, than their lowest content in 1/2 MS medium. The 1/2 SH medium enabled the highest accumulation of glucoraphanin and gluconapin in the broccoli hairy root cultures, whose levels were 1.8- and 4.6-fold higher, respectively, than their lowest content in 1/2 MS medium. Our results suggest that hairy root cultures of broccoli could be a valuable alternative approach for the production of glucosinolate compounds.

This study investigated the influence of auxins on the growth of hairy roots and accumulation of anthocyanins, including cyanidin 3- O-glucoside (C3gl) and cyanidin 3- O-rutinoside (C3r), in the hairy root culture of tartary buckwheat cultivar Hokkai T10. C3gl and C3r contents were evaluated using highperformance liquid chromatograph (HPLC). Four auxins, 2,4-dichlorophenoxyacetic acid (2,4-D), indoleacetic acid (IAA), indolebutyric acid (IBA) and naphthaleneacetic acid (NAA), were added to the medium of the hairy root cultures at diverse concentrations. IAA, IBA and 2,4-D promoted the growth of hairy roots since the dry weight of the roots was slightly higher than or comparable with that of the control. However, NAA at all concentrations suppressed the growth of hairy roots. Generally, auxin treatments resulted in higher accumulation of C3gl and C3r than that of the control except for 2.85 μM IAA and 2.69 μM NAA. The amount of C3gl and C3r after treatment with 4.92 μM IBA was the highest among all treatments and was 3.24 times more than that of the control. Our results suggested that auxins at appropriate concentrations might facilitate hairy root growth of tartary buckwheat and enhance the production of C3gl and C3r.

Radish sprouts and young seedlings are considered important dietary vegetables in Asian countries. In this study, we investigated the levels of glucosinolate and anthocyanin accumulation in radish seedlings in response to light and methyl jasmonate (MeJA) treatments. MeJA facilitated the accumulation of glucosinolate and anthocyanins under light conditions. The glucosinolate and anthocyanin contents in the radish seedlings that were exposed to light after MeJA treatment were higher than those of the seedlings that were grown in the dark without MeJA. At a concentration of 100 μM, MeJA led to the greatest accumulation of the most glucosinolates under both light and dark conditions. Under light conditions, the levels of glucoraphenin, glucoerucin, and glucotropaeolin accumulation were 1.53-, 1.60-, and 1.30-fold higher, respectively, than those of the control. Remarkable accumulations of glucobrassicin were observed under light conditions (4.4-, 6.7-, and 7.8-fold higher than that of the control following the application of 100, 300, and 500 μM MeJA, respectively). The level of cyanidin in the 300μM MeJA-treated seedlings was double of that in the control without MeJA treatment. The highest level of pelargonidin was observed after treatment with 500 μMMeJA under light conditions; this level was 1.73times higher than that in the control. A similar trend of anthocyaninaccumulation was observed in the radish seedlings following MeJA treatment under dark conditions, but the levels of anthocyanins were considerably lower in the seedlings that were grown in the dark. Our findings suggest that light and low concentrations of MeJA enhance the accumulations of glucosinolates and anthocyanins during the development of radish seedlings.

Chinese cabbage is one of the most important leafy vegetables widely used in East Asian cuisines. The glucosinolate (GSL) accumulation and transcript levels of 7 transcription factors (Dofl.l, IQD1-1, MYB28, MYB29, MYB34, MYB51, and MYB122, and their isoforms) involved in the biosynthesis of aliphatic and indolic glucosinolates (GSLs) were analyzed at different stages of Chinese cabbage (Brassica rapa ssp. pekinensis) seedlings under light and dark conditions using high performance liquid chromatography and quantitative real time PCR. During seedling development, transcription of almost all transcription factors under light conditions was higher expressed than under dark conditions. Five aliphatic GSLs (progoitrin, sinigrin, glucoalyssin, gluconapin, and glucobrassicanapin) and four indolic GSLs (4-hydroxyglucobrassicin, glucobrassicin, 4-methoxyglucobrassicin, and neoglucobrasscin) were detected. Total GSL contents under light conditions 6, 8, and 10 days after sowing (DAS) were 3.2-, 3.9-, and 6.9-fold higher, respectively than those of dark conditions. Interestingly, total GSL contents 2 {85.4 μmol/g dry weight (DW)} to 10 (7.74 μmol/g DW) DAS under dark conditions were gradually decreased. In this study, our results suggest that light affects the levels of GSL in Chinese cabbage seedlings. These results could be useful for obtaining cabbage varieties rich in GSLs.

The levels of resveratrol produced by hairy root cultures of Scutellaria baicalensis were investigated using different media of varying strengths and in the presence of various concentrations of auxins. The levels of resveratrol were higher when the hairy root cultures were maintained in full-strength Murashige and Skoog (MS) medium when compared with other growth media. The cultures grown in full-strength MS medium produced 2.5-fold higher resveratrol than those grown in half-strength B5 medium—the lowest resveratrol-producing medium. The levels of resveratrol varied significantly when cultures were grown in full-strength MS with varying concentrations of auxins. Supplementation of the media with the auxin indole acetic acid (IAA) at 0.1 mg/L produced the highest accumulation of resveratrol. Our findings reveal a valuable alternative approach for the production of resveratrol from S. baicalensis.