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Background: Tartary buckwheat (Fagopyrum tataricum), an excellent edible and medicinal crop, has been widely used as a daily diet and traditional medicine for a long time. The major functional components of Fagopyrum tataricum have been demonstrated to be flavonoids (i.e. rutin and quercetin), which had notable andioxidant, antidiabetic, hypocholesterolemic and antitumor activities. Hairy root culture is a convenient and efficient plant tissue culture system for large scale production of bioactive metabolites. Objective: To enhance the functional flavonoids production in hairy root culture of F. tataricum. Materials and Methods: The elicitation treatment in combination with medium renewal strategy was applied for efficient promoting flavonoids production in F. tataricum hairy root cultures. Results: The exogenous yeast polysaccharide (YPS) elicitor notably stimulated the functional metabolites production in F. tataricum hairy root cultures, and the stimulation effect was concentration-dependent. Combination with the YPS elicitation (200 mg/L) and medium renewal process, the maximal flavonoids yield was enhanced to 47.13 mg/L, about 3.2-fold in comparison with the control culture of 14.88 mg/L. Moreover, this research also revealed the accumulation of these bioactive metabolites resulted from the stimulation of the phenylpropanoid pathway by YPS treatment. These results indicated that the F. tataricum hairy root culture could be an effective system for rutin and quercetin production. [ABSTRACT FROM AUTHOR]

Background: Buckwheat (Fagopyrum spp., Polygonaceae) is a widely planted food crop. Flavonoids, including quercetin, rutin, and kaempferol, are the main bioactive components in tartary buckwheat (Fagopyrum tataricum (L.) Gaertn). From the nutriological and pharmacological perspectives, flavonoids have great value in controlling blood glucose and blood pressure levels, and they also have antioxidant properties. Objective: To optimize the conditions for extraction of quercetin, rutin, and kaempferol from F. tataricum. Materials and Methods: A combination of ultrasound-assisted extraction (UAE) and response surface methodology (RSM) was used for flavonoid extraction and yield assessment. The RSM was based on a three-level, three-variable Box-Behnken design. Results: Flavonoids were optimally extracted from F. tataricum by using 72% methanol, at 60°C, for 21 minutes. Under these conditions, the obtained extraction yield of the total flavonoids was 3.94%. Conclusion: The results indicated that the UAE method was effective for extraction of flavonoids from tartary buckwheat. [ABSTRACT FROM AUTHOR]

Purpose: To isolate and identify the fungal endophytes of Fagopyrum tataricum and assess their antimicrobial activity. Methods: The fungal isolates were identified according to their morphological characters and internal transcribed spacer (ITS) sequence analysis. Both broth-dilution-colorimetric assay and spore germination test were employed to assess the antimicrobial activity of fungal mycelia extracts. Results: A total of 72 endophytic fungal isolates were successfully obtained from the healthy tissues of F. tataricum. On the basis of their morphological and molecular characteristics, thirteen distinct fungal isolates were identified, and belonged to Alternaria, Bionectria, Botryosphaeria, Fusarium, Guignardia, Nectria, Neonectria, Phomopsis, Pseudocercospora and Verticillium spp. Of these, Pseudocercospora owned the maximum colonization frequency (15.3 %), next for Alternaria (12.5 %) and Neonectria (11.1 %). Through antimicrobial screening assays, six endophytes (Fataf-4, 6, 9, 11, 12 and 15) were active against Bacillus subtilis, Staphylococcus aureus, Agrobacterium tumefaciens, Escherichia coli and Pseudomonas lachrymans, and their minimal inhibitory concentration (MIC) ranged from 0.125 to 2.00 mg/mL. Furthermore, the endophytes, Fataf-9 and Fataf-11, also displayed strong inhibitory activity on the spore germination of F. oxysporum f. sp. vasinfectum and F. oxysporum f. sp. cucumerinum, and their median effective inhibitory concentration (IC50) was 0.356, 0.463, 0.451 and 0.489 mg/mL, respectively. Conclusion: The endophytic fungi of F. tataricum appear to be diverse and promising in their antimicrobial activity, and may represent a potential source of antibiotics for agriculture and/or pharmaceutical applications. [ABSTRACT FROM AUTHOR]