scholarly journals The Use of St. John’s Wort (Hypericum perforatum) Extract in Drinking Yoghurt Production and Determination of Changes Occuring During Storage

2021 ◽  
Author(s):  
Fadime SEYREKOĞLU ◽  
Hasan TEMİZ
Keyword(s):  
Hypericum Perforatum ◽  
St John’S Wort ◽  
St John's Wort

Determination of Hypericin in St. John's Wort (Hypericum perforatum L.) extracts using HPLC-ED

Planta Medica ◽  
2011 ◽  
Vol 77 (12) ◽  
Author(s):  
E Sofic ◽  
A Copra Janicijevic ◽  
M Maksimovic ◽  
I Tahirovic ◽  
L Klepo ◽  
...  
Keyword(s):  
Hypericum Perforatum ◽  
St John’S Wort ◽  
St John's Wort ◽  
Hypericum Perforatum L

scholarly journals Simultaneous Determination of the Predominant Hyperforins and Hypericins in St. John's Wort (Hypericum perforatum L.) by Liquid Chromatography

2000 ◽  
Vol 83 (4) ◽  
pp. 944-949 ◽  
Author(s):  
Dean E Gray ◽  
George E Rottinghaus ◽  
H E Gene Garrett ◽  
Stephen G Pallardy
Keyword(s):  
Liquid Chromatography ◽  
Simultaneous Determination ◽  
Hypericum Perforatum ◽  
Dry Weight ◽  
Active Constituents ◽  
St John’S Wort ◽  
St John's Wort ◽  
Relative Standard ◽  
Hypericum Perforatum L

Abstract Hypericin and hyperforin are believed to be among the active constituents in common St. John's wort (Hypericum perforatum L.). Presently, dietary supplements are generally standardized to contain specified levels of hypericin and hyperforin, and the related compounds, pseudohypericin and adhyperforin. A rapid method was developed for simultaneous determination of these 4 active constituents by liquid chromatography (LC). A 1 g portion of dried, finely ground leaf/flower sample is extracted with 20 mL methanol for 2 h. A 0.6 mL aliquot of the crude extract is combined with 5.4 mL acetonitrile–methanol (9 + 1) and passed through a mixed solid-phase cleanup column. The eluate is examined by LC for hyperforin, adhyperforin, hypericin, and pseudohypericin on a Hypersil reversed-phase column by using simultaneous ultraviolet (284 nm) and fluorescence detection (excitation, 470 nm; emission, 590 nm). The compounds are easily separated isocratically within 8 min with a mobile phase of acetonitrile–aqueous 0.1M triethylammonium acetate (8 + 2). Average recoveries of hyperforin and adhyperforin were 101.9 and 98.4%, respectively, for 3 sample mixtures containing concentrations ranging from approximately 0.2 to 1.5% combined hyperforins per gram dry weight. Average relative standard deviation (RSD) values for hyperforin and adhyperforin for all 3 mixtures were 18.9 and 18.0%, respectively. Average recoveries of hypericin and pseudohypericin were 88.6 and 93.3% respectively, from 3 sample mixtures containing concentrations ranging from approximately 0.2 to 0.4% combined hypericins per gram dry weight. Average RSD values for hypericin and pseudohypericin for all 3 mixtures were 3.8 and 4.2%, respectively.

Effect of herbicides on St John's wort (Hypericum perforatum L.)

1991 ◽  
Vol 31 (4) ◽  
pp. 499 ◽  
Author(s):  
MH Campbell ◽  
BR Milne ◽  
JJ Dellow ◽  
HI Nicol
Keyword(s):  
Hypericum Perforatum ◽  
New South ◽  
Arable Land ◽  
Ground Cover ◽  
Aerial Application ◽  
St John’S Wort ◽  
Strong Trend ◽  
St John's Wort ◽  
South Wales ◽  
Hypericum Perforatum L

The effect of type of herbicide and time and rate of application on the reduction in ground cover of St John's wort (Hypericum perforatum L.) was determined at Orange, New South Wales. In January, April, July and November 1988, 8 herbicide treatments including the currently used glyphosate and picloram + 2,4-D were applied to vigorously growing H. perforaturn, and the reduction in percentage ground cover was recorded in December 1989. Ineffective herbicides (a.i./ha) were tebuthiuron, 0.8-6.4 kg; metsulfuron, 5-20 g; and paraquat + diquat, 0.4 + 0.5 kg. The addition of metsulfuron (2.5 g a.i./ha) to glyphosate (0.9 and 1.8 kg a.i./ha) did not increase the effectiveness of the latter. Effective herbicides (kg a.i./ha) were triclopyr + picloram, 0.6 + 0.2; picloram + 2,4-D, 0.2 + 0.8; glyphosate, 1.8; and triclopyr, 1.92. There was a strong trend for these herbicides to be more effective in January and November than in April and July. Based on price, effectiveness and selectivity, triclopyr + picloram would be preferred to the other herbicides for boom and spot spraying, and glyphosate would be the only herbicide suitable for aerial application prior to sowing improved pastures on non-arable land.

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