Lycium ruthenicum Murr. is a traditional Chinese herb widely distributed in Tibet. The fruit, known as black goji, balck wolfberry is popular in traditional Chinese medicine. Black goji extracts contained abundant petunidin derivatives, with is and trans isomers of petunidin-3-p-coumaroyl-rutinoside-5-glucoside. The colorimetric and spectrophotometric traits of black goji anthocyanins were significantly impacted by solid-phase-extraction, pH, and acylation.
Petunidin-3-trans-p-coumaroyl-rutinoside-5-glucoside contributed most of the color expression of the black goji extract, and showed superior stability compared to other extracts over time. Acylation strengthened the petunidin derivatives color retention, and enhanced the color intensity and stability. Black goji anthocyanins produced various vivid hues over wide ranges of pH, making them promising candidates for natural colorants.
Compared with the red wolfberry (Lycium barbarum) and yellow wolfberry (Lycium chinense) , the black wolfberry (Lycium ruthenicum) contains rich protein. Red wolfberry had the highest carbohydrate content (76.12 g/100 g), while the content of Na in L. chinense was the highest (1 203.59 mg/100 g). L. ruthenicum was high in protein and low in carbohydrate, and the contents of ascorbic acid (29.06 mg/100 g), vitamin E (17.3 mg/100 g), carotene (5.23 μg/100 g), total amino acids (9.04 g/100 g), essential amino acids (3.82 g/100 g), non-essential amino acids (5.12 g/100 g) were also better than the other two kinds of wolfberry. In addition, Mg, Ca, Fe, Mn, Cu and Zn in L. ruthenicum were 2.89×102 mg/100 g, 5.31×102 mg/100 g, 36.1 mg/100 g, 2.30 mg/100 g, 8.10 mg/kg and 10.4 mg/kg, respectively.
Lycium ruthenicum Murr．grows wild on the plateau and desert without human intervention and pesticide pollution, it is a real pure natural green food. The Black Goji contains a variety of active components, has the functions of anti-oxidation, nourishing liver and improving eyesight, replenishing blood and calming the nerves, improving sleep, enhancing immunity, delaying aging and so on.
