Effect of Different Processing Methods on Phytochemical Contents and Neuroprotective Activity of Camellia euphlebia Leaves Extract

Camellia euphlebia is a new food source and traditional folk medicine in China. Previous studies have demonstrated the antidepressant activity of Camellia euphlebia extract by both in vivo and in vitro experiments. The effects of different pretreatments on phytochemical contents and neuroprotective activity of Camellia euphlebia extract were further investigated in order to develop an optimal processing method that makes the extraction more efficient. Six different powders of Camellia euphlebia leaves were prepared by different pretreatments. The particle size and morphology were examined by using a Malvern particle size analyzer and scanning electron microscopy, respectively. The results showed that the percentage of powder particle size within a range of 0.2∼40 μm was up to 79.18% after press-shear assisted interaction technology pretreatment by 2% addition of shellfish shell powder, and the cells were broken completely. Additionally, the contents of flavonoids, polysaccharides, polyphenols, saponins, and catechin in the extract were 11.78 ± 0.62%, 34.60 ± 3.37%, 6.15 ± 0.29%, 9.43 ± 1.19%, and 1.99 ± 0.11%, respectively, which were higher than those of the other five extracts. Moreover, the extract had the strongest neuroprotective activity by comparing the neuroprotective effect of different extracts on corticosterone-induced neurotoxicity in differentiated PC12 cells. It is concluded that press-shear assisted interaction technology with 2% addition of shellfish shell powder pretreatment, to a great extent, improved the dissolution of bioactive ingredients in Camellia euphlebia.

Evaluation of the Anxiolytic and Antidepressant Activities of the Aqueous Extract fromCamellia euphlebiaMerr. ex Sealy in Mice

Camellia euphlebiaMerr. ex Sealy is a traditional Chinese medicine that has been widely used for improvement of human emotions in the Guangxi Province of southern China. However, there are no studies about the anxiolytic and antidepressant activities ofCamellia euphlebia. This study evaluated the anxiolytic and antidepressant activities of the aqueous extract fromCamellia euphlebia(CEE) in mice. We found that administration of 400 mg/kg CEE or 20 mg/kg fluoxetine for 7 days significantly reduced the immobility time in both TST and FST. Oral administration of 100 mg/kg extract or 4 mg/kg diazepam for 7 days significantly increased the percentage of time spent and the number of entries into the open arms of the EPMT. In addition, the time spent by mice in the illuminated side of the LDBT was increased. Furthermore, pretreatment with 400 mg/kg CEE for 7 days significantly elevated the level of 5-HT and DA in the whole brain of mice. These results provide support for the potential anxiolytic and antidepressant activity ofCamellia euphlebiaand contribute towards validation of the traditional use ofCamellia euphlebiain the treatment of emotional disorders.