No abstract

Cistanche species, known as Rou Cong-Rong in Chinese, are an endangered wild species and are mainly distributed in the arid lands and warm deserts of northwestern China. Within Traditional Chinese Medicine (TCM), Herba Cistanche is applied as a tonic and/or in a formula for chronic renal disease, impotence, female infertility, morbid leucorrhea, profuse metrorrhagia, and senile constipation. The chemical constituents of Herba Cistanche mainly consist of volatile oils, non-volatile phenylethanoid glycosides (PhGs), iridoids, lignans, alditols, oligosaccharides, and polysaccharides. There have been an increasing number of studies focusing on its bio-activities, including antioxidation, neuroprotection, and antiaging. The objective of this review is to introduce this herb to the world. Its taxonomy, distribution, and corresponding biological functions and molecular mechanisms are addressed in this review.

In this study, quantitative structure activity relationship (QSAR) models for the antioxidant activity of polysaccharides were developed with 50% effective concentration (EC50) as the dependent variable. To establish optimum QSAR models, multiple linear regressions (MLR), support vector machines (SVM) and artificial neural networks (ANN) were used, and 11 molecular descriptors were selected. The optimum QSAR model for predicting EC50 of DPPH-scavenging activity consisted of four major descriptors. MLR model gave EC50 = 0.033Ara-0.041GalA-0.03GlcA-0.025PC+0.484, and MLR fitted the training set with R = 0.807. ANN model gave the improvement of training set (R = 0.96, RMSE = 0.018) and test set (R = 0.933, RMSE = 0.055) which indicated that it was more accurately than SVM and MLR models for predicting the DPPH-scavenging activity of polysaccharides. 67 compounds were used for predicting EC50 of the hydroxyl radicals scavenging activity of polysaccharides. MLR model gave EC50 = 0.12PC+0.083Fuc+0.013Rha-0.02UA+0.372. A comparison of results from models indicated that ANN model (R = 0.944, RMSE = 0.119) was also the best one for predicting the hydroxyl radicals scavenging activity of polysaccharides. MLR and ANN models showed that Ara and GalA appeared critical in determining EC50 of DPPH-scavenging activity, and Fuc, Rha, uronic acid and protein content had a great effect on the hydroxyl radicals scavenging activity of polysaccharides. The antioxidant activity of polysaccharide usually was high in MW range of 4000–100000, and the antioxidant activity could be affected simultaneously by other polysaccharide properties, such as uronic acid and Ara.

No abstract

Prior studies suggest a possibility that the anticancer property of garlic is more effective only when exposed directly to cancer cells than absorbed first by the normal epithelial cells of the gastrointestinal tract wall. We tested this possibility in two mouse models of highly aggressive malignancies that cannot yet be cured by conventional therapies: sarcoma 180- and EL4-induced lethal ascites. Daily oral gavages of raw garlic extract (RGE; equivalent to 100 mg wet weight) for 21 days failed to offer any meaningful effect in the mice with malignancies. However, the daily injection of the same amounts of the same materials for 21 days completely cured all the mice of cancer. This novel anticancer activity of RGE was present entirely in the size fraction of the molecules smaller than 3000 Dalton rather than the larger molecules and was completely partitioned into the organic phase rather than into the aqueous phase. One half of the anticancer activity was inactivated by heating at 100 °C for 10 min, suggesting that multiple components were concertedly involved. In a direct comparison, the RGE was significantly more effective in killing the cultured cancer cells in vitro than the extracts from other 21 raw vegetables and fruits. In cell culture, RGE killed a wide variety of different cancer cells regardless of species of origin and cell types. Cancer cells generally are well known to be defective in many common metabolic pathways present in their normal cell counterpart for processing normal nutrients. The metabolism of these otherwise normal nutrients could be stalled in the cancer cells and become cytotoxic. The most-effective way of treating cancer by RGE may be the direct injection instead of eating the cooked garlic.