## 4 Biological Activities of Ginger Polysaccharides
### Anti-Tussive Effects  
Cough is a common clinical symptom and a protective reflection of the body, which helps to clear the foreign material and secretions from the airway, thus facilitating the control of infection [64; 65]. However, frequent and severe coughing will still have a certain impact on the body, which may lead to syncope, urinary incontinence, pneumothorax, and even rib fracture. Clinically, codeine phosphate tablets are often used to treat frequent and severe dry cough with good effect, but long-term use has drug dependence and side effects. For this reason, safe and low-toxic compounds from natural sources have attracted researchers' attention, and polysaccharides are no exception. An experimental study in vivo showed that water-extracted polysaccharides (WEP) containing fraction from ginger rhizome has an anti-tussive effect, and the curative effect is basically the same as that of codeine phosphate. In this study, guinea pigs were stimulated with citric acid aerosol, and then treated with WEP, vehicle (water for injection), and positive control codeine phosphate, respectively. The cough number of guinea pigs were observed and recorded at 0, 30, 60, 120, and 300 min. The incidence of cough number was decreased from 6.2 \(\pm\) 0.43 (means \(\pm\) SEM) at 0 min (before extract administration) to 2.25 \(\pm\) 0.23 (means \(\pm\) SEM) at 30 min after WEP administration, while the cough number of perorally administered codeine phosphate (10 mg/kg body weight) decreased from 5.5 \(\pm\) 0.67 to 2.83 \(\pm\) 0.70 (mean \(\pm\) SEM) at the same time interval. WEP significantly inhibited the cough reflex of guinea pigs, and 25 mg/kg body weight WEP showed the maximum cough-suppressing activity at 30 min. In addition, the responsiveness of airway smooth muscle in vivo showed that WEP could reduce the number of coughs but did not affect the specific airway resistance of animals [48]. The above results provided a scientific basis for the traditional use of ginger.  
\begin{table}
\begin{tabular}{c c c c c} \hline \hline
**Biological** & **Compound Name** & **In Vitro or** & **Indicated Concentrations and** & **Ref.** \\
**Activities** & **In Vivo** & **Animal Experiments/Test System** & & \\ \hline \multirow{9}{*}{Anti-oxidant effects} & \multirow{9}{*}{Polysaccharides from finger stems and leaves (HWE-CGLP, UAF-GSLP, LAS-GSLP)} & \multirow{9}{*}{In vitro} & ABTS radical scavenging activity: These samples/ anti-oxidant capacities of ABTS, although better than those of HWF-CGLP and UAE-GSLP did not exceed those of Accorbic acid (VC\({}_{2}\))PPH radical scavenging activity. ASE-GSLP (C\({}_{60}\) = 0.95 mg/ml) \(<\) UAE-GSLP (C\({}_{60}\) = 0.95 mg/ml) \(<\) UAE-GSLP (C\({}_{60}\) = 2.87 mg/ml) \(<\) HWF-CGLP (C\({}_{61}\) = 3.58 mg/ml) \(<\) HWF-CGLP (C\({}_{62}\) = 3.58 mg/ml) \(<\) HWF-CGLP (C\({}_{63}\) = 0.95 mg/ml) \(<\) HWF-CGLP exhibited background radicals scavenging activity: ASE-GSLP exhibited higher hydroxyl radical scavenging activity than the other polysaccharides. Superoxide radical scavenging activity: The experimental K\({}_{50}\) values followed the trend ASE-GSLP \(<\) EAE-GSLP \(<\) EAE-GSLP \(<\) HWE-CGLP. & Cheathing activity of EAE-GSLP and UAE-GSLP might be partially due to the high contents of-COCOH and CO groups in their structures. Peric reducing power. In solutions of concentrations between 0.25 and 5.0 mg/ml, the reducing power of the EAE-GSLP was the greatest, followed by ASE-CSLP. & \\ \hline \multirow{9}{*}{Anti-tumor effects} & Five purified finger polysaccharides were obtained, namely HGP ECPI, EGTAP2, UCFI and UGP2 & \multirow{9}{*}{In vitro} & The human colon cancer HCT 116 cell line, human cervical cancer & UCFI has a strong inhibitory effect on these kinds of tumor cells such as HeLa and HCT116, oil which the inhibitory effect of UCFI on the human colon cancer HCT116 cell line, in relatively high (56.843 \(\pm\) 2.405%), which indicates that UCFI may be a potential drug for the treatment of colon cancer. & \\  & &