Qualitative analysis of the functional groups was typically Free Essay Example

Qualitative analysis of the functional groups was typically identified by FTIR spectroscopy. As shown in Figures 2a-d, the CWSPS and HWSPS of the studied fruits exhibited a typical FTIR spectrum of polysaccharides (Fan, Lin, Luo, Chun, & Luo, 2014; Fan, He, Luo, Wang, & Luo, 2015; Luo et al., 2011; Luo, 2008; Razavi, Cui, Guo, & Ding, 2014), where the band in the range of 3421 to 3434.09cm-1 regions corresponds to the hydroxyl stretching vibration, meanwhile, the bands in the range of 2921 to 2923cm-1 corresponds to a weak C-H stretching vibration.

The presence of bound water is evidenced by the absorption bands in the range of 1600 to 1623cm-1, whereas the absorption bands at 1425-1448cm-1 refers to -CH3 and -CH2 bonding vibration. A characteristic band in the 1272-1000cm?1 region represents the stretching vibrations overlapped with ring vibrations of the (C-O-C) glycosidic band vibrations and the (C-OH) side groups. An absorption band at 701-777cm-1 corresponds to 1-?-D-galactose pyranose ring vibrations (Rakhmanberdyeva, Talipova, Gazizov, & Rakhimov, 2002).

Also, the bands at 875 cm?1 have been observed in ?-linked D-Galp (Galactopyranosyl) units in galactomannan distributed on the mannopyranosyl (Manp) main chain, respectively (Li, Wang, Jia, & Zhang, 2017). The absorptions bands in the range of 920-1137cm?1 are attributed to the bending vibrations of the C-O-C, C-O, glycosidic, and C-O-H bonds of the pyranose ring. With regards to the results of FTIR and monosaccharide analysis, the polysaccharides obtained from both G. triacanthos and D. regia fruits was found to belong mainly to the galactomannan type.

3.2. Bioactivity studies

3.2.1. Cytotoxic activity

Anticancer activity of CWSPS and HWSPS of both D.

regia and G. triacanthos fruits against different human cancer cell lines, was found to be a dose-dependent anti-proliferative effect on the cell viability. Table 4 summarizes the results of this effect. As is evident, very potent activity against breast carcinoma (MCF-7) with IC50 = 0.0634, 0.0282, 4.316 and 0.398 ?g/mL, cervix carcinoma (HELA) with IC50 = 0.6511, 4.12, 1.44 and 24.18 ?g/mL, Human Colon carcinoma (HCT116) with IC50 = 0.0166, 0.014, 14.778, and 0.3078 ?g/mL and liver carcinoma (HEPG2) with IC50= 2.296, 0.0183, 3.737 and 1.667?g/mL for CWSPS and HWSPS of D. regia and G. triacanthos fruits, respectively. Because plant extracts considered active as anti-cancer agents at IC50 ? 30 ?g/mL (Suffness, & Pezzuto, 1990), the polysaccharides isolated from both CWSPS and HWSPS of the plant fruits under investigation exhibited a considerable cytotoxicity against all tested cell lines and provide a scientific basis to develop anticancer drugs

3.2.2. Hepatoprotective activity

For exploring the hepatoprotective effect of CWSPS and HWSPS from both D. regia and G. triacanthos fruits, AST, ALT and ALP serum levels were used, one by one, as biochemical markers for acute liver damage (Liu, Zhu, Geng, Wang, & Ng, 2017). Comparing with the normal control group, treatment of mice with CCl4 alone showed acute liver damage which confirmed by marked elevation of the serum levels of AST, ALT and ALP (Zeng et al., 2016). Anyway, the elevated levels of these enzymes were markedly reduced by the pretreatment with CWSPS and HWSPS extracts, indicating that these polysaccharides dwindle liver damage and suppress the leakage of biochemical markers through cellular membranes at the dose of 100 mg/kg b.wt., as depicted in Tables 5-7. In case of AST (Table 5), the CWPS of G. triacanthos fruits extract exhibited the highest protective effect to the liver as detected from the increase in AST percentage at 72h from the level at zero time after liver damage (58.61%) followed by the HWPS of D. regia fruits (65.74%) as compared with silymarin (35.03%). On the other hand, the HWPS of D. regia fruits exhibited the highest curative activity to the damaged liver as detected from the percent of the decrease in the AST enzyme level at the last 7days relative to its level at 72 h. (25.68%) nearly equal to silymarin (27.44%) followed by the CWPS of G. triacanthos fruits (23.33%). In case of ALT (Table 6), the HWPS of G. triacanthos fruits followed by HWPS of D. regia fruits exhibited the highest protective activity to the liver as detected from the percent of the increase of ALT at 72 h after liver damage from the level at zero time (60.05 and 78.70%, respectively) as compared with silymarin (66.75%). In other words, the HWPS of D. regia fruits exhibited the greatest curative activity to the damaged liver as detected from the percent of the decrease in the ALT enzyme level at the last 7days from the level at 72 h. (27.63%) followed by the CWPS of G. triacanthos fruits (24.28%) compared with silymarin (37.52%). In case of ALP (Table 7), the HWPS of G. triacanthos fruits exhibited the highest protective activity to the liver as detected from the percent of the increase of ALP at 72 h after liver damage from the level at zero time (223.38%) as compared with silymarin (137.97%) active extract. Data of Table 7 show also that, the CWSPS of G. triacanthos fruits displayed the highest curative activity to the damaged liver as detected from the percent of the decrease in the ALP enzyme level at the last 7days from the level at 72 h. (38.96%) followed by the HWPS of D. regia fruits (35.96%) as compared with silymarin (56.91%).

3.2.3. Antioxidant activity

Table 8 shows that, HWSPS of both D. regia and G. triacanthos imparted best antioxidant activity (57.70 and 56.39%, respectively) as evidenced by the % of change of glutathione level of the diabetic control (59.47%). As a consequence, the polysaccharides isolated from both CWSPS and HWSPS of D. regia and G. triacanthos fruits could be considered as good sources of natural antioxidants, as supported by the previous reports of the antioxidant activity of the polysaccharide isolated from plant extracts (Han, Ye, & Wang, 2013; Kan, Chen, Wu, Wu, & Wu, 2015; Luo et al., 2011; Wang, Hu, Nie, Yu, & Xie, 2016; Xu, Chun-Ping, Xiao, & Mao, 2013).

4. Conclusion

Natural resources play a pivotal role in drug development. Medicinal plants, in particular, provide a rich source for bioactive phytoconstituents that are obviously free from undesirable side response and of powerful pharmacological actions. Taking these into account, cold water-soluble polysaccharide (CWSPS) and hot water-soluble polysaccharide (HWSPS) extracts of D. regia and G. triacanthos fruits were examined toward cytotoxic, hepatoprotective and antioxidant activities. The results obtained indicated that, the bioactivities of CWSPS and HWSPS from both D. regia and G. triacanthos fruits showed very potent in-vitro cytotoxic activity against human tumor cell lines: Breast carcinoma (MCF-7), human colon carcinoma (HCT-116), liver carcinoma (HEPG2) and cervix carcinoma (HELA). In addition, HWSPS of D. regia and CWSPS of G. triacanthos fruits possessed highest curative activity to the damaged liver as detected from the percent decrease in the AST, ALP and ALT enzymes level compared with silymarin as a positive reference drug. Also, HWSPS of both fruits exhibited a potent in-vivo antioxidant activity. These studies were carried out for the first time on the fruits of these species.