Cold and hot aqueous extraction method (CEM and HEM) of polysaccharides of Dictyopetris membraceae, Padina pavonia, Colpomenia sinusa, Enteromorpha intestinalis, Corallina officinalis, Petrocladia capillraceae and Jania rubes were performed and their physicochemical characterization were studied. The average molecular weight of polysaccharides was (2.15×10 to 6.08×10 gmol) and composed of sugars (39.40 69.92% w/w), protein (4.0-25.0%), sulfur (0.8711.59%), and ash (7.91-30.24%). The polysaccharides devoid antiviral effect on HCV, whereas, HEM of P. capillraceae inhibited adenovirus type 40 into 46.6%. Both polysaccharide extracts of J. rubens and HEM of C. sinuosa exhibited most potent cytotocicity on HepG2 with an IC50 10.73, 38.47 and 38.75 μg/ml, respectively. Polysaccharides from J. rubens, C. sinuosa, C. officinalis and P. pavonia showed various scavenging abilities against DPPH (9.10-58.97%) and nitric oxide (28.57-92.86%). While, polysaccharides of C. sinuosa, D. membranacea and E. intestinalis displayed in vitro hypolipidemic effect. Polysaccharides might become important source for drug development for treating hepatic disease.

Cancer is a public health problem worldwide. According to WHO, 20 million people in the world suffer from cancer, a figure projected to rise to 30 million within 20 years. Cancer causes 7.1 million deaths annually (12.6% of the global total) (WHO, 2004).

The microalga Spirulina platensis contains 11.09% w/w of total polysaccharides. The water soluble polysaccharides, obtained by cold and hot water extract method, yielded 4.45 and 3.37% w/w, respectively. The total sugar content of cold and hot polysaccharide extracts were 67.29 and 64.66%, respectively. Furthermore according to GC analysis twelve and eleven sugars could be identified in cold and hot extracts, respectively. Glucose, galactose and mannose are predominant sugars in both extracts. The cold and hot water extracts significantly reduced the replication of Hepatitis C Virus (genotype 4) as well as scavenging ability against nitric oxide in concentration-dependent manner. Moreover, the hot extract exhibited cytotoxic activity against HepG2 (human cell line) while the cold extract showed hypolipidemic activity.

The essential oil from fresh flowers of Khaya grandifoliola C.DC and. Khaya senegalensis A. Juss were obtained by hydro distillation method, in a modified Likens and Nickerson apparatus which allowed the distillation and simultaneous extraction of the volatile components in an organic solvent (n-pentane). The n-pentane layer was collected, filtered over anhydrous sodium sulfate, cautiously evaporated. A content of 0.09 – 0.1% essential oil was established. The chemical composition of the essential oil was analyzed by gas-chromatography coupled with mass spectrometry. Sesquiterpenes represents (88%) of the identified compounds. The main compounds identified in essential oil were: caryophyllene-oxide (23.01%), isocaryophyllene, (Z) (21.99%), α- Humulene (13.46%) in K. grandifoliola. while: caryophyllene-oxide (14.85%), trans-Caryophyllene (43.59%), α- Humulene (15.72%) in K. senegalensis. The oils were tested for cytotoxic activity against HepG-2, MCF-7 and HCT-116 cell lines. Cell viability was assessed by the mitochondrial dependent reduction of yellow MTT using Doxorubicin as reference drug. K. grandifoliola and K. senegalensis oil displayed cytotoxic activity with LC50 (21.6, 26.1, 37.6 ppm) and (61.1, 79.7, 61 ppm) respectively. Sesquiterpene content of the oils may contribute to their cytotoxic activity. This is the first study for oil from khaya species.

Five phenolics were isolated for the first time from the ethanol extract of Khaya grandifoliola leaves. These compounds were identified [1] using spectroscopic analysis (UV, 1H-NMR, 13C-NMR and ESI) as Quercetin 3-O-rhamnoglucoside (rutin), Quercetin 3-O-rhamnoside, Quercetin 3-O-glucoside, Quercetin aglycon and the new 6- methoxycoumarin, 7- arabinofuranoside. Desmutagenic and antimutagenic [2] activities of specimen extracts of immaculate khaya grandifoliola leaves and flowers were ascertained by measuring the inhibition of Salmonella typhimurium TA 100 His+ revertants induced by ethyl methane sulphonate EMS and ribose lysine RL. A frustration of the induced reversion was observed. The alcoholic extract of both leaves and flowers of khaya grandifoliola exhibited desmutagenic and antimutagenic activity against EMS and RL induced reversion.