Further investigation of the roots of Rubia cordifolia resulted in the isolation of four new naphthohydroquinones and two naphthohydroquinone dimers, and one known naphthohydroquinone, one naphthoquinone, two anthraquinones and one naphthohydroquinone dimer. The structures of these compounds were established by various chemical and spectroscopic methods including two dimensional NMR techniques. Also, the isolated compounds were submitted to a bio-assay for cytotoxic and antitumor activity.

Trichinellosis is a serious disease with no satisfactory treatment. We aimed to assess the effect of myrrh (Commiphora molmol) and, for the first time, thyme (Thymus vulgaris L.) against enteral and encysted (parenteral) phases of Trichinella spiralis in mice compared with albendazole, and detect their effect on inducible nitric oxide synthase (iNOS) expression. Oral administration of 500 mg/kg of myrrh and thyme led to adult reduction (90.9%, 79.4%), while 1,000 mg/kg led to larvae reduction (79.6%, 71.3%), respectively. Administration of 50 mg/kg of albendazole resulted in adult and larvae reduction (94.2%, 90.9%). Positive immunostaining of inflammatory cells infiltrating intestinal mucosa and submucosa of all treated groups was detected. Myrrh-treated mice showed the highest iNOS expression followed by albendazole, then thyme. On the other hand, both myrrh and thyme-treated groups showed stronger iNOS expression of inflammatory cells infiltrating and surrounding encapsulated T. spiralis larvae than albendazole treated group. In conclusion, myrrh and thyme extracts are highly effective against both phases of T. spiralis and showed strong iNOS expressions, especially myrrh which could be a promising alternative drug. This experiment provides a basis for further exploration of this plant by isolation and retesting the active principles of both extracts against different stages of T. spiralis.

Chromatographic fractionation of the alcoholic extract of the dried fronds of Adiantum capillus-veneris L. (Adiantaceae) yielded seven compounds: four triterpenoidal compounds belonging to adiantane and filicane groups were isolated from the hexane fraction and identified as isoadiantone (1); isoadiantol-B (2); 3-methoxy-4-hydroxyfilicane (3) and 3,4-dihydroxyfilicane (4) and three flavonoids were isolated from the ethyl acetate fraction and identified as: quercetin (5), quercetin-3-O-glucoside (6) and quercetin-3-O-rutinoside (rutin) (7). The identification of the isolated compounds has been established through their physical, chemical and spectroscopic methods including IR, (1)H NMR, (13)C NMR, HSQC, HMBC, NOESY and MS. Biological studies of the total alcoholic extract, hexane fraction and some of the isolated compounds showed an anti-inflammatory activity while the hypoglycemic study of the total alcoholic extract showed a significant activity.

Seventeen daucane sesquiterpenoid esters, including a new one (4), were isolated from the root of Ferula hermonis Boiss. The structures of the isolated compounds were elucidated on the basis of spectroscopic evidence and correlated with known compounds. The relative stereochemistry of the new compound was determined using 2D NOESY and the most stable and the lowest energy conformation was determined using molecular modelling. The antimicrobial activity was evaluated by determination of MIC using the broth microdilution method against six bacterial strains and one fungal strain (Pseudomonas aeruginosa PAO1, Escherichia coli, Bacillus subtilis ATCC6633, Mycobacterium bovis BCG Pasteur, Mycobacterium tuberculosis H37Rv, Staphylococcus aureus ATCC6538 and Candida albicans SC5314). There was a significant indication that compounds 15, 16, 17 demonstrated potent activity against Gram +ve (S. aureus, B. subtilis), as well as Mycobacterium strains M. bovis BCG and M. tuberculosis H37Rv. None of the isolated compounds exhibited a significant antifungal activity. In the antioxidant study using the DPPH assay method, the highest radical scavenging activity was observed for compounds 15, 16, 17.

Giardiosis is one of the common parasitic diarrhoea in humans, especially in children, worldwide. Many drugs are used for its treatment, but there is evidence of drug resistance, insufficient efficacy and unpleasant side effects. Natural products are good candidates for discovering more effective anti-giardial compounds. This study evaluated the activity of extracts of Zingiber officinale (ginger) and Curcuma longa (curcumin) against Giardia lamblia in vitro and in vivo. Giardia cyst suspension was prepared from children faecal specimens. For the in vitro experiment, 1, 10 and 50 mg⁄mL dichloromethane extracts of ginger and curcumin separately were incubated with Giardia cysts for 5, 10, 30 and 60 min. The viability was distinguished by 0.1 % eosin and a haemocytometer. For the in vivo experiments, Balb/c mice were infected with Giardia cyst suspension containing 10,000 cysts/mL. Infected mice were administered 10 and 20 mg kg(-1) day(-1) ginger and curcumin extracts separately for 7 days post-infection. The effectiveness of the extracts was evaluated by faecal cyst and intestinal trophozoite counts and histopathological examination of the small intestine. In vitro ginger extract had a higher significant effect on cyst viability than curcumin, in a dose- and time-dependent manner. In vivo ginger (more effective) and curcumin extracts significantly treated infected mice, and this was evidenced by the faecal cyst and intestinal trophozoite counts reduction, in addition to evident improvement of intestinal mucosal damages induced by Giardia infection. Z. officinale and C. longa extracts may represent effective and natural therapeutic alternatives with low side effects and without drug resistance in the treatment of giardiosis.