Structural characterisation of algae Costaria costata fucoidan and its effects on CCl4-induced liver injury.

Fucoidan is a well-known natural product that is commonly found in brown algae and shows a variety of activities, including immunomodulation, antioxidation, and the combat of carcinogens. The fucoidan fractions of Costaria costata, a brown algae introduced from Japan and cultured in northern China, were studied. The fucoidan fractions were extracted, separated, and purified using a combinatorial procedure consisting of enzymolysis, ethanol precipitation, and DEAE and size-exclusion chromatographies. The fundamental characteristics of the four enriched fucoidan fractions (F1-F4), such as their sulphate content and monosaccharide composition, were investigated. FTIR and NMR spectroscopy were employed to further elucidate the structural features of the four fractions. It was found that the F1-F4 fractions all showed oxidative activity against hydroxyl radicals. The bioactive effects of the fucoidan fractions on CCl4-induced liver injury suggest their potential use as ingredients for functional foods or pharmaceuticals.

Novel antioxidative peptides from the protein hydrolysate of oysters (Crassostrea talienwhanensis).

The antioxidative activity of hydrolysate peptides from oysters (Crassostrea talienwhanensis) was investigated. After hydrolysis with subtilisin, the yields of the peptides that were soluble in trichloroacetic acid (TCA-soluble) and the antioxidant activities of the resulting hydrolysate were determined using an orthogonal design and a hydroxyl radical scavenging reaction. The hydrolysate was fractionated using Sephadex G-15 gel filtration chromatography, and the two resulting bioactive peptides were subsequently purified by RP-HPLC with a Kromasil C18 (ODS) column. The amino acid sequences were analyzed by nano-ESI-MS/MS. The critical reaction temperature, pH, hydrolysis time and enzyme-to-substrate (E/S) ratio were determined for the optimum hydrolysis with subtilisin, and the E/S ratio was found to be the most critical reaction condition. The amino acid sequences of the peptides (518 and 440 Da) were proline-valine-methionine-glycine-aspartic acid (PVMGA) and glutamine-histidine-glycine-valine (QHGV), respectively. These two novel peptides exhibited high antioxidative actions based on their hydroxyl and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activities.

A comparative study of intestinal helminths in pre-school-age urban and rural children in Morobe Province, Papua New Guinea.

Children aged between 1 month and 10 years from one rural coastal locality, two rural upland localities and two urban localities in Morobe Province, Papua New Guinea were examined between September 1980 and September 1982. Hookworm (predominantly Necator americanus), Ascaris lumbricoides and Trichuris trichiura increased in prevalence with age. The prevalence of Strongyloides fuelleborni subspecies kellyi, where present, was either highest in the < 1 year age group or similar in all age groups. N. americanus prevalence was between 59% and 83% in the 3 year age group except at the coastal locality, where it was 15%. A. lumbricoides prevalence in the 3 year age group was very low in one upland locality and between 7% and 41% for the other localities. T. trichiura prevalence in the 3 year age group was between 33% and 55% at the coastal and two urban localities, and very low at the two upland localities. S. f. kellyi prevalence in the < 1 year age group was 48% and 20% respectively at the two upland localities, 2% at one of the urban localities and not detected at the other localities. Strongyloides stercoralis was detected at both urban localities, but not at the coastal locality or at the upland locality where testing was done. Many children had infections of more than one species, and there was a significant association of A. lumbricoides with T. trichiura at the coastal and two urban localities. The presence of S. f. kellyi at one of the urban localities raises the possibility that this once isolated species may now be spreading as infected people visit and settle in the towns. Between 68% and 93% of children in the 3 year age group and between 65% and 100% in the 5 year age group were infected with at least one helminth species.

A comparative study of intestinal helminths in pre-school-age urban and rural children in Morobe Province, Papua New Guinea

Children aged between 1 month and 10 years from one rural coastal locality, two rural upland localities and two urban localities in Morobe Province, Papua New Guinea were examined between September 1980 and September 1982. Hookworm (predominantly Necator americanus), Ascaris lumbricoides and Trichuris trichiura increased in prevalence with age. The prevalence of Strongyloides fuelleborni subspecies kellyi, where present, was either highest in the < 1 year age group or similar in all age groups. N. americanus prevalence was between 59% and 83% in the 3 year age group except at the coastal locality, where it was 15%. A. lumbricoides prevalence in the 3 year age group was very low in one upland locality and between 7% and 41% for the other localities. T. trichiura prevalence in the 3 year age group was between 33% and 55% at the coastal and two urban localities, and very low at the two upland localities. S. f. kellyi prevalence in the < 1 year age group was 48% and 20% respectively at the two upland localities, 2% at one of the urban localities and not detected at the other localities. Strongyloides stercoralis was detected at both urban localities, but not at the coastal locality or at the upland locality where testing was done. Many children had infections of more than one species, and there was a significant association of A. lumbricoides with T. trichiura at the coastal and two urban localities. The presence of S. f. kellyi at one of the urban localities raises the possibility that this once isolated species may now be spreading as infected people visit and settle in the towns. Between 68% and 93% of children in the 3 year age group and between 65% and 100% in the 5 year age group were infected with at least one helminth species.