Fucoxanthin Content of Five Species Brown Seaweed from Talango District, Madura Island

Fucoxanthin content of five brown seaweed species of East Java collected from Talango district （Madura sea-Jawa sea） namely Padina australis, Turbinaria conoides, Sargassum cinereum, Sargassum filipendula and Sargassum echinocarpum were determined and samples were collected using Global Positioning System （GPS）. Fucoxanthin from those samples was determined using Thin Layer Chromatography （TLC）, High Pressure Liquid Chromatography （HPLC） and Spectrophotometer UV-Vis and the results were then calculated using Seely equation. The pigments separation using HPLC gave a better result compared to TLC, and beside fucoxanthin otlher pigments namely chlorophyll and β carotene were also identified in these samples. Four points of sampling location were chosen using GPS and spot with coordinate positions observed were 113.94444° EL-7.08795° SA; 113.94231° EL-7.08913° SA. The results showed that fucoxanthin content were as follow： Padina australis 0.2674± 0.0046 mg/g; Turbinaria conoides 0.2134± 0.0100 mg/g; Sargassum filipendula 0.1957 ± 0.0173 mg/g; Sargassum cinereum 0.1640 ± 0.0092 mg/g and Sargassum echinocarpum 0.1576 ± 0.0001 mg/g. It can be concluded that Padina australis and Turbinaria conoides contain the most amount of fucoxanthin and it is possible to be cultivated as edible brown seaweed fucoxanthin resources.

Anti-allergic effects of ethanol extracts from brown seaweeds

Ethanol extracts of brown seaweeds from Pakistan and China were isolated and compared for their antiallergenic activities. They included Sargassum tennerimum (ST) and Sargassum cervicorne (SC) from Pakistan, and Sargassum gramini- folium turn (SG), Sargassum thunbergii (STH), and Laminaria japonica (LJ) from China. The ethanol extracts of these brown seaweeds were optimized at 85% (v/v) ethanol for the maximum yield of phlorotannin, an inhibitor against hyaluronidase. Total phlorotannins contained in the crude extracts were measured as 1.71% (SG), 0.74% (STH), 0.97% (LJ), 3.30% (SC), and 5.06% (ST). The 50% inhibitory concentrations (IC50) of Pakistani SC and ST were 109.5 and 21 μg/ml, respectively, lower than those of Chinese SG, STH, and LJ (134, 269, and 148 μg/ml, respectively). An antiallergic drug, disodium cromoglycate (DSCG), had an IC50=39 μg/ml, and a natural inhibitor of hyaluronidase, catechin, had an IC50=20 μg/ml. The IC50 of ST extract was found similar to that of catechin (21 vs 20 μg/ml) and lower than that of DSCG (21 vs 39 μg/ml). This suggests that ST is a potent inhibitor of hyaluronidase, indicating a promising future development of natural antiallergic medicines or functional foods.

Genetic variation of Laminaria japonica (Phaeophyta) populations in China as revealed by RAPD markers

For the population genetics analysis of the naturally grown brown seaweed Laminaria japonica （Laminariales,Phaeophyta） sampled from Dalian,Yantai,Weihai,Rongcheng and Qingdao in China,ten primers were employed to produce 88 bands as revealed by randomly amplified polymorphic DNA （RAPD） markers,and all these bands were polymorphic.According to these band patterns,there were 94 distinct phenotypes occurred in 100 samples indicating the high heterozygosity of this kelp.Dalian population samples showed the highest percentage of polymorphism （71.67%）,and also the higher diversity estimated on the basis of the Shannon’s index （8.498）,suggesting that this population could be chosen as the best resource for genetic breeding.The highest diversity of Yantai population possibly resulted from the introduction of L.longissima used for interspecific cross breeding with L.japonica cultivated in China.From Dalian southwards to Qingdao,the genetic variation of the five populations became less with a decrease in latitude,possibly due to the natural selection especially of high temperature.The genetic distance （Φ ST values） of the five populations was a little significantly correlated with the geographical distance （r=0.496） at P =0.05 by Mantel’s test.Weihai,Rongcheng and Yantai populations were closely grouped genetically together by Neighbor-joining cluster analysis probably in that the dispersal of the kelp by propagules more easily occurring in the range of relatively short distance.The analysis of molecular variance （AMOVA） also demonstrated that the relatively higher variation occurred among populations （71.49%） at an extremely significant level （P 0.000 1）.All these evidence showed that there was a relatively distinct genetic differentiation among the sampled kelp populations,and L.japonica grown in China was also rather heterozygous in heredity.

Sargassum polycystum extract attenuates oxidative stress on diabetic rats

Objective:To evaluate hypoglycemic,free radical scavenging and improving antioxidant enzymes activities on diabetic-induced streptozotocin rats by Sargassum polycystum(S.polycystum)extract.Methods:The seaweed extract was obtained by maceration,concentration and freeze drying,respectively.Acute toxicity was investigated on 25 rats.Forty eight of rats were used to study anti-stress oxidative of extract and divided into eight groups,where the first and fifth group were normal and diabetic control.The normal and diabetic treated groups were administered orally with extracts of S.polycystum for 28 days.The blood glucose and body weight of rats were observed each week.The blood was obtained for determination of malondialdehide,superoxide dismutase,catalase and glutathione peroxidase,respectively.Results:Extract of S.polycystum revealed no mortality and it was grouped as relatively nontoxic substance.The normal rats revealed difference statistically to the diabetic rats.The diabetic rats treated extract showed decreasing of blood glucose level and increasing of body weight.The diabetic rats were treated with 450 mg/kg of extract showed the higher oxidative stress augmentation than other diabetic treatments.It was caused free radical scavenging and induction of antioxidant enzymes activity by brown seaweed extract.Conclusions:The extract of S.echinocarpum reduce oxidative stress on diabetic-induced streptozotocin rats and demonstrate as candidate of antioxidant diabetic substances.