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Mg DW (mg + dw)
Selected AbstractsNutrients, diversity, and community structure of two phytotelm systems in a lower montane forest, Puerto RicoECOLOGICAL ENTOMOLOGY, Issue 3 2000Barbara A. Richardson Summary 1. Bromeliad and heliconia phytotelmata in the same forest area were compared in terms of their animal assemblages, nutrient inputs, and plant architecture. 2. For all major elements, nutrient inputs from canopy-derived debris and rainfall in bromeliads were significantly lower than those derived from decaying flower parts and plant secretions in heliconia bracts. Bromeliads contained significantly fewer organisms per unit volume of water and unit dry weight of organic matter than did heliconia inflorescences. They also contained a significantly lower animal biomass (199 mg DW from 15 bromeliads, 527 mg DW from 15 heliconia inflorescences). 3. Species richness was independent of abundance, demonstrating that, at least for small container habitats, higher abundance does not necessarily lead to a greater species richness. Communities were remarkably similar in patterns of relative abundance and species richness (23 spp. in bromeliads, 21 spp. in heliconia), probably due to functional similarities in plant architecture, with the two most abundant species comprising 60,62% of the total community. Coefficients of similarity were low because of marked differences in species assemblages. 4. Some taxa were phytotelm generalists but most showed a preference for one particular habitat, indicating differential selection in the choice of oviposition sites and larval development within the forest ecosystem. In common with many island communities, species richness was lower than that reported for these phytotelm habitats in mainland central and south America. [source] Improvement of ganoderic acid and Ganoderma polysaccharide biosynthesis by Ganoderma lucidum fermentation under the inducement of Cu2+BIOTECHNOLOGY PROGRESS, Issue 2 2010Ya-Jie Tang Abstract The cell growth and total accumulation of bioactive metabolites were significantly improved by Cu2+ addition during the submerged fermentation of medicinal mushroom Ganoderma lucidum. A mathematical model, constructed by response surface methodology combination with full factorial design, was applied to study the synergic effect of Cu2+ addition concentration and addition time. The optimal Cu2+ inducement strategy for the cell growth were different from those for the biosynthesis of ganoderic acid (GA) and Ganoderma polysaccharide. A multiple additions strategy of Cu2+ by adding each 1 mM Cu2+ on day 2, 6, 8 and 2 mM Cu2+ on day 4 was developed to enhance total accumulation of GA and extracellular polysaccharides. The highest GA content reached 3.0 ± 0.1 mg per 100 mg DW, which was increased by 76.5% and 33.9% compared with the control without Cu2+ addition and the peak value predicted by the constructed mathematical model, respectively. While, relatively higher addition concentration of Cu2+ (i.e., 5 mM) on the culture of day 4 led to higher content and total production of intracellular polysaccharides. © 2009 American Institute of Chemical Engineers Biotechnol. Prog., 2010 [source] A novel three-stage light irradiation strategy in the submerged fermentation of medicinal Mushroom Ganoderma lucidum for the efficient production of ganoderic acid and Ganoderma polysaccharidesBIOTECHNOLOGY PROGRESS, Issue 6 2008Wei Zhang Abstract A novel three-stage light irradiation strategy in the submerged fermentation of medicinal mushroom Ganoderma lucidum for the efficient production of bioactive metabolites ganoderic acid (GA) and Ganoderma polysaccharides was developed. Significance of light quality, i.e., blue light (390,500 nm, ,max = 470 nm), red light (560,700 nm, ,max = 625 nm), and white light (400,740 nm, ,max = 550 nm), was studied at first. Interestingly, there was a gradual decrease trend of GA content after the culture of day 2 when the maximal GA content was obtained, while GA content decreased slowly under white light irradiation after day 6. The dark environment was favorable to the specific GA biosynthesis (i.e., GA content) before day 6, and after that the optimum was white light irradiation. A relatively lower irradiation density of white light (i.e., 0.94 and 2.82 W/m2) was beneficial for the specific GA biosynthesis before day 6, while GA content was higher under higher irradiation density of white light (i.e., 4.70 and 9.40 W/m2) at the later-stage of cultivation. 4.70 W/m2 white light irradiation culture was the best from the viewpoint of GA accumulation. Therefore, a two-stage light irradiation strategy by combing the first 2 days dark culture with the following 4.70 W/m2 white light irradiation culture was developed. The highest GA production in the two-stage culture was 276.0 ± 12.5 mg/L, which was increased by 19% compared to 4.70 W/m2 white light irradiation culture (i.e., 232.4 ± 15.8 mg/L) and by 178% compared to the dark culture (i.e., 99.4 ± 1.0 mg/L). Although there still existed a gradual decrease trend of GA content after day 2 when the maximal GA content was obtained in the two-stage culture. Following three-stage light irradiation strategy was further demonstrated in order to turn around the sharp decrease of GA content after day 2. The first-stage was the 2-day dark culture; the second-stage was the following six-day 0.94 W/m2 white light irradiation culture, and the third-stage was 4.70 W/m2 white light irradiation culture until the end of fermentation. During the three-stage culture of G. lucidum, the gradual decrease trend of GA content after day 2 was turned around, which suggested that 0.94 W/m2 white light irradiation was beneficial for the metabolic flux towards the GA biosynthesis. The maximal GA content of 3.1 ± 0.1 mg/100 mg DW was obtained, which was higher by 41% compared to the two-stage culture. The maximal GA production (i.e., 466.3 ± 24.1 mg/L) and productivity (i.e., 38.9 mg/L per day) in the three-stage culture were 69 and 101% higher than those obtained in the two-stage culture. This is the first report investigating the significance of light irradiation on the medicinal mushroom submerged fermentation. Such work is very helpful to other mushroom fermentations for useful metabolite production. [source] A comparison among differently enriched rotifers (Brachionus plicatilis) and their effect on Atlantic cod (Gadus morhua) larvae early growth, survival and lipid compositionAQUACULTURE NUTRITION, Issue 1 2008A.S. GARCIA Abstract We evaluated the effect of differently enriched rotifers on the early growth, survival and lipid composition of Atlantic cod larvae (Gadus morhua). The enrichments tested were: (i) AlgaMac 2000®; (ii) AquaGrow® Advantage; and (iii) a combination of Pavlova sp. paste and AlgaMac 2000®. Larvae from treatment 3 [1.50 ± 0.11 mg dry weight (dw) and 7.10 ± 0.14 dw specific growth rate (SGR)] were heavier (P = 0.006) and grew faster (P = 0.004) than larvae from treatment 2 (1.03 ± 0.04 mg dw and 6.29 ± 0.04 dw SGR). No significant differences were found in the final weight and SGR among larvae from treatment 1 (1.21 ± 0.07 mg dw and 6.58 ± 0.20 dw SGR) and larvae from treatments 2 and 3. The treatment 3 also resulted in the best survival at the end of the experimental period, estimated to be 3 on a scale from 1 to 5, whereas the survival estimates for the two other groups were 1,2. Larvae from the treatment 3 reached 37 days posthatch with levels of ,6DPA 32-fold higher than newly hatched larvae. Differences in the larval enrichment of ,6DPA may explain the differences in growth and survival of the Atlantic cod larvae. [source] Experimental co-culture of low food-chain organisms, Sabella spallanzanii (Polychaeta, Sabellidae) and Cladophora prolifera (Chlorophyta, Cladophorales), in Porto Cesareo area (Mediterranean Sea)AQUACULTURE RESEARCH, Issue 10 2006Cataldo Pierri Abstract The filter feeder polychaete Sabella spallanzanii (Gmelin) was co-cultured with the green seaweed Cladophora prolifera (Roth.) Kunz, in an off-shore experimental system. Both species have previously been experimented as bioremediator organisms for waste treatment deriving from aquaculture farms and can have a high economic value as a byproduct of polyculture. The present experiment has been conducted in an area 2 miles off the coast of Porto Cesareo (Ionian sea, Southern Italy). The growth was followed in some modules anchored to the bottom at two different depths (15 and 25 m depth). The results indicate differences among replicates located at different depths. Both organisms show a faster growth at the shallower levels. Within this level, polychaetes reached a mean biomass of 860±74 mg dw (average±SE) per worm, 30 times larger than that of the starting point, after a standstill in the first period, probably due to the manipulation activities. The major growth has been recorded during the winter. Algae have shown an increase of 34 g ww month,1 (average±SE) in the shallower levels vs. only 11 g ww month,1 (average±SE) in the deeper levels. The RGR calculated after 60 days was 115% in the shallower levels vs. about 60% in the deeper ones. A considerable decrease in growth rate was observed during the last period; this was probably due to the presence of increasing fouling community on the rearing cages surely affecting the light intensity. 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