The production of bleached Kraft pulp generates inorganic and organic residues that are usually deposited on the soil surface or land-filled. Studies conducted to address the impact of these wastes on the environment are scarce. In this work, Monterey pine (Pinus radiata D. Don), an important tree for pulping, was evaluated for germination and development under greenhouse conditions in forest soils exposed to solid residues of the cellulose industry using the Kraft process. Soils exposed to 10 to 60% ashes, 10 to 70% fly ashes, or 10 to 30% dregs allowed substantial seed germination and seedling growth. In contrast, soils exposed to low proportions of brown rejects, grits, or a mixture of all these residues were detrimental for germination, plant growth, or both. The strongest negative effect (no germination) was observed with as low as 10% grits. The changes in pH and/or water content caused by solid wastes did not correlate with detrimental effects observed in various soil-residue combinations. No significant changes in the microbial community of soils exposed to these solid residues were observed by determination of culturable counts, or by terminal-restriction fragment length polymorphism analysis of the microbial community DNA. The presence of organic residues did not affect the ability of the soil microbial community to remove typical pulp bleaching chloroaromatics. However, inorganic wastes strongly decreased the removal of such compounds.
The biomass production of Cymbopogon citratus shoots cultivated in bioreactors according to the temporary immersion (TIS) principle was assessed under different growth conditions. The effect of gassing with CO 2 -enriched air, reduced immersion frequency, vessel size and culture time on total phenolic and flavonoid content and free radical scavenging effect of the methanolic extracts was measured. From the TIS-culture of C. citratus, seven compounds were isolated and identified as caffeic acid (1), chlorogenic acid (2), neochlorogenic acid (3), p-hydroxybenzoic acid (4), p-hydroxybenzoic acid 3-O--d-glucoside (5), glutamic acid (6) and luteolin 6-C-fucopyranoside (7). The occurrence of compounds 1Ð7 and their variability in C. citratus grown under different TIS conditions was determined by HPLC. The free radical scavenging effect of the methanolic extract and compounds was measured by the discoloration of the free radical 1,1-diphenyl-2-picrylhydrazyl (DPPH). The main metabolites in 6-and 8-week-old cultures, both in 5 and 10 l vessels, were chlorogenic acid (2) (100Ð113 mg%) and neochlorogenic acid (3) (80Ð 119 mg%), while in the cultures with CO 2 -enriched air and reduced immersion frequency the main compound detected in the extracts was glutamic acid (6) (400 and 670 mg% for the green and white biomass and 619 and 630 mg% for the green and white biomass, respectively). The most active compounds, as free radical scavengers, in the DPPH discoloration assay were caffeic acid (1), chlorogenic acid (2), neochlorogenic acid (3) and the flavonoid luteolin 6-C-fucopyranoside (7).
A rapid in vitro propagation system leading to the formation of shoots, calli, roots, cell suspensions and plantlets was developed for the Andean medicinal plant Fabiana imbricata (Solanaceae). Massive propagation of shoots and roots was achieved by the temporary immersion system (TIS), morphogenesis and maintenance of cell suspensions by standard in vitro culture techniques. Oleanolic acid (OA), rutin, chlorogenic acid (CA) and scopoletin content in aerial parts of wild growing Fabiana imbricata plants as well as in plantlets regenerated in vitro, callus cultures, cell suspensions and biomass, obtained by the TIS system was assessed by HPLC. On a dry weight basis, the OA content in the aerial parts of the plant ranged between 2.26 and 3.47% while in vitro plantlets, callus and root cultures presented values ranging from not detected up to 0.14%. The rutin content of the samples presented a similar trend with maxima between 0.99 and 3.35% for the aerial parts of the plants to 0.02 to 0.20% for plantlets, 0.12% for cell suspensions and 0.28% for callus. Rutin was not detected in the roots grown by the TIS principle. The CA and scopoletin content in the aerial parts of F. imbricata ranged between 0.22Ð1.15 and < 0.01Ð0.55%, respectively. In the plantlets, the concentration of CA was 0.29 to 1.48% with scopoletin in the range 0.09 to 0.64% while in the callus sample, the CA and scopoletin content were 0.46 and 0.66%, respectively. A very different result was found in roots grown by TIS, where both OA and rutin were not detected and its main secondary metabolite, scopoletin was found between a range of 0.99 and 1.41% with CA between of 0.11 and 0.42%.
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