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The role of fallows in soil macrofauna conservation is examined, using cleared and undisturbed forest plots in Brazil as an illustration. Fallows were found to be closest to undisturbed forests in species richness, unlike lands converted to pastures, which demonstrated low species richness.

Cadmium (Cd) can enter soil through the use of fertilisers, calcareous, pesticides and industrial and/or domestic effluents. Cd can leach into groundwater and be taken up by plants, potentially leading to reductions in plant growth and yield. In soil, plant roots interact with heavy metal (HM)-tolerant microorganisms that may promote plant growth. Soil microorganisms may also be able to solubilise or mobilise soil metals, thereby acting as bioremediators. A better understanding of the interaction among plants, metals, microorganisms and soil will lead to improved plant tolerance. Two multi-tolerant bacteria from the Burkholderia genus were isolated from Cd-contaminated and Cd-uncontaminated soil of a coffee plantation. In addition to its high tolerance to Cd, the strain SCMS54 produces indole-acetic acid ( IAA), solubilises inorganic phosphate and produces siderophores, demonstrating its potential to contribute to beneficial plant-microorganism interactions. When interacting with tomato plants exposed to Cd, the bacterium led to decreases in plant peroxide and chlorosis levels, promoted relative plant growth and decreased the root absorption of Cd, resulting in increased plant tolerance to this highly toxic HM. The results indicated that the inoculation of tomato plants with Burkholderia sp. SCMS54 promotes better growth in plants cultivated in the presence of Cd. This phenomenon appears to be attributed to a mechanism that decreases Cd concentrations in the roots via a beneficial interaction between the bacteria and the plant roots. [ABSTRACT FROM AUTHOR]

Abstract: The benefits promoted by natural products on human health have motivated industry to search for alternative separation systems in order to purify active compounds present in renewable sources. Amongst natural products of current interest for food, pharmaceutical, cosmetic, and chemical industries is methyl chavicol (MC). MC is a natural ingredient found in several herbs as tarragon, sweet basil, sweet fennel, and their essential oils, and its widest application is in food industry as flavoring agent. In this work, basil essential oil was used as raw material to study MC concentration through a hybrid evaporation system. The evaporative system was constituted of a cylindrical evaporator, an internal condenser located concentrically to the evaporator, and an external condenser. It generates 3 outside streams: distilled, side, and residue, which were recovered at the bottom of external condenser, internal condenser, and evaporator, respectively. From experimental results, it was verified that higher MC concentration was reached at the side stream because its intermediate volatility when compared with other substances present in basil essential oil. Central composite experimental design using 2 factors and 4 replicates at central point was considered in this work to determine the effect of operating conditions on methyl chavicol separation. Response variables were methyl chavicol concentration (%MCside) at side stream, distilled (%D) and side (%S) streams amounts. The factors studied in this work were: evaporator temperature (Tevap) and feed flow rate (FFR). Analyzing the variables effects, two variables presented a statistically significant effect on distilled percentage: evaporator temperature and feed flow rate. For the side stream, the variables: evaporator temperature, feed flow rate, and the interaction between evaporator stream and feed flow rate influenced the side amount and methyl chavicol concentration. [Copyright &y& Elsevier]

Abstract: Distillates of the vegetable oil deodorization are composed of free fatty acids (FFA), sterols, tocopherols, sterol esters, hydrocarbons and breakdown products of fatty acids, aldehydes, ketones and acylglycerols. The content of free fatty acids in deodorizer distillates varies between 25 and 75%. Due to its high content, free fatty acid separation from deodorizer distillate is an important step to concentrate tocopherols to high purity. Tocopherols are valuable natural substances used in food, cosmetic and pharmaceutical industries. In this work, separation of free fatty acids from soybean oil deodorizer distillate (SODD) was investigated through molecular distillation, using different operating conditions. Evaporator temperature from 100 to 180°C and feed flow rate in the range of 1.5–23.0gmin−1 were used in the experiments. FFA and tocopherols contents were monitored in each stream generated by the molecular distillation process (distillate and residue streams). The intention is to determine the best operating conditions to produce a material with minimum FFA content and to minimize tocopherol losses during the process. Removal of FFA in the distillate stream resulted in a preliminary concentration of tocopherols, which is removed in the residue stream of the molecular distillation. The results showed that an efficient FFA separation from SODD with the lowest loss of tocopherols requires specific operating conditions. It was possible to obtain a material with 6.4% of FFA and 18.3% of tocopherols from a raw material composed by 57.8% of FFA and 8.97% of tocopherols, using 160°C of evaporator temperature and 10.4gmin−1 of feed flow rate. These results represent FFA elimination of 96.16% and tocopherol recovery of 81.23%. [Copyright &y& Elsevier]