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Annually, amounts of orange waste are directed into the environment. The orange waste oil is a potential source of compounds of interest and alternatives have been explored to highlight their potential. Appropriately, this study investigated the effects of oil extraction processes involving pressurized liquids (PLE) and supercritical CO2 (SC-CO2) on orange residues. The results were compared with the standard Soxhlet procedure. The optimization of the operational parameters was established based on the adjustment of different process conditions for pressure (150 and 350 bar), extraction time (20 and 60 min), and temperature (40 and 60 °C). The results indicated that the maximum oil yields for orange peel and pomace were 37.76 % and 43.39 %, respectively, for the PLE approach. The SC-CO2 expressed maximum yields of up to 0.50 % and 0.38 % for peel and pomace, respectively. The GC-MS analysis reported the concentration of bioactive compounds after the distinct extraction methods. [ABSTRACT FROM AUTHOR]

The occurrence of insect pests in crops directly affects the yield of plants and grains. This scenario led to the mass investigation of chemical products that overcome these adversities and provide control potential. Nonetheless, over the years, this strategy resulted in high production costs, generation of waste harmful to the environment, and resistance of target insects. The adoption of alternative practices, such as the formulation and production of products of microbial origin, emerges as an encouraging tool compared to control alternatives, indicating a sustainability bias, and allowing a reduction in the risks of human and animal contamination. The purpose of this study was to perform bioprospecting for microbial agents with potential insecticidal effects. The isolated microorganisms were submitted to submerged fermentation, at 28 °C and 120 rpm, for seven days. The fermented broth was filtered using a vacuum pump and centrifuged at 3200× g and 10 °C for 10 min. Initially, 163 microbial agents were collected. Subsequently, a pre-selection of the 50 most promising bioagents was conducted, based on the mortality rates (%) of the applied isolates to target pests. Furthermore, a global mathematical modeling design was created, indicating the best potential microorganisms. Moreover, to stipulate the difference between treatments, dilutions of the fermented broths of each microorganism were conducted (n × 10−5–n × 10−8). Mortality was maximum (100%) for Helicoverpa zea and Euschistus heros. Other encouraging results were indicated in the control of Anticarsia gemmatalis and Chrysodeixis includens (up to 87.5%) and Elasmopalpus lignosellus (up to approximately 83.5%). Fungal isolates were identified as Talaromyces piceae. Among the bacteria, based on sequencing of the 16S ribosomal gene, the isolates were identified as Lysinibacillus fusiformis, Paenibacillus ottowii, and Clostridium sphenoides. The results obtained are relevant to the scientific community and, especially, are interesting for companies that are operating in this field in the agricultural sector. [ABSTRACT FROM AUTHOR]

Ultrasound-assisted extraction is an interesting tool for obtaining bioactive compounds from plant matrices applicable as agricultural bio-inputs, as it increases the extraction efficiency, reducing the process time and the use of solvents. This technique uses ultrasonic waves to break down plant cell walls, releasing bioactive compounds quickly and effectively and promoting a sustainable path to obtaining bio-inputs. Accordingly, this research study reports pioneering results regarding the herbicidal and fungicidal potential of different extracts obtained from Senecio brasiliensis (samples from flowers, leaves, and stalks) and Solanum viarum (samples from fruits and roots), two weeds typically found in rural areas of South America. The fungicidal activity of the samples was tested on two fungi, i.e., Fusarium graminearum and Sclerotinia sclerotiorum, while the herbicidal action of the extracts was evaluated in pre-emergence tests in cucumber (Cucumis sativus) seeds. The successful results indicated a high antifungal and herbicidal potential of the extracts obtained for both weeds, with the inhibitory effect against both fungi achieving up to 82%, and the inhibition of C. sativus seed germination reaching 100% for all samples. [ABSTRACT FROM AUTHOR]

Microbial lipids are a valuable source of potential biofuels and essential polyunsaturated fatty acids. The optimization of the fermentation conditions is a strategy that affects the total lipid concentration. The genus Nigrospora sp. has been the target of investigations based on its potential bioherbicidal action. Therefore, this study developed a strategy to maximize the biomass concentration and lipid accumulation by Nigrospora sp. in submerged fermentation. Different media compositions and process variables were investigated in shaken flasks and bioreactor in batch and fed-batch modes. Maximum biomass concentration and lipid accumulations were 40.17 g/L and 21.32 wt% in the bioreactor, which was 2.1 and 5.4 times higher than the same condition in shaken flasks, respectively. This study presents relevant information to the production of fungal lipids since few investigations are exploring the fed-batch strategy to increase the yield of fungi lipids, as well as few studies investigating Nigrospora sp. to produce lipids. [ABSTRACT FROM AUTHOR]

The use of hydrolyzed rice straw (HRS) and hydrolyzed rice husk (HRH) as feedstock for pyrolysis was evaluated through kinetic and thermodynamic studies. HRS and HRH were obtained from subcritical water hydrolysis (SWH) at different temperatures (180, 220, and 260°C). The Coats‐Redfern method was used to analyze the thermal behavior through thermogravimetry (TG) and derivative thermogravimetry (DTG) curves. TG profiles showed higher decomposition in the range of 250–400°C, especially for rice straw (RS) and HRS (80 wt %). The pyrolysis curves were well predicted by a first‐order reaction model. The kinetic analysis showed a variation in activation energy (EA) between 24.3 to 41.3 kJ mol−1 and 40.4 to 54.7 kJ mol−1 for RS/HRS and rice husk (RH)/HRH, respectively. The enthalpy (ΔH), Gibbs free energy (ΔG), and entropy (ΔS) varied from 25.9 to 39.6 kJ mol−1, 35.4 to 69.6 kJ mol−1, and −64.1 to −6.7 J mol−1 K−1, respectively, for RS/HRS, and 35 to 49.8 kJ mol−1, 43.2 to 79.3 kJ mol−1, and −53.5 to −10.2 J mol−1 K−1, respectively, for RH/HRH. These results showed that the pyrolysis reactivity using HRS is higher than HRH, which indicates the pyrolysis of HRS is more advantageous than HRH. [ABSTRACT FROM AUTHOR]