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In this study, the antibacterial and antibiofilm properties of pomegranate (Punica granatum L.) extracts (PPLs) prepared by 10g of pomegranate peels (PPL10) and 100 mL of different solvents (ethanol, methanol, and their acid combinations, and water) were investigated as sources of bioactive compounds against food related bacteria. The antimicrobial activities of the extracts were measured by using agar well diffusion assay. The acid-treated extracts exhibited the highest antimicrobial activities (31-34 mm). The biofilm formations were assessed by using a microplate reader (570 nm) after crystal violet staining. The prevention and removal of bacterial biofilms were also evaluated by using extracts prepared by 5g of initial pomegranate peel (PPL5) with the different solvents or 200 ppm chlorine solution. All PPL5 and PPL10 extracts diluted at different ratios inhibited and removed biofilms and the highest antibiofilm effects were up to 80% by acid-treated extracts. In addition, PPL5s and PPL10s were as effective as or more effective than chlorine for the prevention of biofilms. Therefore, from an economical perspective the PPL5s could represent promising candidates as natural antibiofilm agents for food industry.

Fish processing towards production of fillet gives rise to wastewater streams that are ultimately directed to biogas production and/or wastewater treatment. However, these wastewater streams are rich in minerals, fat, and proteins that can be converted to protein-rich feed ingredients through submerged cultivation of edible filamentous fungi. In this study, the origin of wastewater stream, initial pH, cultivation time, and extent of washing during sieving, were found to influence the amount of recovered material from the wastewater streams and its protein content, following cultivation with Aspergillus oryzae. Through cultivation of the filamentous fungus in sludge, 330 kg of material per ton of COD were recovered by sieving, corresponding to 121 kg protein per ton of COD, while through its cultivation in salt brine, 210 kg of material were recovered per ton of COD, corresponding to 128 kg protein per ton of COD. Removal ranges of 12–43%, 39–92%, and 32–66% for COD, total solids, and nitrogen, respectively, were obtained after A. oryzae growth and harvesting in the wastewater streams. Therefore, the present study shows the versatility that the integration of fungal cultivation provides to fish processing industries, and should be complemented by economic, environmental, and feeding studies, in order to reveal the most promising valorization strategy.

Olive oil mills represent an important sector in the Mediterranean Sea Basin but also an environmental hazard due to untreated wastewater. Recovery of nutrients from olive oil mill wastewater(OMWW)as protein-rich microbial biomass can produce novel feed and reduce its chemical oxygen demand; however, low-protein containing products have been reported. New strategies leading to higher protein-containing fungal biomass could renew the research interest on bioconversion for pollution mitigation of OMWW. In this work, through cultivation of edible filamentous fungi(Aspergillus oryzae, Neurospora intermedia, and Rhizopus delemar), a link between the protein content inthe originated fungal biomass, and the addition of nitrogen and medium dilution was established. Addition of nitrogen in the form of NaNO3 reduced the cultivation time from 96 h to 48 h while achieving a similar biomass mass concentration of 8.43 g/L and increased biomass protein content, from w = 15.9% to w = 29.5%. Nitrogen addition and dilution of OMWW, and consequent reduction of suspended solids, led to an increase in the protein content to up to w = 44.9%. To the best of our knowledge, the protein contents achieved are the highest reported to date and can open new research avenues towards bioconversion of OMWW using edible filamentous fungi.

In this research, 15 meteorological stations located in western Anatolia in Turkey were investigated for determining temperature properties. The vegetation season has been determined according to days when the daily temperature was greater than or equal to 8°C. The research area has 3 different vegetation durations as longer (more than 225 days in the western and southern parts), moderate (210-220 days in plateaus around Uşak, Gediz and Demirci), and shorter (180-195 days in the eastern part and less than 180 days in mountainous areas). Then, the vegetation has been reinvestigated according to climate change scenarios (RCP 4.5 and 8.5). For this purpose, the daily mean temperatures were raised by 2.6°C and 4.8°C for RCP 4.5 and RCP 8.5, respectively. In the reinvestigation period, the vegetation period will increase about 15-20 days or over 40 days according to RCP 4.5 and 8.5, respectively. Along with the increase in temperature throughout the research area, growing seasons will be significantly affected, beginning and ending dates of vegetation would shift. Owing to climate change effects, mountainous areas may be affected more than low-altitude areas. As a conclusion due to the result of increasing temperature, plant development and distribution will be affected, and new plant species may occur

This study describes an efficient and reusable process for ethanol production from medium containing whey powder, using alginate immobilized ethanologenic E. coli strains either expressing (TS3) or not expressing (FBR5) Vitreoscilla hemoglobin. Reuseabilities of the FBR5 and TS3 strains were investigated regarding their ethanol production capacities over the course of 15 successive 96-h batch fermentations. The ethanol production was fairly stable over the entire duration of the experiment, with strain TS3 maintaining a substantial advantage over strain FBR5. Storage of both strains in 2 different solutions for up to 60 d resulted in only a modest loss of ethanol production, with strain TS3 consistently outperforming strain FBR5 by a substantial amount. Strains stored for 15 or 30 d maintained their abilities to produce ethanol without dimunition over the course of 8 successive batch fermentations; again strain TS3 maintained a substantial advantage over strain FBR5 throughout the entire experiment. Thus, immobilization is a useful strategy to maintain the advantage in ethanol productivity afforded by expression of Vitreoscilla hemoglobin over long periods of time and large numbers of repeated batch fermentations, including, as in this case, using media with food processing wastes as the carbon source.

Ethanol production from whey powder was investigated by using free as well as alginate immobilized E. coli and E. coli expressing Vitreoscilla hemoglobin (VHb) in both shake flask and fermenter cultures. Media with varying levels of whey (lactose contents of 3%, 5%, 8% or 15%) and yeast extract (0.3% or 0.5%) were evaluated with fermentation times of 48–96 h. Immobilization and VHb expression resulted in higher ethanol production with all media; the increases ranged from 2% to 89% for immobilization and from 2% to 182% for VHb expression. It was determined that growth medium containing 8% lactose with 0.5% yeast extract yielded the highest ethanol production for free or immobilized strains, with or without VHb expression, in both shake flask and fermenter cultures. Immobilization with alginate was found to be a promising process for ethanol production by VHb-expressing ethanologenic E. coli.