Bioremediation strategies against pesticides: an overview of current knowledge and innovations.

Pesticides pose significant risks to both human health, such as cancer, neurological disorders, and endocrine disruption, and ecosystems, through the destruction of beneficial insects, contamination of soil and water, and impact on non-target species. In the face of escalating pesticide pollution, there is an urgent need for multifaceted approaches to address the issue. Bioremediation emerges as a potent tool in the environmental pollution mitigation arsenal. Ideally aiming for the complete decomposition of pesticides into harmless molecules, bioremediation encompasses diverse approaches - from bioabsorption, bioadsorption, and biotransformation using enzymes and nanoenzymes to comprehensive degradation facilitated by microorganisms such as bacteria, fungi, macro- and microalgae, or phytoremediation. Exploring nature's biodiversity offers a promising avenue to find solutions to this pressing human-induced problem. The acceleration of biodegradation necessitates identifying and developing efficient organisms, achieved through bioprospection and targeted modifications. Specific strategies to enhance process efficiency and throughput include optimizing biomass production, strategic inoculation in diverse environments, and employing bioreactor systems for processing heavily contaminated waters or soils. This comprehensive review presents various bioremediation approaches, emphasizing the importance of microorganisms' exploration and new technologies development, including current innovations and patents to effectively combat pesticide pollution. Furthermore, challenges regarding the effective implementation of these technologies are also addressed.

Polyhydroxyalkanoates production in biorefineries: A review on current status, challenges and opportunities.

The need for a sustainable and circular bioeconomy model is imperative due to petroleum non-renewability, scarcity and environmental impacts. Biorefineries systems explore biomass to its maximum, being an important pillar for the development of circular bioeconomy. Polyhydroxyalkanoates (PHAs) can take advantage of biorefineries, as they can be produced using renewable feedstocks, and are potential substitutes for petrochemical plastics. The present work aims to evaluate the current status of the industrial development of PHAs production in biorefineries and PHAs contributions to the bioeconomy, along with future development points. Advancements are noticed when PHA production is coupled in wastewater treatment systems, when residues are used as substrate, and also when analytical methodologies are applied to evaluate the production process, such as the Life Cycle and Techno-Economic Analysis. For the commercial success of PHAs, it is established the need for dedicated investment and policies, in addition to proper collaboration of different society actors.

Polyhydroxybutyrate production by Cupriavidus necator in a corn biorefinery concept.

The high costs of bioplastics' production may hinder their commercialization. Development of new processes with high yields and in biorefineries can enhance diffusion of these materials. This work evaluated the production of polyhydroxybutyrate (PHB) from the combination of milled corn starchy fraction hydrolysate and crude glycerol as substrates by the strain Cupriavidus necator LPB 1421. After optimization steps, maximum accumulation of 62 % of PHB was obtained, which represents 11.64 g.L-1 and productivity of 0.162 g.Lh-1. In a stirred tank bioreactor system with 8 L of operational volume, 70 % of PHB accumulation was reported, representing 14.17 g.L-1 of the biopolymer with 0.197 g.Lh-1 productivity. PHB recovery was conducted using a chemical digestion method, reaching >99 % purity. Therefore, the potential application of milled corn as substrate for PHB production was confirmed. The developed bioplastic process could be coupled to a bioethanol producing unit creating the opportunity of a sustainable and economic biorefinery.

Citric acid bioproduction and downstream processing: Status, opportunities, and challenges.

Citric acid (CA) has been widely used in different industrial sectors, being produced through fermentation of low-cost feedstock. The development of downstream processes, easier to operate, environmentally friendly, and more economic than precipitation, is certainly a challenge in CA bioproduction. Large volumes of by-products generated in precipitation require treatment before disposal. Adsorption, extraction, and membrane separation have been shown to have a lower environmental impact than precipitation, but the technological maturity of these methods is still limited. However, reactive extraction and adsorption have great potential for industrial applications. This review shows that there is still much to be explored, both about the factors that are intrinsic to the techniques, but also in their combination for new processes' development. This review reports the most recent advances on CA bioproduction, with significant information about recovery and purification methods involving this highly industrially demanded organic acid.