As a new pollutant, Microplastics (MPs) are globally known for their negative impacts on different ecosystems and living organisms. MPs are easily taken up by the ecosystem in a variety of organisms due to their small size, and cause immunological, neurological, and respiratory diseases in the impacted organism. Moreover, in the impacted environments, MPs can release toxic additives and act as a vector and scaffold for colonization and transportation of specific microbes and lead to imbalances in microbiota and the biogeochemical and nutrients dynamic. To address the concerns on controlling the MPs pollution on the microbiota and ecosystem, the microbial biodegradation of MPs can be potentially considered as an effective environment friendly approach. The objectives of the presented paper are to provide information on the toxicological effects of MPs on microbiota, to discuss the negative impacts of microbial colonization of MPs, and to introduce the microbes with biodegradation ability of MPs.

Investigations were carried out to determine antimicrobial and antioxidant properties and total phenol content of three wild species of Ephedra compared with their respective callus cultures. Callus induction was performed in a standard Murashige and Skoog (MS) medium with the following hormonal ranges (mg/L) for every species NAA:1.5, Kin:1 for Ephedra strobiliacea, NAA:2, Kin:1 for Ephedra procera and NAA:2, Kin:0.5 for Ephedra pachyclada. These ranges of PGPR (Plant Growth Promote Regulators) were chosen based on callus induction rates, RGR (Relative Growth Rate) and their fresh weights. An antimicrobial test against five Gram negative and two Gram positive bacteria and two fungi was performed using the disc diffusion method. All methanolic extracts showed antimicrobial activity, but the antimicrobial activity of the callus cultures was lower than those of the wild plants. E. strobilacea showed the highest antimicrobial activity, and all methanolic extracts of the wild plants and callus cultures unexpectedly showed the highest antimicrobial activity against Pseudomonas aeruginosa. A FRAP (Ferric Reducing Antioxidant Power) test was conducted to evaluate extracts for antioxidant activity. E. strobilacea with 1.61 ± 0.08 mmol eq quercetin/gextract and 0.278 ± 0.02 mmol eq quercetin/gextract for the wild plant and callus, respectively, showed the highest results.The total phenol content of extracts was measured by a Folin Ciocalteau test. All the chosen species displayed phenol contents but E. strobilacea had the highest amount (504.9 ± 41.51 μmol eq catechin/gextracts and 114.61 ± 15.13 μmol eq catechin/gextracts for the wild plants and callus, respectively).

Photoautotrophic microalgae are a promising avenue for sustained biodiesel production, but are compromised by low yields of biomass and lipids at present. We are developing a chemical approach to improve microalgal accumulation of feedstock lipids as well as high-value alpha-linolenic acid which in turn might provide a driving force for biodiesel production. We demonstrate the effectiveness of the small bioactive molecule “acetylcholine” on accumulation of biomass, total lipids, and alpha-linolenic acid in Chlorella sorokiniana. The effectiveness exists in different species of Chlorella. Moreover, the precursor and analogs of acetylcholine display increased effectiveness at higher applied doses, with maximal increases by 126, 80, and 60% over controls for biomass, total lipids, and alpha-linolenic acid, respectively. Production of calculated biodiesel was also improved by the precursor and analogs of acetylcholine. The biodiesel quality affected by changes in microalgal fatty acid composition was addressed. The chemical approach described here could improve the lipid yield and biodiesel production of photoautotrophic microalgae if combined with current genetic approaches.

• CRISPR-Cas systems offer a flexible and easy-to-use molecular platform to precisely modify and control organisms' genomes in a variety of fields, from agricultural biotechnology to therapeutics. • With CRISPR technology, crop genomes can be precisely edited in a shorter and more efficient approach compared to traditional breeding or classic mutagenesis. • CRISPR-Cas system can be used to manage the fermentation process by addressing phage resistance, antimicrobial activity, and genome editing. • CRISPR-Cas technology has opened up a new era in gene therapy and other therapeutic fields and given hope to thousands of patients with genetic diseases. • Anti-CRISPR molecules are powerful tools for regulating the CRISPR-Cas systems.