Engineering strategies of microalgal cultivation for potential jet fuel production – A critical review

The aviation industry stands as a well-known "hard to electrify" sector, currently responsible for the consumption of massive amounts of fossil fuels, considerably contributing to global CO2 emissions. The need to reduce the aviation carbon footprint to comply with the European Green Deal objectives, has driven intensive research into the so-called bio-jet fuels (BJF) that can be obtained from different lipid-rich substrates, including microalgae among the most promising. Starting from the analysis of existing studies dealing with the selection of the strains more indicated for BJF production, this review examines the most recent breakthrough in microalgae cultivation techniques and lipid accumulation strategies, focusing on the approaches targeting the enhancement of the process environmental sustainability. The main bottlenecks in each phase of the production process are identified and critically reviewed. The most recent solutions are also thoroughly discussed to point out room for improvements in consolidated engineering strategies, as well as areas of further scientific research to advance the state of the art on micro-algal potential for BJF production

A Comparative Study of the Antibacterial, Antifungal and Antioxidant Activity and Total Content of Phenolic Compounds of Cell Cultures and Wild Plants of Three Endemic Species of Ephedra

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)

A Comparative Study of the Antibacterial, Antifungal and Antioxidant Activity and Total Content of Phenolic Compounds of Cell Cultures and Wild Plants of Three Endemic Species of

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Microplastics and their interactions with microbiota

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

The effect of probiotics on health status and performance of Holstein calves

The positive effect of probiotics on performance and health status of suckling calves has long been demonstrated. Probiotics are a group of living microorganisms used in livestock feeding, These additives not only have no harmful effects to living organisms, but secrete various enzymes which break down organic carbon chains and produce substances such as sugars, alcohols, vitamins and other nutrients. In order to carry out the present study, 24 male and female calves with an average weight of 50±3 kg and age of 40±3 days were selected for an experimental period of 45 days. The treatments included consisted of, 1- control group, 2- the group receiving Lactobacillus casei and 3- the group receiving Lactobacillus acidophilus. The probiotics were given to calves along withphysiological saline solution. The use oflactobacilli had no significant effect on feed intake although their supplementation increased the weight of the calves during the entire period (ppp<0.05). Inversely, no significant effect on the amount of total protein, albumin, triglycerides and blood cholesterol was shown. Furthermore, the results showed that probiotic supplements improved health indicators numerically but not statistically. According to the results, it can be concluded that supplementation of probiotics in the diet of calves improves performance and has a beneficial effect on some blood parameters

Application of carrot waste extract and Lactobacillus plantarum in Alyssum homalocarpum seed gum-alginate beads to create a functional synbiotic yogurt

Abstract One of the most recent and effective methods, which is currently receiving special attention and is being developed by numerous researchers, is production of microspheres from the probiotic cells. The largest market segment for functional foods is represented by dairy products, which have been touted as the most effective carriers of nutrients, such as probiotics, prebiotics, proteins, vitamins, and minerals. Yogurt is fermented dairy product that is popular all over the world. A new functional symbiotic yogurt fabricated by plant wastes (carrot pomace extract), Lactobacillus plantarum, and beads based on Alyssum homolocarpum seed gum (AHSG) and sodium alginate (SA) using extrusion technique was produced and characterized. Evaluation of the functional properties of yogurts indicated that the total phenolic content and DPPH radical scavenging activity were in the range of 16.13–48.30 µg GAE/ml and 7.4–14.64%, respectively. The acidity, pH, syneresis, water holding capacity, lightness, redness, and yellowness of the yogurts were in the range of 1.50–2.90, 4.07–4.38, 49.00–57.24%, 46.8–57.3%, 57.16–61.25, − 0.20–0.91, 6.40–13.06 on the 28th day storage, respectively. The panelists confirmed the sensory properties of yogurt samples. Probiotic survival rate of the functional yogurts were in the range of 6.37–8.13 log CFU/g, on the 28th day. Based on the results, bead production by AHSG and SA and the use of carrot pomace extract enhanced the survival of probiotic bacteria significantly in yogurt during storage compared to free cells. Graphical Abstrac

Effect of three methods of estrus synchronization: Osynch, Co-Synch and Prostaglandin on the fertility of subfertile dairy cows

This study was performed to compare the effect of using 3 different estrus synchronization methods (Ovsynch, Co-Synch and Prostaglandin) on the conception rate of subfertile dairy cows. Fifty one subfertile Holstein dairy cows with parity ranging from 1 to 7 were enrolled in this study. Cows were allocated to three groups Ovsynch (n=10), Co-Synch (n=27) and Prostaglandin (n=14). Cows in the Ovsynch group underwent a standard Ovsynch protocol (GnRH analogue on Day 0, PGF2α analogue on Day 7 and GnRH analogue on Day 9), then they were artificially inseminated approximately 16 hours after the second GnRH treatment. The same procedure was done for cows in Co-Synch group, but artificial insemination took place immediately after the last injection. Cows in prostaglandin group underwent a PG protocol (PGF2α, on Day 0 and 12), and artificial insemination was done about 72 hours after the second PGF2α injection. Pregnancy diagnosis was performed 60 days after insemination via rectal examination. By using logistic procedure of SAS 9.1 software, the effects of treatment, season, parity, animal, age and open days were analyzed. The analysis of variables related to animal and the measured effects on pregnancy proved that none of the evaluated parameters were significant. Hence, we cannot declare which of the estrus synchronization methods is suitable to increase pregnancy rate. Further studies with more replicates are required to choose the best method