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Cell surface display of selenite reductase SerV01 in EcN enhanced Se(iv) reduction to achieve better selenium supplementation, selenoenzyme activity and intestinal flora in broilers.

Heavy metals (HMs) contaminated fish is a threat to humans when consumed. Dietary probiotics have evolved as a successful HMs removal approach. In this study, probiotics Enterococcus (EC) sp. and Lactococcus (LC) sp. were evaluated for toxicity alleviation and gut microbiota maintenance in Cyprinus carpio (single and combined approach) on Cr, Cd, and Cu mixture (0.8 mg/L and 1.6 mg/L) exposure (28 days). HMs removal, oxidative stress, cytokines response, histology, and gut microbiota were investigated. LC alone showed remarkable HMs removal for Cr (62.28%–87.57%), Cd (89%–90.42%), and Cu (72%–88%) than LC + EC. Probiotics up-regulated superoxide dismutase and total protein levels, while decreased the activity of malondialdehyde than the control. Pro-inflammatory cytokine (TNF-α) and chemokine (IL-8) expressions were higher at 1.6 mg/L concentration, whereas anti-inflammatory cytokine (IL-10) was higher in the 0.8 mg/L group. LC mitigated the histological alterations of gills, kidneys, and intestines, particularly at the lower concentration. Sequencing results revealed that Proteobacteria (44%–61%) was the most dominant phylum in all groups, followed by Fusobacteria (34%–36%) at 0.8 mg/L and Firmicutes (19%–34%) at 1.6 mg/L. The current study presented LC and EC potential separately and in combination to countermeasure HMs mixture induced toxicity and gut microbial dysbiosis, in which the conjoint group was less effective.

Biodiesel production from edible sources faces several challenges such as food security and cost issues. Waste cooking oils (WCOs) can be an alternative feedstock due to their large production. The comprehensive characterization of WCOs has been rarely reported in previous studies. In this study, six different WCOs including chicken oil (CO), fat, oil, and grease (FOG), beef hotpot oil (BHP), mixed waste cooking oil (MWO), duck oil (DO), and vegetable hotpot oil (VHP) were assessed for the biodiesel production. Lipid content of WCOs ranged from 73 to 84.5% with the highest C16 in DO (32.1%) and C18 in VHP (71.4%). The highest saturated (such as C16:0 and C18:0), monounsaturated (such as C18:1) and poly unsaturated (such as C18:2, and C18:3) fatty acids were 58%, 59%, and 21% in BHP, VHP, and MWO, respectively. The diverse nature of fatty acids in WCOs makes it highly recommended for biodiesel production, as its derived biodiesel complied with international standards. Fourier transform infrared spectroscopy confirmed the presence of linkages specific to lipid and thermogravimetric analysis showed high volatile matter content (>97%). Biochemical composition, fatty acids profile, and the properties of the produced biodiesel demonstrated that these WCOs could be promising candidates for biodiesel production, solving waste management and socio-economic challenges of conventional feedstocks. However, the commercialization of WCOs’ biodiesel requires further investigation of produced biodiesel and their petro-diesel blends on the engine performance, efficiency, and emissions (SO×, NO×, and CO×) parameters to produce quality and cost-effective biodiesel.

This paper aims to study the effect of Carbon Fiber Filament (CFF) with different ratios and lengths on the physical and mechanical properties of cement mortar. An experimental program included 3 cm fixed length of CFF with 0, 0.25, 0.5, 0.75, and 1% different ratios by weight of cement addition were used in cement mortar cubes. Another experimental program of 0.5% CFF ratio with 1, 2, 3, 4, and 5 cm different lengths by weight of cement addition was used in cement mortar prisms. The physical and mechanical properties of cement mortar containing CFF were experimentally investigated at 7 and 28 days of curing. Workability, by means of flow table test, were measured. Density is conducted for cubes and prisms at the age of 28 days. At ages of 7 and 28 days, compressive and flexural strengths were studied. The study showed a reduction in workability with the increase of CFF ratios and lengths by 0.0 to 2.7% and by 0.9 to 5.4% respectively. Moreover, an improvement in density, compressive, and flexural strengths was observed. At ages of 7 and 28 days, the results showed that compressive strength increased by 33 and 31% respectively at 0.5% of CFF ratio while the flexural strength increased by 125 and 327% respectively with CFF length of 5 cm. Doi: 10.28991/cej-2021-03091753 Full Text: PDF

The presence of heavy metals (HMs) in aquatic ecosystems is a universal concern due to their tendency to accumulate in aquatic organisms. HMs accumulation has been found to cause toxic effects in aquatic organisms. The common HMs-induced toxicities are growth inhibition, reduced survival, oxidative stress, tissue damage, respiratory problems, and gut microbial dysbiosis. The application of dietary probiotics has been evolving as a potential approach to bind and remove HMs from the gut, which is called "Gut remediation". The toxic effects of HMs in fish, mice, and humans with the potential of probiotics in removing HMs have been discussed previously. However, the toxic effects of HMs and protective strategies of probiotics on the organisms of each trophic level have not been comprehensively reviewed yet. Thus, this review summarizes the toxic effects caused by HMs in the organisms (at each trophic level) of the aquatic food chain, with a special reference to gut microbiota. The potential of bacterial probiotics in toxicity alleviation and their protective strategies to prevent toxicities caused by HMs in them are also explained. The dietary probiotics are capable of removing HMs (50-90%) primarily from the gut of the organisms. Specifically, probiotics have been reported to reduce the absorption of HMs in the intestinal tract via the enhancement of intestinal HM sequestration, detoxification of HMs, changing the expression of metal transporter proteins, and maintaining the gut barrier function. The probiotic is recommended as a novel strategy to minimize aquaculture HMs toxicity and safe human health.

This study evaluates the effect of substituting cement by volcanic tuff on the workability, mechanical properties, and durability of concrete. Five mixtures were prepared with volcanic tuff ratios to cement of 0%, 5%, 10%, 15% and 20%. First, X-Ray Fluorescence (XRF) test for volcanic tuff was performed. Then, slump test was conducted for fresh concrete specimens. Moreover, tests for flexural strength, splitting tensile strength, elevated heat resistance, ultrasonic pulse velocity, and Scanning Electron Microscope (SEM) were performed at 28-days age of concrete specimens. Compressive strength, and absorption tests were conducted at 28, and 56-days ages of specimens. The study showed that slump, compressive strength, flexural strength, and splitting tensile strength were decreased with the increasing of volcanic tuff to cement replacement ratio at 28-days age. Additionally, the highest compressive strength and lowest water absorption for concrete were obtained at 56-days age of specimens and 10% volcanic tuff to cement replacement ratio.

Cancer is a vital barrier to increase the life expectancy and the foremost cause of death globally. The initial diagnosis and proper management of cancer can expand the survival rate of individuals. This review provides an in-depth investigation of cancer causes symptoms, types of cancer, and worldwide distribution of cancer. The relation between nutrition (i.e., various food items) and cancer is also emphasized to offer a framework of nutrition management in different cancer types. The microbiota is closely associated with the occurrence of cancer. Thus, genomics of intestinal microbes and nutrigenomics have been discussed based on the reported meta-analysis studies. A dramatic increase in cancer rates has been observed due to intake of alcohol, microbial infections, and deficiency of nutrition. Malnutrition is a substantial problem in cancer patients linked with improper treatment and increased morbidity. The detail studies of cancer and nutrigenomics are an eminent approach to comprehend the relation between microbes and the consumption of certain food types which can further reduce the cancer risk. The incorporation of specific nutrients and probiotics improved the gut microbial health, increased life expectancy, and also decreased the incidence of tumorigenesis in individuals.

This study aims to determine the environmental impacts and feasibility of optimizing the production of phenolic-rich bio-oil, via switchgrass microwave catalytic pyrolysis. K3PO4 (Tripotassium phosphate) was used as the catalyst, at different temperatures, throughout this life cycle assessment (LCA) study. Results were compared with non-catalytic microwave pyrolysis (SiC-400) and conventional pyrolysis. K3PO4 (KP) was used as the microwave absorber and catalyst to enhance the low microwave absorption of switchgrass during microwave pyrolysis, and to improve the bio-oil quality and selectivity for phenolics production. Pyrolysis temperatures made a considerable difference to the LCA. There was an 86% reduction in the pyrolysis time when heating the sample to 300 °C (KP-300), as compared to 400 °C (KP-400), resulting in a significant reduction of the amount of energy required, and GHG's emitted. The total global warming potential (GWP) for microwave catalytic pyrolysis is observed within 159–223 kg CO2-eq/1000 kg of dried switchgrass (SG), with the baseline case (SiC-400) being the highest, and KP-300 being the lowest. Using the produced biochar, which is rich in nutrients for soil application, brings the net GWP to negative values through carbon sequestration. KP-300 also showed the highest selectivity for phenol and alkylphenols production, which increased by 252% and 420% respectively, compared to the baseline. The results clearly indicate that introducing K3PO4 showed great potential for accelerating microwave heating, and improving bio-oil selectivity towards alkylphenols, which can be used to replace petroleum-based phenol. This in turn can reduce GHG emissions, due to higher conversion efficiencies and lower energy consumption compared with non-catalytic microwave pyrolysis and conventional pyrolysis.

The dibutyl phthalate (DPB) is an emerging plasticizer contaminant that disrupts the biological processes of primary producers, especially phytoplankton. In this study, two microalgal species (Chlorella sp. GEEL-08 and Tetradesmus dimorphus GEEL-04) were exposed to various concentrations of DBP extending from 0 to 100 mg/L. The growth kinetics, N-nitrate, and P-phosphate removal efficiency were assessed. The response enzymes such as malonaldehyde (MDA) and superoxide dismutase (SOD) were also investigated. The results revealed that the Chlorella sp. GEEL-08 at 10 mg/L concentration of DBP exhibited higher growth (0.88 OD

Lignocellulosic biomass is a highly available and suitable candidate for biogas/biomethane production. However, high concentration of recalcitrant lignin is the major obstacle in successful anaerobic digestion (AD). The main aim of this review is to highlight the applications and challenges of lignocellulosic biomass in AD from the recent reports. Potential approaches to improve instabilities in mesophilic AD process (such as microbial communities' development, co-digestion, biofilm carrier's addition, and essential nutrients supplement) were also reported. This review goes one more step deeper to discuss the key microbes involved in lignocellulosic biomass degradation. Biofilm carriers provide attached growth systems for microbes in AD and acts as redox mediators to accelerate the biotransformation of recalcitrant pollutants. Addition of nanoparticles (NPs) stimulate Firmicutes, Bacteroidetes, Methanosaeta, Methanobacterium, and Methanosarcina population which further improve biomethanation. The comprehensive study of these proposed strategies and microbial stimulation through additives would make the lignocellulosic biomethanation more feasible. (c) 2021 Society of Chemical Industry (SCI).

Emergence of pollutants in wastewater, expensive cultivation of microalgae, and difficulties in industrial scale production are the main challenges for successful coupling of microalgae with wastewater. Nitrogen, carbon, and phosphorus in wastewater are deliberately consumed by microalgae and cyanobacteria for their growth and could act as green technology for wastewater treatment. In this review, the role and mechanistic approaches of microalgae and cyanobacteria for removal of various (in)organic compounds from wastewater have been thoroughly addressed. Distinct pathways have been reported for improving wastewater treatment technologies through large-scale cultivation of microalgal. The techno-economic feasibility and major commercial production challenges along with genetic engineering research have been addressed. A biorefinery approach with integrated biology, ecology, and engineering would lead to a feasible microalgal-based technology for various applications.

A comprehensive bio-composition investigation of microalgal species is essential for categorizing their applications. In this study, nutrients uptake followed by complete biomass characterizations, including proximate, ultimate, and bio-compounds (proteins, carbohydrates, and lipids), were performed along with FTIR and TGA/DTG, analyses of four microalgal strains (Tetradesmus dimorphus GEEL-06, Tetradesmus obliquus GEEL-07, Chlorella sp. GEEL08, and Chlorella sorokiniana GEEL-09). All microalgae species were able to remove 90%–95% nitrogen and phosphorus. T. dimorphus GEEL-06 had highest growth with proteins accumulation of 36.63% and 28.33% of lipids. T. obliquus GEEL-07, Chlorella sp. GEEL08, and C. sorokiniana GEEL-09 accumulated 46.37%, 31.13%, and 39.38% of proteins and 27.94%, 34.61%, and 36.56% of carbohydrates, respectively. FTIR spectra revealed the presence of an alcohol, carboxyl, and amino groups, while biomass pyrolysis showed 67%–80% decomposition. Biodiesel feasibility was confirmed by the presence of 68%–84% C16/C18. These results indicate the potential applications of T. obliquus GEEL-07, C. sorokiniana GEEL-09, and T. dimorphus GEEL-06/Chlorella sp. GEEL08 for production of higher alcohols, bioethanol, biodiesel/oil for, respectively, along with nutrients removal.

Isolation and screening of microalgal species from natural habitats should be a continues work to discover effective species for biofuel generation and wastewater treatment. In the current study, microalgal species namely Tetradesmus dimorphus GEEL-04 and Desmodesmus asymmetricus GEEL-05 were isolated, identified, and assessed for growth kinetics, nutrients removal efficiency, and whole biomass composition. T. dimorphus showed higher growth (1.46 OD680nm) compared with D. asymmetricus (1.16 OD680nm), and both showed 99% total nitrogen and total phosphorous removal. T. dimorphus and D. asymmetricus accumulated higher protein content (40.02 and 45.10%), carbohydrate (31.91 and 24.64%), and lipid (15.41 and 24.16%), respectively. The FTIR spectra absorbance revealed different function groups in microalgal biomass available for biofuel generation. Elemental analysis of microalgal biomass showed high carbon content 50.13% and 43.01% for T. dimorphus and D. asymmetricus, respectively. Thermogravimetric analysis indicated ≥ 80% volatile content in both isolates. The fatty acid composition of both microalgal strains showed high palmitic acid and linoleic acid corresponding to high quality biodiesel. These results indicated that the T. dimorphus and D. asymmetricus could be potential candidates for high biocomponents accumulation and N, P removal.

Wastewater utilization as a medium for microalgal cultivation have copious simultaneous perquisites such as removal of nutrients (80–100%), heavy metal removal, carbon dioxide (CO2) sequestration from atmosphere (1.83 kg CO2 kg−1 biomass), and high biomass production for biofuel generation (40–50% higher than crops feedstock). Municipal, industrial, domestic, agro-industrial, and several other types of wastewater treatment by coupling microalgal cultivation require two sorts of systems: open pond systems (OPs) and closed photobioreactors (PBRs). Many studies have focused on the utilization of OPs and closed PBRs for microalgal cultivation; however, comprehensive information in context of nutrient removal efficiency and biomass productivity with updated data is not fully addressed. In this review, wastewater treatment coupled microalgal cultivation for biofuel generation is emphasized in OPs and closed PBRs. The limitations of both systems, implementation of different approaches to enhance the biomass productivity, and economic feasibility are also highlighted. Based on the literature analysis, PBRs are more effective in wastewater treatment and biomass/biofuel generation due to contamination control and management of major parameters affecting microalgal growth. However, the implementation of various techniques to reduce the capital investment in PBR reactor designs is required for further use on commercial scale.

Two types of plastic carriers low-density polyethylene (LDPET) and high-density polyethylene (HDPET) were used as a support material for biofilm formation during anaerobic co-digestion of agricultural wastes. LDPET and HDPET were added separately to different reactors containing binary substrates: corn straw and cauliflower leaves (G 1), corn straw and cow dung (G 2), while ternary substrates corn straw, cauliflower leaves, and cow dung were used in G 3. Reactors containing either HDPET or LDPET carriers supported the enhancement of biogas and biomethane. Maximum daily biomethane (333.43 and 368.35 mL/day) was achieved after HDPET addition to G1 and G2 at day 10 and 12, respectively. The accumulative biomethane were significantly enhanced (p

This study was designed to isolate microalgal species which can tolerate severe environmental stresses and can be used for wastewater treatment and biofuel generation. Three different microalgal strains (including Chlorella sorokiniana GEEL-01, Parachlorella kessleri GEEL-02, and Parachlorella kessleri GEEL-03) were isolated from a wastewater treatment plant and Waterwheel Park. The highest growth rate (1.61 OD680nm) was observed for C. sorokiniana GEEL-01 with highest removal of total nitrogen (1.5 mg L−1 day−1) and total phosphorus (1.82 mg L−1 day−1). The biocomponents of the isolated species ranged from 19.47–29.64%, 39.39–52.51%, and 15.08–22.75% for carbohydrate, protein, and lipid, respectively, based on the dry cell weight (DCW). The function groups in microalgal biocompounds were also confirmed by Fourier-transform infrared radiation (FT-IR) spectra, indicated their ability for biofuel generation. Ultimate and proximate analyses of C. sorokiniana GEEL-01 showed high carbon (54.24% DCW) and volatile content (92.69% DCW), compare to other strains. Moreover, it exhibited a significant accumulation of lipid with an increase in the fractions of saturated fatty acids (64.5%), and the major fatty acids were palmitic acid (11.17%), stearic acid (33.86%), oleic acid (9.84%), and linoleic acid (11.56%). Biodiesel derived from the major fatty acids had optimum engine efficiency properties including iodine value (77.34 g I2/100 g oil) and cetane number (54.83). Cultivation of C. sorokiniana GEEL-01 can serve as a dual function of biodiesel feedstock generation and nutrients removal.