Microalgal species are potential resource of both biofuels and high-value metabolites, and their production is growth dependent. Growth parameters can be screened for the selection of novel ...microalgal species that produce molecules of interest. In this context our review confirms that, autotrophic and heterotrophic organisms have demonstrated a dual potential, namely the ability to produce lipids as well as value-added products (particularly carotenoids) under influence of various physico-chemical stresses on microalgae. Some species of microalgae can synthesize, besides some pigments, very-long-chain polyunsaturated fatty acids (VL-PUFA,>20C) such as docosahexaenoic acid and eicosapentaenoic acid, those have significant applications in food and health. Producing value-added by-products in addition to biofuels, fatty acid methyl esters (FAME), and lipids has the potential to improve microalgae-based biorefineries by employing either the autotrophic or the heterotrophic mode, which could be an offshoot of biotechnology. The review considers the potential of microalgae to produce a range of products and indicates future directions for developing suitable criteria for choosing novel isolates through bioprospecting large gene pool of microalga obtained from various habitats and climatic conditions.
Mycorrhizal biotechnology has emerged as a major component of sustainable agriculture and allied activities. Innovations related to its role in agriculture, land reclamation, forestry, and ...landscaping are well recognized. This review presents the evolution of innovations worldwide related to arbuscular mycorrhizal fungi (AMF) in the past two decades, from 2000 to April 2020, and maintains that such innovations must continue in the future. An analysis of 696 patents showed that AMF have been used consistently as a biofertilizer and bioremediator over that period, although an upsurge was noted in propagation technologies, next-generation production methods, and formulation technologies. This review will familiarize mycorrhizologists with novel and evolving trends and will convince them of the importance of applying for patents to safeguard their innovations and the use of those innovations by industry.
Abstract
Genetic components that regulate arbuscular mycorrhizal (AM) interactions in hosts and non-hosts are not completely known. Comparative transcriptomic analysis was combined with phylogenetic ...studies to identify the factors that distinguish AM host from non-host. Mycorrhized host, non-mycorrhized host and non-host cultivars of tomato (
Solanum lycopersicum
) were subjected to RNA seq analysis. The top 10 differentially expressed genes were subjected to extensive in silico phylogenetic analysis along with 10 more candidate genes that have been previously reported for AM-plant interactions. Seven distantly related hosts and four non-hosts were selected to identify structural differences in selected gene/protein candidates. The screened genes/proteins were subjected to MEME, CODEML and DIVERGE analysis to identify evolutionary patterns that differentiate hosts from non-hosts. Based on the results, candidate genes were categorized as highly influenced (SYMRK and CCaMK), moderately influenced and minimally influenced by evolutionary constraints. We propose that the amino acid and nucleotide changes specific to non-hosts are likely to correspond to aberrations in functionality towards AM symbiosis. This study paves way for future research aimed at understanding innate differences in genetic make-up of AM hosts and non-hosts, in addition to the theory of gene losses from the “AM-symbiotic toolkit”.
The tannery industry process involves chromium (Cr) salts as a main constituent of the process. The Cr recovery is a part of the process where other salts are used to achieve separation and recovery ...for using Cr back in the process. The process steps may contain both forms of Cr Cr(VI): hexavalent and Cr(III): trivalent. The recovery of Cr from tannery industry effluent through biological systems is much needed. The diverse physicochemical characteristics of these effluents may limit the growth of microorganisms and hence the limitation towards possible practical application of microorganisms in real industrial effluent conditions. The present study attempted the ability of the Cr-resistant fungus Paecilomyces lilacinus isolated through an enrichment culture technique at 25 000 mg l−1 of Cr(III) to grow and remove Cr Cr(VI) and Cr(III) from two physicochemically different undiluted tannery industry effluents (tannery effluent and spent chrome effluent) in the presence of cane sugar as a carbon source. Such attempts are made keeping in view the potential integration of biological processes in the overall Cr removal and recovery processes to improve its efficiency and environmental sustainability. The fungus has broad pH tolerance range and can reduce Cr(VI) both in acidic (pH 5.5) and alkaline (pH 8.0) conditions. The fungus showed the ability to remove Cr(VI) (1.24 mg l−1) and total Cr (7.91 mg l−1) from tannery effluent below the detection level within 18 h and 36 h of incubation, respectively, and ability to accumulate 189.13 mg Cr g−1 of dry biomass within 600 h of incubation from spent chrome effluent containing 3731.4 mg l−1 of initial Cr(III) concentration.
At 200 mg l−1 of Cr(VI) in growth media, with 100% detoxification and with only 10.54% of total Cr accumulation in the biomass, P. lilacinus showed Cr(VI) reduction as a major mechanism of Cr(VI) detoxification. The time-course study revealed the log phase of the growth for the maximum specific reduction of Cr(VI) and stationary phase of the growth for its maximum specific accumulation of both the forms of Cr Cr(III) and Cr(VI) in its biomass. In growth media at 50 mg l−1 and 200 mg l−1 of Cr(VI), P. lilacinus showed 100% reduction within 36 h and 120 h of incubation, respectively. The high degree of positive correlation and statistically high degree of relationship (r2 = 0.941) between the fungal growth and % Cr(VI) reduction by the fungus support the role of metabolically active cellular growth in Cr(VI) reduction by the fungus. Results indicate that expanded solid (sludge) retention times (SRTs) (stationary phase) can be recommended for the removal of Cr(III) through accumulation. In case of Cr(VI), reduction needs a priority; therefore, a non-expanded SRT is recommended for designing a continuous-flow completely stirred bioreactor so that a log phase of cellular growth can be maintained during the reduction process. This study reveals the strong potential of P. lilacinus fungi for the removal of Cr from tannery effluent and spent chrome effluent.
Agro-textiles have been used in the agriculture sector for thousands of years and are an attractive tool for the protection of crops during their entire lifecycle. Currently, the agro-textile market ...is dominated by polyolefins or petrochemical-based agro-textiles. However, climate change and an increase in greenhouse gas emissions have raised concern about the future oil-based economy, and petroleum-based agro-textiles have become expensive and less desirable in the modern world. Other products include agro-textiles based on natural fibers which degrade so fast in the environment that their recovery from the field becomes difficult and unattractive even by efficient recycling or combustion, and their lifetime is usually limited to 1 or a maximum of 2 years. Hence, the development of bio-based agro-textiles with a reduced impact on the environment and with extended durability is foreseen to initiate the growth in the bio-based economy. The world is gradually preparing the shift toward a bio-based economy, and research for sustainable bio-based alternatives has already been initiated. This review provides insight into the various agro-textiles used currently in agriculture and the research going on in the area of agro-textiles to offer alternative solutions to the current agro-textile market.
Marine environments are largely unexplored and can be a source of new molecules for the treatment of many diseases such as malaria, cancer, tuberculosis, HIV etc. The Marine environment is one of the ...untapped bioresource of getting pharmacologically active nonribosomal peptides (NRPs). Bioprospecting of marine microbes have achieved many remarkable milestones in pharmaceutics. Till date, more than 50% of drugs which are in clinical use belong to the nonribosomal peptide or mixed polyketide-nonribosomal peptide families of natural products isolated from marine bacteria, cyanobacteria and fungi. In recent years large numbers of nonribosomal have been discovered from marine microbes using multi-disciplinary approaches. The present review covers the NRPs discovered from marine microbes and their pharmacological potential along with role of genomics, proteomics and bioinformatics in discovery and development of nonribosomal peptides drugs.
Tuning the structural architecture of the pristine two dimensional hexagonal boron nitride (h-BN) nanosheets through rational surface engineering have proven advantageous in the fabrication of ...competent catalytic materials. Inspired by the performance of h-BN based nanomaterials in expediting key organic transformations, we channelized our research efforts towards engineering the inherent surface properties of the exclusively stacked h-BN nanosheets through the incorporation of a novel competent copper complex of a bidentate chelating ligand 2-hydroxy-4-methoxybenzophenone (BP). Delightfully, this hybrid nanomaterial worked exceptionally well in boosting the 3 + 2 cycloaddition reaction of azide and nitriles, providing a facile access to a diverse variety of highly bioactive tetrazole motifs. A deep insight into the morphology of the covalently crafted h-BN signified the structural integrity of the exfoliated h-BN@OH nanosheets that exhibited lamellar like structures possessing smooth edges and flat surface. This interesting morphology could also be envisioned to augment the catalysis by allowing the desired surface area for the reactants and thus tailoring their activity. The work paves the way towards rational design of h-BN based nanomaterials and adjusting their catalytic potential by the use of suitable complexes for promoting sustainable catalysis, especially in view of the fact that till date only a very few h-BN nanosheets based catalysts have been devised.
Environmental stress induced genetic polymorphisms have been suggested to arbitrate functional modifications influencing adaptations in microbes. The relationship between the genetic processes and ...concomitant functional adaptation can now be investigated at a genomic scale with the help of next generation sequencing (NGS) technologies. Using a NGS approach we identified genetic variations putatively underlying chromium tolerance in a strain of Aspergillus flavus isolated from a tannery sludge. Correlation of nsSNPs in the candidate genes (n = 493) were investigated for their influence on protein structure and possible function. Whole genome sequencing of chromium tolerant A. flavus strain (TERIBR1) was done (Illumina HiSeq2000). The alignment of quality trimmed data of TERIBR1 with reference NRRL3357 (accession number EQ963472) strain was performed using Bowtie2 version 2.2.8. SNP with a minimum read depth of 5 and not in vicinity (10 bp) of INDEL were filtered. Candidate genes conferring chromium resistance were selected and SNPs were identified. Protein structure modeling and interpretation for protein-ligand (CrO
) docking for selected proteins harbouring non-synonymous substitutions were done using Phyre2 and PatchDock programs.
High rate of nsSNPs (approximately 11/kb) occurred in selected candidate genes for chromium tolerance. Of the 16 candidate genes selected for studying effect of nsSNPs on protein structure and protein-ligand interaction, four proteins belonging to the Major Facilitator Superfamily (MFS) and recG protein families showed significant interaction with chromium ion only in the chromium tolerant A. flavus strain TERIBR1.
Presence of nsSNPs and subsequent amino-acid alterations evidently influenced the 3D structures of the candidate proteins, which could have led to improved interaction with (CrO
) ion. Such structural modifications might have enhanced chromium efflux efficiency of A. flavus (TERIBR1) and thereby offered the adaptation benefits in counteracting chromate stress. Our findings are of fundamental importance to the field of heavy-metal bio-remediation.
Strategies to enhance the production of secondary metabolites, derived from medicinal and agriculturally important plants have been the subject of exploration to enable effective utilization of these ...biorepositories. Through symbiosis, arbuscular mycorrhizal fungi (AMF), modify plant primary and secondary metabolite biosynthesis. The relationship thus offers the opportunity to exploit combinations of host and fungus that maximize secondary metabolite production. We investigated different AMF host combinations for the enhancement of root-derived secondary metabolites from three plant species - ashwagandha (Withania somnifera (L.) Dunal), licorice (Glycyrrhiza glabra L.), and marigold (Tagetes erecta L.). Each host species was inoculated singly with each of five species of AMF, Glomus hoi, Claroideoglomus etunicatum, Claroideoglomus claroideum, Rhizophagus irregularis, and Acaulospora delicata and secondary metabolite production was assessed. Increased concentrations of the following secondary metabolites were found in roots after AMF establishment: for withaferin-A in ashwagandha (concentrations ranged from 11.5 to 43.5% above than in control non-mycorrhized roots depending on the host and AMF combination); in licorice, glycyrrhizic acid (1.51–3.92% above control) and glabridin (2.85–6.41% above control) and in marigold, alpha-terthienyl (1.51–7.18% above control). Specifically, among the AMF inoculations, the highest levels of secondary metabolite were found in ashwagandha and marigold inoculated with R. irregularis and for licorice following inoculation with C. etunicatum revealing the impact of different AMF species on different plant species. This underpinning knowledge of AMF symbioses with the plant host will augment the development of methods that will provide enhanced concentrations of secondary metabolites of commercial value.
•Inoculation of AMF improved secondary metabolite production in the host plants.•Ashwagandha and marigold showed maximum secondary metabolites production with Rhizophagus irregularis inoculation.•Licorice showed maximum secondary metabolites production with Claroideoglomus etunicatum inoculation.
Microalgal biomass has the ability to store huge amount of triacylglycerides as fatty ester methyl esters (FAME) and carotenoids which has made algae as potential candidate for biorefinery approach. ...Essential fatty acid such as palmitic acid, stearic acid, arachidonic acid and eicospentanoic acid have been produced which are known for their various applications. The present study was aimed to evaluate the influence of different light intensities (120 and 250 μE/m2/s) and photoperiod (16:8h and 13:11h light/dark cycle) on the production of lipid, biomass and lutein. Dunaliella tertiolecta and Nannochloropsis oculata was grown for 23 days in F/2, sea salt media (SSM, Distilled water (DW) and SSM (natural seawater media,NSW) under two different light intensities and photoperiod regimes at 25 ᵒC. SSM (NSW) showed maximum accumulation of lipid in D.tertiolecta (34.56 mg/L/d). SSM (DW)- biomass showed 1.5 times higher lutein productivity of 0.253 mg/L/d under 13:11h light/dark cycle at 250 μE/m2/s compared to same medium under 16:8h light/dark cycles at 120 μE/m2/s. Where as in N.oculata, F/2 biomass showed higher lipid and lutein productivity of 15.69 and 0.279 mg/L/d, respectively The laboratory scale cultivation parameters and related media cost showed the suitability of different culture media adaptation to large scale production.
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