Plant Nitrogen Metabolism: Balancing Resilience to Nutritional Stress andAbiotic Challenges

Plant growth and resilience to abiotic stresses,such as soil salinity and drought,depend intricately on nitrogen metabolism.This review explores nitrogen’s regulatory role in plant responses to these challenges,unveiling a dynamic interplay between nitrogen availability and abiotic stress.In the context of soil salinity,a nuanced rela-tionship emerges,featuring both antagonistic and synergistic interactions between salinity and nitrogen levels.Salinity-induced chlorophyll depletion in plants can be alleviated by optimal nitrogen supplementation;however,excessive nitrogen can exacerbate salinity stress.We delve into the complexities of this interaction and its agri-cultural implications.Nitrogen,a vital element within essential plant structures like chloroplasts,elicits diverse responses based on its availability.This review comprehensively examines manifestations of nitrogen deficiency and toxicity across various crop types,including cereals,vegetables,legumes,and fruits.Furthermore,we explore the broader consequences of nitrogen products,such as N_(2)O,NO_(2),and ammonia,on human health.Understand-ing the intricate relationship between nitrogen and salinity,especially chloride accumulation in nitrate-fed plants and sodium buildup in ammonium-fed plants,is pivotal for optimizing crop nitrogen management.However,prudent nitrogen use is essential,as overapplication can exacerbate nitrogen-related issues.Nitrogen Use Effi-ciency(NUE)is of paramount importance in addressing salinity challenges and enhancing sustainable crop productivity.Achieving this goal requires advancements in crop varieties with efficient nitrogen utilization,pre-cise timing and placement of nitrogen fertilizer application,and thoughtful nitrogen source selection to mitigate losses,particularly urea-based fertilizer volatilization.This review article delves into the multifaceted world of plant nitrogen metabolism and its pivotal role in enabling plant resilience to nutritional stress and abiotic challenges.It offers insights into future directions for sustainable agriculture.

Gene expression of 49 kDa apyrase,cytoskeletal proteins,ATPase,ADPase and amino acid contents of Pisum sativum(L.)cells germinated in Euryops arabicus(Steud.ex Jaub.&Spach)water extract

The present research reports of quick and marked changes induced by plant extract of Euryops arabicus in the gene expression of 49-kDa apyrases,cytoskeletal proteins,ATPases,ADPase and amount of amino acid of pea(Pisum sativum L.var.Alaska).Pellets of cytoskeletals proteins(27000 xg)were probed with anti-apyrase antibody,biotinylated anti-rat,actin and alpha and beta-tubulin for Western blotting.ATPase and ADPase activities were determined based on the hydrolytic efficacy of adenine triphosphate and adenine diphosphate.By 72 hours,the abundance of apyrases,cytoskeletal proteins and amount of amino acid in pellets of 27000 xg of germinated pea seeds in E.arabicus extracts were sharply increased than those sown in distilled water.All the samples exhibited that the stems had more amount from apyrases,cytoskeletal proteins,amino acids and ATPase and ADPase activities than primary leaves and primary roots that were germinated either on E.arabicus water extract or in distilled water.Based on the enzyme’s capability to hydrolyse nucleotide triphosphate and nucleotide diphosphate as well as the direct association between expression of 49-kDa apyrase and cytoskeletal proteins,E.arabicus water extract had an important effect on plant germinations.

Feasible design for electricity generation from Chlorella vulgaris using convenient photosynthetic conditions

Many recent studies are concerned with low cost,easy to handle and alternative renewable energy as a feasible solution for the upcoming crisis of energy shortage.Microalgae are unicellular entities the can only depend on CO_(2),water and solar power to cover their nutritional needs.The current study is concerned with using algal cells in a polymeric hydrogel,as a cheap source of energy for electricity generation.Chlorella vulgaris has been proved to be a promising algal species for electricity generation,as compared with Micractinium reisseri.PVA hydrogel has been used for the immobilization of both algal species in order to protect them from the adverse surrounding conditions in addition to its ability to slowly release the required water molecules according to needs.Under these conditions,C.vulgaris showed the ability to generate 60 mV compared with 15 mV generated by M.reisseri.Scanning electron micrographs showed nano-threads that bind the C.vulgaris cells to each other,indicating the ability of algae to create nanowires that facilitate the electron transfer among algal cells and from cells to the nearest electrode.However,we would expect an increase in the produced potential with simultaneous amendment of environmentally polluted water,such as sewage or waste water.Both of FTIR and raman spectroscopy proved the presence of the characteristic groups of PVA hydrogel and proved the proper integration of the algal cells inside the hydrogel cavities.

Isolation, purification and structure elucidation of three newbioactive secondary metabolites from Streptomyces lividans AM

Microorganisms are a huge mine of bioactive metabolites,and actinomycetes are one of the very active groups in this area.In this article,we are concerned about the full taxonomical characterization of Streptomyces lividans AM,isolated from Egyptian soil.This isolate produced three new bioactive metabolites,namely:1-Nona-decanoyl,4-oleyl disuccinate(1),filoboletic acid;(9Z,11E)-8,13-dihydroxy octadeca-9,11-dienoic acid(2),and sitosteryl-3β-D-glucoside(3).Extensive 1D and 2D NMR and HR-mass spectrometry were used to elucidate the structures of the three compounds.Moreover,ten known compounds were also identified.The antimicrobial activity of the producing organism and newly reported compounds(1–3)was investigated against a selected group of pathogenic microorganisms.A full taxonomical characterization of the strain was described as well.

Hydrothermal preparation of TiO_(2)-Ag nanoparticles and its antimicrobial performance against human pathogenic microbial cells in water

Water contaminated with pathogenic microbes is considered as one of the most common routes for transmitting diseases in human beings.Different methods have been applied for the decontamination of microbes in contaminated water.In the current study,an easy to do hydrothermal method has been used for the preparation of TiO_(2)-Ag nanoparticles.The obtained material was characterised using a scanning electron microscope(SEM)and fourier transform infra-red spectroscopy(FTIR).The morphological appearance of the obtained nanoparticles was in the shape of a sphere with a size range of 60-90 nm.The antimicrobial activity of the prepared nanoparticles was tested against several pathogenic bacteria and fungi.The obtained results proved that the nanoparticles succeeded to affect all the tested microbes in the following order:Bacillus cereus ATCC6633>Pseudomonas aeruginosa ATCC9027=Klebsiella pneumoniae ATCC13883>Vibrio cholera ATCC700=Candida albicans ATCC 700=Escherichia coli NCTC10418>Staphylococcus aureus ATCC6538.The minimum inhibitory concentration(MIC)of the prepared nanoparticles varied among the tested microbes at range of 12 mg/ml and 25 mg/ml.These results encourage the application of prepared TiO_(2)-Ag nanoparticles for treatment of microbe-contaminated waters.

Fungal assembly of L-asparaginase using solid-state fermentation:a review

Because of its antitumor therapeutic-activity,as well as its application in food industries to improve the quality,L-asparaginase has attracted considerable attention from several investigators.In recent years,fungi have occupied advanced rank among microorganisms in the production process of the enzyme.This review is spotting the light on the advantages of fungal enzyme and its applications in the food industry and medications.The solid-state fermentation was discussed as the wide alternative and most accepted biosynthesis technique.However,some lights were also spotted to the statistical experimental design of the fermentation process,mainly on the methodology of the response surface for L-asparaginase biosynthesis by fungi.Finally,the immobilization of the enzyme and the features of the widely used solid substrates for the maximization of the production process were explored.

Biosynthesis of raw starch degradingβ-cyclodextrin glycosyltransferase by immobilized cells of Bacillus licheniformis using potato wastewater

The study was sought to enhance the synthesis of thermal stableβ-cyclodextrin glycosyltransferase(β-CGTase)using potato wastewater as a low-cost medium and assess the degree to which it is efficient for industrial production ofβ-cyclodextrin(β-CD)from raw potato starch.Thermophilic bacteria producingβ-CGTase was isolated from Saudi Arabia and the promising strain was identified as Bacillus licheniformis using phylogenetic analysis of the 16S rRNA gene.Alginate-encapsulated cultures exhibited twice-fold ofβ-CGTase production more than free cells.Scanning electron microscopy(SEM)of polymeric capsules indicated the potential for a longer shelf-life,which promotes the restoration of activity in bacterial cells across semi-continuous fermentation ofβ-CGTase production for 252 h.The optimal conditions forβ-CGTase synthesis using potato wastewater medium were at 36 h,pH of 8.0,and 50°C with 0.4%potato starch and 0.6%yeast extract as carbon and nitrogen sources,respectively.The purified enzyme showed a specific activity of 63.90 U/mg with a molecular weight of∼84.6 kDa as determined by SDS-PAGE analysis.The high enzyme activity was observed up to 60°C,and complete stability was achieved at 75°C.High levels of activity and stability were shown at pH 8.0,and the pH range from 7.0–10.0,respectively.The enzyme has an appreciable affinity for raw potato starch with a Km of 5.7×10−6 M and a Vmax of 87.71μmoL/mL/min.β-CD production was effective against 25 U/g of raw potato starch.The outcomes demonstrated its feasibility to develop a fermentation process by integrating the cost-effective production ofβ-CGTase having distinctive properties forβ-CD production with ecofriendly utilization of potato wastewater.

Antimicrobial activities of three seaweeds extract against some human viral and bacterial pathogens

Microbial infections cause complicated health influences along with bad economic impacts.In the present investigation,three dominant seaweeds namely,Amphiroa anceps,Corallina officinalis and Sargassum filipendula were collected from different Egyptian sites at the Red Sea and Mediterranean Sea during autumn 2019.Organic extracts of the three algae were screened for their antibacterial activity against three pathogenic bacteria Salmonella typhiimurium,Staphylococcus aureus and Escherichia coli,in addition to in vitro antiviral activity against Rotavirus(RV),and Coxsackie virus B3(CVB3)that cause severe diseases in human.Organic extract of A.anceps,C.officinalis and S.filipendula inhibit E.coli cells by 57.1%,85.7%,and 91.4%,respectively.The highest level of concentration of the C.officinalis extract(100μg/mL)inhibits 100%of Staphylococcus aureus cells followed by S.filipendula and A.anceps extract which inhibit 82.5%and 75%of S.aureus.Similarly,the highest concentration of C.officinalis extract inhibits S.typhiimurium by 80%.The extract of A.anceps exhibited a high antiviral effect against RV infection with TI=22 and virus titers lessened by 2.75 log TCID_(50) followed by extractions of C.officinalis with TI=18.3 and virus titers reduced by 2.5 log TCID_(50).Against CVB3 infection,the extract of A.anceps causes the highest antiviral activity with TI=15 and reduce the viral titers by 2.5 log TCID_(50),followed by extractions of C.officinalis with TI=8.8 and inhibition of virus titers by 1.75 log TCID_(50).Extract of S.filipendula displayed the lowest antiviral effects against RV and CVB3 infection with TI=2.4 and 1.4,respectively.The obtained results clarified that the extract of three marine seaweeds maintains a potent antimicrobial activity,making them a future promising source of new antimicrobial drugs.

Secondary antiviral metabolites from fungi with special reference to coronaviruses

Profound inspection of the life forms on the earth teaches how to be the complexity of interrelationships among the various systems.Because of the emergence of novel viruses all the time and the inadequate of vaccines and antivirals,viral contagions are amongst the most causative diseases affecting people worldwide.Fungi exemplify a massive source of bioactive molecules as,many fungal secondary metabolities like Oxoglyantrypine,Carneic acid F,Scedapin C,Asteltoxin E,Phomanolide,Norquinadoline A and Quinadoline B have antiviral activity.This review deals with how secondary metabolites of fungi can help in the war against viruses in general and especially Coronaviruses moreover several pieces of literature pointed out that many clusters of fungi in different biotopes are waiting to be exploited.

Cloning and characterization of 66 kDa streptavidin-binding peptides(SBP)of Pisum sativum L.embryo specific to var.Alaska

The aim of the current research was to clone and to characterize the partial 66 kDa streptavidin-binding peptide(SBP)found in the germinated embryos of Pisum sativum L.var.Alaska.The pea(P.sativum var.Alaska)embryos possess prominent 66 kDa SBPs that gradually disappeared after few hours of germination in germinated embryos,but not in the cotyledons.The total RNA was isolated from embryos of P.sativum but could not be isolated from the cotyledons.The partial nucleotides sequences of 66 kDa SBPs of embryonic stalk(P.sativum var.Alaska)were cloned and identified using pMOSBlue vector.66 kDa(SBP)gene from the embryos of P.sativum var.Alaska possesses 327 bp having an open reading frame(ORF)region in a part of the gene that encoded for 108 amino acids.Alignment showed similarity among 66 kDa SBPs P.sativum var.Alaska,with P.sativum seed biotinylated protein(SBP65)and P.sativum sbp65a mRNA with DNA distance matrix between 0.0094 to 1.2676.MALDI-TOF mass spectrometry analysis of 66 kDa(SBP)proteins showed it had similar short peptides to 19 proteins found in different organisms,especially Convicilin precursor,and the seed biotinylated protein in P.sativum.The alignment results of both nucleotide sequences and amino acid residues either from cloning or MALDI-TOF-MS showed differences with related species,especially P.sativum.No mRNA was found in the cotyledons during seeds germination,which means no metabolic activities and this part may act only as food reservoirs for growing newly embryos.

Nanoparticles induce the biosynthesis and activity of the new possible therapeutic proteinase source,Talaromyces purpureogenus KJ584844

The need for the bacterial proteinase is rapidly growing,urging to catch a lowcost medium for the microbial fermentation,nanoparticles can play a vital role in this respect.The proteinase of Talaromyces purpureogenus was produced on the tubers of Helianthus tuberosus that also operated as solid support for the fermentation process.The interface amongst nitrogen sources(NH_(4)Cl and yeast extract)was investigated,applying the statistical modeling of central composite design under solid-state fermentation.The optimum medium for proteinase secretion was stimulated by 979.82 mg NH_(4)Cl and 437.68 mg yeast extract per 100 g substrate,yielding 108.15 U/g tubers.Using Plackett-Burman experimental design,the nanoparticles Co,Ni and Fe were assessed as inducers for proteinase stimulants.Co nanoparticles(5 ppm)were the greatest in both proteinase production by the fungus as well as an inducer of the proteolysis process by the enzyme when using faba bean straw as a proteinaceous substrate in the reaction mixture,liberating the extreme quantity of amino acids,compared with the lack of the nanoparticles.The findings suggest the incorporation of Co nanoparticles in both the proteinase fabrication process and during the degradation of proteinaceous materials induce proteinase catalyst.This approach could be extended to modulate the productivity and activity of similar biomolecules.

Potential detoxification of aflatoxin B2 using Kluyveromyces lactis and Saccharomyces cerevisiae integrated nanofibers

Current investigation has shown that human exposure to aflatoxins is not limited to the administration of contaminated cereals,but water is another possible source.This study was aimed to design easily applicable method to eliminate aflatoxin B2(AFB2)from contaminated drinking water.Electrospinning has been used for preparation of probiotic-coated polyvinyl alcohol(PVA)and cellulose acetate(CA)nanofibers.Both of these hybrid nanofibers were studied by scanning electron microscopy(SEM)and Fourier-transformed infrared spectroscopy(FT-IR).SEM showed the proper coating of probiotic strains(Kluyveromyces lactis CBS 2359 and Saccharomyces cerevisiae ATCC 9763)on both nanofiber types.Different areas(1-5 cm^(2))of the probiotic-nanofiber hybrid were used to enhance the removal of 20 ng/ml of aflatoxin B2(AFB2)from prepared AFB2-contaminated water over time.Results revealed that a 5 cm^(2) area of probiotic-coated PVA nanofibers can eliminate 97.5% of AFB2 as compared to 87.5%,90.5%,93.5%,and 95.5%,for 1 cm2,2 cm^(2),3 cm^(2),and 4 cm^(2),respectively,while probiotic-coated CA nanofibers were slightly less effective.Nevertheless,the cytotoxicity of probiotics-CA treated water on cultured human fibroblasts was almost 10 times lower than the cytotoxicity recorded in probiotics-PVA treated water.Therefore,results of the current research suggest that probiotics-polymer nanofiber membranes can be used as an extra stage in the water purification system for the treatment of AFB2-contaminated water.