Showing papers in "Biocatalysis and agricultural biotechnology in 2020"
TL;DR: Using microbes as bioinoculants is believed to be the best substitute of chemical fertilizers as eco-friendly manner for plant growth and soil fertility.
Abstract: Biofertilizers consists of the microorganisms bringing about the improvement of the nutrients of the soil enhancing their accessibility to the crops. Plant nutrients form the most vital components of the sustainable agriculture. Producing healthy crops for the fulfillment of the demands of the world's growing population is completely dependent upon kind of the fertilizers being used to provide the plants with all the major nutrients but more dependability on the chemical fertilizers is destroying the environmental ecology and negatively influencing the health of humans. Thus, using microbes as bioinoculants is believed to be the best substitute of chemical fertilizers as eco-friendly manner for plant growth and soil fertility. These microbes are known to be the potent tool to provide substantial benefits to crops for sustainable agriculture. The beneficial microbes colonize the plant (epiphytic, endophytic and rhizospheric) systems of crops and plays significant role in nutrient uptake from surrounding ecosystems of plants. The plant associates microbes have ability to promote growth of plant under the natural as well as extreme conditions. These plant growth promoting microbes enhance the plant growth by various direct and indirect plant growth promoting mechanisms such as biological nitrogen fixation, the production of various plant growth hormones, siderophores, HCN, various hydrolytic enzymes and solubilization of potassium, zinc, and phosphorus. Extensive work on the biofertilizers has been done and even available which clearly reveals that these microbes possess the potential of providing the vital nutrients to the crops in adequate quantities for the enrichment of yield of the crops without disturbing the environment.
253 citations
TL;DR: The simplified model summarises the green synthesis, its characterization using physicochemical means and their biomedical applications, and discusses the recent advances in green synthesis of metallic nanoparticles, milestones, therapeutic applications and future perspectives of biosynthesized nanoparticles from some important medicinal plants.
Abstract: The cornerstone of nanoscience and nanotechnology are nanoparticles which have immense power and functional ability in diverse fields. Nanoparticles are synthesized by physical, chemical methos but limitations are due to its toxicity. We have discussed few green synthesis routes which are eco friendly and less toxic methods, including alage, microorganisms, plants etc.. Expoiting the potential of medicinal plants, is one of the green synthesis routes and is significant because the current therapeutic approaches have toxicity problems and microbial multidrug resistance issues. As the metal nanoparticles have received great attention across the globe, so in this study we have discussed and focused many different metallic nanoparticles obtained by green synthesis using medicinal plants. We have also discussed the types, size and medicinal properties like antibacterial, antifungal, anticancer, antiviral activities of nanoparticles. The biomolecules, secondary metabolites and coenzymes present in the plants help in easy reduction of metal ions to nanoparticles. Such nanoparticles are considered as potential antioxidants and promising candidates in cancer treatment. The simplified model summarises the green synthesis, its characterization using physicochemical means and their biomedical applications. Succinctly, we have discussed the recent advances in green synthesis of metallic nanoparticles, milestones, therapeutic applications and future perspectives of biosynthesized nanoparticles from some important medicinal plants.
123 citations
TL;DR: Drought-adaptive phosphorus-solubilizing microbes in rhizospheric soil of different cereals and pseudocereals and their role in mitigation of drought stress in great millet is investigated.
Abstract: Among the extreme habitats, drought is most harsh abiotic stress affecting growth, development and productivity of crops. Plants also face limitations of certain nutrients such as phosphorus required for different physiological and metabolic activities. Stress-adaptive phosphorus-solubilizing microbes in rhizospheric soil can help plants to combat water scarcity and overcome the problem of phosphorus unavailability to plant systems. The present investigation deals with the isolation of drought stress adaptive and P-solubilizing microbes from rhizospheric soil of different cereals and pseudocereals and their role in mitigation of drought stress in great millet. A total of 193 rhizospheric microbes were isolated and screened for their capability to solubilize phosphorus under drought stress. Twenty isolates exhibited P-solubilizing attribute under drought stress, which were further screened for plant growth promoting (PGP) traits such as solubilization of zinc and potassium; production of Fe-chelating compounds, indole acetic acid, hydrogen cyanide and ammonia. On basis of multifunctional PGP traits, two efficient and potential microbes were evaluated for PGP in great millet in vitro under green house with different water regimes. The isolates were found to be efficient in terms of enhancing accumulation of different osmolytes such as glycine betaine, proline, sugars, increased chlorophyll content, and decreasing lipid peroxidation. The isolates were identified by 16S/18S rRNA gene sequencing as Streptomyces laurentii EU-LWT3-69 and Penicillium sp. strain EU-DSF-10. To best of our knowledge Streptomyces laurentii has been reported first time as PGP and drought adaptive bacterium. PGP drought-adaptive phosphorus solubilizers could be used as bioinoculants for crops under water scarcity ecosystems.
113 citations
TL;DR: This review infers that subsidizing supported research and a move of microalgal research objective from biofuels generation to bio-refinery co-items can ensure them as valuable resource.
Abstract: Microalgae offer fascinating highlights to be enable them as elective raw material for different applications through bio-refining process. They have special capacities to use them for biotechnology oriented applications. In this way, this review examines to grow the extent of incorporating microalgae along with different other biorefinery applications to upgrade their maintainability. The utilization of microalgae as animal and fish feed, manures, pharmaceutical, cosmeceutical, environmental and other biotechnological applications are altogether assessed. It additionally features the boundaries, openings, improvements, what's more, probabilities of expanding the extent of microalgae through techno-economic analysis. This review infers that subsidizing supported research and a move of microalgal research objective from biofuels generation to bio-refinery co-items can ensure them as valuable resource. In addition, innovation joining is inescapable to bypass the expense of biomass handling of microalgae. It is anticipated that this review would be useful to decide the future job of microalgae in bio-refinery applications.
102 citations
TL;DR: In this article, the stabilization and the bio-reduction of silver nanoparticles were described by adopting UV-vis spectrometry interprets the surface plasmon resonance peak at 449nm.
Abstract: Biological synthesis of metal nanoparticles is one of the effortless, cost - effective, environmental - friendly methods and scale down the handling of toxic chemicals. The silver nanoparticles were triumphantly synthesized from the silver nitrate solution through a greener route using Indian gooseberry (phyllanthus emblica) fruit extract and the prepared particles are of well-balanced shape and size. The stabilization and the bio-reduction of silver nanoparticles were described by adopting UV–vis spectrometry interprets the surface plasmon resonance peak at 449 nm. The functional groups of phyllanthus emblica fruit extract and the silver nanoparticles were diagnosed by using Fourier transform Infrared spectrum (FTIR). The crystalline nature of face-centered cubic (FCC) was examined by X-ray diffraction (XRD) and the crystalline size ranges between 19 nm to 45 nm with an average size 30 nm. Scanning electron microscope (SEM) witnessed the hexagonal shape of silver nanoparticles and Energy-dispersive X-ray spectroscope (EDX) assured the well-established fabrication of nanocrystalline silver element. The synthesized nanoparticle exhibits significant antibacterial effects and very clear zone of inhibition against Klebsiella pneumoniae and Staphylococcus aureus bacterias.
98 citations
TL;DR: This review will emphasize the role of biosynthesized AgNPs for its antimicrobial application which will provide further insight towards better health, environment and prevention from infectious diseases.
Abstract: Silver is a potent antimicrobial agent which is used in the form of nanomaterial or as metal salts for antimicrobial applications. Antimicrobial agents have a major role in water treatment, chemical industries, food preservation, aquaculture ponds, agricultural productivity and biomedical applications. Presently, due to emergence of nanoscience and technology metallic silver nanoparticles (AgNPs) are used as antimicrobial agent and is synthesized by following various protocols. In this review article, plants and algae mediated AgNPs synthesis is highlighted and their application as an antimicrobial agent is discussed. This review will emphasize the role of biosynthesized AgNPs for its antimicrobial application which will provide further insight towards better health, environment and prevention from infectious diseases.
88 citations
TL;DR: In this paper, methanolic and water extracts of pennyroyal (Mentha pulegium) were evaluated for their antioxidant profiles by eight distinguished bioanalytical methods and for their inhibitory effects against enzymes linked to different diseases.
Abstract: Methanol and water extracts of pennyroyal (Mentha pulegium) were evaluated for their antioxidant profiles by eight distinguished bioanalytical methods and for their inhibitory effects against enzymes linked to different diseases, namely acetylcholinesterase, butyrylcholinesterase, α-glycosidase and α-amylase. Additionally, the antioxidant properties of both extracts were determined and their polyphenolic compositions were evaluated by LC-MS/MS. For estimation of the antioxidant capacities of methanolic extract of pennyroyal (MEP) and water extract of pennyroyal (WEP); 2,2′-azino-bis-3-ethylbenzthiazoline-6-sulphonic acid radical (ABTS•+), 1,1-diphenyl-2-picrylhydrazyl free radical (DPPH•), and N,N-dimethyl-p-phenylenediamine (DMPD•+) scavenging activities, Fe3+-2,4,6-tris(2-pyridyl)-s-triazine (TPTZ), Fe3+, and Cu2+ reducing assays were studied. The IC50 values of the MEP and WEP indicated that they were potent effective DPPH· (16.92 and 18.52 μg/mL), ABTS•+ (7.92 and 9.37 μg/mL) and DMPD•+ (36.02 and 38.94 μg/mL) scavengers, as well as acetylcholinesterase (AChE) (40.76 and 60 μg/mL), butyrylcholinesterase (BChE) (49.51 and 63.03 μg/mL), α-glycosidase (20.38 and 21.65 μg/mL) and α-amylase (23.11 and 36.47 μg/mL) inhibitors. Plant materials are potential sources for novel products in food and pharmaceutical applications. Also, biologically active compounds from plants have proven to be desirable in cosmetics, foods, and pharmaceuticals. This study clearly showed that both MEP and WEP had a broad screening of active compounds and phytochemicals. As a result of this abundant active ingredient, both extracts possessed antioxidant, anticholinergic and anti-diabetes properties.
76 citations
TL;DR: In this paper, callus extract of Cinnamonum camphora was utilized to the synthesis of silver nanoparticles (Ag-NPs) for the first time Callus culture was propagated in murashige and skoog (MS) medium, and sub-cultured for 3 successive times with 4 week intervals.
Abstract: Plant tissue culture is considered as a basic and fundamental component of plant biotechnology and is considered a good approach for green synthesis of nanoparticles (NPs) because it is safe, eco-friendly and clean method In the current study, callus extract of Cinnamonum camphora was utilized to the synthesis of silver nanoparticles (Ag-NPs) for the first time Callus culture of C camphora was propagated in murashige and skoog (MS) medium, and sub-cultured for 3 successive times with 4 week intervals The propagated callus cultures are incubate at different five light conditions using 1500 Lux, white, green, yellow, red and full dark condition After that, calli which showed the best callus dry biomass was utilized to synthesis Ag-NPs through formation of callus extract Green synthesized Ag-NPs was characterized by UV–Vis spectroscopy, TEM, SEM-EDX, DLS, FT-IR, and XRD Results affirmed the ability of callus extract of C camphora to fabricate spherical Ag-NPs with average size 547–948 nm at wavelength 420 nm Also, the crystallographic structure of nanoparticle are confirmed by XRD analysis Silver ion was represented by 573% of the total weight elements in NPs solutions as showed by EDX analysis In addition, Ag-NPs exhibited broad spectrum activities against Staphylococcus aureus, Bacillus subtilis, Escherichia coli and Pseudomonas aeruginosa with inhibition zones 196 ± 08, 19 ± 05, 171 ± 07 and 151 ± 04 mm respectively
76 citations
TL;DR: In this article, the authors investigated the effects of medium-inoculated rhizobacteria (PGPRs) on wheat growth and productivity under two NaCl-salinity levels (150 and 300mM).
Abstract: Plant growth-promoting rhizobacteria (PGPRs) can suppress salt stress effects and improve plant productivity. This study elucidated the mechanisms of growth medium-inoculated PGPRs (Bacillus cereus, Serratia marcescens, and Pseudomonas aeruginosa), which contribute to improving salinity tolerance in Triticum aestivum plants grown under two NaCl-salinity levels (150 and 300 mM). The objective was to assess the impacts of soil-inoculated PGPRs on physiological attributes, antioxidant system activities, and their implications for growth and productivity of wheat plants in a pot study. Salinity levels markedly decreased growth and output traits, photosynthetic pigments, gas exchange, membrane stability, plant water content, K+ and Ca2+ contents, and K+/Na+ ratio. While, proline and soluble sugars contents, Na+ and oxidative stress biomarkers (e.g., O2•− and H2O2), and antioxidant activities were increased by salinity compared to control. The adverse effects were more pronounced with 300 mM NaCl. However, PGPRs detoxified salinity stress effects and significantly improved all physiological attributes and further elevated antioxidant activities, while significantly reduced levels of Na+ and oxidative stress biomarkers, which were reflected in significant elevations in plant growth and production. These improvements using PGPRs were better under 150 mM NaCl. The growth-enhancing traits of these halo-tolerant PGPRs like indole-3-acetic acid (IAA) and hydrogen cyanide (HCN) productions, N2-fixation, and P solubilization, reported in this investigation not only helped wheat plants withstand salt stress but also facilitated their growth under varying concentrations of salts. Thus, the use of PGPRs can be an effective strategy to boost wheat growth and production in salt-affected areas.
62 citations
TL;DR: Significant research on the bacterial sources, production conditions, enzyme characteristics, mechanism and structure, industrial applications as well as role of cutting edge “multi omics” and “synthetic biology” techniques for improved lignin degradation have been discussed.
Abstract: Lignin is the second abundant biomass (10–35%) which is associated with cellulose and hemicellulose in plant cellwall. It has complex aromatic structure and high molecular weight which makes it resistant as well as difficult to degrade by microorganisms. Although, white-rot fungi has high capability of lignin depolymerization by producing array of enzymes; but they are not applicable in actual industrial conditions. In comparison to fungi, bacteria can tolerate wider pH, temperature, oxygen ranges and are easy to genetically manipulate. The bacterial ligninolytic enzymes can be divided in following major category: lignin modifying enzymes (LME) i.e. lignin peroxidase, manganese peroxidase, dye decolorizing peroxidase, laccase (phenol oxidase) and lignin-degrading auxillary enzymes (LDA) i.e. β-aryl ether, biphenyl, phenyl coumarane, ferulate degrading enzymes, superoxide dismutase, catalase peroxidase. LDA enzymes assist core lignin degrading enzymes and degrade a dimer or monomer after depolymerization of lignin macromolecule. These enzymes have broad applications in bioremediation of textile, pulp industry waste water, aromatic compounds and in production of bioplastic etc. Therefore, this review article summarize significant research on the bacterial sources, production conditions, enzyme characteristics, mechanism and structure, industrial applications as well as role of cutting edge “multi omics” and “synthetic biology” techniques for improved lignin degradation have also been discussed.
59 citations
TL;DR: In this paper, a comprehensive review of the cold flow properties of biodiesel is presented, which covers relevant topics such as (a) biodiesel compositions, (b) cold flow conditions (e.g., pour point, cloud point, cold filter plugging point), (c) mechanisms, factors affecting and impact of cold flow, (d) oxidative stability, (e) methods to improve the cold-flow properties, (f) method to improve biodiesel oxidative stability and et cetera.
Abstract: Poor cold flow properties of biodiesel especially those that are composed mainly of saturated fatty acids is one of the major drawbacks faced by most biodiesel manufacturers. During winter or cold weather, the biodiesel tend to solidify which clogs fuel lines, filters and injectors that lead to engine operability problems. As it limits biodiesel marketability, it is desirable to improve these properties. Literatures have shown that there are numerous ways that can be used. However, lack of review papers in this area especially on the fundamentals aspects of biodiesel properties makes it difficult to choose the best and suitable improvement method that is compatible with the biodiesel type itself. This paper therefore aims to provide a comprehensive review on this area which covers relevant topics such as (a) biodiesel compositions, (b) cold flow properties (e.g. pour point, cloud point, cold filter plugging point), (c) mechanisms, factors affecting and impact of the cold flow properties, (d) oxidative stability, (e) methods to improve the cold flow properties, (f) methods to improve biodiesel oxidative stability and et cetera. This information is hoped to give deeper understanding on the fundamentals and new perspectives towards the production line to produce desirable quality of biodiesel that is marketable around the globe.
TL;DR: In this paper, a watery mixture of pomegranate (Punica granatum L.) seed extract and AgNO3 solution was used to synthesize starch nanoparticles (StNPs) in an aqueous sulfuric acid solution (3.2M) as an abundant, inexpensive and biodegradable polysaccharide.
Abstract: Packaging is one of the most important issues regarding food safety. Nanoscale technology can be used to improve the quality of packaging components, thereby ensuring food safety. The poor biodegradability and the environmental impact of discarded plastics have prompted scientists to develop newer plastic makes with higher environmental degradability, particularly in the field of food packaging. The mechanical properties of the newly prepared nanocomposites films are of prime importance the packaging applications. These films can be evaluated for the tensile strength and modulus of elasticity, yield strength, ultimate tensile strength, and toughness. In a watery mixture of pomegranate (Punica granatum L.) seed extract and AgNO3 solution, silver nanoparticles (AgNPs) were biosynthesized. Starch was used to synthesize starch nanoparticles (StNPs) in an aqueous sulfuric acid solution (3.2 M) as an abundant, inexpensive and biodegradable polysaccharide. The characterization of nanoparticles was based on FTIR, UV spectroscopy, FESEM, X-ray diffraction, and EDS. The AgNPs and StNPs had particle sizes of 19–54 nm and 43–191 nm, respectively, under the microscope. In thermoplastic maize starch films, AgNPs and StNPs were then used as reinforcements to improve the mechanical properties of the films. After nanoparticles were incorporated, the tensile strength and extensible properties of the films were increased. Incorporation of StNPs and AgNPs into maize starch films provided nanocomposites with suitable mechanical properties. The results of this study have been shown to increase their mechanical properties and physical resistance by simultaneously adding nanocomposites with specific ratios to films.
TL;DR: Oleogels have been recognized as very promising alternatives to trans and saturated fats although none of them are yet used on a commercial basis as mentioned in this paper, which is because oleogel technology is relatively new to the food industry.
Abstract: Oleogels developed for foods are typically composed of a vegetable oil and a food-grade oleogelator or a combination of multiple oleogelators. During the last decade, the interest in the oleogel technology has dramatically increased due to the concern of the negative health effects of trans and saturated fats used in foods. Oleogels have been recognized as very promising alternatives to trans and saturated fats although none of them are yet used on a commercial basis. This is because oleogel technology is relatively new to the food industry. Fundamental studies have been conducted to understand gelation phenomena, crystal structures of oleogelators and networks of crystals that affect physical properties of oleogels. Recently, studies on their practical application in foods have also been conducted. Oleogels were incorporated in real foods such as cakes, muffins, biscuits, sausages, burgers, instant fried noodles, peanut butters, and many other food products. Furthermore, efforts have been made to enhance the gelation ability of an oleogelator by adding another oleogelator or an additive. It has been recognized that sensory properties and oxidative stability of oleogel-containing foods are critical to the practical application of the oleogel technology in foods. These properties have been evaluated for spreads, margarine, cookies, sausages, meat patties, and meat batters. Although some studies found that oleogels had positive or negligible negative effects on sensory and oxidation properties, some studies found that further studies were needed to achieve satisfactory sensory properties and oxidative stability of oleogel-containing food products.
TL;DR: In this article, ZnO NPs were synthesized using Melia azedarach leaf extract with zinc nitrate as initiating material and X-Ray Diffraction (XRD) spectrum confirmed that the synthesized zinc oxide particles were in the form of nanocrystals.
Abstract: Zinc oxide nanoparticles (ZnO NPs) were synthesized using Melia azedarach leaf extract with zinc nitrate as initiating material. Synthesized nanoparticles shows the Ultra Violet – Visible (UV–Vis) Spectroscopy absorption peak at 372 nm which is one of the distinct features of ZnO NPs. Fourier Transform Infrared (FTIR) Spectrum implies that the role of aliphatic amines, alkyl halides and carboxylic acids were responsible for the synthesis of ZnO NPs and its stability. X- Ray Diffraction (XRD) spectrum confirmed that the synthesized zinc oxide particles were in the form of nanocrystals. Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM) images showed hexagonal and spherical shapes of synthesized zinc oxide nanoparticles size ranges between 33 – 96 nm. The Energy Dispersive X-Ray Analysis (EDAX) confirmed that the presence of zinc content in the synthesized zinc oxide nanoparticles and it asserts that the process of biosynthesis of nanoparticles was carried out in accordance. The overall antioxidant studies revealed significant scavenging activities ranges from minimum 10.63% to maximum 54.97%. Biosynthesized ZnO NPs having efficient biological activities regarding anti-oxidant and antibacterial potential which might be utilized in several biological applications.
TL;DR: In this article, the methanol extract of Stachys annua (MESA) and the water extract (WESA) were prepared and used for all biochemical analyses, and the results showed high inhibition effects against α-amylase and α-glycosidase enzymes, whereas they showed low inhibition effect against AChE and BChE enzymes.
Abstract: Some biochemical properties including phenolic content, anticholinergic, antidiabetic, and antioxidant activities of Stachys annua were determined in this study. The methanol extract of Stachys annua (MESA) and the water extract of Stachys annua (WESA) were prepared and used for all biochemical analyses. Antioxidant capacities of MESA and WESA were evaluated by six different in vitro bioanalytical methods including three reducing antioxidant methods and three radical scavenging antioxidant methods. Also, enzyme inhibition effect of Stachys annua against acetylcholinesterase (AChE), butyrylcholinesterase (BChE), α-amylase, and α-glycosidase enzymes were determined separately. According to the results, both extracts showed high inhibition effects against α-amylase and α-glycosidase enzymes, whereas they showed low inhibition effects against AChE and BChE enzymes. The IC50 values of MESA and WESA against AChE (119.8 ± 2.4 μg/mL and 150.1 ± 3.0 μg/mL), BChE (192.1 ± 3.8 μg/mL and 186.7 ± 3.7 μg/mL), α-glycosidase (25.7 ± 0.5 μg/mL and 18.7 ± 0.4 μg/mL), and α-amylase (43.3 ± 0.9 μg/mL and 11.4 ± 0.2 μg/mL) were determined, respectively. Another goal of the study was to evaluate the phenolic compositions of Stachys annua by liquid chromatography and tandem mass spectrometry (LC-MS/MS). Quercetagetin-3,6-dimethylether (178.6 ± 33.5 μg/g), chlorogenic acid (118.2 ± 16.4 μg/g), and fumaric acid (102.5 ± 7.1 μg/g) were identified as major compounds in MESA. On the other hand, fumaric acid (309.5 ± 21.5 μg/g), apigenin (144.6 ± 11.7 μg/g), and chlorogenic acid (78.1 ± 10.8 μg/g) were identified as major compounds in WESA. This study will be a scientific base for further studies about Stachys annua for food or medicinal utilization.
TL;DR: In this paper, the authors used poly-e-caprolactone nanoparticles entrapped with palmarosa essential oil and geraniol, the majoritarian compound of the essential oil.
Abstract: Palmarosa (Cymbopogon martinii) essential oil is a rich source of geraniol monoterpene, with antimicrobial and antioxidant properties. However, bioactive compounds present chemical instability under adverse temperature conditions due to their high volatility characteristics. Therefore, the aim of this work was to produce poly-e-caprolactone nanoparticles entrapped with palmarosa essential oil and geraniol, the majoritarian compound of palmarosa essential oil. Entrapped nanoparticles were characterized by particle size, polydispersity index, zeta potential, morphology, encapsulation efficiency, differential scanning calorimetry (DSC), antioxidant capacity and antimicrobial activity. The average sizes of the loaded nanoparticles was 282.1 ± 0.4 nm and 289.3 ± 1.5 nm, for geraniol and palmarosa oil respectively, and 207.8 ± 0.1 nm for the free loaded nanoparticles. The polydispersity results were lower than 0.140, indicating a unimodal distribution. All formulations showed zeta potential lower than 30 mV, indicating a good stability. High values of encapsulation efficiency were obtained, explained by the hydrophobicity of the essential oil and geraniol. Evaluating the morphology, nanoparticles presented a spherical shape, with a capsular structure. The encapsulation was confirmed by DSC, by changes in onset and endset temperatures, when the nanoparticles were compared to the pure compounds. Nanoparticles presented antioxidant activity against DPPH free radical and positive inhibition results against Staphylococcus aureus and Escherichia coli. Based on the results obtained, poly-e-caprolactone nanocapsules presented good physicochemical characteristics, suggesting applicability in perfumery, cosmetics, and in the pharmaceutical industries.
TL;DR: The role of salicylic acid on photosynthetic electron transfer chain of mung-bean plants grown under salt stress (0, 3, 6 and 9 dS/m2) was studied using chlorophyll a fluorescence (ChlF) measurements.
Abstract: The role of salicylic acid (0, 1 and 1.5 mM) on photosynthetic electron transfer chain of mung-bean plants grown under salt stress (0, 3, 6 and 9 dS/m2) was studied using chlorophyll a fluorescence (ChlF) measurements. Results indicated that accumulation of K+ content decreased but, Na+ content increased with increasing salt stress. SA-treated plants had more K+ and less Na+ content compared with the non-SA treated plants. Application of SA, especially with 1 mM, increased the I–P step of the OJIP transient curve of fluorescence. Salt stress decreased gs, CCI, FV, FM, SM and PIabs in plants. However, the time taken to reach FM (TFM) increased with increasing salt stress. Application of different concentrations of SA significantly improved gs, CCI, FV, SM, and PIabs of plants. Photosynthetic efficiency of plants improved as a result of SA application via decreasing Fo and increasing FV/FM, FV/Fo, SM/TFM and Area under both saline and non-saline conditions. Accumulation of Na+ had negative, but K+ had a positive correlation with gs, CCI and most of the chlorophyll a fluorescence parameters (except, Fo and TFM). A positive correlation was found between gS and CCI with PIabs. This research indicated that low gs under saline condition seems to cause losses in PSII efficiency, but the application of SA with 1 mM concentration is the best treatment for the alleviation of salt stress injuries on PSII activity of mung bean plants.
TL;DR: Investigations show that application of airborne photo-bioreactor culture system improves the mechanism of production of beta-carotene, and among the culture conditions, the parameters such as ambient salinity, temperature, and intensity of illumination are the most effective ones.
Abstract: Dunaliella Salina is a carotene-producing microalgae well-known for its superb ability to accumulate valuable beta-carotene. The factors affecting the bio-beta-carotene production from Dunaliella salina microalgae have been investigated in this study. First, the different usages of Dunaliella salina, especially for the production of beta-carotene, are described. Then, the factors affecting the process of obtaining beta-carotene from Dunaliella salina in the culture system, culture conditions, and downstream processes are investigated. Investigations show that application of airborne photo-bioreactor culture system improves the mechanism of production. It was found that among the culture conditions, the parameters such as ambient salinity, temperature, and intensity of illumination are the most effective ones. The optimal values for these parameters, the highest cellular density of Dunaliella salina and the highest beta-carotene production are determined. The extraction step is known as the most critical step in the downstream processes of beta-carotene production.
TL;DR: Light is thrown light on biological systems (bio-bleaching enzymes) to reduce or replace the usage of harmful bleaching chemicals for a cleaner and greener environment.
Abstract: Pulp and paper manufacturing units effectuate large amounts of waste water, causing water pollution. As the generated waste water consists perilous organo-chlorine compounds exuded during various stages of paper manufacturing, thereby meticulously impacting life. Biotechnology recommends some economical and non-polluting practices such as use of enzymes for the significant reduction in the pollution load on the water bodies. Enzymes such as Xylanase and Laccase alone or in cocktail have tremendous potential to be administered as bio-bleaching agents for they are active, renewable, non-polluting, mild, highly specific and affordable and significant for improving the grade of paper. Xylanase, the hydrolytic enzymes act on the dislocated, re-precipitated xylan onto the surface of cellulose fibres, thereby improving bleaching of paper pulp whereas Laccase, the multi-copper oxidoreductases revamp bleaching by accomplishing one electron oxidation. Sterling bio-bleaching outcome of Xylanase and Laccase alone has gained grounds for bio-bleaching via “Xylanase and Laccase” cocktail with the exception of being more economical and offering more stability. This review article throws light on biological systems (bio-bleaching enzymes) to reduce or replace the usage of harmful bleaching chemicals for a cleaner and greener environment.
TL;DR: The ever growing demand of plastic is resulting in the depletion of natural resources like petroleum as well as the amassment of waste plastics in the environment, which has driven many researchers to develop biodegradable plastics, commonly known as bioplastics.
Abstract: Plastics being synthetic polymers boast many benefits like strength, flexibility, persistence and longevity, however, being non-biodegradable they are a menace for the environment. The ever growing demand of plastic is resulting in the depletion of natural resources like petroleum as well as the amassment of waste plastics in the environment. This has driven many researchers to develop biodegradable plastics, commonly known as bioplastics. Bioplastics can serve as an environmental-friendly alternatives to harmful petroleum-based plastics, as they are synthesized from natural organic materials like polysaccharides, proteins and lipids. Starch-based bioplastics are an especially promising substitute due to the abundance, renewability, sustainability and biodegradability of starch, however more research is required to perfect bioplastics to make them economically and practically feasible.
TL;DR: In this paper, the authors used nanotechnology in producing nano-fungicides as an eco-friendly convenient approach to control leaf spot and blight symptoms caused by Alternaria alternata.
Abstract: Leaf spot and blight symptoms caused by Alternaria alternata have been widely occurred on tomatoes and potatoes in Egypt. In attempts to improve the sustainability of crop protection, the use of nanotechnology in producing nano-fungicides as an eco-friendly convenient approach was needed to control such diseases. Titanium dioxide nanoparticles (TiO2NPs) and Silver nanoparticles (AgNPs) were biosynthesized by Aspergillus versicolor KY509550 through surface resonance peaks at 340 and 400 nm, respectively. The preparation of Selenium nanoparticles (SeNPs) was done using glucose solution method at 387 nm. The sizes of the prepared nanoparticles were 47.15, 36 and 78 nm for TiO2NPs, AgNPs and SeNPs, respectively. It was detected from Transmission Electron Microscope (TEM) analysis that TiO2NPs and AgNPs were well dispersed in the solution without any agglomeration compared with SeNPs. The antifungal activity of TiO2NPs, AgNPs and SeNPs at three concentrations viz.50, 75 and 100 ppm were estimated against A. alternata by laboratory trials. The biosynthesized TiO2NPs exhibited the highest inhibitory effect at100 ppm against A. alternata and in turn resulted in 90% decrease of its mycelial growth in vitro trials. The greenhouse and field trials explored also that TiO2NPs was significantly effective in reducing disease severity (DS) as shown by the calculated area under disease progressive curve (AUDPC). SeNPs revealed close results to that obtained by TiO2NPs for both trials. AgNPs showed a moderate effect at the tested concentrations in all trials. Nanoparticles could be powerful and eco-friendly nano-fungicides for biological control of tomato leaf blight.
TL;DR: In this article, an adaptive neuro fuzzy inference system (ANFIS) model was used to predict the population of pathogenic microorganisms, chemical changes, and sensory characteristics of beef slices during 9-day storage period.
Abstract: Antimicrobial edible coatings containing natural herbal extracts and essential oil possess various benefits and are currently used to design novel active biodegradable packaging. In this study, adaptive neuro fuzzy inference systems (ANFIS) model was used to predict the population of pathogenic microorganisms, chemical changes, and sensory characteristics of beef slices during 9- day storage period. First, Cumin essential oil (CEO) was incorporated into Shahri Balangu seed mucilage (SBM) to fabricate an active and eco-friendly edible coating for beef slice. Microbial populations (based on total viable count (TVC), psychrotrophic count, Escherichia coli, coliforms, Staphylococcus aureus, and mold and yeasts) and lipid oxidation of the coated beef reduced significantly during storage period, and this was more pronounced in SBM coatings containing higher CEO concentrations. The SBM-CEO edible coating had no adverse effects on the sensory characteristics and it conferred a better texture to the product as compared to the control sample. According to the TVC results, the shelf-life of beef samples coated with SBM, SBM+0.5%CEO, SBM+1%CEO, SBM+1.5%CEO, and SBM+2%CEO were 3, 6, 9, 9, and 9 days, respectively. The coating containing 2% Cumin essential oil conferred good quality characteristics to the beef and expanded its refrigeration shelf-life. The CEO enriched SBM could be therefore employed as an active packaging to ameliorate quality attribute and microbial safety of beef and other fresh food products. In addition, ANFIS model had high R2 values (>0.84), which indicated that the designed ANFIS model had enough accuracy for predicting the qualitative and microbial properties of coated beef during storage.
TL;DR: The ligninolytic multi-copper enzyme laccase has been extensively used in industries for its versatile applications due to its catalytic properties of oxidation of both phenolic and non-phenolic lignin based compounds.
Abstract: The ligninolytic multi-copper enzyme laccase, is widely produced by bacteria and fungi. It has been extensively used in industries for its versatile applications due to its catalytic properties of oxidation of both phenolic and non-phenolic lignin based compounds. For this purpose, the enzyme needs to be produced in large quantities. Though there have been multiple reviews focused on the biochemical aspects, molecular properties and wide applications of laccases, none of them have elaborately discussed on their production, which is the prerequisite for its use. Through this review a novel attempt has been made to discuss the production strategies of laccases from mesophilic and extremophilic microorganisms using different media ingredients, agro-industrial wastes and culture conditions. These enzymes from various sources possess unique properties, yet sharing some common structural and catalytic features which can be improved using enzyme immobilization techniques. The review also outlines various applications of laccases in different industries including food, textile, paper and pulp. The enzyme has also been used for green synthesis of nanoparticles. Further, its use in biosensors and polymer syntheses have also been elaborated.
TL;DR: In this article, aqueous extract of Vitis rotundifolia (Hybrid Grapes) pulp is used for the synthesis of ZnO nanoparticles (ZnONPs).
Abstract: The growing era of nanotechnology has attracted the attention of people towards the inclusion of nanoparticles in our day to day life. The conversion of copper (Cu) and silver (Ag) into nanomaterial for biomedical application has increased the urge of working with different metallic nanoparticles. Considering these facts, zinc nanoparticles (ZnO) are synthesized using biological sources like plants, fruits, bacteria, fungi, algae etc. The introduction of biological sources for the synthesis of ZnONPs will promote a safer and non-toxic approach. The biomolecules present in biological sources act as capping or coating agents to enhance the stability and potentials of the ZnONPs. In the present study aqueous extract of Vitis rotundifolia (Hybrid Grapes) pulp is used for the synthesis of ZnO nanoparticles (ZnONPs). The structural and chemical characterization of the synthesized ZnONPs was performed using various analytical. The excitation of absorption peak at 371 nm confirmed the synthesis of ZnONPs. Morphological characterization confirmed the formation of irregular hexagonal, crystalline ZnONPs with an average size of 23.56 nm. ZnONPs were further taken for determining the photocatalytic degrading potential against Malachite Green (MG) dye. After 150 min of incubation under dark condition the dye was completely degraded. The present result clearly suggest that ZnONPs synthesized using hybrid grapes pulp extract (HGPE) could be an active candidate for removing carcinogenic and toxic chemical dyes released from textile and dye industries. Further expanding the application of HGPE-ZnONPs will promote a remarkable bioremediation application against water pollution.
TL;DR: In this paper, an in vitro study was carried out on the antifungal effect of zinc oxide nanoparticles (ZnO-NPs) obtained by a chemical route on Colletotrichum sp.
Abstract: Coffee cultivation around the world is affected by phytopathogenic fungi, among them Colletotrichum sp., the causative agent of anthracnose. In the present work, therefore, an in vitro study was carried out on the antifungal effect of zinc oxide nanoparticles (ZnO-NPs) obtained by a chemical route on Colletotrichum sp. To this end, the area of growth of the fungus exposed to the action of concentrations of 9 mmolL−1 (730 ppm), 12 mmolL−1 (980 ppm), and 15 mmolL−1 (1200 ppm) of ZnO-NPs was monitored and their behavior was compared with the effect of the fungicide, ciproconazole (positive control) as well as with a sample of the fungus that grew normally (negative control). The ZnO-NPs showed an appreciable percent inhibition of fungal growth, ~96% for the concentration of 15 mmolL−1 at 6 days, causing loss in the continuity of some hyphae and the formation of groups of hyphal structures. Additionally, the ZnO-NPs favored the formation of structures of compact appearance (similar to vacuoles) within the hypha, as well as decreasing the cytoplasmic space.
TL;DR: In this paper, an optimization of PGPR consortia and silicon fertilizer for enhanced growth and crop yield of French bean (Phaseolus vulgaris L.) was performed against saline stress.
Abstract: Increasing the yield performance of marketable horticulture crops and products using sustainable approaches has been the emergence of the 21st century. In this study, optimization of PGPR consortia and silicon fertilizer for enhanced growth and crop yield of French bean (Phaseolus vulgaris L.) was performed against saline stress. A central composite design (CCD) of RSM having face-centered (k = 1) configuration and 17 triplicated runs was designed for P. vulgaris cultivation experiments. A quadratic model having three levels of PGPR dose (X1: 8 × 107, 4.5 × 107, and, 1 × 107 cfu/g) and silicon dose (X2: 15, 10, and 5 g/kg soil) was used to optimize P. vulgaris plant height (Y1; cm), pod length (Y2; cm), pod yield/plant (Y3; g), total chlorophyll content (Y4; TCC: mg/g fwt.), superoxide dismutase (Y5; SOD: μ/mg), and catalase (Y6; CAT: μ/mg) activities. The results showed that the two selected factors (X1 and X2) had a significant influence on the selected response variables. Statistical analyses explained coefficient of determination (R2 0.05), and not-significant lack of fit values (>0.05) supportive for the validation of prediction models. The maximum plant height (40.10 cm), pod length (18.01 cm), pod yield/plant (67.95 g) and TCC (4.40 mg/g fwt.), SOD (120.19 μ/mg), and CAT (84.21 μ/mg) activities were at optimized doses of PGPR (5.52 × 107 cfu/g) and silicon (10.90 g/kg). The finding of this study suggested that the combined application of PGPR and silicon fertilizer can enhance growth, yield and biochemical activity of P. vulgaris in saline soils.
TL;DR: In this article, biogenic synthesized zinc oxide (ZnO) nanoparticles using as a nano-priming agent for enhancing seed germination and seedling growth parameters of maize (Zea mays) were determined.
Abstract: In the present study, biogenic synthesized zinc oxide (ZnO) nanoparticles using as a nano-priming agent for enhancing seed germination and seedling growth parameters of maize (Zea mays) were determined. The results of the present study carried out in paper roll towel method shown that ZnO nano-primed seeds @ 100 mg/L showed highest improved seed germination rate and seedling parameters viz., shoot length (13.0 cm), shoot width (3.4 mm); root length (20.7 cm), root width (1.0 mm); leaf length (60 mm), width (16.0 mm); vigor index (2931.9) and dry matter production (5.33 gm) than ionic control (zinc acetate) and normal control (hydro-priming). In addition, HR-SEM analysis reveals the absorption of ZnO nanoparticles on the endosperm regions of seed. Taken together, the aforementioned results also showed that the use of ZnO nanoparticles could alleviate zinc deficiency and improved the agronomical characters of maize seedling.
TL;DR: In this paper, a simple and rapid method using bacteria supernatant containing auxin complex (indole-3-acetic, IAA) and evaluated as plant nanofertilizer.
Abstract: Iron and manganese nanoparticles (NPs) were synthesized through a simple and rapid method using bacteria supernatant containing auxin complex (indole-3-acetic, IAA) and evaluated as plant nanofertilizer. Successful biosynthesis of FeOx NPs and MnOx NPs, and bimetallic MnOx/FeOx NPs were demonstrated through transmission electron microscopy (TEM), which showed the presence of spherical agglomerated NPs, and UV–visible spectroscopy, which confirmed an absorbance peak around 250–300 nm. Fourier Transform Infrared spectrometer (FTIR) revealed correspondent bands of auxin at the synthesized NPs confirming that the auxin complex acted as reductive/capping agent. In general, bimetallic MnOx/FeOx NPs from bacterial supernatant showed best result on plant growth, especially in germination rates, root growth and fresh weight in maize plantlets, and thus can be used as micronutrient nanofertilizer.
TL;DR: The findings of this work showed that volatile components of MVEO could constitute a new source for antioxidant, antidiabetic, dermatoprotective, antidermatophyte and antibacterial properties.
Abstract: The aim of this study was the investigation of the in vitro antioxidant, antidiabetic, dermatoprotective, antidermatophyte, and antibacterial properties of Mentha viridis essential oil (MVEO). Chemical composition of MVEO was determined using GC-MS analysis. Antioxidant activity was estimated by three complementary methods: DPPH, FRAP and ABTS. The in vitro antidiabetic effect was evaluated by the inhibition of α-Amylase and α-Glucosidase. Inhibitory effects of tyrosinase and elastase were used to reveal the dermatoprotective property of MVEO. Antibacterial activity was tested against five strains using agar well diffusion assay and microtitration method. The chemical composition determination of MVEO revealed the presence of carvone (37.26), 1.8-Cineole (11.82), and Terpinen-4-ol (08.72%) as the main compounds. MVEO presented remarkable antioxidant effects by IC50 values of 80.45 ± 1.86 μg/mL, 101.78 ± 3.14 μg/mL, and 139.59 ± 3.12 μg/mL obtained by DPPH, FRAP and ABTS tests respectively. In vitro inhibition of enzymes implicated in hydrocarbures degradation showed that MVEO exhibited important inhibitory effects against α-Amylase (IC50 = 101.72 ± 1.86 μg/mL) and α-Glucosidase (IC50 = 86.93 ± 2.43 μg/mL). Moreover, MVEO demonstrated remarkable inhibition of tyrosinase (IC50 = 55.13 ± 1.01 μg/mL) and elastase (IC50 = 114.24 ± 1.22 μg/mL). The antifungal activity showed important inhibitions of three dermatophyte species (T. mentagrophytes, T. tonsurans and T. violaceum). The antibacterial activity showed an important bactericidal action against tested strains, especially, Staphylococcus aureus and Listeria monocytogenes (MIC = MBC = 0.25%). The findings of this work showed that volatile components of MVEO could constitute a new source for antioxidant, antidiabetic, dermatoprotective, antidermatophyte and antibacterial properties. However, further investigations regarding the isolation of MVEO main compounds and investigations of their biological properties are required.
TL;DR: In this article, the presence of harmful heavy metals in textile dyes and selected textile effluents was evaluated and the results indicated that reactive dyes had less significance effect on seed germination and also affects the chlorophyll content.
Abstract: The present study was aimed to evaluate the presence of harmful heavy metals in textile dyes and selected textile effluents. Physicochemical parameters are the significant alarming signs of water pollution. The textile waters analyzed in the study showed elevated TSS, were samples DU1 and DU3 was recorded with 196 mg/L and 584 mg/L, which is considerably high than the permitted limit. The dyes and effluents were characterized by the presence of predominant heavy metals such as cadmium, chromium, lead, arsenic, and zinc. Phytotoxicity analysis indicated all reactive dyes had less significance effect on seed germination and also affects the chlorophyll content which directly signifies the toxic effect of dyes, whereas all four effluents showed restricted germination of seeds and also a significant reduction in chlorophyll content. Hemolytic assay implied Reactive Orange was the most toxic with 90% of RBC lysis, where effluents DU1 and DU2 showed a total RBC lysis of around 87%. Artemia salina was used to determine LC50 values of reactive dyes and textile effluents. The LC50 values of the reactive dyes signified Reactive Orange as the most toxic dye with 1.7 μg/mL of dye and among effluents DU1 exhibited higher toxicity with LC50 of 15%. The study concludes that reactive dyes and textile effluents have intolerable traces of harmful heavy metals, where seed germination and hemolytic assay signified toxic effect dyes and textile effluents. Artemia salina served as an excellent model for assessment aquatic toxicity of textile dyes and dye-containing effluents.