Nitrogen Supplementation Research Articles

Foliar N Supplementation Improves Rapeseed Transplanting Survival Rate and Yield

Transplanting shock induced by mechanical transplanting technique in dry land has a negative effect on the growth and grain yield of rapeseed (Brassica napus L.). We hypothesized that foliar nitrogen (N) supplementation plays a positive role in improving rapeseed transplanting survival rate and yield. The aim of the study was to elucidatethe morphological and physiological mechanisms of foliar N supplementation in rapeseed responding to transplanting shock. Through a 1-year pot experiment and a 2-year field experiment, foliar N supplementation at concentrations of 0, 2.5, 5.0, and 7.5 g N m−2 was set up to investigate the regulation of foliar N supplementation on the carbon (C) and N structure of seedlings before transplanting. Then we investigated the responses of morphological and physiological changes of shoot, root regeneration ability, transplanting survival rate, and grain yield to transplanting shock. The results showed that foliar N supplementation prior to transplanting increased the short-term activities of GS, GOGAT, and GDH, may improve the conversion of soluble sugar to soluble protein, increased N accumulation, and lowered the C:N ratio of rapeseed seedlings. Rapeseed seedlings with a low C:N ratio showed greater potential for root development after transplanting. Moreover, appropriate foliar N supplementation (2.5–5.0 g N m−2) not only up-regulated the positive feedback of osmoregulatory substances and antioxidant system for improving stress resistance, but also enhanced the synergistic growth of shoot and root by increasing root growth potential during transplanting shock. Therefore, the transplanting survival rate increased by 13.81–19.20%, and the grain yield increased by 25.15–30.56%. The optimal foliar N supplementation before transplanting may be used as a simple and effective agricultural measure to alleviate the negative effects of transplanting shock on rapeseed.

Soil constraints and recommendations for improving major farming in Vinh Long province, Vietnam

This study aims to assess the potential of soil and its constraints for production to meet economic needs and diversify types of crop models of Vinh Long province in the Vietnamese Mekong Delta region. Identifying the main constraints of the soil is the basis for reasonable land arrangement and proposing measures to maintain and improve the soil characteristics suitable for each crop type and purpose of use. The study used survey methods, interviewed farmers about the current farming situation and collected soil samples to analyze physical and chemical properties. Research results show that in Vinh Long, for three main crops, namely rice, fruit trees (grapefruit trees) and sweet potatoes, the primary constraints are a potential and active acid sulfate and low pH soil. In addition, Al toxicity causes phosphorus fixation, the exchangeable K content is low and the organic matter is only moderate. These limitations have affected crop productivity, especially for fruit trees. The research results also recommended improving soil properties suitable for the cultivation of major crops, including controlling the water level so as not to oxidize the sulfidic material to active acid sulfate soils, draining the water at the beginning of the season rain to leach the toxicity in the soil and need to fertilize with nitrogen, phosphorus and potassium supplements for a long time, divided into several times of application.

Application of Urea Nanoparticles in Low‐Land Rice Fields to Boost Crop Production While Maintaining Soil Fertility and Rhizospheric Health

ABSTRACTNano‐fertilizers are becoming promising in developing novel fertilization strategies while reducing the requirements of traditional fertilizers. Nano‐fertilizers have high nutrient use efficiency (NUE) and are required in small doses as compared to bulk fertilizers. The use of nano fertilizers in conjunction with a reduced dose of traditional fertilizers improves nutrient availability to plants and minimizes leaching and environmental contamination. The impact of the application of such an integrated fertilization approach on the soil fertility and microbiological population also needs to be understood. The present study investigates the influence of seven field treatments, including biogenic urea nanoparticles, as a source of N nutrient developed by TERI (referred as Teri's nano urea [TNU]), with and without conventional urea in an integrated manner. These treatments include the following: (T1)—100% recommended dose of nitrogen (RDN), (T2)—TNU alone, (T3) 100% RDN combined with TNU, (T4)—TNU at 50% concentration alone, (T5)—75% RDN combined with TNU, (T6) 50% RDN combined with TNU, and (T7) 50% RDN alone. RDF for N, P, and K used in the experiment is 140 kg/ha of urea for nitrogen fertilizer, 60 kg/ha of phosphorus, and 70 kg/ha of potassium in accordance with the local agronomic guidelines. A variable amount of urea was applied in different treatments but the recommended dose of phosphorous and potash fertilizers was applied consistently across the treatments. In different treatments, urea nanoparticles were applied as a nitrogen source via root dipping and foliar spray. The study also incorporates the economics of using nanoparticles to supplement nitrogen in an additive manner along with non‐nano macronutrient sources. Further, the influence of this novel approach of fertilization was also evaluated on the native microorganism species found in the rice fields. The results for the evaluated growth parameters, yield parameters, microbial population of soil, plant uptake, and cost economics suggest that at least 25% of the conventional urea requirement can be substituted with urea nanoparticles without causing harm to the bacterial and mycological species found in the rice agricultural fields.

Impact of Foliar Supplementation of Nitrogenous Fertilizer on Yield Attributes and Yield of Wheat (Triticum aestivum L.)

Foliar application of nitrogenous fertilizers has become a key factor in improving nitrogen use efficiency, boosting crop yields, and reducing farming costs. Liquid fertilizers are essential for precise nutrient management, ensuring crops receive the necessary nutrients throughout their growth cycle, thereby enhancing yield potential. A field experiment was conducted in the Rabi seasons of 2022-23 and 2023-24 to examine the impact of soil and foliar nitrogen supplementation on wheat growth. The experiment followed a Split Plot Design with three main plots and five subplots, each repeated thrice. The main plots included various nitrogen doses: M1 (100% recommended dose of nitrogen, RDN), M2 (75% RDN), and M3 (50% RDN). The subplots tested different foliar treatments: S1 (one spray of nano urea at the tillering stage), S2 (two sprays of nano urea at the tillering and jointing stages), S3 (two sprays of 5% urea at the tillering and jointing stages), S4 (one spray of NPK 19:19:19 at the tillering stage), and S5 (no spraying, control). The results showed that the full recommended nitrogen dose significantly improved wheat yield and related characteristics. The 100% RDN increased grain yield (4309 kg/ha), straw yield (6307 kg/ha), biological yield (10616 kg/ha), harvest index (40.58%), number of ear heads per square meter (324.39), ear head length (10.11 cm), number of grains per ear head (47.93), and 1000-grain weight (42.49 g) compared to the 75% and 50% RDN treatments. Moreover, foliar nitrogen application enhanced grain and straw yields. The highest ear head number (320.69), ear head length (9.89 cm), grains per ear head (47.44), 1000-grain weight (42.03 g), grain yield (4229 kg/ha), straw yield (6301 kg/ha), biological yield (10530 kg/ha), and harvest index (40.69%) were observed with two sprays of 5% urea at the tillering and jointing stages. This treatment performed similarly to two sprays of nano urea. Therefore, two spray of urea (5%) at tillering (45 DAS) and jointing (65 DAS) stage of wheat along with RDF would improve the performance of Wheat.

Effect of Organic Fertilizer Replacing Nitrogen Fertilizer on Major Grain Yield in China

To comprehensively assess the changing pattern of organic fertilizer substitution with nitrogen fertilizer on the yield of major grains in China, with 102 literature as the research object, through Meta-analysis we quantitatively explored the impacts of soil physicochemical properties, climatic conditions, and different nitrogen fertilizer replacement rates and supplemental application amounts. The results showed that the replacement of nitrogen fertilizer by organic fertilizer could increase crop yields compared with those from the application of nitrogen fertilizer alone, and soil quick-acting potassium content, pH, and annual average temperature had the most significant effects on the yields of the three major grains. When the nitrogen fertilizer replacement rate and the amount of supplemental nitrogen fertilizer applied were 31.06% and 241.78 kg·hm-2, 26.52% and 173.31 kg·hm-2, and 39.23% and 149.17 kg·hm-2, the optimum yield increase ratios of 3.31%, 3.32%, and 1.08% were achieved for maize, wheat, and rice, respectively. Thus, the results of this study can provide a reference basis for rational fertilizer application in future crop production and help promote green agriculture.

Deciphering the role of substrate carbon to nitrogen ratio in preventing orange mold contamination caused by Neurospora sitophila in mushroom cultivation

IntroductionMold contamination, particularly from green and orange molds, poses a serious threat during the growing stage in mushroom cultivation, exacerbated throughout the hot and humid summer months. Despite extensive studies on green mold, orange mold remains underexplored. Consequently, this study comprehensively investigated orange mold contamination, focusing on identifying the causal agent, assessing its pathogenicity, and exploring potential countermeasures.MethodsInternal transcribed spacer (ITS) region sequencing was used to confirm the causative entity, while the dual confrontation plate method was employed to assess pathogenicity. Furthermore, control strategies, including plant extract, in vitro media performance, and substrate characteristics, were explored. For estimated substrate qualities, Fourier-transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM) studies, along with analysis of physicochemical properties including the C:N ratio, carbon, protein, and mineral content were assessed.ResultsThe result confirmed Neurospora sitophila as the causal entity. The pathogenicity assessments indicated that this mold impedes the colonization of mushroom mycelium by competing for nutrients and space. The in-vitro studies of media performance demonstrated that Neurospora sitophila growth was inhibited at varying rates in nitrogen supplemented media in the presence of available carbon. Notably, SEM analysis revealed Neurospora sitophila heavily colonized sawdust but not rice straw, attributed to a higher C:N ratio in sawdust.DiscussionThese findings suggest that lower C:N ratio negatively affects orange mold growth, highlighting nitrogen supplementation in sawdust or using rice straw as effective strategies to manage orange mold contamination in mushroom cultivation. This strategy could also be applied to other food industries where Neurospora is used.

Effects of concentration of NPK fertilizer as a Nitrogen Source in fermentation of Bioethanol

Bioethanol is a versatile raw material widely used in the production of ethanol derivatives, pharmaceuticals, fuel additives, alcoholic beverages, solvents, and medicines. Its production involves a fermentation process that can be optimized by adjusting nutrient concentrations. This study investigates the effects of NPK fertilizer concentration as a nitrogen source on the yield and density of bioethanol produced from sugarcane fermentation. The concentrations of NPK fertilizer tested were 0.00%, 0.10%, 1.00%, and 2.00%. The results indicate that low concentrations of NPK, particularly 0.10%, significantly enhanced ethanol production, achieving the highest bioethanol yield of 3.71%. This increase in yield is attributed to the essential nutrients provided by NPK, which support microbial growth and fermentation efficiency. However, as NPK concentration increased to 1.00% and 2.00%, ethanol yield sharply declined to 1.24% and 1.20%, respectively, likely due to osmotic stress and the proliferation of non-ethanol-producing microorganisms, which hindered fermentation efficiency. Regarding bioethanol density, no significant differences were observed across the varying NPK concentrations, with values ranging from 2.31 g/mL to 2.33 g/mL, suggesting that nitrogen supplementation does not influence the physical properties of the bioethanol. The density of the bioethanol produced was far higher than the Indonesian National Standard for fuel-grade ethanol, indicating the need for further purification processes, such as distillation or dehydration, to meet quality standards. These findings highlight the importance of optimizing NPK fertilizer concentrations to maximize ethanol yield while emphasizing the role of post-fermentation treatments for improving bioethanol quality

The Effects of Changing Environments, Abiotic Stresses, and Management Practices on Cropland Evapotranspiration: A Review

AbstractThe significance of crop evapotranspiration (ETa) to climate science, agronomic research, and water resources is not in dispute. What continues to draw attention is how variability in ETa is driven by changing environments, abiotic stresses, and management practices. Here, the impacts of elevated CO2 concentration (e[CO2]), elevated ozone concentration (e[O3]), warming, abiotic stresses (water, salinity, heat stresses), and management practices (planting density, irrigation methods, mulching, nitrogen application) on cropland ETa were reviewed, along with their possible causes and estimation. Water and salinity stresses, e[O3], and drip irrigation adoption generally led to lower total growing–season ETa. However, total growing–season ETa responses to e[CO2], warming, heat stress, mulching, planting density, and nitrogen supplement appear inconsistent across empirical studies. The effects of e[CO2], e[O3], water and salinity stresses on total growing–season ETa are attributed to their influence on stomatal conductance, root water uptake, root and leaf area development, microclimate, and potentially phenology. Total growing–season ETa in response to warming is affected by variations in ambient growing–season mean air temperature and phenology. The differences in crop ETa under varying planting densities are due to their differences in leaf area. The responses of ETa to heat stress, mulching, and nitrogen application represent trade–off between their opposite effects on transpiration and evaporation, along with possibly phenology. Modified ETa models currently in use can estimate the response of ETa to the many aforementioned factors except for e[O3], heat stress, and nitrogen application. These factors offer a blueprint for future research inquiries.

Production of L-Asparaginase using Soil Isolate of Cladosporium sp. and Evaluation of its Antitumor and Antioxidant Activities

The enzyme L-asparaginase is given prime attention in healthcare settings owing to its significant therapeutic applications in oncology. The present study isolated five different species of fungi belonging to the genera Aspergillus (23.8 and 9.5%), Cladosporium (19%), Fusarium (14.3%) and Penicillium (19%) from soil samples. Screening on Czapek Dox’s medium indicated that the isolate Cladosporium sp. ASP4 exhibit higher potential of synthesizing L-asparaginase than other fungi by means of causing a halo zone measuring 22.3 mm dia. Fermentation of standard medium ingredients along with the solid substrate soya bean meal by the potential fungal isolate resulted in the production of 20.53 IU/mL of L-asparaginase. Optimization studies deciphered the carbon source sucrose, supplementary nitrogen ammonium nitrate, pH ≥8.0 and the temperature 50oC as favorable process parameters for the enzyme production. Purified L-asparaginase of the present study demonstrated moderate antineoplastic activity against the A549 lung cancer cells with the IC50 values of ≥50 IU/mL. The enzyme displayed better antioxidant property compared to those of previous studies by way of scavenging the radicals with the SC50 values of ≥250 mg/mL. These findings encourage carrying out further elaborate studies for prospective biotechnological and pharmaceutical applications of the purified enzyme.

Overproduction of Cucurbitadienol through Modular Metabolic Engineering and Fermentation Optimization in Saccharomyces cerevisiae.

Cucurbitadienol is a key intermediate in the biosynthesis of cucurbitane-type compounds and serves as a precursor for mogrosides, cucurbitacins, and other valuable natural products of potential biological and food importance. However, microbial fermentation for cucurbitadienol production remains inefficient, limiting its potential for further industrial application. This study achieved the efficient synthesis of cucurbitadienol through a multimodular strategy. First, an N-degron tag was used to direct metabolic flux toward cucurbitadienol synthesis without compromising cell growth. Second, enzyme engineering strategies were employed to improve the utilization efficiency of intermediate metabolites. Finally, to increase precursor availability, the transcription factor UPC2-1 was introduced, which upregulated the expression of ERGs in the pre-squalene pathway. After eliminating nitrogen supplementation and optimizing fermentation conditions, cucurbitadienol accumulation in the 5 L bioreactor increased to 6.1 g/L, representing the highest titer reported to date. These findings provide a solid foundation for the industrial-scale production of cucurbitadienol and its derivatives.

Growth of Sea Grapes (Caulerpa lentillifera) in Laboratory-Scale Cultivation With Urea As A Single Nitrogen Nutrient

Sea grape (Caulerpa lentillifera) is a strategic green macroalgae with significant potential in aquaculture and functional food industries. However, its cultivation remains constrained by limited production techniques. This study investigated the influence of nitrogen concentration on C. lentillifera growth in a laboratory-scale cultivation system. A completely randomized experimental design was implemented with four treatments: a control group (0 ppm) and nitrogen supplementation levels of 5, 10, and 15 ppm, each replicated thrice over 21 days. Results demonstrated a significant positive correlation between nitrogen concentration and growth parameters. The 15 ppm nitrogen treatment exhibited the highest absolute growth (3.37 g), relative growth rate (13.50%), and specific growth rate (1.82% per day). Interestingly, no statistically significant difference was observed between 10 and 15 ppm treatments, suggesting a potential nitrogen uptake saturation point. Water quality parameters remained stable throughout the experiment, with temperature ranging from 28-30°C, salinity at 33-34 ppt, dissolved oxygen between 5.9-6.7 ppm, and pH maintained at 7.5-7.8. The study provides crucial insights into nitrogen's role in C. lentillifera cultivation, offering a scientific foundation for developing more efficient and sustainable macroalgae production strategies in aquaculture and functional food industries.

The amendment value of pulp and paper mill sludges in Finnish coarse-textured soil

The amendment value of pulp and paper mill sludges in Finnish coarse-textured soil

A comprehensive evaluation of bioremediation effects of oil-contaminated soils using various dosages of exogenous nitrogen supplementation: TPH removal, ecological toxicity, and microecological response

A comprehensive evaluation of bioremediation effects of oil-contaminated soils using various dosages of exogenous nitrogen supplementation: TPH removal, ecological toxicity, and microecological response

Organic waste and beechwood cellulose blend saccharification and validation of hydrolysates by fermentation

This study demonstrates the sustainable advancement of fermentation media by blending the organic fraction of municipal solid waste (OFMSW) with organosolv beechwood cellulose. Investigations examined the effects of enzyme dosages and OFMSW integration into organosolv beechwood cellulose on sugar yield. The findings indicate that OFMSW inclusion and Cellic® CTec3 dosage significantly influence hydrolysis across two different batches of beechwood cellulose. Experimental data showed that OFMSW inclusion levels of 35% and 45% (w/w) produced sugar levels comparable to pure beechwood cellulose, achieving 58% to 68% (w/w) saccharification with sugar concentrations of 44 to 46 g/L. This highlights OFMSW's potential as a buffer substitute during the enzymatic conversion of organosolv cellulose. The resulting sugar-rich hydrolysates, derived from OFMSW-cellulose blends and pure cellulose, were evaluated for ethanol and cell biomass production using Saccharomyces cerevisiae and Mucor indicus, yielding 30 g of ethanol/L hydrolysate. Furthermore, OFMSW inclusion in beechwood cellulose proved to be an excellent alternative to synthetic nitrogen agents for S. cerevisiae cell production, reaching 12.2 g of biomass/L and surpassing the biomass concentration from cultivation on cellulose hydrolysate with nitrogen supplementation by threefold. However, M. indicus did not grow in the OFMSW-cellulose blend, suggesting that the inhibitory compounds of OFMSW may be a bottleneck in the proposed process. The present study demonstrates the benefits of incorporating OFMSW into cellulose material, as it enhances both cost-effectiveness and sustainability. This is attributed to the natural buffering properties and nitrogen content of OFMSW, which reduces the need for synthetic agents in fermentation-based lignocellulose biorefineries.Key points• OFMSW inclusion significantly influences beechwood cellulose saccharification.• OFMSW could be an excellent alternative for synthetic agents in biorefinery.• S. cerevisiae achieved higher biomass growth on OFMSW/cellulose mix compared to YPD.Graphical abstract

The New Technology for In Vitro Culture with Induction of Nanobubbles (NBsN2 and NBsO2) in Cattleya sp.

The growth and development of orchids take a relatively long time, while the demand for high-quality orchids continues to increase significantly. Tissue culture is a technique of isolating plant parts in organs, tissues, and cells and then culturing these plants on artificial media in a sterile environment. Tissue culture techniques can reproduce plants in a relatively short time, with the same properties and quality, so efforts to optimize tissue culture with technology are the right solution, one of which is using nanogenerator technology that produces Nanobubbles (NBs). NBs are one of the nanotechnologies that are ?100 nm in size with induced gas needed by plants. This study aims to determine the effectiveness of growth and development from the induction of NBsN2 and NBsO2 in Cattleya sp. planlet in vitro culture. This research method uses in vitro culture with a Randomized Group Design. The results of the MsO treatment showed higher weight than other treatments, with a total plant weight value of 0.3550 g and a total plant height value of 1.3983 cm. Murashige-Skoog + NBsNitrogen (MsN) treatment showed higher root length than other treatments with a total value of 1.2367 cm. In the treatment of Ms, MsO, OJ and NJ, a live percentage of 83-100% was observed. The statistical test results indicate that NBs positively affect Cattleya sp. plantlets. This effect includes increasing plant weight, height, and root length and promoting new shoots growth. Additionally, nitrogen supplements play a role in colour changes, indicating the plant's health and photosynthetic efficiency. In the treatment with Induction O2, the initial colour changes from Strong Yellow Green (141 D) to Strong Yellowish Green (141 C), while in the treatment with Induction NBsN2, the initial colour changes from Strong Yellow Green (141 D) to Deep Yellow Green (141 B).

The role of proton excreted by Advenella kashmirensis DF12 during ammonium assimilation in phosphate solubilization.

Phosphate-solubilizing bacteria (PSB) can solubilize soil fixed phosphorus (P) to plant available forms. In previous studies, the mechanisms of inorganic phosphate solubilization by PSB mostly focused on the acidolysis of organic acids. Here we screened a highly efficient PSB, Advenella kashmirensis DF12, with the maximum P solubilization of 590 mg L- 1 at 6 days. In addition to its P solubilizing ability, DF12 also showed a tolerance to pH from 5 to 10 and a nitrogen fixation potential. The multiple functions of DF12 and its wide adaptability to various environmental conditions make it a promising biofertilizer candidate. The combined analysis of extracellular metabolites and intracellular metabolome data revealed that the production of organic acid (mainly gluconic acid) is not the only mechanism of P solubilized by DF12, the solubilized P content was not correlated with the gluconic acid concentration but was in a highly significant positive correlation with proton concentration, extrusion of proton during NH4+ assimilation plays a key role in phosphate solubilization. Moreover, the contribution of NH4+ assimilation to phosphorus solubilization is generally present in PSB. Therefore, we proposed that applying ammonium fertilizer in P-deficient soil is more appropriate, it can not only supplement nitrogen fertilizer, but also enhance P use efficiency, which contributes to worldwide fertilizer use reduction and efficiency improvement.

Domestication of wild-growing Turkey tail mushroom (Trametes versicolor) from Ethiopian forests on augmented agro-industrial byproducts

Despite being extensively studied as a white-rot fungus, there have been no efforts to explore and cultivate the high-yielding wild Trametes versicolor strains in Ethiopia. Thus, this study was initiated to assess the growth performance of T. versicolor on various growth media. Accordingly, ten substrates (S1–S10) were formulated by a combination of agro-industrial by-products that mainly constituted sugarcane wastes and animal manures. The effect of substrates on yields, biological efficiencies, and nutritional compositions was examined. The mushroom developed a white mycelium on the growth media. T. versicolor cultivated on the S5 blend, comprising 80% sugarcane bagasse, 12% horse manure, and 8% poultry manure, exhibited the most substantial fruiting body yield (158.33 g/500 g bag) and the highest biological efficiency (31.5%), with an optimal C:N ratio of 31:1. It has shown good mycelial growth, short colonization, and short pinhead formation time compared to other substrates. S7, lacking nitrogen supplementation, yielded low biological efficiency and fruiting bodies at 11.50% and 57.67%, respectively. The crude protein, fiber, low fat, and carbohydrate content ranged from 7.46 to 14.65%, 12.89 to 18.38%, 0.42 to 0.53%, and 48.75 to 66.75%, respectively. Notably, the highest nutritional values, excluding carbohydrates, were obtained from S5, while the sugarcane bagasse had the highest carbohydrate content among substrates. Consequently, S5 emerged as a suitable medium for cultivating wild T. versicolor mushrooms, particularly in regions abundant in poultry, horse manures, and sugarcane bagasse. Therefore, S5 represents an optimal substrate for T. versicolor cultivation, offering improved productivity and nutritional quality at reduced costs.

Different Nitrogen Levels with Nano and Prilled Urea Spray on Productivity and Profitability of Maize (Zea mays L.) in alfisols of Jharkhand

A ground-breaking and enduring way to significantly reduce the use of conventional nitrogen fertilizer is to use nano-urea as a nitrogen supplement. The combination of nano and prilled urea was investigated in this study to address this issue and allowing for a 25% reduction in the recommended urea dosage. Research on rainfed maize during kharif season was conducted at ICAR-IARI Jharkhand. Twelve different combinations of conventional prilled urea, nano and prilled urea spray were investigated in the study. In the fields, the experiment used a randomized block design. Different treatments included applying prilled urea as a 2% solution in 150 liters of water per hectare and nano-urea at a rate of 1250 ml/acre applied twice through foliar application. Results showed that applying two additional applications of nano-urea along with 75% of the recommended dose of prilled-urea was the most successful fertilization strategy. This performed statistically equal with both the 100% recommended dose and the 100% recommended dose with two prilled urea spray applications in terms of yield, and cost-to-benefit ratio. The study's findings show that nano-urea can safely replace at least 25% of the dosage of prilled urea i.e. recommended, providing a more profitable and environmentally friendly method of cultivation.

Biological characteristics of marine Streptomyces SK3 and optimization of cultivation conditions for production of compounds against Vibiriosis pathogen isolated from cultured white shrimp (Litopenaeus vannamei).

Antibiotic resistance in shrimp farms has emerged as an extremely serious situation worldwide. The main aim of this study was to optimize the cultural conditions for producing new antibiotic agents from marine Streptomyces species. Streptomyces SK3 was isolated from marine sediment and was identified by its 16S rDNA as well as biochemical characteristics. This microbe produced the highest concentration of bioactive secondary metabolites (BSMs) when cultured in YM medium (YM/2). It produced the maximum total protein (41.8 ± 6.36 mg/ml) during the late lag phase period. The optimum incubation temperature was recorded at 30 °C; BSMs were not produced at ≤10 °C within an incubation period of 3-4 days. The suitable agitation speed was found to be 200 rpm with pH 7.00. The proper carbon, nitrogen, and trace elements supplementation consisted of starch, malt extract, calcium carbonate (CaCO3), and magnesium sulfate (MgSO4). The ethyl acetate extract was found to act strongly against three vibriosis pathogens, Vibrio harveyi, Vibrio parahaemolyticus, and Vibrio vunificus, as indicated by the inhibition zones at 34.5, 35.4, and 34.3 mm, respectively. The extract showed the strongest anti-V. harveyi activity, as indicated by minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) values of 0.101 ± 0.02 and 0.610 ± 0.04 mg/ml, respectively. Basic chemical investigation of the crude extract using thin layer chromatography (TLC), bioautography, liquid chromatography tandem mass spectrometry (LC‒MS/MS), Fourier transform infrared spectroscopy (FTIR), and proton nuclear magnetic resonance (1H-NMR) revealed that the active components were the terpenoid and steroid groups of compounds. They showed carboxylic acid and ester functions in their molecules.

Functional whey-based drinks with grape pomace extract and fruit juice

Industrial waste leads to pollution and deterioration of the environment, as well as harming the living population and animals. Whey, being a by-product of milk processing, is a source of protein and nitrogenous compounds, carbohydrates, lipids, mineral supplements, vitamins, organic acids, enzymes and macro- and microelements. Amino acid content of whey is represented by amino acids of protein substances and free amino acids. The next valuable secondary raw material is grape pomace, which is practically not processed and becomes a factor of anthropogenic load, polluting the environment. Grape pomace has a rich chemical composition, especially a large number of phenolic compounds, which have antioxidant properties. Currently, there is a significant increase in the production and consumption of soft drinks with various additives, the composition of which is replete with unnecessary colors and flavors. The aim of the work is to use milk whey for the development of technology of drinks of functional purpose, which will directly increase the efficiency of its processing, as a secondary raw material in industrial production, as well as serve the purpose of improving the environmental situation in places where milk processing plants are located. In particular, the creation of functional drinks on the basis of milk whey with the addition of grape pomace, fruit juices and pectin, will enrich the milk drink with a complex of biologically active substances, trace elements, antioxidants, vitamins. Using organoleptic and physico-chemical parameters, two technologies of functional drinks based on milk whey with 25% Husein Black grape pomace extract, in the first 25% cherry and in the second 25% peach juices were developed. The first formulation demonstrated noteworthy macro- and microelement content, including calcium (12.10%), sodium (5.04%), magnesium (1.60%), phosphorus (7.31%), and potassium (24.61%). Similarly, the second formulation exhibited significant macro- and microelement composition, including calcium (9.50%), sodium (4.28%), magnesium (1.33%), phosphorus (6.37%), and potassium (21.91%). All microbiological indicators meet the requirements of GOST and indicate the absence of pathogenic microflora, which is one of the indicators of guaranteed sanitary well-being of the proposed products. The developed drinks have pleasant organoleptic indicators, high biological value and low cost price.