Isolation and Characterization of a PEG-degrading and Mo-reducing Escherichia coli strain Amr-13 in soils from Egypt

Molybdenum is a pollutant that shows toxicity to spermatogenesis while polyethylene glycols (PEG) are used predominantly in detergents. The pollution of molybdenum and PEGs are reported worldwide. We have isolated ten molybdenum-reducing bacterial isolates from soil that can reduce molybdenum (sodium molybdate) into the colloidal molybdenum blue (Mo-blue). The screening of these isolates for PEG-degrading ability showed that one isolate was capable to utilize PEG 200, 300 and 600 for optimal conditions were pHs between 5.5 and 8.0, temperatures between 30 and 37 oC, phosphate at 5 mM, molybdate between 10 and 30 mM, and glucose as the electron donor. Biochemical analysis of the bacterium identifies it as Escherichia coli strain Amr-13. Growth was best supported by all PEGs at concentrations of between 600 and 1,000 mg/L. A complete degradation for PEG 200 and PEG 300 at 1,000 mg/L was observed on day four and five, respectively, while nearly 90% of PEG 600 was degraded on day six. The growth of this bacterium on these PEGs was modelled using the modified Gompertz model, and produced growth parameters values, which were maximum specific growth rates of 1.51, 1.45 and 1.18 d-1 and lag periods of 0.53, 0.87 and 1.02 day for PEG 200, PEG 300 and PEG 600, respectively. PEG 200 was the most preferred substrate for this bacterium, while PEG 600 was the least preferred.

STUDY OF THE PROCESS OF OXIDATIVE DESULFURIZATION OF DIESEL FUEL IN THE PRESENCE OF CO-CATALYSTS

Continuous growth in consumption of oil in the world, as well as ever-increasing quality requirements stimulate the search for new scientific and technological solutions to directionally affect the characteristics of petroleum products, including their chemical composition. The advantages of oxidative desulfurization before hydrotreating are the absence of the need to use hydrogen, as well as small capital and energy costs, since the method does not require high temperatures and pressures. The purpose of this work was to study the oxidation process of diesel fuel and to search for the optimal mode of oxidative desulfurization of diesel fuel in the presence of transition metals salts with the addition of mineral acids. The object of the study is a straight-run diesel fraction of the Pavlodar Petrochemical Plant with boiling temperatures of 180-350°C. The oxidation process was carried out with hydrogen peroxide in the presence of salts of the transition metals molybdenum, vanadium and tungsten. The article defined the basic physico-chemical characteristics of straight-run and desulfurized diesel fractions. The optimal catalyst (Na2MoO4) was selected at a molar ratio of metal to sulfur of 1:100 for the oxidation process of straight-run diesel fractions. As a result of oxidative desulfurization of diesel fuel in the presence of sodium molybdenum perox complexes, the total sulfur content decreased by 42.9%, and with the addition of sulfuric acid by 56.5%. An increase in the cetane index from 56.3 to 58.6 was revealed in the presence of sodium molybdate with the addition of sulfuric acid.

Effect of Seed Priming Treatments with Panchagavya, Jeevamrutha, Beejamrutha and Leaf Extracts, Sodium Molybdate on Seed Quality Parameters of Field Pea (Pisum sativum)

The present research study was conducted at the Seed testing laboratory of Sam Higginbottom Institute of Agriculture Technology and Sciences, Prayagraj, Uttar Pradesh in 2020-2021. The research study revealedthat effect of seed priming treatments with Panchagavya, Jeevamrutha, Beejamrutha and leaf extracts, Sodium molybdate on seed quality parameters of field pea was analyzed through Completely Randomized Design (CRD). Organic treatments are designated as Panchagavya 3% and 5%, Jeevamrutha 3% and 5%, Beejamrutha 5% are used as treatment 8Hrs respectively, botanical treatments are Tulasi leaf extract 6%, Lantana camara leaf extract for 6% are used as treatment for duration of 4 hours respectivelyin which the treatment T8- Sodium molybdate (3%) for 3 Hrs exhibited higher mean value for seed germination (76.75%), root length (6.49 cm), shoot length (7.84 cm), seedling length (14.33 cm), seed vigour index -I (1099.68) and Followed by value was exhibited by T6-Tulasi Leaf Extract (6%) with respect of Root length (6.79 cm)Seedling dry weight (1.725 g), Seed Vigour Index II (129.78), T0 (control) with respect of Germination percentage (71.75%) root length (6.30 cm), shoot length (6.60 cm) and seedling length (12.90 cm), seed vigour index I &II (925.60 & 98.13).

Effect of Foliar Nutrition and Crop Geometry on Cultivars of Blackgram in Shiwalik Foothills of Jammu

Background: Rapid expansion in population increased the global food demand. To meet this surge in demand for food and to ensure food and nutritional security addition of pulses in the cropping system is a visible alternative. Pulses intensifies cropping intensity, enhances health and fertility status of the soil and acts as a good source of dietary protein etc. However, due to a wide gap between the potential and actual yield of pulses in rainfed areas. Hence, identification and adoption of best management practices has become a pre-requisite. The present study was undertaken as the information available on foliar nutrition and different crop geometries on performance of different blackgram genotypes in rainfed condition is meagre. Methods: In this investigation conducted during kharif season of 2018 at Advanced Centre for Rainfed Agriculture, SKUAST-Jammu, Rakh Dhiansar. The experiment was laid out in factorial randomized block design with 3 factors and 3 replications. The factor-1 consisted of three blackgram cultivars (Uttara, PU-31 and Mash-114), factor 2 consisted of two crop geometries (30×10 cm and 45×10 cm) and factor-3 consisted of three foliar nutrition (Foliar spray of molybdenum as sodium molybdate @ 0.1% at 20 DAS, Foliar spray of 1.5% KCl at flowering and Foliar spray of molybdenum as sodium molybdate @ 0.1% at 20 DAS fb 1.5% KCl at flowering). Result: The results from the present investigation indicated that adoption of Mash-114 at 30×10 cm crop geometry, supplemented with foliar application of molybdenum as sodium molybdate @ 0.1% at 20 DAS fb 1.5% KCl at flowering could be a viable technological proposition under rainfed conditions of Jammu.

Effect of Seed Treatment and Nutrient Schedule on the Productivity of Blackgram (Vigna mungo L.)

Background: Blackgram (Vigna mungo L.) is an important short duration crop and is grown throughout the country. Seed treatment can improve seedling establishment and better crop stand; it also improves plants ability to tolerate stress at early growth stages and foliar application has the advantage of quick and efficient utilization of nutrients, elimination of nutrient losses through leaching and fixation in soil and also helps in regulating the uptake of nutrients by plants thus improving productivity. Methods: A field experiment was conducted during rabi 2018 at the Instructional Farm, College of Agriculture, Vellayani, Thiruvananthapuram to assess the effect of different levels of seed treatments and nutrient schedule on the growth and yield of blackgram. The growth attributes, yield attributes and yield viz., number of pods per plant, seeds per pod, length of pod, 100 seed weight, grain yield, haulm yield and harvest index were favorably influenced by the treatments. Result: Seed treatment with borax @ 1 g kg-1 seed and sodium molybdate @ 1 g kg-1 seed were observed superior in increasing plant height (135.84 cm), number of trifoliate leaves per plant (7.61), pods per plant (24.16), length of pod (5.23 cm), 100 seed weight (6.74 g), grain yield (1005 kg ha-1) and harvest index (0.38). Significantly higher nodule number (41.83), effective nodule number (33.83) and weight of nodules (58.83 mg) plant-1 at flowering were documented with sodium molybdate @ 1 g kg-1 seed. In case of seeds per pod significantly higher number of pods per plant (7.33) was observed with borax @ 2 g kg-1 seed and maximum haulm yield (1854 kg ha-1) reported with sodium molybdate @ 1 g kg-1 seed. The basal application of ½ N + full P + ½ K followed by ½ N and ½ K as foliar spray of 13:0:45 at 15, 30, 45 and 60 DAS produced significantly more 100 seed weight (6.52 g), grain yield (872 kg ha-1) and haulm yield (1750 kg ha-1). Interaction effect of boron and molybdenum also showed significant influence with respect to yield attributes and yield.

Optimisation of Various Physicochemical Variables Affecting Molybdenum Bioremediation Using Antarctic Bacterium, Arthrobacter sp. Strain AQ5-05

The versatility of a rare metal, molybdenum (Mo) in many industrial applications is one of the reasons why Mo is currently one of the growing environmental pollutants worldwide. Traces of inorganic contaminants, including Mo, have been discovered in Antarctica and are compromising the ecosystem. Bioremediation utilising bacteria to transform pollutants into a less toxic form is one of the approaches for solving Mo pollution. Mo reduction is a process of transforming sodium molybdate with an oxidation state of 6+ to Mo-blue, an inert version of the compound. Although there are a few Mo-reducing microbes that have been identified worldwide, only two studies were reported on the microbial reduction of Mo in Antarctica. Therefore, this study was done to assess the ability of Antarctic bacterium, Arthrobacter sp. strain AQ5-05, in reducing Mo. Optimisation of Mo reduction in Mo-supplemented media was carried out using one-factor-at-a-time (OFAT) and response surface methodology (RSM) approaches. Through OFAT, Mo was reduced optimally with substrate concentration of sucrose, ammonium sulphate, and molybdate at 1 g/L, 0.2 g/L, and 10 mM, respectively. The pH and salinity of the media were the best at 7.0 and 0.5 g/L, respectively, while the optimal temperature was at 10 °C. Further optimisation using RSM showed greater Mo-blue production in comparison to OFAT. The strain was able to stand high concentration of Mo and low temperature conditions, thus showing its potential in reducing Mo in Antarctica by employing conditions optimised by RSM.