Role of Nitrogen Source for L-Glutaminase Production from Fungal Strain using through Submerged Fermentation

The biomass yield, cellulolytic activity, and protein recovery using Aspergillus terreus GN1 with alkali-treated sugarcane bagasse was studied using different levels (250-600 mg of N/L of broth) of organic and inorganic nitrogen sources. e.g., cattle urine, urea, cornsteep liquor, ammonium sulfate, ammonium nitrate, ammonium iron sulfate, ammonium chloride, and sodium nitrate. Among different levels of alkali-treated bagasse substrate concentrations (0.5-4.0% w/v) tested, 1.0% substrate yielded the highest crude protein content, protein recovery, and cellulolytic activity. The biomass recovery with 1.0% substrate ranged from 290-380 mg/500 mg bagasse substrate in a 50-mL broth with a nitrogen level of 250-600 mg of N/L in all the sources except ammonium iron sulfate, which yielded 402-439 mg/500 mg bagasse substrate. However, crude protein content of biomass obtained with an ammonium iron sulfate nitrogen source was the lowest. Cornsteep liquor nitrogen source at the rate of 600 mg of N/L yielded the maximum crude protein of 32.9%, protein recovery of 22.2 g/100 g of bagasse, and carboxymethyl cellulase and filter paper enzyme activities of 1.1 and 0.09 units/mL, among the organic and inorganic nitrogen sources studied. In general, the organic nitrogen sources and inorganic nonammonium nitrogen sources were utilized preferentially for protein production over the inorganic ammonium nitrogen sources. The fermentation time required under optimum cultural and nutritional conditions for A. terreus GN1 was also evaluated. The crude protein content of the biomass increased gradually up to the seventh day of fermentation, but the protein recovery rate was high up to two or three days. It was observed that the cellulose utilization rate increased after an initial lag of one day up to the third day and gradually increased further, which corresponded positively with protein content, biomass protein recovery, and cellulase enzyme activity. On the seventh day of fermentation, the crude protein content, biomass protein recovery, water-soluble carbohydrate, bagasse cellulose utilization, CMCase, and FPase activities were 32.8%, 20.1 g/100 g of bagasse, 6.2%, 82.7%, 1.0. and 0.08 U/mL, respectively. The final biomass recovered contained 32.8% crude protein content and had an in vitro rumen digestibility (IVRD) coefficient of 68.8%. The biomass contained almost all the essential and nonessential amino acids and was comparable with FAO reference protein. It is concluded that a fermentation time of 72 h gave a faster rate of protein production of 16.9 g/100 g of bagasse with 69.8% bagasse cellulose utilization with 76.0% IVRD. and contained almost all the essential and nonessential amino acids.

The main aim of the study is to enhance the biosynthesis of xylanse by incorporating nitrogen sources (both organic and inorganic). Recently, xylanases have expanded their use in many processing industries, such as pulp and paper, food and textile to newer needs such as biofuel production. .This study were taken up to the enhance the biosynthesis of xylanase by supplementation of organic nitrogen and inorganic nitrogen sources were employed in range of 0.25% to 1.25%. The organic nitrogen source were supplemented are peptone, yeast extract and beef extract and inorganic nitrogen sources are ammonium sulphate, ammonium chloride and ammonium nitrate. The yeast extract and ammonium nitrate were yielded higher xylnase production and showed 5.56 IU and 5.79 IU Key words: Xylanase, submerged fermentation, yeast extract, ammonium nitrate and assay.

Recently, xylanases have expanded their use in many processing industries, such as pulp and paper, food and textile to newer needs such as biofuel production. .This study were taken up to the enhance the biosynthesis of xylanase by supplementation of organic nitrogen and inorganic nitrogen sources were employed in range of 0.25% to 1.0%. The organic nitrogen source were supplemented are peptone, yeast extract and beef extract and inorganic nitrogen sources are ammonium Sulphate and ammonium chloride. The beef extract and ammonium nitrate were yielded higher xylnase production and showed 7.5 IU and 8.46 IU Key words: Xylanase, submerged fermentation, xylose, fermentation kinetics and inoculums size

Some fungi in the Chytridiomycota can assimilate both inorganic and organic sources of nitrogen

Sclerotial blight of tea (Camellia sinensis L.) caused by Sclerotium rolfsii Sacc. is one of the destructive diseases in tea growing areas of the world. In the present investigation, an attempt was made to know the optimum conditions for the mycelial growth of S. rolfsii. Factors influencing mycelial growth of S. rolfsii were studied with special reference to their growth in different media, variable pH and variable sources of carbon (viz., 6 types) as well as organic (viz., 4 types) and inorganic (viz., 4 types) nitrogen sources. Maximum growth of pathogen occurred after 8 days of inoculation at pH 6. Dextrose was the most effective carbon source and yeast extract (organic source) was found most optimum for growth of S. rolfsii. Organic nitrogen sources were found to be better than inorganic nitrogen sources. DOI: http://dx.doi.org/10.3126/njbs.v1i0.7466 Nepalese Journal of Biosciences 1: 26-31 (2011)

Humicola sp . SKESMBKU03, a cellulase producer was isolated from horse dung manure collected from Hyderabad, Telangana. In the present study, endo and exoglucanase production from Humicola sp . SKESMBKU03 was studied and optimization of the cultural conditions to enhance production of enzymes has been reported. Among the twenty fungal cellulase producers isolated from different thermogenic habitats, the fungal strain ‘HD3’ identified as Humicola sp . SKESMBKU03 exhibited highest cellulase activity by plate screening assay. To enhance the production level of the enzyme, different cultural conditions were optimized and observed that optimum pH and temperature for endo and exoglucanase production was 5.0 and 45 o C respectively. Maximum growth as well as enzyme production was recorded on 3rd day of incubation period in shake flask (100RPM) containing Mandel’s Weber medium. Urea and malt extract among the organic nitrogen sources while ammonium chloride as inorganic nitrogen source were found to be the best nitrogen source (0.2%) for endo and exoglucanase production. The endo and exoglucanase activities are higher in media containing glucose as their carbon source (1%) followed by xylose and lactose. The organism showed maximum dry weight in pH of 9.0-10.0, temperature of 45 o C, cellulose as carbon sources, yeast extract and malt extract of nitrogen source. The endo and exocellulases produced by the Humicola sp. SKESMBKU03 are highly stable at pH 8.0 and temperature of 75 0 C. The results indicate that the endo and exocellulases produced by Humicola sp . SKESMBKU03 are more stable at high temperature and alkaline pH.

Inulin fructotransferase is an enzyme which converts inulin into difructose anhydride III (DFA III). Inulin fructrotransferase was produced by fermentation in medium containing various concentrations of inulin (10 g/L, 20 g/L) as carbon source, yeast extract (1 g/L, 2g/L) as organic nitrogen source and (NH4)2SO4 (2g/L, 5g/L) as inorganic nitrogen source using Nonomuraea sp. ID06-A0189. The aim of the study was to optimize the medium composition using various concentrations of carbon and nitrogen sources for inulin fructotransferase production by Nonomuraea sp. ID06-A0189, through shake flask system. Fermentation was conducted at 30 °C, pH 7.0 and agitated in 130 rpm for three days. The result showed that comparable with those found in another condition the highest enzyme activity was produced in medium using inulin as carbon source with concentration of 10 g/L, yeast extract as organic nitrogen source with concentration of 5 g/L and ammonium sulfate as inorganic nitrogen source with concentration of 2 g/L. Addition of inulin as a carbon source increased the volume of biomass by about 11.5-24 mL. The enzyme activity in the culture supernatant reached 25.3 U/mL after three days incubation.

The effect of organic and inorganic nitrogen sources on Trichoderma reesei Rut-C30 cellulase production was investigated in submerged cultivations. Stirred tank bioreactors and shake flasks, with and without pH control, respectively, were employed. The experimental design involved the addition of individual organic nitrogen sources (soy peptone, glutamate, glycine and alanine) within a basal medium containing Avicel (i.e. micro crystalline cellulose) and ammonium sulphate. It was found that in the shake flask experiments, the highest cellulase activities (~0.1 ± 0.02 FPU ml(-1)) were obtained with media containing soy peptone (3-6 g l(-1)) and glutamate (3.6 g l(-1)). However, these improvements in the cellulase titers in the presence of the organic nitrogen sources appeared to be related to smaller changes in the pH of the medium. This was confirmed using stirred tank bioreactors with pH control. No significant differences were observed in the highest cellulase titers and the protein pattern (according to the SDS-PAGE) of supernatants from pH controlled stirred tank bioreactor cultivations, when different nitrogen sources were used in the medium. Here the cellulase activities (~1.0 ± 0.2 FPU ml(-1)) were also much greater (8-150 times) than in shake flask cultivation. Consequently, the addition of ammonium sulphate as sole nitrogen source to Avicel basal medium is recommended when performing cultivations in stirred tank bioreactors with strict pH controlled conditions.

summaryThe growth of ten species of ectomycorrhizal fungi was measured in liquid media containing different organic and inorganic nitrogen sources. All fungi grew well on ammonium. Growth on nitrate was generally lower, although there was considerable variation between different isolates of the same species. Suillus variegatus, Piloderma croceum, Paxillus involutus, Hebeloma crustuliniforme and unidentified pink and white isolates often grew as well on organic nitrogen sources as on ammonium. Growth of the other species was more variable. Isolates of Thelephora terrestris and Lactarius rufus varied in their ability to use bovine serum albumen (BSA) but two Laccaria species were poor at using the protein as a nitrogen source. The ability of mycorrhizal and non‐mycorrhizal Pinus contorta Dougl. ex Loud, plants to utilize BSA was also examined. Non‐mycorrhizal plants and mycorrhizal plants infected with either T. terrestris or the unidentified pink ectomycorrhizal symbiont were supplied either with ammonium or with BSA. Growth of plants supplied with BSA was significantly increased by mycorrhizal infection with the pink symbiont and not significantly different from that of plants supplied with ammonium, but non‐mycorrhizal plants were unable to use the protein as a nitrogen source and had significantly lower yields and nitrogen contents than infected plants. In contrast, mycorrhizal infection with T. terrestris had no effect on growth or nitrogen contents of plants supplied with protein. The results are discussed in relation to possible physiological differences between ectomycorrhizal fungi occurring at different successional stages of forest development.

The successive outbreak of large-scale Ulva prolifera green tides in the Yellow Sea, China, from 2007 to 2017, is a serious regional environmental issue that attracts worldwide attention. The competitive advantage in nitrogen uptake and utilization is an important factor, making U. prolifera the dominant green-tide-forming seaweed. However, the detailed preference characteristics of U. prolifera for nitrogen uptake and assimilation in common inorganic and organic nitrogen sources is poorly understood and is studied using stable nitrogen isotope (15N) analysis. Our results reveal that various nitrogen sources can be simultaneously and directly taken up by U. prolifera. The uptake rates are in the sequence of NO3− (nitrate) > NH4+ (ammonium) > CO(NH2)2 (urea) > C2H5NO2 (glycine) and C3H7NO2 (alanine). In other words, U. prolifera mostly prefers inorganic nitrogen, such as nitrate and ammonium, although it can also utilize different organic nitrogen sources simultaneously. Moreover, the assimilation of NH4+ is inhibited and its uptake cannot be fitted by the Michaelis–Menten equation when the alga is exposed to multiple nitrogen sources. We propose that at the early and middle stages of green tides the rich inorganic nitrogen sources (especially NO3−) in seawater are very important to support the fast growth of U. prolifera, while at the later stage of green tides, when inorganic nitrogen sources have been exhausted, organic nitrogen sources may contribute importantly to maintaining the growth of U. prolifera, thus lengthening the duration of green tides.

Role of nitrogen sources in fermentative production of oxytetracycline by streptomyces rimosus 93060

Optimization of the submerged culture conditions for the mycelial growth and production of exopolysaccharide (EPS) from a newly isolated Cordyceps species (C. militaris NG3) was studied in flask cultures. The optimal temperature and initial pH for EPS production were 30 degrees C and 8.0, respectively. Sucrose (30 g/L) and corn steep powder (10 g/L) were the most suitable carbon and nitrogen source for both mycelial growth and EPS production. There was a distinguishable morphological changes in mycelium grown between organic and inorganic nitrogen sources. A smooth pellet growth with heavy hyphal thickness was observed in the medium containing organic nitrogen sources, whereas irregular pellets with less hairy region were formed in the medium containing inorganic nitrogen sources. More highly branched cells appearing in the medium of organic nitrogen sources seemed a favorable morphological form for both EPS production and mycelial growth. Under optimal culture conditions, the maximum concentrations of mycelial growth and EPS were 17.6 and 3.4 g/L in a 5-L stirred-tank fermenter. Four groups of EPSs (designated as Fr-I, Fr-II, Fr-III, and Fr-IV) were obtained from the culture filtrates by size exclusion chromatography (SEC), and their molecular characteristics were examined by a multiangle laser-light scattering (MALLS) and refractive index (RI) detector system. The weight-average molar masses of the Fr-I, Fr-II, Fr-III, and Fr-IV of EPS were determined to be 2.262 x 10(6), 3.348 x 10(5), 1.049 x 10(5), and 5.059 x 10(4) g/mol, respectively. All four EPSs showed very low polydispersity indices ranging from 1.00 to 1.18. The SEC/MALLS analysis revealed that the molecular shape of the Fr-I was a rigid sphere suspected to be an aggregate of complex polysaccharides, the Fr-II and Fr-III were nearly globular in shape, and the Fr-IV was an almost rodlike structure.

Influence of nitrogen source on low temperature growth of verotoxigenicEscherichia coli

The heterologous production of iso-migrastatin (iso-MGS) was successfully demonstrated in an engineered S. lividans SB11002 strain, which was derived from S. lividans K4-114, following introduction of pBS11001, which harbored the entire mgs biosynthetic gene cluster. However, under similar fermentation conditions, the iso-MGS titer in the engineered strain was significantly lower than that in the native producer - Streptomyces platensis NRRL 18993. To circumvent the problem of low iso-MGS titers and to expand the utility of this heterologous system for iso-MGS biosynthesis and engineering, systematic optimization of the fermentation medium was carried out. The effects of major components in the cultivation medium, including carbon, organic and inorganic nitrogen sources, were investigated using a single factor optimization method. As a result, sucrose and yeast extract were determined to be the best carbon and organic nitrogen sources, resulting in optimized iso-MGS production. Conversely, all other inorganic nitrogen sources evaluated produced various levels of inhibition of iso-MGS production. The final optimized R2YE production medium produced iso-MGS with a titer of 86.5 mg/L, about 3.6-fold higher than that in the original R2YE medium, and 1.5 fold higher than that found within the native S. platensis NRRL 18993 producer.

This study examined the optimization of growth conditions of Serratia marcescens isolated from a loamy soil of the Federal University Technology Minna Nigeria, for prodigiosin production. The different optimized conditions examined were extraction solvents, incubation time, pH, temperature, carbon sources, organic nitrogen sources, inorganic nitrogen sources and agitation levels. The result reveals that methanol is an ideal solvent recording absorbance of 0.69nm, which is slightly followed by ethanol and acetone with absorbance of 0.4nm and 0.3nm respectively. The bacterium produced maximum level of pigment after 36 hours of incubation (22.20µg/L), although pigment production was observed from 12 hours of incubation onwards (7.40µg/L). The pigment production declined after 36 hours of incubation. The results also revealed that pigment production by S. marcescens was maximum at 25°C (25.10µg/L) followed by 30oC (22.50µg/L). The optimal production was obtained at pH 7 (25.00mg/ml) with dextrose as optimal source of carbon (22.40mg/ml). There was no pigment production at static condition but maximum pigment production was recorded at 150 rpm (22.50µg/L). All the inorganic nitrogen sources caused a reduced biomass production. Among the organic nitrogen sources tested, yeast extract supported maximum pigment (26.75µg/L) but peptone led to a decreased pigment production (9.15µg/L) compared to other organic sources. Addition of urea did not support pigment as well as biomass production. Statistical analysis shows significant differences (p<0.05) in prodigiosin productions with different substrates, temperature and agitation levels. The study revealed that the production of prodigiosin was significantly influenced by the extraction solvents, incubation time, pH, temperature, carbon sources, organic nitrogen sources, inorganic nitrogen sources and agitation levels.