Optimal Cultivation Time Research Articles

ETIOPATHOGENETIC REASONING OF URETHRAL MICROBIOTA REHABILITATION IN PATIENTS WITH ACUTE INFECTIOUS URETHRITIS

The microbiota of the male genitourinary tract is a complex dynamic system that has not been sufficiently studied. Unlike the microbiome of the female urethral mucosa, which is constantly changing, the taxonomic composition and population level of the male urethral microbiome is more stable and independent of age. The aim of the study. To improve the results of treatment of patients with inflammatory processes of the urethra by determining the taxonomic composition, population level and microscopic indicators of the "macroorganism-microbiome" ecosystem of the microbiota of the urethra in men with acute urethritis.Material and methods. The taxonomic composition and population level of the first portion of urine of 69 sexually mature men (average age 34.8±7.14 years) with acute infectious (nonspecific) urethritis were investigated. Isolation of conditionally pathogenic bacteria was carried out by the bacteriological method using optimal nutrient media, their pH, temperature and cultivation time for each taxon. The identification of isolated pure cultures was carried out according to morphological, tinctorial, cultural, biochemical properties, as well as signs of pathogenicity and antigenic structure. To determine the mechanisms of colonization of the mucous membrane of the urethra by conditionally pathogenic microorganisms, the microecological method was used.Research results. According to the taxonomic composition and the level of microecological indicators of the "macroorganism-microbiome" ecosystem of the urethra microbiota (Margalef's species richness index, Whittaker's species diversity index, and Simpson's and Berger-Parker's species dominance indices), vulgar (common), hemolytic, and enteropathogenic Escherichia coli, coagulase-positive staphylococcus. The leading role in the formation of urethritis is played by ordinary enterobacteria - E. coli, a slightly smaller etiological role in the formation of urethritis in men belongs to S. aureus (less by 17.83%), E. coli Hly+ (less by 28.35%), enteropathogenic Escherichia coli (by 83.12%). Other microorganisms have a minimal etiological role. Conclusions. Acute urethritis in men is a polyetiological disease. Enterobacteria E. coli, E. coli Hly+, enteropathogenic Escherichia coli, K. pneumoniae, S. aureus, S. epidermidis, S. viridans are involved in the formation of the inflammatory process of the urethra. The leading causative agents of acute urethritis in men are E. coli, S. aureus, E. coli Hly+, enteropathogenic escherichia, which belong to uropathogenic escherichia.

Citizen Science and Public Perceptions under A Changing Climate: an Empirical Study in The Upper Blue Nile, Ethiopia

This paper presents a citizen science approach implemented in the Upper Blue Nile (UBN) region of Ethiopia to study the farmers’ perceptions towards adequacy of the quantity of the provided water and the fairness of the irrigation distribution system. The paper also includes preliminary Machine Learning (ML) based results on finding the optimal initial cultivation time in Ethiopia as a means to alleviate heat-induced crop losses in a warmer climate.

BACTERIAL AMYLASE PRODUCTION BY THE L-LACTIC ACID-PRODUCING STRAIN USING CASSAVA STARCH SUPPLEMENTED WITH RICE BRAN

Amylase is a crucial starch-degrading enzyme, which is commercially available, prvides benefit to starchy industry to overcome viscosity problem that caused by using high starch concentration, and to supply sugar residues. This study aimed to investigate the production of amylase by the potential optical pure L-lactic acid-producing Lactococcus sp. SUT 513 for further development of the optical pure acid fermentation process from the cheap cassava starch. Rice bran, the main byproduct in the process of rice milling, was found to provide the maximum amylase production when supplemented with 4.0 g/L (w/v) to the medium containing cassava starch (20.0 g/L, w/v), compared to the cassava medium added either the expensive nitrogen source, tryptone (5.0 g/L) and yeast extract (3.0 g/L, w/v); or the cheap alternatives, soy ptotein (8.0 g/L) or urea (2.0 g/L) combined with yeast extract (3.0 g/L). The amylase activity obtained from the developed medium was approximately 3 times higher than the original medium. This bacterium gave the highest crude amylase activity of 4.848±0.237 U/mL in the suitable medium performed in a7.5-L bioreactor with 3.0-L working volume for the optimal cultivation time of only 18 h under a control pH of 7.0, temperature at 35°C, agitation at 150 rpm, and without aeration. The results reveal the high potential production of amylase by Lactococcus sp. SUT 513 using the cheap cassava starch medium supplemented with rice bran, providing an opportunity to develop both amylase and optically pure L-lactic acid production processes.

Selection of optimal conditions for the lactic acid biosynthesis

Lactic acid is used in various industries: chemical, food, cosmetic, pharmaceutical, agriculture and polymer production. 40% of the domestic market demand for lactic acid is met through imports, while the main methods for producing lactic acid are microbiological or synthetic. The most rational is microbiological synthesis, however, when it is implemented, valuable sugar-containing substrates (crystalline sucrose, molasses, sugar syrup) are used, which significantly affects the cost of the final product. There was an obvious need to search for new technologies for the production of lactic acid. Prospective and cost-effective is the processing of whey into lactic acid using bacterial fermentation of the lactose contained in the whey. The aim of the study is to screen cultures of microorganisms capable of fermenting lactose contained in milk whey and to select the composition of the medium that provides the maximum yield of lactic acid. Strains of lactic acid bacteria were used in the experiment: Leuconostocmesenteroides subsp. mesenteroides 122 (B1699), Lactobacillus brevis B78 (B5728), Lactobacillus plantarum K9 (B5466), Lactobacillus casei C1 (B5726), Lactobacillus acidophilus (B9012), Lactobacillus paracasei BT 24/88 (B6253), Lactobacillus paracasei 139 (B2430), obtained from the Russian National Collection of Industrial Microorganisms (Scientific Center "Kurchatov Institute" -Research Institute for Genetics and Selection of Industrial Microorganisms). The authors determined the optimal composition of the medium for the biosynthesis of lactic acid by selecting the concentrations of yeast autolysate and salt solution that provide the maximum yield of lactic acid. The authors also selected the optimal duration of lactic acid biosynthesis. The study of the acid-forming ability of strains of lactic acid bacteria showed that of the strains studied, Lactobacillus casei C1 (B5726) showed the greatest ability to ferment lactose by synthesizing lactic acid, which correlates with the data on assimilation of lactose by the culture. The optimal cultivation time (132 h) and the concentration of yeast lysate (5%) in a nutrient medium based on curd whey were selected. With optimal parameters, the maximum concentration of lactic acid in the culture liquid of Lactobacillus casei C1 (B5726) was 54.77 g / L, which is comparable with the currently used producers in the industrial production of lactic acid.

Integrated proteomics and histochemical analysis of Araucaria angustifolia (Bertol.) Kuntze (Araucariaceae) in embryogenic suspension culture

t Cell suspension culture is a useful in vitro model-system for both scaling up and conserving the Brazilian conifer Araucaria angustifolia. In the present work, cell suspension of Araucaria was subjected to proteomics, biochemical and histochemical analyses. The results revealed new insights underlying the molecular mechanism of proembryogenic masses transition in cell suspension. Embryogenic cell cultures were cultivated in a basal liquid medium modified in a Steward apparatus (orbital agitator). Cell growth dynamics was evaluated using cell volume after sedimentation, fresh weight, mitotic index, conductivity, pH, and the number of proembryogenic masses (PEMs: I, II, III). Histochemical parameters, cell viability, and cell death analyses were performed to pinpoint growth rates. Proteomics analysis was performed using two-dimensional electrophoresis, and protein identification was carried out by MALDI-TOF-TOF tandem mass spectrometry. Cell growth dynamics showed a predominance of PEM III. Maximum slope of the exponential phase growth in fresh weight occurred at exponential phase after 15 days (optimal cultivation time), after which cell viability and pH decreased, thereby allowing the identification of stressrelated proteins. Several metabolism and growth proteins were abundant, such as: cytoskeletal, WOX1, cytokinin-related, and auxin-related proteins acting on cell wall modification, suspensor cell formation, and PEM I to PEM III transition.

Metabolomic Analysis of Response to Nitrogen-Limiting Conditions in Yarrowia spp.

Yarrowia is a yeast genus that has been used as a model oleaginous taxon for a wide array of studies. However, information regarding metabolite changes within Yarrowia spp. under different environmental conditions is still limited. Among various factors affecting Yarrowia metabolism, nitrogen-limiting conditions have a profound effect on the metabolic state of yeast. In this study, a time-course LC-MS/MS-based metabolome analysis of Y. lipolytica was performed to determine the optimal cultivation time and carbon-to-nitrogen ratio for studying the effects of nitrogen-limiting conditions on Yarrowia; we found that cultivation time of 36 h and carbon-to-nitrogen ratio of 4:1 and 5:0 was suitable for studying the effects of nitrogen-limiting conditions on Yarrowia and these conditions were applied to six strains of Yarrowia. These six strains of Yarrowia showed similar responses to nitrogen-limiting conditions; however, each strain had a unique metabolomic profile. Purine and pyrimidine metabolism were the most highly affected biological pathways in nitrogen-limiting conditions, indicating that these conditions affect energy availability within cells. This stress leads to a shift in cells to the utilization of a less ATP-dependent biological pathway. This information will be beneficial for the development of Yarrowia strains for further scientific and industrial applications.

Biosynthesis of pyruvic acid from glycerol-containing substrates and its regulation in the yeast Yarrowia lipolytica

The ability of different yeasts to synthesize pyruvic acid (PA) from glycerol-containing substrates has been studied. The selected strain Yarrowia lipolytica VKM Y-2378 synthesized PA with α-ketoglutaric acid (KGA) as a byproduct. The content of KGA greatly depended on cultivation conditions. The minimal formation of the byproduct was provided by the limitation of yeast growth by thiamine (0.6 µg/g biomass); the use of ammonium sulfate (0.6%) as a nitrogen source; addition of glycerol to cultivation medium in 20 g/L portions; maintaining the cultivation temperature at 28 °C, pH of the cultivation medium at 4.5, and medium aeration between 55 and 60% of saturation; the optimal cultivation time was 48 h. The selected strain cultivated under such conditions in a fermenter with a waste glycerol from biodiesel production process synthesized 41 g/L PA with a yield of 0.82 g/g. The mechanism of PA production from glycerol-containing substrates in Y. lipolytica is discussed.

Waktu Kultivasi Optimal dan Aktivitas Antibakteri dari Ekstrak Etil Asetat Jamur Simbion Aspergillus unguis (WR8) dengan Haliclona fascigera

Penelitian tentang penentuan waktu optimal pertumbuhan jamur simbion Aspergillus unguis (WR8) dan pengujian aktivitas antibakteri telah dilakukan. Kultivasi jamur dilakukan dengan menggunakan media Sabaoraud Dextrose Broth (SDB) dalam keadaan statis dan di-shaker (120 rpm) pada suhu 25-28oC. Pertumbuhan jamur secara optimal ditentukan berdasarkan jumlah biomassa kering miselia jamur per satuan waktu. Media cair diekstraksi dengan pelarut etil asetat, ekstrak etil asetat selanjutnya digunakan untuk pengujian aktivitas antibakteri menggunakan metode difusi agar terhadap bakteri Staphylococcus aureus. Hasil penelitian menunjukkan bahwa waktu optimal pertumbuhan jamur simbion tersebut dalam keadaan statis adalah pada hari ke-21 dan diameter hambat ekstrak (5 %b/v) adalah 21 mm. Sedangkan waktu optimal pertumbuhan jamur yang di shaker adalah pada hari ke-14 dan diameter hambat ekstrak sebesar 11 mm. Dapat disimpulkan waktu kultivasi optimal untuk menghasilkan senyawa antibakteri dari jamur A. unguis (WR8) adalah selama 21 hari secara statis menggunakan media cair.

Optimal Cultivation Time for Yeast and Lactic Acid Bacteria in Fermented Milk and Effects of Fermented Soybean Meal on Rumen Degradability Using Nylon Bag Technique.

The objectives of this study were to determine an optimal cultivation time for populations of yeast and lactic acid bacteria (LAB) co-cultured in fermented milk and effects of soybean meal fermented milk (SBMFM) supplementation on rumen degradability in beef cattle using nylon bag technique. The study on an optimal cultivation time for yeast and LAB growth in fermented milk was determined at 0, 4, 8, 24, 48, 72, and 96 h post-cultivation. After fermenting for 4 days, an optimal cultivation time of yeast and LAB in fermented milk was selected and used for making the SBMFM product to study nylon bag technique. Two ruminal fistulated beef cattle (410±10 kg) were used to study on the effect of SBMFM supplementation (0%, 3%, and 5% of total concentrate substrate) on rumen degradability using in situ method at incubation times of 0, 2, 4, 6, 12, 24, 48, and 72 h according to a Completely randomized design. The results revealed that the highest yeast and LAB population culture in fermented milk was found at 72 h-post cultivation. From in situ study, the soluble fractions at time zero (a), potential degradability (a+b) and effective degradability of dry matter (EDDM) linearly (p<0.01) increased with the increasing supplemental levels and the highest was in the 5% SBMFM supplemented group. However, there was no effect of SBMFM supplement on insoluble degradability fractions (b) and rate of degradation (c). In conclusion, the optimal fermented time for fermented milk with yeast and LAB was at 72 h-post cultivation and supplementation of SBMFM at 5% of total concentrate substrate could improve rumen degradability of beef cattle. However, further research on effect of SBMFM on rumen ecology and production performance in meat and milk should be conducted using in vivo both digestion and feeding trials.

Study on Hydrolysis Conditions of &lt;i&gt;Lactobacillus bulgaricus&lt;/i&gt; on Casein Sodium by Method of Response Surface and the Antioxidant Activity of Hydrolysates

In order to study the ability ofLactobacillus bulgaricushydrolyzed protein, using casein sodium as substrate, the content of free amino acid and relative ORAC value were used as the index optimization. The conditions including: hydrolysis temperature, cultivation time,Lactobacillus bulgaricusdosage and pH values were investigated by single-factor experiment. In this paper we studied the hydrolysis conditions ofLactobacillus bulgaricuson casein sodium by the Box-Behnken response surface and the optimal hydrolysis temperature, cultivation time,Lactobacillus bulgaricusdosage and pH value were determined to be 43 °C, 36 h, 25 OD/ml, and pH 6.6, respectively. The optimum value of response surface is 857.75 mg/l. In addition, the analysis of relative ORAC value of response surface showed that there is no direct relationship between the degree of protein hydrolysis and radical scavenging activity, namely as extensive hydrolysis could have a negative impact on the antioxidant activity.

Effects of various LED light qualities and light intensity supply strategies on purification of slurry from anaerobic digestion process by Chlorella vulgaris

The slurry from anaerobic digestion process (biogas slurry) is now well known to potentially cause water eutrophication and even large-scale algal blooms. The Chlorella vulgaris utilized in this research is able to purify the biogas slurry effectively under optimum light quality and light intensity supply strategy. The descending order of dry cell weight for C. vulgaris reproduction and nutrient removal efficiency of biogas slurry both are red > white > yellow > purple > blue > green, indicating that the red light is the optimum light quality. Furthermore, this study was among the first attempt to analyzed the economic efficiency for nutrient removal under various light intensity supply strategies, and found out that the optimal light intensity supply strategy used for microalgae culture should be incremental intensity strategy, rather than constant intensity strategy, to avoid light energy wastage and photoinhibition. The optimal light intensity supply strategy is: Phase 1, 0–48 h with 800 μmol m−2 s−1; Phase 2, 48–96 h with 1200 μmol m−2 s−1; and Phase 3, 96–144 h with 1600 μmol m−2 s−1. In addition, the optimal cultivation time is 144 h.

Effects of various LED light wavelengths and light intensity supply strategies on synthetic high-strength wastewater purification by Chlorella vulgaris

Chemical fertilizer agricultural wastewater is a typical high-strength wastewater that has dramatically triggered numerous environmental problems in China. The Chlorella vulgaris microalgae biological wastewater treatment system used in this study can effectively decontaminate the high-strength carbon and nitrogen wastewater under an optimum light wavelength and light intensity supply strategy. The descending order of both the dry weight for C. vulgaris reproduction and wastewater nutrient removal efficiency is red>white>yellow>purple>blue>green, which indicates that red light is the optimum light wavelength. Furthermore, rather than constant light, optimal light intensity is used for the incremental light intensity strategy. The phases for the optimal light intensity supply strategy are as follows: Phase 1 from 0 to 48h at 800μmolm(-2)s(-1); Phase 2 from 48 to 96h at 1,200μmolm(-2)s(-1); and Phase 3 from 96 to 144h at 1,600μmolm(-2)s(-1). Additionally, the optimal cultivation time is 144h.

Effects of various LED light wavelengths and intensities on the performance of purifying synthetic domestic sewage by microalgae at different influent C/N ratios

In Chinese rural areas, domestic sewage is one of the main sources of water pollution that may cause water eutrophication if directly discharged into natural waters without appropriate treatment. This study demonstrates that the microalgae Chlorella vulgaris can effectively remove nutrients from domestic sewage. In this process, red is the optimal light wavelength, with an intensity strategy as follows: Phase 1, 0–48h with 1000μmolm−2s−1; Phase 2, 48–96h with 1500μmolm−2s−1; Phase 3, 96–120h with 2000μmolm−2s−1; and Phase 4, 120–144h with 2500μmolm−2s−1. The optimal cultivation time was 144h. Nutrient removal efficiency was significantly affected by the light wavelength, light intensity, the effect of the interaction between light wavelength and intensity, as well as the effect of the interaction among light wavelength, light intensity, and influent C/N ratio. Moreover, the total nitrogen and total phosphorus removal efficiencies were significantly affected by the influent C/N ratio. In this study, the optimal influent C/N ratio is 5:1.

BACTERIAL EXPRESSION OPTIMISATION OF ANTITUMOR CYTOKINE EMAP II IN ESCHERICHIA COLI BL21(DE3) PLYSE CELLS

EMAP II (Endothelial Monocyte-Activating Polypeptide) – a new antiangiogenic proinflammatory cytokine that exhibits antitumor activity. In order to develop genetically engineered technology for EMAP II optimization of bacterial expression conditions within pET30a vector encoded EMAP II was carried out. Both the influence of target protein synthesis inductor IPTG concentration on its overall yield and optimal bacterial cultivation time before and after inductor addition were estimated. There was a proposed scheme for the cultivation of culture E. colі BL21(DE3)pLysE to achieve high yield of recombinant cytokine EMAP II at the level of 110 mg from 1 liter of bacterial culture.

Strain improvement of Serratia marcescens ECU1010 and medium cost reduction for economic production of lipase

Industrial strain improvement plays a central role in the commercial development of microbial fermentation processes. The strain of Serratia marcescens ECU1010, a wild-type lipase-producer capable of stereospecific synthesis of a Diltiazem precursor, was subjected to physical mutation involving treatment by UV-irradiation for 30 s. A mutant strain, no. UV-01, showed enhanced lipase production, but lost the capability of producing red pigment (prodigiosin). The variant strain UV-01 had a 2.3-fold higher activity than the wild type and was stable in its enzyme production for ten serial transfers. For reduction of the fermentation medium cost, dried powder of corn steep liquor was used as an inexpensive substitute for beef extract in the medium. Dextrin as an organic carbon source and Tween-80 as an important element were further optimized, respectively. The high primary biodegradation of the Tween-80 by S. marcescens ECU1010 and its variant demonstrated their potential ability of degrading alkyl polyethoxylates to remove harmful nonionic surfactants from polluted effluents and streams. The optimal cultivation time for lipase biosynthesis was 24 h. These optimized compositions resulted in an economic production of lipase by S. marcescens ECU1010 var. UV-01, with a dramatically reduced cost (1/8–1/7 of the initial one) which is more suitable for industrial application.

Seasonal Phytochemical Variation of Anti-Glycation Principles in Lowbush Blueberry (Vaccinium angustifolium)

Diabetic hyperglycaemia promotes the production of advanced glycation end-products (AGEs), which play a significant role in the development of complications associated with type 2 diabetes mellitus. Vaccinium angustifolium, a medicinal plant used for the treatment of diabetes, produces a variety of phenolic metabolites with putative anti-diabetic activities. To assess optimal cultivation time, seasonal changes in the concentration of six phenolic compounds in leaves and twelve compounds in stems were examined using HPLC-DAD and examined in relation to seasonal changes in AGE inhibition activity, assessed with a fluorescence-based assay. A seasonal decline occurred in the concentration of chlorogenic acid, rutin, and quercetin 3-arabinoside in leaves and chlorogenic acid in stems. The concentration of (+)-catechin, and (-)-epicatechin in stems declined within two weeks before rising and fluctuating insignificantly. AGE inhibition activity of leaves was significantly greater at the final compared to the initial collection date whereas the activity of stems did not change significantly. Relative to the leaf extract, the stem was a more potent inhibitor of AGE formation, which could be a result of the unique phytochemistry of stems. Together, these results revealed significant seasonal variation in the phenolic profile and anti-glycation effects of V. angustifolium extracts and indicated late summer as the collection time yielding optimal activity.

Removal of heavy metals from aqueous solutions using bacteria

The accumulation of heavy metals by microbial biomass with high surface area-to-volume ratio holds great potential for heavy metal removal in both soluble and paritcular forms, especially when the heavy metal concentrations are low (<50 mg/L). E. coli and B. subtilis are effective agents for metal removal. We further investigated the effect of pH, temperature, equilibration time, and pre-treatment reagents on the removal of Pb(II), Cd(II) and Cr(VI) from aqueous solutions by E. coli and B. subtilis. E. coli and B. subtilis were cultivated for 60 hours, the experimentally determined optimal cultivation time before they were used in metal removal experiments. Under the optimal conditions of pH 6.0, equilibration temperature 30 C and equilibration time 1 hour, 63.39% and 69.90% Cd(II) can be removed by E. coli and B. subtilis. Under the optimal conditions of pH 5.5, equilibration temperature 30 C and equilibration time 1 hour, 68.51% and 67.36% Pb(II) can be removed by E. coli and B. subtilis. And under the optimal conditions of pH 5. 5, equilibration temperature 30 C, and equilibration time 1 hour, 60.26 % and 54.56 % Cr(W) can be removed by E. coli and B. subtilis. Chemical treatment of cultivated bacteria (0.1 mol/L NaOH, 0.1 mol/L HC1, 30% ethanol, and distilled water) affects the efficiency of metal removal by E. coli and B. subtilis. Pretreatment of biomass by NaOH enhanced Cd(II), Pb(II) and Cr(VI) removal, while pretreatment by HC1, ethanol and distilled water reduced Cd(II), Pb(I) and Cr(YI) removal. For metal removal from industrial waste discharges, pretreated biomass of E. coli can remove 68.5% of Cd and 58.1% of Cr from solutions, while pretreated biomass of B. subtilis can remove 62.6% of Cd and 57% of Cr from solutions.

Preconcentration of trace copper with yeast for river water analysis

A new preconcentration method with yeast is presented. The method was evaluated for the determination of trace copper in river water by graphite furnace atomic absorption spectrometry (GFAAS). A suitable cultivation bed for preconcentration of copper was 3.5 mg ml −1 2-ammonium hydrogen phosphate. The optimal cultivation time and temperature were 2 h and 40°C. Under optimal conditions, copper in aqueous sample was concentrated about seven-fold by yeast. The detection limit was 85 pg ml −1 (3S/N) for copper in river waters. The yeast preconcentration method was applied to the determination of copper in river waters. The recovery of spiked copper was in the range of 93–100%. By the preconcentration, it was found that ultra trace copper in river waters could be determined without interferences of matrix elements, after only the cultivation and no chemical treatment.

Submerged cultivation of a strain ofHumicola lutea 72 producing acid protease

It is demonstrated for the first time that a species from the genusHumicola is a potential source of acid protease. A strain was classified by morphological investigations asHumicola lutea. The influence of constituents of the culture medium on the growth and acid protease production ofH. lutea 72 in submerged cultivation in flasks was investigated. An improved medium was devised for future studies. The optimal aeration rate, inoculum level and cultivation time were determined. A maximal proteolytic activity of 670 μg tyrosine liberated from casein ml−1 culture filtrate min−1 at pH 3.0 was obtained.

STUDY OF THE CONDITIONS OF RIBOSIDATION OF 6-AZAURACIL.

When studying the optimal conditions for the ribosidation of 6-azauracil it was found that the optimal cultivation time for the strainEscherichia coli 556 was 6–8 hours. Prolongation of the cultivation time slowed down the rate of ribosidation. On using 3-hour cells concentrated to the optimal extinction value 0.95 (corresponding to a 6-hour culture), ribosidation of 6-azauracil was only 50%. Either D-ribose itself or a saccharide capable of transformation in the presence of 6-azauracil, i.e. a saccharide which can be transformed by the enzyme system of the microorganism into D-ribose, should be used as the precursor of the riboside chain in the transformation of D-azauracil.