Substrate pH Research Articles

Study on Methanol Production with Vegetable in Rotating Reactor

Fuel methanol is on demand nowadays. Lignocelluloses and algal biomasses are largely generated as waste materials out of agricultural practises and process industries. In the present work, methanol production by Saccharomyces cerevisiae was carried out using lignocellulosic biomass (vegetable) as a substrate and using rotating biological reactor that utilizes biologically pretreated vegetable as substrates for methanol production and its process optimization. During the batch experiment with varying substrate concentration (60-100 g/l), pH (4.8-5.8) and commercial cellulase enzyme concentration of (10- 20 mg/ml) resulted in 38.9 g/l of methanol concentration with a maximum of 17 % yield. The SEM analysis was carried out for analysing the structural morphology of the untreated, pretreated, hydrolysed and fermented samples.

Development of engineered Escherichia coli whole-cell biocatalysts for high-level conversion of L-lysine into cadaverine.

A whole-cell biocatalytic system for the production of cadaverine from L-lysine has been developed. Among the investigated lysine decarboxylases from different microorganisms, Escherichia coli LdcC showed the best performance on cadaverine synthesis when E. coli XL1-Blue was used as the host strain. Six different strains of E. coli expressing E. coli LdcC were investigated and recombinant E. coli XL1-Blue, BL21(DE3) and W were chosen for further investigation since they showed higher conversion yield of lysine into cadaverine. The effects of substrate pH, substrate concentrations, buffering conditions, and biocatalyst concentrations have been investigated. Finally, recombinant E. coli XL1-Blue concentrated to an OD(600) of 50, converted 192.6 g/L (1317 mM) of crude lysine solution, obtained from an actual lysine manufacturing process, to 133.7 g/L (1308 mM) of cadaverine with a molar yield of 99.90 %. The whole-cell biocatalytic system described herein is expected to be applicable to the development of industrial bionylon production process.

Optimum N and P rates for greenhouse production of vegetative coleus using constant liquid feed

ABSTRACTMany new coleus (C. hybridus cv.) cultivars are vegetatively propagated and require different fertilization practices from seed propagated cultivars. Two experiments were conducted to evaluate growth responses of Henna, Indian Summer, Mint Mocha, New Orleans Red, Red Head, and Trusty Rusty to 0, 70, 140, 280 and 420 mg·L−1 nitrogen (N), and Henna, Mint Mocha, Red Head, and Trusty Rusty to 0, 6.2, 12.4, 24.8, or 49.6 mg·L−1 phosphorus (P) to determine optimum constant liquid feed rates to produce marketable size plants from rooted cuttings. Positive growth responses in terms of biomass were found with increasing N rates but not P rates. For medium-sized cultivars such as Henna, Indian Summer, and New Orleans Red, quadratic responses were found in aboveground biomass, and N at 280 mg·L−1 resulted in similar plant size and dry weight as those fertilized at 140 and 420 mg·L−1 N. For large-sized cultivars such as Mint Mocha, Red Head and Trusty Rusty, plant dry weight responded linearly within the N range tested and were greatest at 420 mg·L−1. However, plant visual quality was negatively affected by N rates at 280 and 420 mg·L−1 in that, leaf color became less intense at these high N rates. Plants fertilized at 70 mg·L−1 were smaller than those fertilized at 140 mg·L−1, however, they received similar visual quality ratings because of more intense leaf color. Therefore, N at 70 to 140 mg·L−1 can be used to grow most vegetative coleus for similar marketable quality. Mint Mocha and Henna were the only cultivars responded to P treatments that, 12.4 mg·L−1 P rate resulted in greater biomass than the no-P control. All other cultivars had no response to supplemental P except a linear response in tissue P%. Therefore, supplemental P is not required during the 8 week production period when there is an initial P charge in the substrate. We found that substrate pH decreases with higher P rates, therefore supplemental P fertilizer can be used for adjusting pH. Both N and P rates found optimum in this study are lower than current industry practices (N at 150 to 250 mg·L−1 and P at 24 mg·L−1) and can significantly lower production cost and potential leaching of excessive nutrient into waterway. Nutrient treatments in further study on postharvest performance of vegetative coleus will be selected based on this study.

Substrate pH Impacts Efficacy of Ethephon Drenches on Growth of Herbaceous Perennials

Ethephon [(2-chloroethyl) phosphonic acid] is widely used as a growth regulator in floricultural crop production, with foliar sprays as the typical application method. Ethephon efficacy is determined by rate of uptake and subsequent ethylene evolution, which can be influenced by a number of factors, including solution pH. This study examines whether an ethephon substrate drench (100 mg⋅L−1 at a volume of 296 mL per 2.8-L container) would allow for plant uptake in two herbaceous perennials, Verbena bonariensis (L.) ‘Lollipop’ and Veronica spicata (L.) ‘Goodness Grows’, as measured by subsequent effects on shoot growth and days to flower. We also investigated substrate pH effects on ethephon drench efficacy by analyzing the shoot responses to ethephon applied at a range of starting substrate pH (4.5 to 7.0) compared with untreated plants grown under the same substrate pH conditions (controls). One or more measurements of shoot growth (height, width, shoot dry weight) were reduced in both taxa treated with ethephon as compared with controls. Veronica plant growth was not influenced by substrate pH in either the control or ethephon-drenched plants. For Verbena plants receiving the ethephon drench, as substrate pH increased, height and width increased. For example, when ethephon was applied at substrate pH 4.5, finished plant height averaged 32.0 cm, compared with 43.5 cm for those plants that received the drench at a substrate pH of 7.0. Increasing substrate pH conditions also influenced the days to flower in Verbena plants. Ethephon-treated plants at a substrate pH of 4.5 required an average of 6.5 days longer to flower than those at a substrate pH of 7.0. In summary, ethephon drench applications can result in significant growth regulation effects, as seen in both Veronica and Verbena. Furthermore, increasing substrate pH can reduce the efficacy of ethephon drench applications.

X-ray Photochemistry of Prussian Blue Cellulosic Materials: Evidence for a Substrate-Mediated Redox Process.

Beside its promising applications in the design of multifunctional materials, batteries and biosensors, the pigment Prussian blue is still studied in heritage science because of its capricious fading behavior due to a complex light-induced redox mechanism. We studied model heritage materials composed of Prussian blue embedded into a cellulosic fiber substrate by means of X-ray absorption near-edge spectroscopy. Significant X-ray radiation damage was observed and characterized. X-ray radiation induced first a reduction of Prussian blue, in a similar way to what visible light does, followed by a complete degradation of the pigment and the formation of iron(III) oxyhydroxide. We took advantage of this X-ray photochemistry to investigate in depth the redox behavior of Prussian blue. We could particularly demonstrate that the rate, extent, and quality of Prussian blue photoreduction can be tuned by modifying the pH and alkali cation content of the cellulosic substrate. The present study represents a step further in the understanding of Prussian blue heritage materials from an electrochemical viewpoint and provides evidence of substrate-mediated photochemistry applicable to a wider class of Prussian blue composite materials.

Alleviating the toxicity of heavy metals by combined amendments in cultivated bag of Pleurotus cornucopiae.

The substrate of mushroom can be polluted with heavy metals and subsequently contaminate mushroom, which requires alternative solutions to reduce associated environmental and human health risks. The effects of amendment application on alleviating Cu and Cd toxicities to Pleurotus cornucopiae were investigated in a cultivated bag experiment conducted with the naturally contaminated substrate. Addition of combined amendments (sodium bentonite, silicon fertilizer, activated carbon, and potassium dihydrogen phosphate) increased the P. cornucopiae biomass and substrate pH. Cu and Cd concentration in P. cornucopiae as well as the available Cu and Cd in substrate reduced for the presence of amendments, and the silicon fertilizer had the biggest inhibition on metal uptake. The smallest amount of Cu and Cd in P. cornucopiae was only 30.8 and 5.51% of control, respectively. Moreover, application of amendments also decreased malondialdehyde (MDA) and hydrogen peroxide (H2O2) level in metal-stressed mushroom by 4.38-53.74 and 8.90-58.42% relative to control, respectively. The decreased oxidative stress could well contribute to the growth of P. cornucopiae, and the elevated substrate pH might lead to the lower metal availability, thus resulting in the reduction of metal accumulation in mushroom. These above results suggest that application of combined amendments in mushroom substrate could be implemented in a general scheme aiming at controlling metal content in P. cornucopiae.

Investigation of a structure of new functional peptide composite materials with gold nanoparticles

A structure of new composite coatings formed at room temperature from dispersions of gold nanoparticles (NPs) in an aqueous solution of a peptide (PT) Asp-Glu-Val-Asp-Trp-Phe-Asp on mica, glass, silicon, aluminum, and gold substrates was investigated by IR spectroscopy, microprobe and laser interference microscopy, and dynamic light scattering. The size of gold NPs in the solution is 40 nm. It has been established that an individual PT crystallizes, forming various structures, the character of which significantly depends on the substrate nature, surface conditions, and pH value of the medium. At pH ∼ 9, a zwitterionic state of the PT molecule breaks down and its isomeric form changes (from trans-to cis-configuration). As a result, the forming peptide layer becomes disordered and the layer growth mechanism changes from lateral to a normal one. Globular and fibrillar structures form in the composite layers adjacent to the substrate, and peptide layers with complicated morphology (dendrites and spherulites) grow above them. The shapes and sizes of gold NPs in the coatings and differences in the structure of PT composite coatings formed with gold and silver NPs have been discussed. The conclusion has been drawn that crystallization of NPs and nanocomposite coatings can be controlled by changing the electric charge of the peptide molecule.

Substrate pH and Butterfly Bush Response to Dolomitic Lime or Steel Slag Amendment

Steel slag (SS) is a fertilizer amendment with a high concentration of calcium oxide, and thus capable of raising substrate pH similar to dolomitic lime (DL). Steel slag, however, contains higher concentrations of some nutrients, such as iron, manganese, and silicon, compared to DL. The objective of this research was to determine the effect of SS rate on pH in a substrate composed of 80 pine bark:20 sphagnum peatmoss (v:v), as well as growth and nutrient concentration of butterfly bush (Buddleja davidii ‘Pink Delight’ Franch.). The base substrate was amended with either DL or SS at rates of 0, 0.6, 2.4, 4.8, 9.5, or 14.3 kg·m−3. Substrates were placed into 12-L nursery containers and potted with a single butterfly bush per container. Dolomitic lime amendment resulted in higher substrate pH at rates from 0.6 to 4.8 kg·m−3 while the SS amendment caused a greater increase in pH at rates higher than 4.8 kg·m−3. Butterfly bush responded well to all but the highest SS rate applied. As the rate of SS increased to 14.3 kg·m−3, decreased Mg availability may have reduced shoot growth. Based on the results of this experiment, SS could be used as an alternative to DL. However, incorporation rates would need to be adjusted slightly higher for SS compared to DL to achieve a desired pH in the range of 6 to 6.5.

Unstructured kinetic model of batch fermentation of USP glycerol for lactic acid production

This study show the capability of Lactobacillus rhamnosus ATCC 7469 to produce lactic acid using crude glycerol from biodiesel production as carbon source; in addition, a kinetic model that describes the behaviour of the fermentation process using USP glycerol as substrate was proposed and developed. The strain was adapted to the new carbon source by doing successive cultures, the substrate conversion was up to 94.5% after 24 hours of fermentation using crude glycerol as under initial conditions of substrate concentration (crude glycerol) and pH of 8 g/L and 6.5, respectively. Then, the influence of initial pH (pHo) and concentration of substrate (So) were evaluated by fermentation tests of USP glycerol. The optimal value of volumetric lactic acid productivity (Qv) achieved from this study was 0.087 g·L-1·h-1 for initial pHo = 6.5 and initial substrate concentration So = 6 g/L. Lastly, the kinetics parameters of an unstructured and not segregated model (Aiba type equation for growth rate expression), were adjusted with an average fit degree of 88% for all the initial conditions, using USP glycerol. In addition, the kinetic parameters are laid out as function of initial pH and substrate concentration.

Nutrient Leaching from Container-Grown Ornamental Tree Production

Economical production of marketable container-grown ornamental shade trees with minimum amounts of nutrients in leachate requires careful management of fertilizer applications during a growing season. Sixteen fertilizer treatments were evaluated for their nutrient leaching potential in container-grown ‘Red Sunset’ red maple (Acer rubrum L.) production in a commercial nursery. Tests were conducted at two sites that were irrigated with either city or recycled pond water. Two slow-release granular fertilizers (18-5-12 and 12-0-42) were applied separately or together, by incorporation, top-dressed, or both, to trees grown in #7 containers and placed above or below ground. Trees irrigated with pond water also received supplemental liquid nutrients throughout the growing season along with nitric and phosphoric acids. Compared to either top-dressed or incorporation of fertilizer, incorporation of fertilizer combined with top-dressing doubled the amounts of nutrients applied but did not increase tree growth and caused greater nutrient leaching through the container substrate. Adding nitric and phosphoric acids to the supplemental liquid nutrients had little effect on lowering pH of the container substrate to the desired level. Trees irrigated with pond water had greater caliper growth than trees irrigated with city water, but this practice caused greater nutrient loss through the leachate and required additional nutrient inputs and labor throughout the growing season. Among the 16 fertilizer practices, the top-dressed fertilizer applications in the above- and below-ground containers were the most efficient method to produce fast tree growth with low nutrient leaching.

Influence of substrate pH on the growth and flowering of Mandevilla Lindl. Sundaville® ‘Pretty Red’

Abstract Sundaville is the brand name of a new collection of cultivars of the genus Mandevilla (syn. Dipladenia), with the potential to become a leading vine in the world horticultural market. The research was carried out in order to analyse the growth of Sundaville ‘Pretty Red’ at different values of substrate pH (4.0, 4.7, 5.3 and 5.5). The study shows that flowers appeared after more than six months irrespective of soil conditions. Plants cultivated at pH 4.0 had the longest leaves, but at the highest substrate pH the widest leaf laminae were observed. Regardless of the substrate pH, the diameter of a single flower remained the same. Plants cultivated at a pH lower than 5.0 produced more flower buds and more flowers in comparison with the plants exposed to the higher pH. Moreover, pH < 5.0 positively affected the number of stems. The soil pH did not only affect the growth, but also the health of the plants. The lowest pH level (4.0) caused adverse changes to the leaves.

Caracterização física e química de substratos com diferentes proporções de resíduo de celulose

The objective of this study was to characterize physic and chemically substrates with different proportions of cellulose residue. The components of substrate used were soil, sand and cellulose residue and the treatments were: T1 = cellulose residue (CR); T2 = CR + soil (1:1); T3 = CR + soil (1:2); T4 = CR + soil (1:3); T5 = CR + sand (1:1); T6 = CR + sand (1:2); T7 = CR + sand (1:3); T8 = CR + soil + sand (1:1:1); T9 = CR + soil + sand (1:2:1); T10 = CR + soil + sand (1:3:1); T11 = CR + soil + sand (1:1:2); T12 = CR + soil + sand (1:1:3). It was evaluated the substrate density, container capacity, pH and electrical conductivity. The pure cellulose residue adapts in respect of physical properties. In relation to electrical conductivity the best results were obtained by mixing cellulose residue with soil and sand. The pH determined in water was high in all substrates.

Modeling the red pigment production by Monascus purpureus MTCC 369 by Artificial Neural Network using rice water based medium

Abstract The study investigates the application of Artificial Neural Network (ANN) in modeling a Liquid State Fermentation (LSF) for red pigment production by Monascus purpureus MTCC 369. A neural network model was characterized by the three fermentation parameters as neurons in the input layer and pigment yield as one neuron in the output layer. The input neurons included incubation period of 6–18 days, pH of rice water as substrate (3.0–5.0) and concentration of ammonium nitrate as nitrogen source (0.0–2.0%). The model was trained and validated to predict the red pigment yield (abs 500 nm /mg dry fungal biomass). The results showed a good fit between predicted and experimental values for the model. The maximum red pigment yield (20.44 U abs 500 nm /mg dfb) was obtained with substrate pH of 4.0 without any ammonium nitrate as N-source after 12 days of incubation. The developed ANN model can be used to predict the effects of fermentation parameters on red pigment production with a high correlation.

Steel Slag Raises pH of Greenhouse Substrates

Dolomitic lime (DL) is the primary liming agent used for increasing pH in peatmoss-based substrates. Steel slag (SS) is a byproduct of the steel manufacturing industry that has been used to elevate field soil pH. The objective of this research was to determine the pH response of a peatmoss-based greenhouse substrate to varying rates of DL or SS. Two experiments were conducted with an 85 peatmoss : 15 perlite substrate. In the first experiment, the substrate was amended with 0, 2.4, 4.8, or 7.1 kg·m−3 of either DL or SS. Half of the containers remained fallow and the other half were potted with a single sunflower (Helianthus annuus L. ‘Pacino Gold’). In the second experiment, fallow containers were only used with the substrate amended with 0, 2.4, 4.8, 9.5, or 14.2 kg·m−3 DL or SS. Sunflower were measured for relative foliar chlorophyll content, shoot mass, root ratings, and foliar nutrient concentrations. Substrate electrical conductivity (EC) and pH were measured weekly using the pour-through procedure. All sunflower plants grew vigorously, although nonamended controls had less shoot dry weight than those amended with DL or SS. There were minor differences in foliar concentration of N, Ca, Mg, and Mn; however, these differences did not adversely affect plant growth. Summarizing across both experiments, EC was affected by treatment and time, although all substrates had EC readings within the range recommended for floriculture crop production (1.0–4.6 mS⋅cm−1). Substrate pH differed slightly in Expt. 1 between fallow and planted containers. Substrate pH increased exponentially with increasing rates of either DL or SS. Maximum pH in fallow DL and SS amended substrates was 6.57 and 6.93, respectively, in Expt. 1 and 6.85 and 7.67, respectively, in Expt. 2. The SS used in this experiment resulted in a greater pH response than DL with higher application rates. SS is a viable material for raising pH of soilless substrates.

Physical Characteristics of and Seed Germination in Commercial Green Roof Substrates

Green roofs provide multiple environmental and economic benefits, such as roof surface temperature reduction, reduced internal cooling needs, storm water management, and extended life span of roofing materials. However, green roof substrates must be relatively lightweight, so it is typically coarse with limited water holding capacity. We hypothesize the physical characteristics that make the substrates successful on a roof are likely to reduce seed germination. For this study, we tested the germination of three perennial species and one annual: shasta daisy (Leucanthemum ×superbum), yarrow (Achillea millefolium), and indian blanket (Gaillardia pulchella), and pinto bean (Phaseolus vulgaris) (as a control) across five different substrates: peat/perlite/large expanded shale, compost/sand/expanded shale, compost/black dirt/expanded shale, compost/expanded shale, and peat/perlite (control). Substrate physical and chemical properties were analyzed, and a germination test conducted using a randomized complete block design, with each species/substrate combination appearing once per block. Germination was defined as seedling emergence, and monitored every 7 days for 28 days. Pinto bean had the highest germination (76.2%) across all substrates, compared with 43.4% for indian blanket, 40.4% for yarrow, and 23.0% for shasta daisy. Seed germination, across all species, was lower in green roof substrates. Germination success was very strongly correlated with seed length, seed width, and seed area, while no relationship was found between seed germination and substrate pH or electrical conductivity (EC). Therefore, it is likely that the physical characteristics of green roof substrates create poor conditions for seed germination.

표고 신품종 풍년고의 배양 특성

본 연구에서는 KFRI 490의 이핵 균사와 KFRI 536의 일핵 균사를 Di-mon 교잡을 시도하여 새로운 품종을 개발하였다. 품종명을 풍년고라 명명하였고, 생리적 특성을 파악하고자 하였다. 풍년고의 최적 균사 생장 온도는 <TEX>$25^{\circ}C$</TEX>이었고, 균사 밀도는 성김이었으며, 균총 색깔은 무색이고 피막은 형성되지 않았다. 배양 7일째 풍년고가 56.6 mm로 산림4의 52.9 mm보다 cellulase 활성이 높았고, 배양 5일째 laccase 활성 또한 풍년고 58.0 mm로 산림4호의 55.6 mm보다 높았다. 톱밥배지의 배양 전 pH는 4.7~5.5였고, 120일 배양이 완료되고 발생 직전의 pH는 3.7~3.9로 낮아졌다. 톱밥 배지의 <TEX>$CO_2$</TEX> 변화는 60일 배양에서 가장 컸으며, 봉지 안의 배지 <TEX>$CO_2$</TEX> 농도는 3.90~4.67%이었다. In this study, a new cultivar of Lentinula edodes was bred from dikaryotic KFRI 490 and monokaryotic KFRI 536 by Di-mon method. The new breed was named "Poongnyunko" and physiological characteristics was investigated. Its optimal growing temperature was <TEX>$25^{\circ}C$</TEX>, and it had thin density. Its colony was colorless and did not form any epithelium. On the <TEX>$7^{th}$</TEX> day of mycelial growth, "Poongnyunko" was 56.6 mm, and showed higher cellulase activity compared with "Sanlim 4-ho"(52.9 mm). On the <TEX>$5^{th}$</TEX> day of mycelial growth, "Poongnyunko" was 58.0 mm, and showed higher laccase activity compared with "Sanlim 4-ho" (55.6 mm). Its pH at a substrate was 6.0. Before cultivation, the pH of sawdust substrate was 4.7-5.5 went down to 3.7-3.9 after 120-day cultivation. After 60 days of cultivation, the change of <TEX>$CO_2$</TEX> was the greatest. During the cultivation, <TEX>$CO_2$</TEX> concentration in a growing bag was 4.67% to 3.90%.

A modified titrimetric method for measuring the activity of wheat germ lipase

Wheat germ lipase is a cereal lipase which plays an important role in the growth and storage of wheat products. The commonly used titrimetry is not reliable and accurate enough to determine lipase activity due to its difficulties in identifying the end point when used to measure the alkaline lipase of low activity. In this paper, acidic titration method was utilised, with triacetin as substrate to measure the activity of wheat germ lipase by an automatic potentiometric titrator. The optimum catalysis time is 4 h, the pH value of end point is 6.0, and the initial pH of substrate is 7.7. Under optimum test conditions, the activity of wheat germ lipase was found to be 50.398±0.848 U/mg, within a linear range of 1.0-10.0 mg, and with relative standard deviation equal to 1.682%. This method has proved to be precise and reproducible for measuring alkaline lipase of low activity in aqueous solution.

Ethanol Production from Cashew Apple Juice Using Immobilized Saccharomyces cerevisiae Cells on Silica Gel Matrix Synthesized from Sugarcane Leaf Ash

Ethanol is considered to be a promising alternative fuel to meet ever growing energy demands. In the present work, immobilized yeast cells by Saccharomyces cerevisiae were used for ethanol production from cashew apple juice as the substrate. The support, silica gel, was derived from a novel precursor sugarcane leaf ash. Sugarcane leaf is chosen due to its abundant availability, low cost, and also as a means to remove the agricultural residue. Substrate concentration, pH, and temperature have been optimized to achieve maximum production of ethanol. Maximum ethanol production was obtained at a substrate concentration of 70% (v/v), pH 6 and a temperature of 30°C. Maximum ethanol production was found to be 16,200 mg/L. Ethanol purity was determined and was found to be 97.79% pure (water free). Continuous ethanol fermentation was carried out in a packed bed reactor.

Sensitivity of Fomes annosus Fr. Cooke and Schizophyllum commune Fr. to air pollution with sulphur dioxide

The sensivity of mycelium to sulphur dioxide polluting the air depends on its physiological activity. As measure of activity growth was adopted, in the sense of the function of dry weight and diametre of the colony, intensity of respiration, amino acids and nitrogen content in dry mycelial mass. The influence of SO&lt;sub&gt;2&lt;/sub&gt; on mycelium growth in dependence on its age and pH of substrate was also investigated.

Direct Solid-State Fermentation of Soybean Processing Residues for the Production of Fungal Chitosan by Mucor rouxii

The feasibility of utilizing soybean-processing residues such as soybean meal and hulls as substrates for chitosan production by the fungus Mucor rouxii ATCC 24905 via solid-state fermentation (SSF) was investigated. The effects of the type of soybean-based substrate, length of cultivation period, substrate moisture content, substrate pH, incubation temperature and extraction conditions on chitosan yield were determined. The results showed that a maximum fungal chitosan yield of up to 3.44% by dry substrate weight (34.4 g/kg) could be achieved using a pure soybean meal substrate with an initial moisture content of 50% (w/w) and pH of 5 - 6 incubated for six days at 25&degC. A more severe heat treatment (autoclaving vs. refluxing) resulted in higher chitosan extraction yields regardless of the strength of extraction reagents. Fourier transform infrared (FTIR) analysis of the fungal chitosan revealed its degree of deacetylation (DDA) to be between 55% and 60%.