Optimisation of growth conditions for maximum degradation of poly βhydroxyl butrate by two soil fungi

Poly β- hydroxyl butrate (PHB) is a polymer produced by bacteria and can be used safely in different modern application to replace biobased plastic which has adverse effects on the environments. This study is aimed to isolate some fungi for PHB degradation and optimise the growth conditions for maximum degradation. Contaminated soil samples were collected from the industrial area of Jeddah and used for fungal isolations. All fungal isolates were screened for PHB biodegradation on solid agar medium. Out of 20 isolates, 2 isolates were the most active in PHB degradation. They were identified as Trichoderma asperellum NM 6, and Aspergillus fumigates NM10 using morphological and molecular methods. The effects of some growth factors on growth and PHB degradation by the two isolated fungi were determined. Growth was measured by either CPV (ml) or dry weight (g/l) while PHB degradation was detected by depolymerase assay (U/ml). Presence of yeast extract (2.5 g/l) and glucose (1 g/l) enhanced both growth and PHB degradation by the two isolates. Similarly, adjusting medium pH at 7-7.5 and incubation at 25°C after for five days led to maximum growth and PHB degradation. The presence of PHB in growth medium enhanced both growth and PHB degradation and the maximum growth (CPV ml or dry weight (g/l) were in medium containing 0.5 g/l of PHB for both tested fungi. The maximum growth, measured by either CPV (ml) or dry weight (g/l), was in the medium that was inoculated with 10x106 spore/ml for the two tested fungi. In conclusion, PHB degradation by the two tested fungi was similar. It was affected by the same physical and biochemical factors and optimisation of these conditions enhanced both growth and degradation process by the two tested fungi.

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Isolation and Molecular Identification of Phenol Degrading Bacterium from Industrial Wastes, Collected from Jeddah Saudi Arabia

Bioscience Biotechnology Research Communications ◽

10.21786/bbrc/14.4.90 ◽

2021 ◽

Vol 14 (4) ◽

pp. 1992-2001

Author(s):

Bothaina A. Alaidaroos

Keyword(s):

Phenol Degradation ◽

Carbon Sources ◽

Dry Weight ◽

Degradation Process ◽

Industrial Area ◽

Growth Conditions ◽

Industrial Wastes ◽

Aquatic Life ◽

Environment And Health ◽

Degrading Bacterium

In the past two decades, phenolic compounds have had different applications, however their use in densification has increased considerably due to Covid 19. Discharge of these dangerous materials is highly toxic and causes risk and severe problems to the environment and health of human and animals, in addition to it being harmful to the aquatic life. Phenol degradation is very important due to high toxicity and stability. The aim of this study is to isolate phenol-degrading aerobic bacteria from hydrocarbon contaminated soil or wastewater, collected from the industrial area of Jeddah. Minimal medium containing phenol as carbon source was used to isolate different bacteria. About 30 actinomycete isolates were obtained, purified and preserved on Starch nitrate. Out of 30 isolates, eight isolates (27%) grow well in medium containing 0.1% phenol. After growing in broth medium, isolate BA4 and isolate BA8 were very active in phenol degradation. Growth and phenol degradation was measured in liquid medium for the two isolates. Morphological and physiological characters of these isolates were detected using different methods. Using molecular methods, they were belonging to a genus of actinomycetes. They were identified as Streptomyces flavabus BA4 and Streptomyces sp. BA8.The effects of some growth factors on growth and phenol degradation were determined. Growth was measured by dry weight (mg/l) while phenol degradation was detected by assaying the residual phenol concentration. The presence of electron donors such as glucose, starch, glycine, peptone, and Na acetate affect both growth and phenol degradation. It was clear that addition of 1 g/l peptone enhanced both growth and phenol degradation. The isolate use phenol and its derivatives m-cresol and o-cresol as carbon sources and addition of vitamin B complex increased the bacterial growth. In conclusion, phenol degradation was detected by actinobacteria and was affected by some physical and biochemical factors. It was noticed that optimization of growth conditions enhanced both growth and phenol degradation by the two selected Streptomyces isolate. Degradation process by isolate BA4 could be a promising solution for removal of phenol from wastewater.

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Impact of Temperature, Osmotic Potential, and Osmoregulant on the Growth of Three Ectotrophic Root-Infecting Fungi of Kentucky Bluegrass

Plant Disease ◽

10.1094/pdis.1997.81.8.873 ◽

1997 ◽

Vol 81 (8) ◽

pp. 873-879 ◽

Cited By ~ 4

Author(s):

Karen A. Plumley ◽

Ann B. Gould ◽

Bruce B. Clarke

Keyword(s):

Osmotic Potential ◽

Agar Medium ◽

Fungal Growth ◽

Dry Weight ◽

Kentucky Bluegrass ◽

Magnaporthe Poae ◽

Daily Rate ◽

Solid Agar ◽

Leptosphaeria Korrae ◽

Osmotic Potentials

Two isolates each of Magnaporthe poae, Gaeumannomyces incrustans, and Leptosphaeria korrae were grown at 25°C in liquid shake culture in minimal salts medium (-0.12 MPa) or minimal salts medium adjusted to -0.5 MPa with KCl, MgCl2, or polyethylene glycol (PEG). Fungal dry weight of all three species was greater in minimal salts medium amended to -0.5 MPa with MgCl2 than in nonamended medium, and dry weight in medium amended with PEG was not different from dry weights in nonamended medium or medium amended with KCl. Fungi were incubated at varying temperatures on a minimal salts solid-agar medium (-0.12 MPa) adjusted to osmotic potentials ranging from -0.5 to -5.0 MPa with KCl or MgCl2. Optimum growth of M. poae, G. incrustans, and L. korrae on nonamended medium occurred at 30, 30, and 25°C, respectively. At optimum temperatures for each species, fungal growth was greatest at the higher osmotic potentials tested (-0.5 to -1.0 MPa) and decreased in a linear manner as osmotic potential decreased. In most cases, growth was detected at the lowest osmotic potential measured (-5.0 MPa). The relationship of fungal growth to osmotic potential depended on both temperature and osmoregulant. At temperatures optimal or nearly optimal for fungal development, the growth of all three fungi declined more rapidly with decreasing osmotic potential when grown on medium amended with MgCl2 than on medium amended with KCl. At the highest temperature evaluated for growth of M. poae and L. korrae (35 and 30°C, respectively), growth on medium amended with KCl was curvilinear and peaked at osmotic potentials of -2.5 to -3.0 MPa. Furthermore, between osmotic potentials of -2.0 and -5.0 MPa, M. poae grew best at 35°C. When maintained on nonamended minimal salts medium (-0.12 MPa) in liquid culture at 25°C or on nonamended solid-agar medium at temperatures optimal for growth, M. poae grew at a faster daily rate than L. korrae.

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Comparison of Agar and an Agitated, Thin-film, Liquid System for Micropropagation of Ornamental Elephant Ears

HortScience ◽

10.21273/hortsci.39.5.1088 ◽

2004 ◽

Vol 39 (5) ◽

pp. 1088-1092 ◽

Cited By ~ 12

Author(s):

Jeffrey Adelberg ◽

Joe Toler

Keyword(s):

Thin Film ◽

Growth Medium ◽

Agar Medium ◽

Dry Weight ◽

Liquid System ◽

Multiplication Rate ◽

Film Culture ◽

Agar Culture ◽

Solid Agar ◽

Semi Solid

Micropropagation of black-stemmed elephant ear (C. esculenta (L.) Schott `Fontanesii')' and upright elephant ear (A. macrorrhizos G. Don) were compared in semi-solid agar media and agitated, liquid thin-film bioreactor vessels at four explant densities (33, 100, 165, and 330 explants/L of media) using two growth regulator combinations: 1) 1 μm benzylaminopurine (BA)—growth medium, and 2) 3 μm BA plus 3 μm ancymidol—multiplication medium. The thin-film liquid system outperformed agar culture for most measured responses. Some exceptions were relative dry weights at higher explant densities and multiplication rate of Colocasia. When the thin-film liquid system was compared to agar culture, Alocasia explants produced their greatest biomass and had the least residual sugar at the highest explant density. Alocasia explants multiplied most rapidly and had the greatest relative dry weight on liquid media at the low explant densities. Alocasia plants were larger in growth medium than multiplication medium and larger in liquid medium than agar medium. When compared to agar, Colocasia in the thin-film liquid system produced the greatest biomass at the highest explant density in growth medium, had the greatest relative dry weight at the lowest explant density, and used the most sugar at the highest explant density. Alocasia and Colocasia would likely produce greater fresh and dry weight at the highest explant density if additional sugar were supplied during thin-film culture. Greater growth in thin-film culture of Alocasia and Colocasia is due in part, to greater availability of sugar in liquid compared to agar medium.

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Mineral nutrition, dinitrogen fixation, and growth of Alnuscrispa and Alnusglutinosa

Canadian Journal of Forest Research ◽

10.1139/x85-138 ◽

1985 ◽

Vol 15 (5) ◽

pp. 855-861 ◽

Cited By ~ 14

Author(s):

G. Prégent ◽

C. Camiré

Keyword(s):

Mineral Nutrition ◽

Dry Weight ◽

Optimal Growth ◽

Maximum Growth ◽

Dinitrogen Fixation ◽

Weight Basis ◽

Critical Levels ◽

N Status

Invitro cultures of Alnuscrispa (Ait.) Pursh and Alnusglutinosa (L.) Gaertn. were used to estimate critical foliage levels of selected nutrients for optimal growth and dinitrogen (N2) fixation. For A. crispa to obtain 90% of maximum growth and N2 fixation, foliar levels of 0.12% P, 0.13% Mg, <0.31% K, and <0.04% Ca on a dry weight basis were needed. For A. glutinosa, the critical levels were 0.138% P, 0.10% Mg, 0.29% Ca, and ~0.20% K. From all the deficiencies observed, P had the more pronounced effects on N status of both species.

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Bicarbonate for microalgae cultivation: a case study in a chlorophyte, Tetradesmus wisconsinensis isolated from a Norwegian lake

Journal of Applied Phycology ◽

10.1007/s10811-021-02420-4 ◽

2021 ◽

Author(s):

Ikumi Umetani ◽

Eshetu Janka ◽

Michal Sposób ◽

Chris J. Hulatt ◽

Synne Kleiven ◽

...

Keyword(s):

Fatty Acids ◽

Fatty Acid ◽

Lipid Production ◽

Cetane Number ◽

Fluorescence Analysis ◽

Dry Weight ◽

Maximum Growth ◽

Biodiesel Fuel ◽

Fatty Acid Production ◽

Total Fatty Acids

AbstractBicarbonate was evaluated as an alternative carbon source for a green microalga, Tetradesmus wisconsinensis, isolated from Lake Norsjø in Norway. Photosynthesis, growth, and lipid production were studied using four inorganic carbon regimes: (1) aeration only, (2) 20 mM NaHCO3, (3) 5% (v/v) CO2 gas, and (4) combination of 20 mM NaHCO3 and 5% CO2. Variable chlorophyll a fluorescence analysis revealed that the bicarbonate treatment supported effective photosynthesis, while the CO2 treatment led to inefficient photosynthetic activity with a PSII maximum quantum yield as low as 0.31. Conversely, bicarbonate and CO2 treatments gave similar biomass and fatty acid production. The maximum growth rate, the final cell dry weight, and total fatty acids under the bicarbonate-only treatment were 0.33 (± 0.06) day−1, 673 (± 124) mg L−1 and 75 (± 5) mg g−1 dry biomass, respectively. The most abundant fatty acid components were α-linolenic acid and polyunsaturated fatty acids constituting 69% of the total fatty acids. The fatty acid profile eventuated in unsuitable biodiesel fuel properties such as high degree of unsaturation and low cetane number; however, it would be relevant for food and feed applications. We concluded that bicarbonate could give healthy growth and comparative product yields as CO2.

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Incorporation of alternative amino acids into cyanophycin by different cyanophycin synthetases heterologously expressed in Corynebacterium glutamicum

AMB Express ◽

10.1186/s13568-021-01217-5 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Ramona Wördemann ◽

Lars Wiefel ◽

Volker F. Wendisch ◽

Alexander Steinbüchel

Keyword(s):

Amino Acids ◽

Dry Weight ◽

Growth Conditions ◽

Amino Acid Biosynthesis ◽

Water Soluble ◽

Lysine Content ◽

Polyaspartic Acid ◽

Acid Biosynthesis ◽

Cyanophycin Synthetase ◽

Potential Precursor

AbstractCyanophycin (multi-l-arginyl-poly-l-aspartic acid; also known as cyanophycin grana peptide [CGP]) is a biopolymer that could be used in various fields, for example, as a potential precursor for the synthesis of polyaspartic acid or for the production of CGP-derived dipeptides. To extend the applications of this polymer, it is therefore of interest to synthesize CGP with different compositions. A recent re-evaluation of the CGP synthesis in C. glutamicum has shown that C. glutamicum is a potentially interesting microorganism for CGP synthesis with a high content of alternative amino acids. This study shows that the amount of alternative amino acids can be increased by using mutants of C. glutamicum with altered amino acid biosynthesis. With the DM1729 mutant, the lysine content in the polymer could be increased up to 33.5 mol%. Furthermore, an ornithine content of up to 12.6 mol% was achieved with ORN2(Pgdh4). How much water-soluble or insoluble CGP is synthesized is strongly related to the used cyanophycin synthetase. CphADh synthesizes soluble CGP exclusively. However, soluble CGP could also be isolated from cells expressing CphA6308Δ1 or CphA6308Δ1_C595S in addition to insoluble CGP in all examined strains. The point mutation in CphA6308Δ1_C595S partially resulted in a higher lysine content. In addition, the CGP content could be increased to 36% of the cell dry weight under optimizing growth conditions in C. glutamicum ATCC13032. All known alternative major amino acids for CGP synthesis (lysine, ornithine, citrulline, and glutamic acid) could be incorporated into CGP in C. glutamicum.

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Xanthones Production in Gentiana dinarica Beck Hairy Root Cultures Grown in Simple Bioreactors

Plants ◽

10.3390/plants10081610 ◽

2021 ◽

Vol 10 (8) ◽

pp. 1610

Author(s):

Branka Vinterhalter ◽

Nevena Banjac ◽

Dragan Vinterhalter ◽

Dijana Krstić-Milošević

Keyword(s):

Hairy Root ◽

Large Scale ◽

Bubble Column ◽

Growth Parameters ◽

Growth Index ◽

Dry Weight ◽

Growth Conditions ◽

Good Growth ◽

Gentiana Dinarica ◽

Hairy Root Clones

The hairy root clones of Gentiana dinarica cl-B, cl-D, cl-3, and cl-14 were cultivated in parallel in diverse simple bioreactors, including temporary immersion systems RITA® (TIS RITA®), bubble column bioreactors (BCB), and Erlenmeyer flasks (EF), and evaluated for biomass production and xanthone content. The obtained results showed that TIS RITA® and BCB containing ½ MS medium with 4% sucrose provided equally good growth conditions in which the majority of the clones displayed the higher percentage of dry matter (DM%), and xanthones norswertianin-1-O-primeveroside (nor-1-O-prim) and norswertianin production than those cultivated in EF. Thin and well branched hairy root clone cl-B grown in BCB for 7 weeks was superior regarding all growth parameters tested, including growth index (19.97), dry weight (2.88 g), and DM% (25.70%) compared to all other clones. Cl-B cultured in TIS RITA® contained the highest amount of nor-1-O-prim (56.82 mg per vessel). In BCB with constant aeration, cl-B accumulated the highest norswertianin content reaching 18.08 mg/vessel. The optimized conditions for cultivation of selected G. dinarica hairy root clones in highly aerated TIS RITA® and BCB systems contribute to the development of bioreactor technology designed for the large scale commercial production of xanthones nor-1-O-prim and norswertianin.

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Effects of crop rotations on microbial community in rhizosphere soil of cucumber seedlings and its feedback

Allelopathy Journal ◽

10.26651/allelo.j/2021-52-2-1318 ◽

2021 ◽

Vol 52 (2) ◽

pp. 239-250

Author(s):

X.J. He ◽

W.W. Zhu ◽

F.Z. Wu

Keyword(s):

Soil Fungi ◽

Dry Weight ◽

Crop Rotations ◽

Kidney Bean ◽

Absolute Abundance ◽

Cucumber Seedlings ◽

Soil Microbial ◽

Plant Soil ◽

Significant Difference ◽

Soil Feedback

We studied the effects of 7-crop rotations and continuous - monocropping systems on soil microorganism and its feedback. The results showed that absolute abundance of soil bacteria (Pseudomonas and Bacillus) in tomato - celery - cucumber - cabbage and cucumber - tomato - cucumber - cabbage rotation were significantly higher than control (CK). Absolute abundance of soil fungi in tomato - celery - cucumber - cabbage, kidney bean - celery - cucumber - cabbage, cucumber - kidney bean - cucumber - cabbage and cucumber - tomato - cucumber - cabbage rotation were significantly higher than CK. Dry weight of cucumber seedlings was significantly positively correlated with bacterial (Pseudomonas and Bacillus) abundance, and negatively correlated with fungal count. The results of inoculation with Fusarium oxysporum f.sp. cucumerinum showed that plant dry weight of cucumber seedlings in tomato - celery - cucumber - cabbage, cucumber - kidney bean - cucumber - cabbage, cucumber - tomato - cucumber - cabbage rotation soil was significantly higher than other treatments, and their disease index was significantly lower than other treatments. There was no significant difference in dry weight of cucumber seedlings in rotation and CK in the soil sterilization test. The results of plant - soil feedback experiment showed that soil microbial changes caused by different rotation patterns had a positive feedback effect on growth of cucumber seedlings.

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Factors Influencing Geosmin Production by the Cyanobacterium Oscillatoria Brevis

Water Science & Technology ◽

10.2166/wst.1988.0233 ◽

1988 ◽

Vol 20 (8-9) ◽

pp. 125-131 ◽

Cited By ~ 17

Author(s):

H. Naes ◽

H. C. Utkilen ◽

A. F. Post

Keyword(s):

Environmental Factors ◽

Dry Weight ◽

Growth Conditions ◽

Limited Extent ◽

Limited Growth ◽

Pigment Synthesis ◽

Factors Affecting ◽

Culture Techniques ◽

Factors Influencing ◽

Effect Of Inhibitors

Environmental factors affecting geosmin production by Oscillatoria brevis have been investigated under laboratory conditions using continuous culture techniques. Transition from light to nutrient limited growth conditions caused a two-fold decrease in geosmin production. However, geosmin content increased relative to pigment content (chlorophyll a and carotenoids). It has been suggested that geosmin biosynthesis in O. brevis proceeds via the isoprenoid pathway as was found in actinomycetes. Accordingly, we investigated the effect of inhibitors of the intermediate stages in this synthetic pathway in order to study the regulation of geosmin production in relation to pigment synthesis. It was concluded that geosmin seemed to function as an overflow metabolite in this pathway. Due to the only modest changes in geosmin production per dry weight compared to changes in biomass levels during light- or nutrient limited growth, contamination of eutrophic fresh waters with geosmin appears to depend mainly on the species present and its biomass level and only to a limited extent on nutrient enhanced synthesis.

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Pengaruh Pemberian Zeolite dan Dosis Pupuk Nitrogen Terhadap Pertumbuhan Vegetatif Jagung (Zea mays, L.) di Media Pasir Pantai

Planta Tropika Journal of Agro Science ◽

10.18196/pt.v1i1.3111 ◽

2021 ◽

Vol 1 (1) ◽

pp. 39-43

Author(s):

Gunawan Budiyanto ◽

Mulyono Mulyono ◽

Fiyoni Dwi Setyawan

Keyword(s):

Plant Height ◽

Sandy Soil ◽

Nitrogen Fertilizer ◽

Vegetative Growth ◽

Dry Weight ◽

Maximum Growth ◽

Fertilizer Application ◽

Research Field ◽

Maize Crop ◽

Randomized Design

A research to study the effects of Zeolite and nitrogen fertilizer application on vegetative growth of maize crop in coastal sandy soil was conducted on the research field of Agriculture Faculty, Muhammadiyah University of Yogyakarta at Tamantirto, Bantul District of Yogyakarta during October until February, 2003. This research was aimed on the study of Zeolite application in order to enhance the nitrogen uptake in the coastal sandy soil, and its effects on vegetative growth of CP I variety of maize. The pot experiment was arranged in 7 x 3 factorial completely randomized design, with 4 replications. The first factor was Zeolite dosage consisted of 7 levels, i.e: 0, 3, 4, 5, 6, 7, and 8 %; and the second one was 3 levels nitrogen fertilizer dosage which consisted of: 75, 110, and 145 kg/ ha. The nitrogen fertilizer was applied on the medium mixed with Zeolite granules. Observations on plant height, stem diemeter, leaves number, plant fresh and dry weight were done during the vegetative growth of maize. The results showed that Zeolite application significantly enhanced the vegetative growth of CPI maize. The 5,2 - 5,6 % Zeolite was optimum to gave the maximum growth of maize crop. Nitrogen fertilizer application was also significantly increased the plant height and biomass weight, and the 145 kg/ha was the optimum dosage. There was no interaction between Zeolite and nitrogen fertilizer application in order to affected the maize growth.

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