Potential of a mixed culture of microalgae for accumulation of beta-carotene under different stress conditions

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Azita Ghorbani ◽  
Poorya Rafiee ◽  
Maryam Hosseini ◽  
Sirous Ebrahimi
Keyword(s):  
Light Intensity ◽  
Mixed Culture ◽  
Nitrogen Starvation ◽  
Beta Carotene ◽  
Stress Conditions ◽  
Carotene Content ◽  
Pure Cultures ◽  
Chlorophyll Production ◽  
First Time ◽  
Good Substitute

Abstract Beta-carotene, a pigment found in plants, is mainly produced by microalgae. Nevertheless, this production has only been investigated in pure cultures. Beta-carotene production through mixed culture eliminates the costly procedure of sterilization and contamination prevention needed for pure cultures. In this study, for the first time, the growth, beta-carotene, and chlorophyll production of a mixed culture of microalgae from Caspian Sea was investiagted under different stress conditions. At the condition of tripled light intensity and nitrogen starvation, beta-carotene content increased from 18.03 to 43.8 and 46.5 mol beta-carotene g−1 protein, respectively. However, the salinity of 4 mol L−1 caused the beta-carotene content to fall to zero. The blank sample reached a constant value of 23 mol beta-carotene g−1protein. The comparable results with the specific monoculture species exhibit the high potential of a mixed culture of microalgae for beta-carotene production without need of the high sterilization cost. Nevertheless, more research is needed for where it can be a good substitute for pure culture.

scholarly journals An alternative methionine aminopeptidase, MAP-A, is required for nitrogen starvation and high-light acclimation in the cyanobacterium Synechocystis sp. PCC 6803

Microbiology ◽  
2009 ◽  
Vol 155 (5) ◽  
pp. 1427-1439 ◽  
Author(s):  
Miriam Drath ◽  
Kerstin Baier ◽  
Karl Forchhammer
Keyword(s):  
Photosystem Ii ◽  
Nitrogen Starvation ◽  
Light Exposure ◽  
Housekeeping Gene ◽  
High Light ◽  
Stress Conditions ◽  
Methionine Aminopeptidases ◽  
Living Organisms ◽  
First Time ◽  
Pcc 6803

Methionine aminopeptidases (MetAPs or MAPs, encoded by map genes) are ubiquitous and pivotal enzymes for protein maturation in all living organisms. Whereas most bacteria harbour only one map gene, many cyanobacterial genomes contain two map paralogues, the genome of Synechocystis sp. PCC 6803 even three. The physiological function of multiple map paralogues remains elusive so far. This communication reports for the first time differential MetAP function in a cyanobacterium. In Synechocystis sp. PCC 6803, the universally conserved mapC gene (sll0555) is predominantly expressed in exponentially growing cells and appears to be a housekeeping gene. By contrast, expression of mapA (slr0918) and mapB (slr0786) genes increases during stress conditions. The mapB paralogue is only transiently expressed, whereas the widely distributed mapA gene appears to be the major MetAP during stress conditions. A mapA-deficient Synechocystis mutant shows a subtle impairment of photosystem II properties even under non-stressed conditions. In particular, the binding site for the quinone QB is affected, indicating specific N-terminal methionine processing requirements of photosystem II components. MAP-A-specific processing becomes essential under certain stress conditions, since the mapA-deficient mutant is severely impaired in surviving conditions of prolonged nitrogen starvation and high light exposure.

Cas de suie de l'érable et de chancre du peuplier dans le canton de Genève

2016 ◽  
Vol 167 (2) ◽  
pp. 98-104
Author(s):  
Bastien Cochard ◽  
François Lefort
Keyword(s):  
Internal Transcribed Spacer ◽  
Pathogenic Fungi ◽  
Fungal Flora ◽  
Acer Campestre ◽  
Cytospora Chrysosperma ◽  
Pure Cultures ◽  
Populus X Euramericana ◽  
Bark Peeling ◽  
Specific Symptoms ◽  
First Time

A case of sooty bark disease and Cytospora poplar canker in the Canton of Geneva In summer 2014, a case of sooty bark disease caused by Cryptostroma corticale on an individual field maple (Acer campestre) and two cases of poplar canker due to Cytospora chrysosperma on Populus x euramericana were identified genetically for the first time on the territory of the Canton of Geneva. In both cases, the trees presented signs of very advanced dieback, accompanied by specific symptoms such as bark peeling and sooty plaques for the maple, and loose twisted bark layers and black colouring of the wood in structural branches of the poplars. Sampling was carried out in the symptomatic areas and components of the fungal flora were isolated in pure cultures in order to identify any pathogenic fungi. The molecular analysis of the rDNA internal transcribed spacer (ITS) sequences made it possible to identify precisely all pure isolates obtained. The results showed a majority presence of C. corticale in the maple tree, and of C. chrysosperma in the two poplars. Both these fungi are little known in Switzerland and Europe, and their presence is maybe associated with changes in the climate.

Extracellular carbohydrate liberation in the flagellates Isochrysis galbana and Prymnesium parvum

1965 ◽  
Vol 45 (3) ◽  
pp. 755-772 ◽  
Author(s):  
A. F. H. Marker
Keyword(s):  
Organic Matter ◽  
Light Intensity ◽  
Nitrogen Starvation ◽  
Axenic Culture ◽  
Isochrysis Galbana ◽  
Prymnesium Parvum ◽  
Extracellular Production ◽  
Low Light ◽  
Passive Release ◽  
Dying Cells

The production of extracellular carbohydrate has been studied in Isochrysis galbana and Prymnesium parvum in axenic culture. Increased extracellular production of carbohydrate occurred at reduced and increased salinity, low light intensity and under conditions of nitrogen starvation in Isochrysis, and in some cases appeared to be associated with the sedimentation of the cells from stagnant culture. Extracellular carbohydrate production was found to be greatest during the early and later stages in growth and dropped to a minimum during the mid-growth phase. Experiments indicated that the cells were not being damaged during harvesting of the cultures. A close similarity was found between the monosaccharide components of the intra- and extracellular carbohydrate after acid hydrolysis; both contained glucose, galactose, arabinose, xylose and ribose. It is suggested that the production of most of the extracellular carbohydrate is due to the passive release of organic matter from dead or dying cells.

Retinol and beta carotene content of indigenous raw and home-prepared foods in Northeast Thailand

1999 ◽  
Vol 64 (2) ◽  
pp. 163-167 ◽  
Author(s):  
Pongtorn Sungpuag ◽  
Sommai Tangchitpianvit ◽  
Uraiporn Chittchang ◽  
Emorn Wasantwisut
Keyword(s):  
Beta Carotene ◽  
Northeast Thailand ◽  
Carotene Content

Vitamins A, C, and E and beta-Carotene Content in Seeds of Seven Species of Vicia L.

2005 ◽  
Vol 47 (4) ◽  
pp. 487-493 ◽  
Author(s):  
Ahmet SAHIN ◽  
Yasar KIRAN ◽  
Fikret KARATAS ◽  
Senem SONMEZ
Keyword(s):  
Beta Carotene ◽  
Carotene Content

scholarly journals Growth Inhibition of Cocoa Pod Rot Fungus Phytophthora palmivora byPseudomonas fluorescence and Bacillus subtilis bacteria

2013 ◽  
Vol 29 (2) ◽  
Author(s):  
Sakti Widyanta Pratama ◽  
Sri Sukamto ◽  
Lis Nur Asyiah ◽  
Yeni Vida Ervina
Keyword(s):  
Bacillus Subtilis ◽  
Fungal Growth ◽  
Petri Dish ◽  
Phytophthora Palmivora ◽  
Fungal Treatment ◽  
Pure Cultures ◽  
Black Pod ◽  
Black Pod Disease ◽  
First Time ◽  
Important Disease

Black pod disease caused by Phytophthora palmivorafungus is one of the important diseases on cocoa crop. Pod rot is the most important disease because it may cause loss of cocoa pod. Until now, the fungal pathogen of cocoa black pod disease is still a crucial problem and there is no fungicide that is really effective against the disease. One alternative to control the cocoa black pod disease is by using biological agents as biofungicide, including utilizing Pseudomonas fluorescenceand Bacillus subtilis bacteria. The research was done by isolation of P. palmivora from infected pods of Kaliwining Experimental Station to obtain pure cultures of fungus and by multiplication of P. fluorescence and B. subtilis. Antagonist test was performed by inoculating P. palmivora into a petri dish in a distance of 3 cm from the edge. P. fluorescenceand B. Subtilis were inoculated into petridishes in three days after the fungal treatment. Control was inoculated with isolate of P. palmivora only. Fungal growth was measured everyday by measuring radius of fungal colonies first time 24 hours after inoculation. Growth of Phytophthora palmivora in the two treatmens were used to calculate the percentage of inhibition. The results of this study indicated that P. fluorescence and B. subtiliswere able to inhibit fungal growth of P. palmivora. Both bacterial antagonists had the same effectiveness in inhibiting the growth of P. palmivora fungus based on the percentage of inhibition and effectiveness criteria. Based on the results of translucent zones indicated that B. subtiliswas more powerfull in inhibiting growth of P. Palmivora compared to P. fluorescence. Key words: Black pod disease of cocoa, biological control, Phytophthora palmivora, Pseudomonas fluorescence, Bacillus subtilis

scholarly journals Changes in biologically active substances of stone fruits under the influence of low temperatures

2021 ◽  
Vol 34 ◽  
pp. 06017
Author(s):  
Irina Sobol ◽  
Ludmila Rodionova ◽  
Ludmila Donchenko ◽  
Artem Stepovoy
Keyword(s):  
Low Temperatures ◽  
Beta Carotene ◽  
Biologically Active Substances ◽  
Biologically Active ◽  
Carotene Content ◽  
Plum Varieties ◽  
Physical And Chemical ◽  
Active Substances ◽  
Acid Reduction ◽  
Pectin Substances

Sufficient consumption of natural biologically active substances (BAS) – vitamins, dietary fiber, mineral compounds – reduces the risk of developing diseases associated with negative external factors. A large number of BAS are contained in the cherry plum fruits. Cherry plum is characterized by storage short term, during which quality changes are possible. Studies have been conducted on the low temperatures effect the change of BAS in cherry plum fruits. Studied objects were five cherry plum varieties grown in the Russian southern regions – Dinnaya, Zhemchuzhina, Obilnaya, Puteshestvennitsa, Neberdzhayskaya ranyaya. It was found that during storage, the physical and chemical parameters change slightly, the dry substances content decreases (within 1.3-3.2 %), sugars (5.5-7.0 %), the total acids content increases (2.8 3.3 %). The BAS content slight decrease during storage does not significantly affect the nutritional value of cherry plum fruits. The ascorbic acid reduction is 9.8-17.3 %, the anthocyanins content decreases on average from 16.9 to 19.7 %, the beta-carotene content decreases by 8.7-14.8 %, the reduction level of pectin substances is 15.75-22.2 %. Thus, the freezing method application allows to preserve valuable BAS in cherry plum fruits and use them in the future as a basis for the production of functional food products.

Degradation of polycyclic aromatic hydrocarbons (PAHs) by a mixed culture and its component pure cultures, obtained from PAH-contaminated soil

1995 ◽  
Vol 41 (6) ◽  
pp. 470-476 ◽  
Author(s):  
D. Trzesicka-Mlynarz ◽  
O. P. Ward
Keyword(s):  
Polycyclic Aromatic Hydrocarbons ◽  
Mixed Culture ◽  
Aromatic Hydrocarbons ◽  
Aqueous Media ◽  
Water Soluble ◽  
Nitrogen Levels ◽  
Glucose Levels ◽  
Polycyclic Aromatic ◽  
Pure Cultures ◽  
The Media

A mixed culture, isolated from soil contaminated with polycyclic aromatic hydrocarbons (PAHs), grew on and degraded fluoranthene in aqueous media supplemented with glucose, yeast extract, and peptone. Increased complex nitrogen levels in the medium promoted bacterial growth and a greater extent of fluoranthene degradation. Amendment of the media with high glucose levels also diminished specific fluoranthene degradation. The mixed culture was capable of degrading a range of other PAHs, including benzo[a]pyrene, anthracene, phenanthrene, acenaphthene, and fluorene. The mixed culture contained four predominant isolates, all of which were Gram-negative rods, three of which were identified as Pseudomonas putida, Flavobacterium sp., and Pseudomonas aeruginosa. Better degradation of a defined PAH mixture was observed with the mixed culture than with individual isolates. A reconstituted culture, prepared by combining the four individual isolates, manifested a similar PAH biodegradation performance to the original mixed culture. When compared with the mixed culture, individual isolates exhibited a relatively good capacity to remove more water-soluble PAHs (acenaphthene, fluorene, phenanthrene, fluoranthene). In contrast, removal of less water-soluble PAHs (anthracene and pyrene) was low or negligible with isolated cultures compared with the mixed culture.Key words: polycyclic aromatic hydrocarbons, mixed culture, fluoranthene, Pseudomonas, Flavobacterium.

scholarly journals Polyphenolic composition and invitro evaluation of radical scavenging and anti diabetic properties of Canthium parviflorum

2020 ◽  
Vol 11 (SPL4) ◽  
pp. 1056-1061
Author(s):  
Azhagu Saravana Babu P ◽  
Vajiha Aafrin B ◽  
Renuka V ◽  
Shalini Priyanga C ◽  
Pooja D ◽  
...  
Keyword(s):  
Aqueous Extract ◽  
Radical Scavenging ◽  
Beta Carotene ◽  
Total Phenolic ◽  
Carotene Content ◽  
Plant Materials ◽  
Polyphenolic Composition ◽  
Anti Oxidant ◽  
Nutritional Compounds ◽  
Radical Scavenging Properties

The main objective of the present study was to investigate the nutraceutical properties of the bioactive components from the extracts of Canthium parviflorum seeds (CPS). The anti-oxidant property of CPS extracts was carried out by estimating the total phenolic, flavonoid contents, flavonols, flavonols and radical scavenging properties. The results of these findings show that the aqueous extract of CPS rich in polyphenols (87.5 ± 0.2 mg GAE /g) and flavonoids (50.1 ± 0.2 mg QE/g) compounds than organic extracts. The effective inhibitory activity of CPS against α- amylase and α- glucosidases enzyme related to type- 2 diabetes was evaluated and compared. The aqueous extract was exhibited the maximum α-amylase and β-glucosidase inhibition of 91.1 ± 0.4 and 90.5 ± 0.1 % respectively. The seed extracts show a maximum of 25.5 % of protein and 6.4 mg/100g of zinc. The seed extract was exhibited maximum anti-oxidant property with beta carotene content of 5.4 mg/100 g of seed. The present work may be the platform to use to develop high-value nutritional compounds by unutilized plant materials. The natural anti-oxidant and polyphenols present in the extracts were showed great nutraceutical value, and it may be used to develop nutraceutical to enhance a healthy diet.

Sign in / Sign up

Export Citation Format

Share Document