scholarly journals Effects of phosphorus on the growth and chlorophyll fluorescence of a Dunaliella salina strain isolated from saline soil under nitrate limitation

2016 ◽  
Vol 89 (2) ◽  
Author(s):  
Tassnapa Wongsnansilp ◽  
Niran Juntawong ◽  
Zhe Wu
Keyword(s):  
Dunaliella Salina ◽  
Beta Carotene ◽  
Phosphate Concentration ◽  
Carotene Content ◽  
Ps Ii ◽  
Algae Growth ◽  
Kinetics Of ◽  
Late Growth ◽  
High Phosphate ◽  
Northeastern Thailand

An isolated <em>Dunaliella salina</em> (<em>D. salina</em>) KU XI from saline soils in northeastern Thailand was cultured in f/2 medium in column photobioreactor. The variations of the growth, chlorophyll and beta-carotene content and the maximum quantum yield of PS II photochemistry (F<sub>v</sub>/F<sub>m</sub>) under different NaH<sub>2</sub>PO<sub>4</sub> concentrations were studied. Based on the results, the growth kinetics of <em>D. salina</em> KU XI was established, which could simulate the algae growth rate under different phosphate concentrations and temperatures. The phosphorus could significantly affect the growth and pigments accumulations of this isolated strain. Increasing NaH<sub>2</sub>PO<sub>4</sub> concentration improved the biomass, the total chlorophyll and beta-carotene content, retarded the decrease of F<sub>v</sub>/F<sub>m</sub> value. The optimal phosphate concentration for the growth of <em>D. salina</em> KU XI was above 72.6 μM. The maximum biomass and beta-carotene were 0.24 g L<sup>-1</sup> and 17.4 mg L<sup>-1</sup> respectively when NaH<sub>2</sub>PO<sub>4</sub> was 290.4 μM. The algae growth was restrained by phosphate or nitrate when NaH<sub>2</sub>PO<sub>4</sub> below 12.1 μM or above 72.6 μM. It indicated that properly supplementing nitrate in the late growth stage with high phosphate concentration was favored for enhancing the growth and biomass production.

The effect of audible sound frequency on the growth and beta-carotene production of Dunaliella salina

2021 ◽  
Vol 141 ◽  
pp. 373-382
Author(s):  
Arezoo Keramati ◽  
Farshid Pajoum Shariati ◽  
Omid Tavakoli ◽  
Zahra Akbari ◽  
Mina Rezaei
Keyword(s):  
Dunaliella Salina ◽  
Beta Carotene ◽  
Sound Frequency ◽  
Audible Sound

scholarly journals Photosystem II: Thermodynamics and Kinetics of Electron Transport from QA- to QB(QB- ) and Deleterious Effects of Copper(II)

1993 ◽  
Vol 48 (3-4) ◽  
pp. 234-240 ◽  
Author(s):  
G. Renger ◽  
H. M. Gleiter ◽  
E. Haag ◽  
F. Reifarth
Keyword(s):  
Oxygen Evolution ◽  
Manganese Content ◽  
Fluorescence Emission ◽  
Laser Flash ◽  
Fluorescence Induction ◽  
Oxygen Evolving Complex ◽  
Ps Ii ◽  
Thermodynamics And Kinetics ◽  
Redox Active ◽  
Kinetics Of

Studies on thermodynamics and kinetics of electron transfer from QA- to QB(QB-) were performed by monitoring laser flash induced changes of the relative fluorescence emission as a function of temperature (220 K < T < 310 K) in isolated thylakoids and PS II membrane fragments.In addition, effects of bivalent metal ions on PS II were investigated by measuring conventional fluorescence induction curves, oxygen evolution, manganese content and atrazine binding mostly in PS II membrane fragments. It was found: a) the normalized level of the fluorescence remaining 10 s after the actinic flash (Ft/F0) steeply increases at temperatures below -10 to - 20 °C, b) the fast phase of the transient fluorescence change becomes markedly retarded with decreasing temperatures, c) among different cations (Cu2+, Zn2+, Cd2+, Ni2+, Co2+) only Cu2+ exhibits marked effects in the concentration range below 100 μᴍ and d) Cu2+ decreases the normalized variable fluorescence, inhibits oxygen evolution and diminishes the affinity to atrazine binding without affecting the number of binding sites. The content of about four manganeses per functionally competent oxygen evolving complex is not changed by [Cu2+] < 70 μᴍ.Based on these findings it is concluded: i) a temperature dependent equilibrium between an inactive (I) and active (A) state of QA- reoxidation by QB(QB- ) is characterized by standard enthalpies ΔH° of 95 kJ mol-1 and 60 kJ mol-1 and standard entropies ΔS° of 370 kJ K-1 mol-1 and 240 kJ K-1 mol-1 in isolated thylakoids and PS II membrane fragments, respectively, ii) the activation energies of QA- reoxidation by plastoquinone bound to the QB site are about 30 kJ mol-1 (thylakoids) and 40 kJ mol-1 (PS II membrane fragments) in 220 K < T < 300 K, and iii) Cu2+ causes at least a two-fold effect on PS II by modifying the atrazine binding affinity at lower concentrations ( ~ 5 μᴍ) and interference with the redox active tyrosine Yz at slightly higher concentration ( ~ 10 μᴍ) leading to blockage of oxygen evolution.

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 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.

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