scholarly journals Investigation of Growth Rate and Phycocolloid Content from Kappaphycus alvarezii (Rhodophyta, Solieriaceae) under Different Light Conditions Using Vibrational Spectroscopy

2016 ◽  
Vol 4 (2) ◽  
pp. 1 ◽  
Author(s):  
Vun Yee Thien ◽  
Kenneth Francis Rodrigues ◽  
Clemente Michael Vui Ling Wong ◽  
Wilson Thau Lym Yong
Keyword(s):  
Carbon Dioxide ◽  
Growth Rate ◽  
Chemical Structure ◽  
Kappaphycus Alvarezii ◽  
Red Light ◽  
Monochromatic Light ◽  
Carbon Dioxide Concentration ◽  
Major Constituent ◽  
Light Spectrum ◽  
Spectral Profiles

<p><em>Kappa</em>-carrageenan (<em>K</em>-carrageenan) is an important phycocolloid which is a major constituent of the cell wall of <em>Kappaphycus alvarezii</em>. The chemical structure of <em>K</em>-carrageenan comprises a linear backbone of D-galactose residues linked with alternating α-(1,3) and β-(1,4) linkages which are substituted by one ester-sulphonic group per di-galactose repeating unit. The spectral qualities of light as well as the ambient carbon dioxide concentration, both play an important role in the photosynthetic pathway in plants and this investigation set forth to establish the effect of different wavelengths of light and carbon dioxide supplementation on the chemical structure of <em>K</em>-carrageenan obtained from <em>K. alvarezii. </em>Specimens were cultivated under a range of monochromatic light spectra and assessed for chemical composition using Fourier Transform Infrared (FTIR) spectroscopy.The <em>K. alvarezii</em> control was irradiated with full light spectrum, treatments were carried out using blue (492-455 nm), green (577-492 nm) and red (780-622 nm)light. One experiment was carried out by supplementation with carbon dioxide. Samples were collected after 14 days. The effect of different wavelengths of light on the growth rates of experimental samples was determined. Red light had the most significant impact on the growth rate of <em>K. alvarezii </em>as compared to those treated with blue light. The FTIR fingerprint of the ground seaweed was found to be identical to that of commercial <em>K</em>-carrageenan (Sigma). Special emphasis was given to the 800-1300 cm<sup>-1 </sup>region, which presents several vibrational modes. All the samples produced similar FTIR spectral profiles, suggesting that genes related to the carrageenan biosynthesis are not affected by different wavelengths of light or CO<sub>2</sub>. The results obtained from FTIR spectroscopy demonstrated that different wavelengths of light and supplementation with CO<sub>2</sub> have no influence to the chemical structure of <em>K</em>-carrageenan in <em>K. alvarezii</em>.</p>

scholarly journals Influence of the specific growth rate on formation of sterols in yeast Saccharomyces cerevisiae during fed-batch cultivation

2000 ◽  
Vol 18 (No. 3) ◽  
pp. 110-114
Author(s):  
J. Čermák ◽  
M. Rychtera ◽  
P. Nechvíle ◽  
J. Náhlík ◽  
K. Melzoch ◽  
...  
Keyword(s):  
Carbon Dioxide ◽  
Growth Rate ◽  
Specific Growth Rate ◽  
Control Strategy ◽  
Respiratory Quotient ◽  
Specific Growth ◽  
Carbon Dioxide Concentration ◽  
Sterol Fraction ◽  
Yeast Cells ◽  
Dry Biomass

Ergosterol is a major sterol in yeast cells. Intermediates of ergosterol biosynthesis or products of ergosterol biotransformation occur in cells too. Sterols mainly form components of cell membranes. Fluidity of membranes is affected by sterols. The amount of sterols in cells can be influenced above all by cultivation conditions and by the yeast genotype. Specific growth rate is an important factor which affects the amount of sterols present in yeast cells. We carried out a series of 24-hour cultivations to find out the impact of specific growth rate on sterol biosynthesis. Inflow of synthetic medium to the bioreactor was controlled by means of a profile of carbon dioxide concentration in the outlet gases. This profile was acquired by simulation according to a mathematical model of cultivation. Profile of carbon dioxide concentration corresponded to a precalculated profile of specific growth rate. Cultivation was divided into two phases with different growth rate values. A constant value of the specific growth rate was maintained in the 1st phase. The specific growth rate value decreased by controlling the inflow in the 2nd phase (beginning at 12th hour of cultivation). Other cultivations were carried out using so-called physiological control which consisted in determining the immediate physiological state (e.g., RQ) and the choice of control strategy according to the metabolic state. Selected control strategy ensures an immediate action (inflow of the medium). If the specific growth rate decreased in the 1st phase, the amount of total sterols in yeast dry biomass increased (to 2.7% in yeast dry biomass). But the purity of ergosterol decreased (amount of sterol contaminants increased up to 23.3% in the sterol fraction). If a constant value of respiratory quotient was maintained (at about 1.1), the amount of total sterols in yeast dry biomass and the purity of ergosterol were constant. If the value of respiratory quotient was changed in the growth and final phase of cultivation, the amount of total sterols in yeast dry biomass increased (to 2.83% in yeast dry biomass). However, the purity of ergosterol decreased (amount of sterol contaminants increased up to 21.2% in sterol fraction).

Enhanced Microalgal Lipid Production in Internally Illuminated Airlift Photobioreactor

2019 ◽  
Vol 53 (2) ◽  
pp. 38-45
Author(s):  
Irem Deniz ◽  
Zeliha Demirel ◽  
Esra Imamoglu ◽  
Meltem Conk Dalay
Keyword(s):  
Fatty Acids ◽  
Growth Rate ◽  
Blue Light ◽  
Lipid Content ◽  
White Light ◽  
Lipid Production ◽  
Red Light ◽  
Light Spectrum ◽  
Light Supply ◽  
Total Fatty Acids

AbstractInternal illumination systems are being considered for use as an alternative light supply technique in microalgal products. The main goal of the study was to analyze the roles of different light wavelengths in internally illuminated airlift photobioreactors (PBRs) providing the light energy in an efficient way for the biomass production, lipid yield, and fatty acid composition of Amphora capitellata. The maximum chlorophyll-a concentration per unit biomass (2.62 ± 0.16 mg L−1) was obtained under red light, which was only 14% higher than under blue light in internally illuminated airlift PBR, whereas low chlorophyll-a content was found under white light. Maximum specific growth rate of 0.317 day−1, which corresponded to a doubling time of 2.185 days, was obtained under red light for A. capitellata. It was found that lipid content increased with decreasing growth rate for A. capitellata. Palmitic acid (C16:0) and palmitoleic acid (C16:1) were the principal fatty acids accounting for between 31%‐33% and 31%‐32% of total fatty acids, respectively. It is important to underline that red and blue light spectrum ranges contribute to improved biomass growth, whereas white light has the potential to support lipid content of diatoms.

scholarly journals Comparative Transcriptome Profiling of Kappaphycus alvarezii (Rhodophyta, Solieriaceae) in Response to Light of Different Wavelengths and Carbon Dioxide Enrichment

Plants ◽  
2021 ◽  
Vol 10 (6) ◽  
pp. 1236
Author(s):  
Vun Yee Thien ◽  
Kenneth Francis Rodrigues ◽  
Christopher Lok Yung Voo ◽  
Clemente Michael Vui Ling Wong ◽  
Wilson Thau Lym Yong
Keyword(s):  
Carbon Dioxide ◽  
Carbon Metabolism ◽  
Red Algae ◽  
Protein Complexes ◽  
Kappaphycus Alvarezii ◽  
Red Light ◽  
Co2 Enrichment ◽  
Transcriptome Profiling ◽  
Genomic Databases ◽  
Carbon Dioxide Co2

Rhodophyta (red algae) comprises over 6000 species, however, there have only been a few comparative transcriptomic studies due to their under-representation in genomic databases. Kappaphycus alvarezii, a Gigartinales algae, is a valuable source of carrageenan and is extensively cultivated in many countries. The majority of seaweed farming in Southeast Asia is done in intertidal zones under varying light (i.e., spectra and irradiance) and carbon dioxide (CO2) conditions, which affects the rate of photosynthesis. This study conducted transcriptome profiling to investigate the photosynthetic mechanisms in K. alvarezii exposed to different wavelengths of light (i.e., blue, green, and red light, in comparison to white light) and CO2 availability. We analyzed the responses of photosynthetic protein complexes to light and observed that light of different wavelengths regulates a similar set of photosynthetic apparatuses. Under CO2 enrichment, genes encoding C3 and C4 enzymes were found to be actively transcribed, suggesting the likely shift in the carbon metabolism pathway or the involvement of these genes in adaptive physiological processes. This study contributes to the understanding of the regulatory mechanisms of photosynthetic carbon metabolism in red algae and has implications for the culture and commercial production of these economically valuable macroalgae.

Use of Lemon Extract To Inhibit the Growth of Malolactic Bacteria

2007 ◽  
Vol 70 (1) ◽  
pp. 114-118 ◽  
Author(s):  
A. CONTE ◽  
M. SINIGAGLIA ◽  
M. A. DEL NOBILE
Keyword(s):  
Carbon Dioxide ◽  
Growth Rate ◽  
Microbial Growth ◽  
Activity Index ◽  
Carbon Dioxide Concentration ◽  
Oenococcus Oeni ◽  
Growth Cycle ◽  
Inhibitory Effect ◽  
Natural Preservative ◽  
Potential Use

The potential use of lemon extract as a natural preservative to inhibit the growth of Oenococcus oeni and Lactobacillus plantarum, microorganisms involved in the malotactic fermentation of wine, was studied. Growth tests were run at 30°C using laboratory media. Carbon dioxide concentration in the vial headspace was used as metabolic activity index of the investigated microorganisms. The MIC and the noninhibiting concentration (NIC) were calculated for each microorganism. Results suggest that lemon extract was active on each phase of the growth cycle for the tested microorganisms. It was also shown that lemon extract exhibits a nonlinear dose-related inhibitory effect on microbial growth. In particular, the active compound could be added at concentrations slightly higher than the NIC levels in order to appreciably slow down the microbial growth rate as well as to reduce the maximum microbial growth level.

scholarly journals Prenatal effects of red and blue light on physiological and behavioural parameters of broiler chickens

2021 ◽  
Author(s):  
Angelika Drozdová ◽  
Zuzana Kaňková ◽  
Boris Bilčík ◽  
Michal Zeman
Keyword(s):  
Growth Rate ◽  
Body Weight ◽  
Blue Light ◽  
Broiler Chickens ◽  
Tonic Immobility ◽  
Red Light ◽  
Monochromatic Light ◽  
Postembryonic Development ◽  
Underlying Mechanisms ◽  
Prenatal Effects

Light during incubation can influence embryonic and postembryonic development of chickens, but the underlying mechanisms are poorly understood. Previous studies have demonstrated that red and blue lights during incubation had opposite effects on the development of embryonic melatonin biosynthesis; red light results in the highest and blue light in the lowest amplitude of the daily rhythm. Therefore, in this study, we investigated if exposure to monochromatic red (632 nm) and blue (463 nm) light during incubation can differently influence growth, selected biochemical (glucose, cholesterol, triacylglycerols) and endocrine (corticosterone and thyroid hormones) traits and behavioural parameters during postembryonic development in broiler chickens. For analysis, we used 10 and 11 hatchlings incubated in red and blue light, respectively and 10 birds per each group (six males and four females) in 3-weeks-old broilers. During the rapid growth phase (days 18, 20 and 21 of age), higher body weight was recorded in broilers incubated under red compared to blue light, whereas endocrine and metabolic traits did not differ between the treatments. The improved growth rate was related to behavioural traits, mainly because chickens incubated in red light exhibited more passive (resting, standing, preening, dust bathing) and less active behaviours (walking, foraging, fighting, wing-flapping) than the blue-light incubated birds. The time spent for eating and drinking and the results of the tonic immobility test did not differ between both groups. Our results suggest that red and blue monochromatic light during incubation can differently program the postembryonic development of broilers, with possible consequences for their growth and welfare.

scholarly journals Dim Red Light During Scotophase Enhances Mating of a Moth Through Increased Male Antennal Sensitivity Against the Female Sex Pheromone

2021 ◽  
Vol 12 ◽  
Author(s):  
Qiuying Chen ◽  
Xi Yang ◽  
Dongrui You ◽  
Jiaojiao Luo ◽  
Xiaojing Hu ◽  
...  
Keyword(s):  
Sex Pheromone ◽  
Binding Protein ◽  
Red Light ◽  
Monochromatic Light ◽  
Female Sex Pheromone ◽  
Light Spectrum ◽  
Light At Night ◽  
Expression Levels ◽  
Female Sex ◽  
Yellow Peach Moth

Insects are behaviorally and physiologically affected by different light conditions, including photoperiod, light intensity, and spectrum. Light at night has important influences on nocturnal insects, including most moth species. Moth copulation and mating usually occur at night. Although a few studies examine changes in insect mating under artificial light at night, detailed influences of light, such as that of monochromatic light, on moth mating remain largely unknown. In this study, on the basis of long-term insects rearing experience, dim red light (spectrum range: 610–710nm, with a peak at 660nm; 2.0 Lux) during scotophase was hypothesized to enhance mating in the yellow peach moth, Conogethes punctiferalis. To test the hypothesis, the mating of moths under dim red, blue, and white lights during scotophase was observed. Under the dim red light, the enhancement of mating in C. punctiferalis was observed. In addition, the electroantennografic response of males against the female sex pheromone increased with red light treatment during scotophase. In an analysis of the differentially expressed genes in the antennae of males under red light and dark conditions, the expression levels of two odorant-binding protein (OBP) genes, CpunOBP2 and CpunPBP5, were up-regulated. Two genes were then expressed in Escherichia coli, and the recombinant proteins showed strong binding to female pheromone components in fluorescence-binding assays. Thus, the results of this study indicated that dim red light at night enhanced the mating of C. punctiferalis. One of the mechanisms for the enhancement was probably an increase in the antennal sensitivity of males to the female sex pheromone under red light that was caused by increases in the expression levels of pheromone-binding protein genes in male antennae.

Communication: Photoinduced Carbon Dioxide Binding with Surface-Functionalized Silicon Quantum Dots

2018 ◽  
Author(s):  
Oscar A. Douglas-Gallardo ◽  
Cristián Gabriel Sánchez ◽  
Esteban Vöhringer-Martinez
Keyword(s):  
Carbon Dioxide ◽  
Quantum Dots ◽  
Atmospheric Carbon Dioxide ◽  
Density Functional ◽  
Tight Binding ◽  
Carbon Dioxide Concentration ◽  
Research Area ◽  
Silicon Quantum Dots ◽  
Dependent Model ◽  
Photoinduced Charge

<div> <div> <div> <p>Nowadays, the search of efficient methods able to reduce the high atmospheric carbon dioxide concentration has turned into a very dynamic research area. Several environmental problems have been closely associated with the high atmospheric level of this greenhouse gas. Here, a novel system based on the use of surface-functionalized silicon quantum dots (sf -SiQDs) is theoretically proposed as a versatile device to bind carbon dioxide. Within this approach, carbon dioxide trapping is modulated by a photoinduced charge redistribution between the capping molecule and the silicon quantum dots (SiQDs). Chemical and electronic properties of the proposed SiQDs have been studied with Density Functional Theory (DFT) and Density Functional Tight-Binding (DFTB) approach along with a Time-Dependent model based on the DFTB (TD-DFTB) framework. To the best of our knowledge, this is the first report that proposes and explores the potential application of a versatile and friendly device based on the use of sf -SiQDs for photochemically activated carbon dioxide fixation. </p> </div> </div> </div>

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