scholarly journals Phaeodactylum Trıcornutum Kültürlerinde Biyomas Tahmini

Author(s):  
Burcu Ak ◽  
Gökhan Tamer Kayaalp ◽  
Oya Işık ◽  
Melis Çelik Güney

Phaeodactylum tricornutum is the microalgae that is known to produce lipid. In this study, it was aimed to estimate the microalgae Phaeodactylum tricornutum dry matter cultured in the conditions of nitrogen deficiency as a stress factor, in outdoor, in photo bioreactors, by using multiple regression analysis method. In this study, diatom Phaeodactylum tricornutum (Bohlin) was cultured medium of which N was reduced by 50% and with 20% inoculation ratio. The light intensity, temperature, optical density and chlorophyll a, were measured daily. The mathematical model was formed for control group and 50 % of the N applied to the group using optical density, temperature, light intensity, chlorophyll a and without chlorophyll a. The regression equation of control group was estimated. The R2 value of control group was found 95.1% and statistically significant. Then, the regression equation was estimated for control group without chlorophyll a. The R2 value of this equation was found 94.0% and statistically significant. And then, the regression equation was estimated in 50% nitrogen. The R2 value of control group was found 92.4% and statistically significant. Finally, the regression equation was estimated in 50% nitrogen deficiency without chlorophyll a. The R2 value of this equation was found 91.7% and statistically significant.

Author(s):  
Leyla USLU

In the study, Porphyridium cruentum was cultured under laboratory conditions at 20±2°C, 16:8 (light:dark) photoperiod and continuous aeration to different salinity (20‰, 30‰, 40‰) and two different light intensities (37 µmol m-2s-1 photon and 110 µmol m-2s-1 photon) and growth was determined. Dry matter, optical density and chlorophyll a parameter were used to determine growth. The best growth was determined in culture with a salinity of 30‰ at 110 µmol m-2s-1 photon light intensity. In this group, the optical density (OD) was 1.504±0.003 and the dry matter amount was 1.327gl-1. In the case of 37µmol µmol m-2s-1 photon light intensity, the optical density values were found to be similar in groups with 30‰ and 50‰ salinity and were found to be 1.234±0.004 and 1.215±0.002, respectively. The amounts of dry matter were also similar; 1.168gl-1 and 1.159gl-1, respectively. While the lowest growth was in the culture at 37 µmol m-2s-1 photon light intensity and 20‰ salinity. The optical density obtained on the last day of this group was 1.165±0.004 and the dry matter amount was determined as 0.986gl-1. The amount of chlorophyll a was determined in the cultured groups at the best 37 µmol m-2s-1 photon light intensity.


Author(s):  
Leyla Uslu ◽  
Gökhan Tamer Kayaalp ◽  
Oya Işık ◽  
Burcu Ak Çimen ◽  
Melis Çelik Güney

Isochrysis affinis galbana is a single-cell marine species. Isochrysis affinis galbana is used as a live feed source in aquaculture because it contains high amount of long chain unsaturated fatty acids (PUFA), especially in the feeding of larvae of bivalves, Phaeodactylum tricornutum is a diatom species of pennate with oval and fusiform cell forms. Phaeodactylum tricornutum contains 30-45% long chain unsaturated fatty acids (PUFA) of which 20-40% is eicosapentaenoic acid (EPA). And the diatom which is thought to be sources of essential fatty acids and carotenoids (fucoxanthin) is used in the feeding of animal in aquaculture and human. The aim of this study was to estimate the dry matter content of cultured Isochrysis affinis galbana and Phaeodactylum tricornutum by using multiple regression analysis method. Species were cultured in the laboratory conditions with a control group with 20% inoculation rate in F/2 medium and 50% nitrogen deficient medium. During the experiment, optical density, dry matter and chlorophyll a were measured daily. A mathematical model was developed using optic density and chlorophyll a data of the control group and in the group where 50% of the nitrogen was eliminated. Significance test of these models, R2 and MSE were found.


1983 ◽  
Vol 32 (1) ◽  
pp. 91-98
Author(s):  
Gilda Schmidt

The effect of high nitrate concentration and light intensity on chlorophyll-a synthesis, cell number and nitrate assimilation on P. tJt¿coh,nuutum culture, was determined. Growth and uptake rates were determined as a function of nitrate concentration ranging from 0.40 to 35.40 µg/l. The Ks showed high values, when compared with those obtained with lower nitrate concentration. The percentual variation of Ks was greater than that of Vmax.


2021 ◽  
Vol 9 (1) ◽  
Author(s):  
Gopal Keerthipriya ◽  
Nesamani Ravikumar ◽  
Sekar Mahalaxmi

Abstract Introduction Bacterial adherence to restorative materials such as composite resin is one of the aetiology of secondary caries. This study evaluated the antibacterial efficacy of fifth generation bonding agent (BA) modified with nisin, against Streptococcus mutans based on its growth, adherence and membrane integrity. Methods Adhesive eluents of the experimental bonding agents were obtained using 250 μl Brain Heart Infusion (BHI) broth and the groups were control (BA with 0% Nisin), bonding agent with 1 wt% (NBA 1) and 5 wt% nisin (NBA 5). To this, 10 μl S. mutans culture was added and incubated at 37 °C. Bacterial growth was estimated by changes in optical density using spectrophotometer every 20 min for 2 h. The results were statistically analysed using one way ANOVA followed by Tukey Post Hoc test. For adherence and membrane integrity test, 10 μl of BHI supplemented with 1% sucrose and 50 μl of bacterial suspension were inoculated onto the cured specimens, and incubated for 4 h. After rinsing, 1 ml of Live/Dead BacLight bacterial viability stain was added and incubated in the dark for 15 min and observed under confocal laser scanning microscope (CLSM) for intact (green/live) and damaged (red/dead) bacterial membranes. Results Mean optical density was significantly higher in control group at all time intervals with maximum value at 2 h (0.83 ± 0.008), while there was a concentration dependant reduction in bacterial growth with the NBA groups (0.50 ± 0.007). Correspondingly, the NBA groups showed higher amount of dead than live bacteria, while live bacteria were predominant in the control group. Significance Addition of an antibacterial agent nisin in dentin bonding agent may render the resin dentin interface more resistant to bacterial penetration, and adherence of cariogenic bacteria like S. mutans.


Forests ◽  
2019 ◽  
Vol 11 (1) ◽  
pp. 21
Author(s):  
Zhong-sheng He ◽  
Rong Tang ◽  
Meng-jia Li ◽  
Meng-ran Jin ◽  
Cong Xin ◽  
...  

Light is a major environmental factor limiting the growth and survival of plants. The heterogeneity of the light environment after gap formation in forest influences the leaf chlorophyll contents, net photosynthetic rate (Pn), and chlorophyll fluorescence, thus influencing the growth and regeneration of Castanopsis kawakamii seedlings. The aim of this study was to explore the effects of weak light on the photosynthetic physiology of C. kawakamii seedlings in forest gaps and non-gaps. The results showed that (1) the contents of chlorophyll a (Chl-a), chlorophyll b (Chl-b), and total chlorophyll (Chl-T) in forest gaps were lower than in non-gaps. Seedlings tended to increase chlorophyll content to absorb light energy to adapt to low light intensity in non-gap environments. (2) The Pn values of C. kawakamii seedlings in forest gaps were significantly higher than in non-gaps, and forest gaps could improve the seedlings’ photosynthetic capacity. (3) The C. kawakamii seedlings in forest gaps were more sensitive to weak light and control group treatment, especially the tall seedlings, indicating that seedlings require more light to satisfy their growth needs in the winter. The seedlings in non-gaps demonstrated better adaptability to low light intensity. The light intensity was not adequate in weak light conditions and limited seedling growth. We suggest that partial forest selection cutting could improve light intensity in non-gaps, thus promoting seedling growth and regeneration of C. kawakamii more effectively in this forest.


1990 ◽  
Vol 41 (6) ◽  
pp. 1093 ◽  
Author(s):  
JL Wheeler ◽  
C Mulcahy ◽  
JJ Walcott ◽  
GG Rapp

The effect of seven factors, namely genotype, plant maturity, nitrogen fertilizer, phosphorus fertilizer, water stress, light intensity and temperature, on the hydrogen cyanide potential (HCNp) of forage sorghum was studied in three pot experiments. Fivefold differences occurred between genotypes in HCNp, with a breeder's line, X45106, selected for low HCNp having a maximum of 520 mg HCN kg-1 DM (dry matter) compared with 2300 and 2450 mg kg-1 DM for cvs Zulu and Silk respectively. In X45 106, HCNp (mg HCN kg-1 DM) declined curvilinearly with age d (days from sowing) (HCNp=8460- 320d+ 3.1d2) and linearly in Silk (HCNp = 9020 - 110d), but the decline in Zulu was not statistically significant. Nitrogen (equivalent to 200 kg ha-1 of N) increased HCN, (P< 0.001), but more so in full light (100 mg kg-1 compared with 1430 mg kg-1) than in 50% shade (190 mg kg-1 compared with 690 mg kg-1). In one experiment, acute water stress appeared to reduce HCNp, but this was confounded with the strong decline due to aging. In another study, acute water stress had no effect on HCNp. Neither the application of superphosphate nor change in light intensity, nor change in temperature had a direct significant effect on HCNp in these studies. Breeding and selection for low HCNp appears a promising approach to ensuring that sorghum plants will provide non-toxic forage from an early stage of growth.


1977 ◽  
Vol 57 (2) ◽  
pp. 279-288 ◽  
Author(s):  
S. O. THORLACIUS

Digestibility and intake of diets containing 8, 28, 48 or 68% ground wheat straw plus ground crested wheatgrass and rapeseed meal, and diets containing 33, 48, 63 and 78% ground crested wheatgrass plus barley and rapeseed meal was measured with four yearling wethers per diet. Digestible energy (DE) content ranged from 2.07 to 2.95 kcal/g dry matter (DM) and dry matter digestibility (DMD) (%) from 48.7 to 71.1%. Regression of DE intake y (kcal/w0.75kg/d) on DE content (x) was curvilinear; y = −2,133 + 1,626x − 277.9x2, r = 0.996, P < 0.01, SE = ± 7.3. There was also a curvilinear relationship between diet density, as fed, (x) g (DM)/ml and DMD (%), y = 9.057 + 364.1x − 530.0x2, r = 0.970, P < 0.01, SE = ± 2.4. A linear regression equation was calculated over the DE range (2.07–2.52) for which there was an obvious increase in DE intake with increasing diet DE content; y = −700.6 + 361x, r = 0.994, P < 0.01, SE = ± 9.4, y = DE intake (kcal/w0.75kg/d), x = DE [kcal/g (DM)]. Using this regression equation and assuming a linear increase in DE intake with increase in diet DE content up to a point at which the apparent energy demand of the animal is satisfied gave a more accurate prediction of DE intake than when the curvilinear regression equation, y = −2,133 + 1,626x − 277.9x2, was used empirically. Accuracy of the prediction was further improved by expressing DE/unit ration volume instead of per unit DM. The sheep used in the present experiments had an apparent energy demand of 230 kcal/w0.75kg/day which was met at diet DE contents above 0.48 kcal/ml or 2.6 kcal/g (DM). There was a high correlation between in vivo DE content of the diet, y [kcal/g (DM)] and in vitro (x) digestible organic matter content, x, (%), r = 0.991, P < 0.01, y = 0.38 + 0.037x, SE = ± 0.04.


1987 ◽  
Vol 23 (2) ◽  
pp. 193-200 ◽  
Author(s):  
J. M. O. Eze

SummaryThe growth of Amaranthus hybridus under different daylight intensities was assessed in terms of physical, morphological and biochemical parameters. Maximum growth in many respects was achieved at about 70% of full daylight. However, full daylight favoured chlorophyll stability and maximum accumulation of total dry matter, carbohydrate, chlorophyll and ascorbic acid. The leaf area ratio increased uniformly with decrease in light intensity. Ageing was accelerated by full daylight. Reduced light intensity reduced dry matter accumulation in the roots more than in the stems or leaves.


Author(s):  
В. Волошин ◽  
Н. Морозков

По результатам научных исследований, выполненных за ряд лет в растениеводстве и животноводстве, показана целесообразность интродукции в кормопроизводство Пермского края новой многолетней бобовой культуры эспарцета песчаного. По четырёхлетним наблюдениям (2012 2015 годы) в полевых опытах культура не уступала по урожайности кормовой массы традиционному для региона клеверу луговому, а по концентрации обменной энергии и сырого протеина в сухом веществе была на уровне клевера лугового и люцерны изменчивой, но в разы превосходила их по содержанию сахара. Сенаж это единственный вид зимнего корма, максимально сохраняющий обменную энергию, протеин, сахар, каротин, достаточно концентрированный, чтобы обеспечивать потребности высокопродуктивных животных. В 2018 году на Лобановском молочном комплексе ООО Русь в Пермском районе Пермского края были проведены научнохозяйственный и физиологический опыты по скармливанию сенажа из эспарцета песчаного голштинизированным коровам чёрнопёстрой породы. При использовании сенажа из эспарцета песчаного животные в сутки потребляли сухого вещества на 2,3 3,9 кг на голову больше по сравнению с группой, где в рационе было сено (контроль). В результате использования сенажа из эспарцета песчаного переваримость сухого вещества рациона у опытных групп животных была выше на 2,55 5,80 по сравнению с контрольной органического вещества на 2,54 4,14 . За учётный период научнохозяйственного опыта (120 дней) от коров опытных групп получено по 399327,2 и 414431,9 кг молока, что со средней степенью достоверности выше продуктивности животных контрольной группы (391045,4). По содержанию молочного жира и молочного белка преимущество достоверно также было за опытными группами. Затраты корма на 1 кг молока составили в контроле 0,74 энергетических корм. ед. (ЭКЕ), в опытных группах 0,71 и 0,69 ЭКЕ. Hungarian sainfoin was shown to be an effective perennial legume crop in the forage production of the Perm Territory. For 4 years (2012 2015) this crop produced forage mass, exchange energy and crude protein comparable to the ones of red clover and bastard alfalfa but exceeded them significantly in carbohydrate content. Haylage is the only type of winter forage that has sufficient concentrations of exchange energy, protein, carbohydrates and carotene, satisfying needs of highproductive livestock in nutrients. Haylage from Hungarian sainfoin was fed to Holstein BlackandWhite cows in the frame of experiments conducted in 2018. Cows consumed 2.3 3.9 kg more of dry matter (DM) with the haylage, compared to hay (control). Digestibilities of DM and organic matter were 2.55 5.80 and 2.54 4.14 higher than in the control group, respectively. For 120 days the experimental groups produced 3993 27.2 and 4144 31.9 kg of milk versus 3910 45.4 kg of the control one. The former also exceeded the latter in milk fat and protein contents. Fodder costs per 1 kg of milk amounted to 0.74 energy feed units in the control and 0.71 and 0.69 energy feed units in the experimental groups.


1987 ◽  
Vol 252 (5) ◽  
pp. H1031-H1040 ◽  
Author(s):  
M. L. Ellsworth ◽  
R. N. Pittman ◽  
C. G. Ellis

We present a computer-aided videodensitometric method for the determination of oxygen saturation in red blood cells flowing through capillaries of the hamster cheek pouch retractor muscle. The optical density (OD) of red blood cells is determined at two wavelengths. At the first, 431 nm, there is a maximum difference between absorption by oxygen deoxyhemoglobin. At the second, 420 nm, absorption is equal for the two absorbing species (isosbestic wavelength). In capillaries of the retractor muscle a relationship between oxygen saturation (S) and the following OD ratio was obtained as S = -1.71 (OD431/OD420) + 2.20. The error (95% confidence interval) in oxygen saturation associated with a determination of the OD ratio is estimated to be +/- 4.8%. The computerization of the method employs a frame-by-frame analysis of the light intensity over a selected capillary segment. The light intensity waveform along the segment is digitized and the minimum (I) and maximum (I0) light intensities are used to compute an optical density (OD = log10 [I0/I]). These minimum and maximum intensities correspond to the presence and absence of a red blood cell, respectively. The method permits the off-line analysis of videotaped scenes and provides a means of assessing the extent of temporal and spatial heterogeneity of oxygen saturation in selected capillary networks. The method has been developed for use in capillaries in transilluminated striated muscle but should be generally applicable to the measurement of capillary oxygen saturation in other tissues.


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