Effect of photoperiod (PP) and photosynthetic photon flux intensity (PPFI) on nutrients consumption, growth and lipid profile of unusual microalga Picochlorum maculatum (PSDK01) in shrimp culture effluent

Microalgae have been known for broad spectrum of ecological and industrial applications. However, continuous mass culturing of microalgae is still a challenging task. In this context, studies on optimization of culturing conditions like photoperiod and light intensity on nutrients consumption are not uncommon. In the present study, we tried to evaluate the effect of different photoperiod (PP) and photosynthetic photon flux intensity (PPFI) on the nutrient consumption and algal growth of Picochlorum maculatum in shrimp culture effluent. The experiment lasted for 15 days at five different PP cycles (24:0, 18:06, 14:10, 10:14 and 6:18 h light:dark) and four PPFI (50, 100, 150 and 200 µmol m-2 s-1) at 28ºC temperature. Every five days the samples were analyzed and results showed that the PP of 18 h light and 6 h dark and 150 µmol m-2 s-1 of PPFI favouring the growth of P. maculatum with a maximum nutrients consumption (PO43+ 91%, NO3- 68%, NO2- 64%, NH3+ 77%), maximum growth (0.876±0.001 abs) and biomass production (9.93±0.19 g L−1) with highest yield of 9.2% total lipid. Among the photoperiod and photosynthetic photon flux intensity tested, 18:6 h light:dark and 150 µmol m-2 s-1 showed the highest nutrients removal and algal growth. This study strongly suggests that P. maculatum PSDK01 was a potential candidate for further commercial development in larger scale

Halophilic benthic diatom Amphora coffeaeformis—A potent biomarker for lipid and biomedical application

Biomarkers offer a powerful means to study life and its interaction with the environment. The evolutionary record of eukaryotic phytoplankton has been studied through fossils and molecular biomarkers, such as lipids and nucleic acids. Algal taxonomic groups containing carotenoids serve as age diagnostic biomarkers associated to photosynthetic pigments or fatty acids. Diatoms are known to thrive even in hypersaline conditions which are restricted to higher salinity. Results of this study have revealed the presence of a specific highly branched isoprenoid (HBI) compound, squalene (0.004 g) in the halophilic benthic diatom Amphora coffeaeformis which is considered to be the marker for hyper salinity. It also corresponds to the biomarker of oxidation processes.

Diagnostic whole body scan (pre‑therapy scan) in differentiated thyroid cancer: A single center community hospital experience.

OBJECTIVE: Diagnostic whole body scan (pre‑therapy scan) with either I‑123 or I‑131 (radioactive isotopes of iodine) is performed to assess the extent of thyroid cancer especially distant metastasis prior to administering the therapeutic dose of I‑131. Our aim of the following study was to determine the utility of the diagnostic pre‑therapy scan in the management of differentiated thyroid cancer. MATERIALS AND METHODS: It was a case‑control study carried out by retrospective chart review, of a randomly selected 100 patients with differentiated thyroid cancer who had followed in our community hospital over the course of 1 year. We collected data on multiple variables in the subjects ‑ including age, gender, pre‑operative size of the nodules, diagnosis, stage of the malignancy, size of the tumor, multifocality, lymphovascular invasion, dose of radioiodine used for remnant ablation, recurrence rates and persistence rates. Continuous variables were compared using the independent sample Mann‑Whitney U‑test whereas the Chi‑square test was used for nominal variables. RESULTS: The mean dose of radioactive iodine administered was 97.56 (±27.98) in the pre‑therapy scan group and it was 97.23 (±32.40) in the control group. There was no difference between the two groups (P ‑ 0.45). There was also no difference in the recurrence rates between the groups (P = 1.0). There was a trend toward a higher degree of persistent cancer in the group that had the pre‑therapy scans (P ‑ 0.086). CONCLUSION: Pre‑therapy scan may not affect the dose of radio‑iodine I‑131 used for remnant ablation of differentiated thyroid cancer and does not influence the recurrence rates. This was especially true with respect to I‑131 remnant ablation for low risk tumors.

Seasonal variations in physico-chemical characteristics of pond and ground water of Tiruchirapalli, India.

The aim of this study was to assess the open pond and groundwater quality of Tiruchirapalli city of Tamil Nadu, India. The groundwater quality viz., pH, electrical conductivity, total hardness, calcium ion, magnesium ion, chloride, carbonate, bicarbonate, inorganic nitrate, nitrite, phosphate, ammonia and reactive silicate were analysed with respect to various seasons and recorded in the range of 7.1 to 8.1, 97.67 to 533.67 mhos cm-1, 7.07 to 186 mg l-1, 4.67 and 112.0 mg l-1, 2.40 to 92.80 mg l-1, 15.23 to 661.73 mg l-1, 60 to 480 mg l-1, 22.7 to 544.9 mg l-1, 15.33 to 68.00 mg l-1, 0.001 to 0.480 mg l-1, 0.01 to 0.42 mg l-1, 0.02 to 0.75 mg l-1 and 1.1 to 2.96 mg l-1 respectively. The present findings concluded that the quality of ground waters can be considered suitable for human consumption. But the pond water available in and around Tiruchirappalli city was not fit for human usage, agricultural or industrial purposes.

Effect of temperature and algal food on egg production and hatching of copepod, Paracalanus parvus.

There are relatively few reports on the influence of environmental factors on the development and reproduction of calanoid copepods. In this study, we establish over the 12 days culture experiment at different temperature (18, 20, 25, 30 0C) and different algal cell densities 1000, 5000, 10,000, 20,000 cells ml-1. The results revealed that the high egg production (42.33 eggs female-1 day-1) and hatching rate (92.65%) was reported in the temperature of 25 0C. It is understood that the egg production of P.parvus clearly affected by temperature was supported by ANOVA value (F= 4.792909) while the egg production and hatching rate was found to be high as 53.5±4.94 eggs female-1 day-1, 96.26% respectively with 20,000 cells ml-1, The temperature of 25 0C and algal concentration was positively supported by ANOVA . The present study concluded that the temperature of 25 0C and food concentration of 20,000 cells ml-1 was found to be favorable water temperature and algal food concentration to obtain high fecundity and hatching success in copepod, P. parvus.

Copepod population in Vellar estuary, Parangipettai coast in relation to environmental conditions.

Distribution and abundance of copepods were studied in relation to environmental conditions at two different ecosystems viz: Neritic (Bay of Bengal) and estuarine (Vellar estuary) of Parangipettai coast from September, 1998 to August, 2000. Over the study period, total 85 species of copepods were reported. Among these, the calanoid copepods constituted the major component with 63.52% followed by cyclopoids (29.41%) and harpacticoids (7.05%). The copepods population density was found to be high (2, 53, 000 org l-1) in estuarine water, while the species diversity was higher (5.47) in neritic water. The observed spatio-temporal variations in the population density and species diversity of copepods were more related to the environmental state of respective study area.

Biochemical composition of wild copepods, Acartia spinicauda and Oithona similisfrom Parangipettai coastal waters in relation to environmental parameters.

Percentage composition of protein, lipid, carbohydrate and amino acids of copepods, Acartia spinicauda and Oithona similis collected from Parangipettai coastal waters were estimated following standard methodologies. Of the principal biochemical constituents, protein formed the major component followed by lipid and carbohydrate. Biochemical composition analysis of wild copepods indicated their nutritional rank. The ranges of protein, lipid and carbohydrate (%) contents (of A. spinicauda and O. similis) were 67.33-75.45; 12.42-16.58; 6.69-7.98 (Stn 1); 68.10-74.62; 12.65-17.81; 4.41-7.34 (Stn 2); 68.65-74.93; 14.55-17.69; 4.01-7.90 (Stn 3) and 59.53-69.61; 10.76-17.68; 3.43-6.59 (Stn 1); 62.39-67.09; 10.26-15.65; 3.78-5.85 (Stn 2) and 59.57-67.60; 9.89-15.44; 3.71-5.72 (Stn 3) respectively. Totally 16 amino acids were observed in these wild copepods, with threonine, glutamic acid, alanine, aspartic acid, serine, valine and methionine as the dominant ones. The minimum and maximum values of atmospheric and surface water temperatures (°C), salinity (‰), pH and dissolved oxygen (ml l-1) were 28.5-35; 28.7-34.2; 14.5-35.7; 7.4-8.6 and 3.0-7.2 respectively. The ranges (µM) of nitrate, nitrite, phosphate and silicate were 7.9-52.9; 0.6-9.6; 0.5-7.5 and 8.2-140.5 respectively. The results supported the view that protein may function as a metabolic reserve in copepods and that the availability of a constant supply of food may render large amount of lipid storage unnecessary in tropical copepods.