EurAsian Journal of BioSciences Eurasia J Biosci 14, 7101-7109 (2020) Combined effect of temperature, pH and salinity variation on the growth rate of Gloeocapsa sp. in batch culture method using Aiba and Ogawa medium Houria Bouazzara 1,2*, Farouk Benaceur 1,2, Rachid Chaibi 1,2, Ibtihel Boussebci 2, Laura Bruno 3 1 Department of Biology, Faculty of Sciences, University of Amar Telidji, 03000 Laghouat, ALGERIA 2 Laboratory of Biological and Agricultural Sciences (LSBA), Amar Thelidji university, Laghouat (UATL), 03000, ALGERIA 3 LBA-Laboratory of Biology of Algae, Dept. of Biology, University of Rome “Tor Vergata”, via Cracovia 1, 00133 Rome, ITALY *Corresponding author: [email protected] Abstract The development of cyanobacterial cultures is influenced by many environmental factors. In this analysis, the effect of pH, salinity and temperature on the growth of Gloeocapsa sp. isolated from Tadjmout dam, Laghouat province (Algeria) was investigated. The axenic cultures were maintained in sterilized culture media (Aiba and Ogawa). pH of the media was adjusted to 6, 7 and 10 using NaOH and HCl, while salinity was adjusted to 0.1%, 0.3%, 0.6% and 0.9% by varying the amount of NaCl in the media. The effect of temperature was studied by incubating the cultures at 25˚C, and 50˚C. The growth of Gloeocapsa sp. were determined by measuring its optical density and its chlorophyll-a content. Gloeocapsa sp. preferred alkaline pH. Low pH levels adversely affect the growth of Gloeocapsa sp. and substantially decreased at pH 6 despite sustained low biomass growth at pH 6 and 7. Gloeocapsa sp. has been able to grow at all salinities. The highest growth was shown at higher salt concentrations (0.6 and 0.9%). Gloeocapsa sp. showed best growth at 25°C but its growth at 50°C has decreased. These variables are useful for creating suitable culture conditions for promoting the growth of cyanobacteria and are also helpful in understanding their response to a variety of environmental factors. Keywords: cyanobacteria, Gloeocapsa sp., pH, temperature, salinity Bouazzara H, Benaceur F, Chaibi R, Boussebci I, Bruno L (2020) Combined effect of temperature, pH and salinity variation on the growth rate of Gloeocapsa sp. in batch culture method using Aiba and Ogawa medium. Eurasia J Biosci 14: 7101-7109. © 2020 Bouazzara et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License. INTRODUCTION (Gaysina et al. 2019). It is generally recognized that temperature is strongly linked to the growth rate of Cyanobacteria are the simplest and most abundant cyanobacteria (Mackey et al. 2013) and this association group of autotrophic prokaryotic living plants.They are differs among organisms. Salinity can influence the ancestral photoautotrophic, aerobic Gram-negative organism directly by influencing its physiology or bacteria and are able to produce their own food from indirectly by modifying the cell’s surroundings. inorganic matter (Mataloni and Komárek 2004, Gaysina Cyanobacteria are particularly susceptible to osmotic et al. 2019). In virtually any conceivable environment, stress, unable to respond to the development of organic cyanobacteria can be present throughout the term, and osmolytes and are seen to inhibit both nitrogen and in almost any terrestrial and aquatic ecosystem (Joshi et carbon fixation activity at increasing salt concentrations al. 2020).They are often present in terms of interaction (Rai and Rajashekhar 2016). Even so, salinity does not with other plants and animals, including lichens, influence all species to the same degree according to sponges, and protists (Konstantinou et al. 2018). their anatomical and genomic heterogeneity (Stal 2007) Cyanobacteria have also features such as water and thus the distribution of cyanobacterial species in keeping capability, short generation time, capacity to fix natural environments is not uniform. The adaptive ability atmospheric N2, tolerance to severe environments and of cyanobacteria to salinity had been the subject of they often function as influential phototrophic primary producers in natural environments, making Received: November 2019 cyanobacteria more specific and able to adapt to varying Accepted: April 2020 conditions in both natural and stressful ecosystems Printed: December 2020 7101 EurAsian Journal of BioSciences 14: 7101-7109 (2020) Bouazzara et al. several biochemical and ecological investigations MATERIALS AND METHODS (Rejmánková, Komárek and Komárková 2004). Besides, Gloeocapsa sp. was grown in batch culture in a cyanobacteria cultivation in a laboratory with appropriate closed system without any inlet or outlet streams as cultivation conditions can be accomplished by nutrients are prepared in a fixed volume of liquid media, understanding the eco-physiological needs of a given under sterile conditions at 25°C and 50°C with specific species. Hence, formulating an appropriate medium and pH (6, 7 and 10) and salinity (0.1, 0.3, 0.6 and 0.9%) improving cultural environments is a prerequisite for conditions. The sample was pre-cultivated in batch achieving high production of biomass. Thus, culture (Aiba and Ogawa medium); A closed microbial physiological variables of temperature, pH, salinity, or culture system with a particular nutrient, temperature, chemical factors such as media composition influence strain, aeration and other environmental conditions to the growth rate, physiological state, and biochemical maximize growth. As nutrients are not added or waste composition of cyanobacteria under conditions of culture products eliminated during incubation, only a finite (Lee and Kim 2002). Measurement of chlorophyll-a can amount of life cycles can be achieved before nutrients be used to control their physiological status and growth. are absorbed and growth ceases; for 10 days (about 20 Cyanobacteria demonstrate high adaptability to pH and generations) to obtain adapted cultures. Chlorophyll-a salinity, but mass cultivation requires optimum and growth levels have been calculated as mentioned conditions (Nagle et al. 2010). Biochemical and later. The experiments were repeated twice-using nutritional components of productive species such as independent cultures. Spirulina platensis are recognized as screening for growth characteristics (Soni et al. 2012) due to their Study area The underground dam of Tadjmout in the industrial use, but much consideration has not been municipality of Tadjemout, Laghouat province, which is given to the characterization of other cyanobacterial 250 meters long, providing an annual storage capacity organisms. Freshwater microalgae have been found to 3 be an effective source of protein, lipid, carbohydrates, of 4.7 million m , with a flow rate of 140 liters per second able to irrigate 250 hectares of orchards and 600 and vitamins, and are therefore used in aquaculture hectares of Tadjemout pilot farm. It is situated at the studies.It has been shown that salinity and pH induce the nutritional properties characteristic of the latitude of 33°54.100’ north and longitude of phytoplankton. The characterization of such species in 002°28.401’east and at an altitude of 907 m above the order to achieve high quality and quantity of biomass in sea level. The seasonal patterns of climatic variables in the month of February 2020 was typical for the region, laboratory environment, in order to allow effective use of them, has been little investigated. Recently, several and was characterized by dry weather. The study region research paper have given particular attention on impact has a desert climate, the rains are practically non- of temperature, salinity and pH on cyanobacteria growth, existent. The maximum temperature was 18°C and the minimum was 12°C; precipitation was 00 mm. but have no report on the effect of combined salinity, pH Therefore, wind was 0 km/h and cloud cover was 25% and temperature on growth rate of Cyanobacteria on freshwater ecosystem (Schubert et al. 1993, Rakko and humidity 26% (ONM, 2020). Seppälä 2014, Muruga et al. 2014, Shruthi and Sampling of water Rajashekhar 2014, Silveira and Odebrecht 2019, Sen Water samples were collected from locations varying 2020). Gloeocapsa sp. is a Cyanobacteria belonging to from colorless, bluish and brownish to green of specific the Eubacteria kingdom, phylum Cyanobacteria classes water coloration. The research was conducted in the Cyanophyceae, order Chroococcales, family month of February 2020 at the dam of Tadjmout. Microcystaceae with some features. The shape of genus Approximately 300 mL of sample water were collected Gloeocapsa is commonly spherical between 1 and 17 in three sterile 150 mL bottles from each location. The µm in diameter, aggregated in a macroscopic samples were transported to the laboratory in a cool box mucilaginous, amorphous mass that colonizes wet stony and kept in waiting for analysis at 4°C. Water quality was substrates and, less often tree bark or aquatic determined by measuring the temperature, pH, environments (metaphyton or plankton). Gacheva et al. dissolved oxygen, conductivity, salinity, total dissolved (2013) demonstrate the ability of the genus Gloeocapsa solid and also by analyzing chlorophyll-a, where to grow in a wide temperature range (15°C–40°C). In this temperature was 17.3°C, pH of the water was slightly study the response of Gloeocapsa sp isolated from alkaline with a value of 7.98 conductivity, and TDS were Tadjmout dam water, south of Algeria to different 2224 and 1108 μs cm-1 respectively. Salinity with a value variation