2. Materials and methods

#### 2.1. Description of the study area and physiography of sampling sites

Bay of Bengal, a semi-enclosed tropical basin, is a part of the northern Indian Ocean and experiences seasonal changes in circulation and climate due to the monsoons. Visakhapatnam is a coastal city located on the eastern seaboard of India between Chennai and Calcutta (latitude 17�38'N and 17�45'N and longitude 83�16<sup>0</sup> E and 83�21<sup>0</sup> E) surrounded on three sides by the overlapping mountain ranges, and the South-eastern city is safeguarded by the Bay of Bengal. The South-west monsoon starts late in June and lasts till early October. North-east monsoon closely follows the South-west monsoon and extends till December. Fourteen sampling stations were selected along the Visakhapatnam offshore line and surface water samples were collected at the 30–40 M depth line of the sampling point. Sampling sites and global positioning systems of sampling locations was represented in Figure 1. The sampling stations between Bheemunipatnam (station 1) and Coastal Battery (station 7) cover the area like waste water of shrimp culture ponds, seafood processing centers, shrimp hatcheries, fish cages cultures and sewage outfalls enter into the coastline. The sampling stations between Harbor (station 8) and Pudimadaka (station 14) cover the areas where the effluents from the major power plants such as Nuclear Power Corporation of India limited and East Coast Energy limited enter on the coastal line.

40 km southward from the Visakhapatnam port), on the East Coast of India, was carried out at fortnightly intervals for a period of 2 years (February 2011 to January 2013) at 14 selected stations, along the Visakhapatnam offshore region. Samples were collected using clean plastic buckets from the surface sea water and transferred into 1 L amber color plastic bottles and stored in refrigerator until further analysis. The water sample free of zooplankton is filtered through Millipore (0.45 μm, 47 mm) filter paper and the pigments chlorophyll 'a', 'b' and 'c' are extracted

Checklist, Qualitative and Quantitative Analysis of Marine Microalgae from Offshore Visakhapatnam, Bay of…

http://dx.doi.org/10.5772/intechopen.75549

15

One hundred liters of sea surface water at each station was collected and filtered through coneshaped phytoplankton net of 20-μm mesh size, made by bolting silk and concentrated to

from the phytoplankton by using 90% acetone.

Figure 1. Map showing the sampling stations (1–14).

2.3. Collection of microalgae and identification

#### 2.2. Sample collection and estimation of chlorophyll

A mechanized boat was used to get into the sea for sample collection. Physico-chemical examination of sea surface waters in relation to microalgal abundance from Bheemunipatnam (approximately 23 km northward from the Visakhapatnam port) to Pudimadaka (approximately

Checklist, Qualitative and Quantitative Analysis of Marine Microalgae from Offshore Visakhapatnam, Bay of… http://dx.doi.org/10.5772/intechopen.75549 15

Figure 1. Map showing the sampling stations (1–14).

plant, petroleum refinery, fertilizer plant and a lead and zinc smelter are discharged into a North-Western arm of the inner harbor through surface drain known as Meghadri gedda and city's domestic sewage drains directly into the Northern arm of the inner harbor [3]. Microalgal abundance and distribution critically depending on various physical, chemical and biological factors [4] and their ability to assimilate sufficient carbon, nitrogen and phosphorous, as well as minor nutrients, to ensure replication. Alterations in species richness are mainly due to the

Multi-population microalgae and some native isolates i.e., Tetraselmis sp., Chlorella sp. were cultivated in open air pond in East cost of India proved the potential for biofuel production. Exploring microalgae diversity to find out the suitable season and spatial for microalgae isolation in Visakhapatnam coast since, the microalgae having wide application in biofuel and pharmaceutical. The research work from Andhra University, India revealed that Visakhapatnam coast is one of the potential sources for microalgae. Two years field work data from this study shows the relationship between the spatial and seasonal variations in Bay of Bengal, East Coast of India, and Visakhapatnam. Qualitative and quantitative analysis showed the feasibility to isolate the potential candidate strains for biofuels from the coastal water of

Bay of Bengal, a semi-enclosed tropical basin, is a part of the northern Indian Ocean and experiences seasonal changes in circulation and climate due to the monsoons. Visakhapatnam is a coastal city located on the eastern seaboard of India between Chennai and Calcutta (latitude 17�38'N and

tain ranges, and the South-eastern city is safeguarded by the Bay of Bengal. The South-west monsoon starts late in June and lasts till early October. North-east monsoon closely follows the South-west monsoon and extends till December. Fourteen sampling stations were selected along the Visakhapatnam offshore line and surface water samples were collected at the 30–40 M depth line of the sampling point. Sampling sites and global positioning systems of sampling locations was represented in Figure 1. The sampling stations between Bheemunipatnam (station 1) and Coastal Battery (station 7) cover the area like waste water of shrimp culture ponds, seafood processing centers, shrimp hatcheries, fish cages cultures and sewage outfalls enter into the coastline. The sampling stations between Harbor (station 8) and Pudimadaka (station 14) cover the areas where the effluents from the major power plants such as Nuclear Power Corporation of

A mechanized boat was used to get into the sea for sample collection. Physico-chemical examination of sea surface waters in relation to microalgal abundance from Bheemunipatnam (approximately 23 km northward from the Visakhapatnam port) to Pudimadaka (approximately

E) surrounded on three sides by the overlapping moun-

variability of abiotic factors, such as short-term climatic variations [5].

2.1. Description of the study area and physiography of sampling sites

E and 83�21<sup>0</sup>

India limited and East Coast Energy limited enter on the coastal line.

2.2. Sample collection and estimation of chlorophyll

Visakhapatnam.

14 Microalgal Biotechnology

2. Materials and methods

17�45'N and longitude 83�16<sup>0</sup>

40 km southward from the Visakhapatnam port), on the East Coast of India, was carried out at fortnightly intervals for a period of 2 years (February 2011 to January 2013) at 14 selected stations, along the Visakhapatnam offshore region. Samples were collected using clean plastic buckets from the surface sea water and transferred into 1 L amber color plastic bottles and stored in refrigerator until further analysis. The water sample free of zooplankton is filtered through Millipore (0.45 μm, 47 mm) filter paper and the pigments chlorophyll 'a', 'b' and 'c' are extracted from the phytoplankton by using 90% acetone.

#### 2.3. Collection of microalgae and identification

One hundred liters of sea surface water at each station was collected and filtered through coneshaped phytoplankton net of 20-μm mesh size, made by bolting silk and concentrated to 500 ml was transferred into pre-cleaned polyethylene bottles. The filtrate was preserved in 3% neutralized Lugol's iodine solution. All the water samples were filtered with 60-μm size zooplankton net in order to remove the zooplankton and debris. The filtrate was collected into five liters capacity Polyethylene Terephthalate (PET) jar and kept undisturbed for 2 days to achieve complete sedimentation. After sedimentation of phytoplankton, the supernatant solution was siphoned out to concentrate the volume to accurately about 100–200 ml. Concentrated samples were examined under bright field, dark ground illumination and phase contrast at 200, 400 and 1000 magnifications with the help of Axio scope A1 and Primo Vert (Carl Zeiss, Germany) microscopes. Identification of microalgae was done using an inverted research microscope based on standard keys [6–15] and current taxonomical details were been updated according to World Register of Marine Species and Algaebase (2015).
