Marine Biotechnology
Report: Algae
Supervisor: Dr. Tahir Ahmed Baig
Student Name: Arooj Fatima
Reg. No. 357689
Batch: UG-13
Atta-Ur-Rahman School of Applied Biosciences (ASAB)
National University of Science and Technology, Islamabad
May 2023
1. Algae:
Algae are photosynthetic organisms that can be found in a wide range of habitats, including
freshwater, saltwater, and moist soil. Algae play a crucial role in the aquatic ecosystem as they
provide food and oxygen for other organisms, including fish and aquatic plants.
2. Algal species in Shahdara:
In the Shahdara area of Islamabad, there are various types of algae that can be found in freshwater
bodies. Some of the common types of algae found in this area include:
Algae are photosynthetic organisms that can be found in a wide range of habitats, including.
1. Blue-green algae (Cyanobacteria) - These are a type of bacteria that can form large blooms
in freshwater bodies. They are often toxic and can pose a risk to human health and wildlife.
2. Green algae (Chlorophyta) - These are one of the most common types of algae found in
freshwater bodies. They can vary in size and shape and can be found in a wide range of
colors, including green, yellow, and brown.
3. Diatoms (Bacillariophyta) - These are a type of algae that are characterized by their unique
cell walls, which are made up of silica. They can be found in both freshwater and saltwater
bodies.
3. Sample Collection:
To observe the algae found in the Shahdara area of Islamabad, samples can be collected from the
freshwater bodies and observed under a microscope in the lab.
4. Observation under the Microscope:
Under the microscope, the blue-green algae can be identified by their characteristic shape, which
is often round or oval. Spirogyra was clearly observed.
Figure 1: Spirogyra observed under microscope.
Figure 2: Spirogyra Observed under microscope.
5. Spirogyra:
Spirogyra is a filamentous green alga that is commonly found in freshwater environments.
When observed under a microscope, several characteristics of its morphology and structure
can be observed:
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Filamentous structure: Spirogyra is composed of long, thin filaments that are usually
unbranched. These filaments can reach lengths of several centimeters and are made up
of cylindrical cells that are joined end-to-end.
Chloroplasts: The cells of Spirogyra contain numerous chloroplasts, which are
elongated and spiral-shaped. The chloroplasts contain the pigment chlorophyll, which
is essential for photosynthesis.
Nucleus: Each cell of Spirogyra contains a single nucleus, which is usually located near
the center of the cell. The nucleus is surrounded by a nuclear membrane and contains
the genetic material of the organism.
Cell wall: Spirogyra has a cell wall that is made up of cellulose. The cell wall provides
structural support for the organism and helps to maintain its shape.
Cytoplasmic streaming: When observed under a microscope, cytoplasmic streaming
can be seen in the cells of Spirogyra. This is the movement of the cytoplasm within the
cell, which is driven by tiny motor proteins.
Reproduction: Spirogyra reproduces asexually by fragmentation, where a filament
breaks apart into smaller pieces that can grow into new individuals. It can also
reproduce sexually, through the fusion of gametes.
6. Components Extraction:
Separating algae through cold ethanol is a common method used in the laboratory to extract
pigments from the cells. This process involves suspending the algae in cold ethanol and allowing
the pigments to dissolve into the solution. The ethanol is then centrifuged to separate the extracted
pigments from the cell debris and other impurities.
Figure 3: Components extraction
7. Spectrophotometry:
After extracting the pigments, one common method to quantify their concentration is through
spectrophotometry. Spectrophotometry is a technique that measures the amount of light absorbed
or transmitted by a sample at a specific wavelength. This method is often used to quantify the
concentration of pigments, such as chlorophyll, carotenoids, and phycobilins, in algae.
To perform spectrophotometry on the extracted pigments, a small amount of the solution is
transferred into a cuvette and the absorbance is measured using a spectrophotometer. The
absorbance is then compared to a standard curve of known pigment concentrations to determine
the pigment concentration of the sample.
The use of spectrophotometry to measure pigment concentration in algae can provide valuable
information about the physiological and ecological characteristics of the algae population. For
example, measuring the concentration of chlorophyll can provide insight into the photosynthetic
activity of the algae, while measuring the concentration of carotenoids can provide information on
the algae's adaptation to environmental stressors such as light and temperature.
Figure 4:Spectrophotometry readings
Figure 5:Spectrophoomery readings
8. Observations:
Two observations were recorded under two different wavelengths, 430nm and 662nm and 1.661
and 2.43 absorbances were observed.
A= abc
Absorption
a molar absorptivity constant different for every compound
B path length light traveling amount from cuvette, 1cm
c concentration
9. Results:
Overall, separating algae through cold ethanol and performing spectrophotometry on the extracted
pigments are valuable laboratory techniques for studying the characteristics and behavior of algae
populations in the Shahdara area of Islamabad. These methods can provide insights into the
physiological and ecological characteristics of the algae population, which can then be used to
develop targeted conservation strategies to protect and preserve the freshwater ecosystem in the
region.