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Culturing of algal samples and isolation of pure cultures

The Algal samples were first transferred to the culture broth for the growth in BG-11 and
BBM media. Various methods were adopted such as spread plate, pour plate methods and

streak plate methods for the isolation of the desired algae (Toppo et al. 2014).
a) Spread Plate methods: In this method, 50 μl of algal culture from liquid medium was

directly spread over solidified autoclaved 1.5% agar media petri plates (BG-11/BBM
medium) with a help of sterilized L-shaped spreader. Isolation of pure algal strains was

carried out inside the laminar chamber by spreading of collected sample on to the autoclaved

agar plates. The algal colonies began to appear on the agar plate within 4-7 days.
b) Streaking method: Algal colonies were again streaked on to the fresh autoclaved agar plate

with the help of inoculating loop. Streaking process was repeated till the bacterial and fungal

contamination free unialgal colonies were recovered followed by transferring of algal
colonies to 75 mL of liquid media in 250 mL of Borosilicate conical flask. BBM (Annexure-

1) was used for green algae, BG-11 (Annexure-2) for the blue-green algae and diatoms.
c) Culture conditions: The cultures were illuminated with cool white fluorescent light with the

photo period of 14:10 light/dark period at 27˚C ± 1˚C.
d) Storage of Pure cultures: Isolated strains were stored in culture tubes in Algology culture

lab. The slant cultures were kept in slanting position with streaked area facing the light

source. Slants were labelled with name, place of collection, date and accession no. The
isolated liquid algal strains were preserved in 1% Lugol's solution and deposited at the

Lucknow Garden (LWG) Herbarium of CSIR-National Botanical Research Institute,
Lucknow, Uttar Pradesh, India (Accession No. CTR00051 to CTR00071).

Morphological Identification
Microscopic observation of algal samples was carried out by Leica DM 500 research

microscope connected with a computer having a digital image analyzer and software LAS EZ

1.8.0 taken with attached camera LEICA EC-3. The identification of freshwater green algae
was carried out using standard keys given by Prescott (1951); Philipose (1967); Desikachary

(1959); Karthick et al. (2013); Komarek and Anagnostidis (2005) and AlgaeBase (Guiry and

Guiry, 2021). (www.algaebase.org) was used for updating recent taxonomy.

RESULTS AND DISCUSSIONS
In the present study, morpho-taxonomic identification of freshwater algal isolates

from different collection sites of Jim Corbett National Park lead to altogether 21 strains.
Figure 2 depicts the no. of algal isolates under different classes. Morphological identifications

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