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Annona squamosa L is a multipurpose tree with edible fruits and is a source of the medicinal and industrial products. It is used as an antioxidant, antidiabetics, hepatoprotective, cytotoxic, genetoxic, anti tumor, anti lice agent etc.Annona squamosa
sensorDeskripsi lengkap
laporan obervasi mikrobiologi PEMANFAATAN LIMBAH SABUT KELAPA DENGAN PEMAKAIAN EFFECTIVE MICROORGANISM (EM4) SEBAGAI PRODUK PUPUK ORGANIK CAIR (POC)Deskripsi lengkap
Topic : The effect of humidity on the growth of microorganisms Aim
: To study the effect of humidity on the growth of microorganism
Hypothesis : Microorganisms grow rapidly in moist condition Variables
: a) Manipulated variable: The presence of water b) Responding variable : The growth of microorganism c) Constant variable : same type of bread
Materials and apparatus : 2 pieces of bread, water, clear plastic bag Procedure
:
1) A piece of bread is sprinkled with water and placed in a clear plastic bag labeled A. 2) The other piece is kept dry and placed in the clear plastic bag labeled B. 3) Both plastic bags are kept in a dark place for two days. 4) The result of the experiment is observed and recorded in the table below. Results
:
Presence of moisture A: Moist bread B : Dry bread
The growth of microorganism (mucor) A lot of microorganism (mucor) A few microorganism ( mucor)
Discussions : 1. After two days the mucor grows on the moist bread because of the presence of water, but no mucor grows on the dry bread. 2. Mucor needs water to grow. 3. Hypothesis is accepted.
Conclusion
: Microorganisms grow rapidly in moist condition.
Topic :
Effect of temperature on the growth of bacteria.
Aim
: To study the effect of temperature on the growth of bacteria
Hypothesis : bacteria grows and reproduce quickly at room temperature but not at low or high temperature. Variables
: a) Manipulated variables: temperature b) Responding variables : Number of bacterial colonies c) Constant variables
: Volume of bacterial culture
Material s and apparatus : sterile nutrient agar, bacteria culture ( bacillus subtilis), sterile petri dishes and lids, syringes, cellophane tape, refrigerator and oven. Procedure:
:
1. Three sterile petri dishes containing sterile nutrient agar are prepared and labeled A, B and c respectively. 2. 1cm3 of bacteria culture solution is added onto the agar surface in each petri dish by using a syringe. 3. The petri dishes are covered with their lids and sealed using cellophane tape. 4. The petri dishes are inverted and placed as below: a) Petri dish A in a refrigerator set at 5⁰C b) Petri dish B at room temperature (30⁰C)
c) Petri dish C in an oven at 80⁰C
5. The petri dishes are kept for two days. 6. The number of bacterial colonies are observed and recorded.
Results
: Temperature (⁰C)
Number of bacterial colonies
5
None
30
Many
80
None
Discussions : 1. Microorganisms grow rapidly at room temperature 2. Temperatures that are too cold or too hot are not suitable for bacterial growth. 3. Hypothesis is accepted.
Conclusion : Bacteria grows and reproduce quickly at room temperature but do not grow at temperatures that are too high or too low.
Topic : the effect of pH on the growth of microorganisms
Aim : To study the relationship between pH value and the growth of microorganisms.
Hypothesis : Neutral condition is suitable for the growth of microorganisms Variables
: a) Manipulated variables : pH value b) Responding variables : Cloudiness of the nutrient broth c) Constant variable : Volume of nutrient broth
1. Three test tubes labeled A, B and C are prepared. 2. 5cm3 of nutrient broth is poured into each test tubes. 3. 1cm3 of bacteria culture is added into each test tubes. 4. 1cm3 of hydrocloric acid, 1cm3 of sodium hydroxide solution , 1cm3 of distilled water are added by using syringes into the nutrient broth in test tubes A, B and C respectively. 5. The test tubes A, B and C are plugged with cotton wool. 6. The three test tubes are kept in the dark cupboard for 2 days. 7. The content of the test tubes are observed and recorded.
Observation
:
Test tubes
Condition of the nutrient agar
Cloudiness of the nutrient broth
A
Acidic
Slightly cloudy
B
Alkaline
Slightly cloudy
C
Neutral
Very cloudy
Discussions : 1. After two days, nutrient broth in test tubes A and B becomes only slightly cloudy because microorganisms do not grow well in acidic and alkaline conditions. 2. In test tube C, the nutrient broth becomes very cloudy because microorganisms grow rapidly in neutral condition. 3. Hypothesis is accepted. Conclusion : Neutral condition is the most suitable pH for the growth of microorganisms.
