post lab discussion: exp 8

Question 1

phytochemicals is also known as

Answer 1

“plant chemicals”

Question 2

natural bioactive compounds found on different parts of a plant

Answer 2

Phytochemicals
(leaves, roots, stems, flowers)

Question 3

Organic compounds that are not directly involved in a plant’s growth, reproduction, and development

Answer 3

Secondary Metabolites
- it produces compounds that plants does not need for it to produce and grow

Question 4

what are the 4 major classes of secondary metabolites

Answer 4

o terpenes
o phenolics
o polyketides
o alkaloids

Question 5

these are based on isoprene molecule

Answer 5

terpenes
- 5 carbon organic compund with 2 saturations

• essential oils, spices, flavorings
  (e.g. citronella, camphor, eucalyptus)

Question 6

oxygenated derivatives of terpenes

Answer 6

Terpenoids

• contain, -OH, -C=O
• unsaturated

Question 7

Flavonoids are derived from

Answer 7

Phe and acetate metabolism
- contain flavan (C6-C3-C6) skeleton

Question 8

basic nitrogenated compounds

Answer 8

alkaloids
* largest class of secondary metabolites
- analgesics (pain-killing compounds), narcotics (drugs that induce sleep), CNS stimulants (accelerate brain activity like increase alertness, attention, energy), antimicrobials (inhibits microorgansim growth)
(example: morphine)

Question 9

glycosides

Answer 9

sugar (glycone) + non-sugar (aglycone) molecule via a glycosidic bond

(example: salicin)

Question 10

steroid/triterpenoid glycosides

Answer 10

saponins
- used as detergent
- forms froth when agitated in aq soln
(triterpenic aglycone/ steroidic aglycone)

Question 11

these are polyphenols

Answer 11

tannins
* can react with and precipitate proteins
* tanning agent

Question 12

types of tannins

Answer 12

• Hydrolyzable
  – can be hydrolyzed by enzymes; phenolic acid+glucose via ester linkage
• Condensed
• derivatives of flavonoids

Question 13

why should the samples be dried

Answer 13

Samples are dried to reduce water content, so that the plant can be stored
* Plant has ~60-80% moisture
* Must be dried right after harvest to avoid deterioration

Question 14

what are the drying methods of sample collection

Answer 14

o Natural Drying (Sun-drying)
o Artificial
- cold-air drying (use of fans that blow unheated hair)
- warm-air drying

Question 15

what is an disadvantage of natural drying

Answer 15

Plant can be damaged by the weather
- when it rains, can rehydrate the plants
- if too hot, UV detoriation and we dont want it destroy

Question 16

what happens after the pant samples were ground to fine particels

Answer 16

add 95% ethanol immersing the plant sample
obtaining the ethanolic extract after several days
obtain the ethanolic extract using rotary evaporator

Question 17

what are the primary metabolites of plants

Answer 17

nucleic acids
carbs
proteins
lipids