Medicinal Plants: Basic Knowledge and Precautions

This article provides basic knowledge about medicinal plants, including their structure, characteristics and some additional information.

Note:

This article is for informational purposes only. To use herbs safely and effectively, consult a healthcare professional.

1. Plant Structure:

• Root:
  • Primary structure: Root hair layer, primary cortex, central cylinder.
  • Tuberous root: Formed from the main root, e.g. carrot.
  • Adventitious root: Grows from the stem node to help the plant cling to other plants or trellises.
  • Pneumatophores: Found in many plants living in swamps, helping the plant absorb oxygen.
  • Fibrous root: The main root branches into many rootlets, e.g. rice plant.
  • Tap root: The main root develops strongly, growing deep into the soil, e.g. grapefruit tree.
• Stem:
  • Primary structure: Epidermis, cortex, central cylinder.
  • Secondary structure: Phellogen, phellem, endodermis, phloem, xylem.
  • Tuber: Formed from the main stem, e.g. potato.
  • Bulb: Formed from leaf sheaths stacked on top of each other, e.g. onion.
  • Rhizome: An underground stem growing horizontally, e.g. ginger.
  • Stolon: Stem growing horizontally above ground, e.g. cucumber.
  • Vine: Stem climbing up using tendrils or hooks, e.g. pumpkin.
• Leaf:
  • Leaf structure: Leaf blade, petiole, leaf sheath, leaf veins.
  • Parallel venation: Leaves have veins running parallel to each other, commonly seen in monocots.
  • Net venation: Leaves have veins branching to form a network, commonly seen in dicots.
  • Simple leaf: Leaf with one blade, e.g. orange leaf.
  • Compound leaf: Leaf with multiple blades, e.g. tamarind leaf.
• Flower:
  • Flower structure: Sepals, petals, stamens, pistil.
  • Unisexual flower: Flower has only stamens or pistil.
  • Bisexual flower: Flower has both stamens and pistil.
  • Regular flower: Petals have the same shape and size.
  • Irregular flower: Petals have different shapes and sizes.
  • Inflorescence: Includes many flowers growing together on a common axis.
  • Inflorescence type: Raceme, spike, umbel, cyme, head…
• Fruit:
  • Fruit structure: Pericarp, flesh, seed.
  • Simple fruit: Fruit formed from one flower.
  • Aggregate fruit: Fruit formed from many flowers.
  • Dry fruit: Fruit with hard skin, dry flesh.
  • Berry: Fruit with soft skin, soft flesh.
  • Drupe: Fruit with a hard seed covered by a hard shell.
  • Legume: Fruit with hard skin, splitting along a suture.

2. Plant Tissues:

• Meristematic tissue: Tissue with the ability to divide to produce new cells.
  • Apical meristem: Located at the tip of the stem and root, helping the stem and root to grow in length.
  • Lateral meristem: Located in the cortex and central cylinder, helping the stem and root to grow in width.
• Parenchyma tissue: Tissue consisting of thin-walled cells, with the function of connecting other tissues, storing nutrients.
  • Assimilation parenchyma: Containing many chloroplasts, helping plants photosynthesize.
  • Storage parenchyma: Containing many starch, helping plants store energy.
• Collenchyma tissue: Tissue consisting of thick-walled cells, with the function of supporting the plant.
  • Angular collenchyma: Thick tissue concentrated at the corners of the stem, e.g. plants in the mint family.
  • Aerenchyma: Thick tissue with air-filled intercellular spaces, e.g. duckweed.
• Sclerenchyma tissue: Tissue consisting of thick-walled, lignified cells, with the function of protecting and supporting the plant.
• Secretory tissue: Tissue consisting of cells that secrete nutrients, toxins…
  • Glandular trichomes: Formed by one or many cells that secrete substances, e.g. essential oil-secreting trichomes.
  • Secretory sacs: Chambers containing secreted substances, e.g. latex sacs.
  • Secretory ducts: Conduits containing secreted substances, e.g. essential oil ducts.
• Vascular tissue: Tissue consisting of specialized cells with the function of transporting nutrients in the plant.
  • Phloem: Transports organic substances from the leaves to other parts of the plant.
  • Xylem: Transports water and minerals from the roots to other parts of the plant.

3. Characteristics of Some Plant Families:

• Mint family (Lamiaceae): Plants have square stems, opposite leaves, irregular flowers, 2 prominent stamens, fragrant essential oils. Example: mint, perilla, basil…
• Aster family (Asteraceae): Plants have capitulum flowers, with reduced calyx and often developing into a pappus, small fruits, fragrant essential oils. Example: marigold, sunflower, dandelion…
• Gourd family (Cucurbitaceae): Plants have creeping or climbing stems, large berries, often with tendrils. Example: pumpkin, cucumber, squash…
• Carrot family (Apiaceae): Plants are herbaceous, stems often hollow, compound leaves with sheaths, compound umbels of flowers, fragrant essential oils. Example: celery, parsley, fennel…
• Pea family (Fabaceae): Plants have legumes, racemes of flowers, compound leaves often with stipules. Example: mung bean, black bean, peanut…
• Knotweed family (Polygonaceae): Plants have simple leaves, alternate arrangement, sheaths often clasping the stem. Example: knotweed, Chinese knotweed…
• Nightshade family (Solanaceae): Plants have racemes or solitary flowers, berries or drupes. Example: tomato, eggplant, potato…
• Aralia family (Araliaceae): Plants have compound leaves, umbels of flowers, berries. Example: ginseng, aralia…

4. Latin Names of Some Medicinal Plants:

• Betel nut: Areca catechu
• Carrot: Daucus carota
• Wedelia chinensis: Wedelia chinensis
• Orange: Citrus sinensis
• Chinese knotweed: Polygonum multiflorum
• Job’s tears: Coix lachryma-jobi
• Stemona: Stemona tuberosa
• Orchid: Orchidaceae
• Plantain: Plantago major
• Leonurus sibiricus: Leonurus sibiricus
• Garlic: Allium sativum
• Star anise: Illicium verum
• Betel leaf: Piper betle

5. Some Additional Information:

• Arecolin: A substance found in betel nut, stimulating the nervous system, helping to stay alert, and increasing muscle strength.
• Bract: A leaf growing in the axil of a flower, which can have different colors and shapes.
• Bud: The stage before a flower blooms, the flower will go through various bud stages such as spiral, valve, overlapping…
• Parenchyma tissue: Non-specialized tissue, with the function of connecting other tissues, storing nutrients, participating in metabolic processes.
• Chlorenchyma tissue: Type of assimilation parenchyma, containing many chloroplasts, helping plants photosynthesize.
• Plant conservation: There are many methods of plant conservation such as in situ, ex situ, on-farm conservation, field gene bank, in vitro gene bank.

Note:

• Information in this article is for informational purposes only, not a substitute for professional medical advice.
• Using herbs should follow the appropriate dosage and usage methods.
• Always check the source and quality of herbs before using them.