Medicinal Plants Lecture 1 2024/2025 PDF

Medicinal plants 2024/2025 Lecture 1 Dr. Amal F. Soliman Dr. Walaa Safwat Associate Professor of Pharmacognosy Lecturer of Pharmacognosy  ‫قسم العقاقري‬ ‫‪Pharmacognosy Dep...

Medicinal plants 2024/2025 Lecture 1 Dr. Amal F. Soliman Dr. Walaa Safwat Associate Professor of Pharmacognosy Lecturer of Pharmacognosy  ‫قسم العقاقري‬ ‫‪Pharmacognosy Department‬‬ ‫املقررات الىت يقوم القسم بتدريسها‬ ‫‪:‬علم العقاقير ‪Pharmacognosy‬‬ ‫ هو العلم الذي يهتم بدراسة االدوية الطبية المشتقة من النباتات والمصادر الطبيعية األخري‪.‬‬ ‫)‪❑ Medicinal plants (PG101‬‬ ‫نبااتت طبية‬ ‫‪❑ Pharmacognosy 1 & 2‬‬ ‫عقاقري ‪ 1‬و ‪2‬‬ ‫‪❑ Phytochemistry 1 & 2‬‬ ‫كميياء عقاقري ‪ 1‬و ‪2‬‬ ‫‪❑ Phytotherapy‬‬ ‫العالج اب ألعشاب‬  ‫املس توى ا ألول – الفصل ادلراىس ا ألول‬ ‫‪Medicinal plants‬‬ ‫نبااتت طبية‬ ‫)‪(PG101‬‬ ‫ميدترم‪ /‬أأنشطة‬ ‫معىل‬ ‫نظرى‬ ‫شفوى‬  Medicinal plants (PG101) Course aims ‫أأهداف املقرر‬ ❑Students should acquire knowledge concerning dusting powders, plant anatomy, physiology and medicinal plants and their taxonomy. ❑In this course, the student will study importance of natural products, preparation of natural products-derived drugs including collection, storage, preservation and adulteration.  Lecture 1 ‫احملارضة ا ألوىل‬ Plant Taxonomy Anatomy Physiology Plant Anatomy ‫عمل ترشحي النبات‬ Plant anatomy describes the structure and organization of the cells, tissues and organs of plants in relation to their Organs development and function = Tissues the study of plant cell and tissue structure Cells  Cell Structure and Function ❑ All living things are made up of cells. ❑ Cells are the smallest working units of all living things. Definition of Cell: A cell is the smallest unit that can perform life functions. Typical Plant cell ❑Each cell consists of living and non-living materials. Plant cell has three regions 1- The cell wall (Non-living) 2- The protoplast (Living) 3- The vacuoles (Non-living) 1-Cell wall ▪ Is semirigid, external, non-living. ▪ Present in plant cell but absent in animal cells. ▪ It give protection and support, covering the living plasma membrane. ▪ A fundamental difference between plant and animal cells is that the plant cell is surrounded by a rigid cell wall, mostly made of polysaccharides (cellulose, hemicellulose, pectin) and lignin. Cell wall is distinguished into three parts: 1- Middle Lamella 2- The primary cell wall 3- The secondary cell wall Cell #1 Cell #2 middle lamella plasma primary cell wall membrane (cellulosic) secondary cell wall (lignified) pit primary pit field (pits of two adjacent (collection of several cells = pit-pair) plasmodesmata) plasmodesmata Cell #1 Cell #2 1- Middle Lamella ▪ It is the first partition arises between two cells. ▪ It made up of mostly of calcium and magnesium pectate. 2- The primary cell wall ▪ This second layer consists mainly of cellulose molecules. ▪ It capable of extension as the cell grows. 3- The secondary cell wall ▪ When the cell ceases to enlarge, the protoplast secretes additional substances on the inner of the primary wall, in the form of successive layers. These layers consists mainly of cellulose, hemicellulose, lignin and suberin. ▪ In supporting cells as fiber and vessel cells. ▪ The secondary wall differs from the primary walls in that it is incapable of increase in area. Lignified elements stained red upon application of phloroglucinol solution in the presence of hydrochloric acid  Pits and plasmodesmata ▪ Most cells have thin areas in the primary walls (no secondary wall layer), which have small pores through which strands of cytoplasm (plasmodesmata) connect the protoplasm of one cell with that of the adjacent cell. ▪ Plasmodesmata aid in the movement of materials and transmit stimuli. Pits A pit is a region in the cell wall in which no secondary wall is deposited. ❑ There are three types of pits: 1- Simple 2- Bordered 3- Half-bordered Simple pits: may be found in certain parenchyma cells, in phloem fibers and in sclereids. ‫لالطالع فقط‬ Bordered and half bordered pits: occur mainly in the conducting and mechanical cells of xylem such as vessels and tracheids.  Plant cell has three regions 1- The cell wall (Non-living) 2- The protoplast (Living) 3- The vacuoles (Non-living) 2-Protoplast ▪ The protoplast, consisting of the plasma membrane and all inside of it except any non-living materials as crystals, starch grains and contents of the vacuoles. ▪ The protoplast is surrounded by a delicate membrane (the plasma membrane) and include two major components (the cytoplasm and the nucleus). A- The plasma membrane ▪ Bilayer of phospholipid (polar head & nonpolar tail). ▪ Proteins embedded and adhered to the surface. ▪ The lipid molecule consists of a fatty acid tail (lipophilic) and a head (hydrophilic), the fatty acid tails face towards the inside and the hydrophilic heads outwards to the outer protein layers. Functions of plasma membrane: 1- protection of the cell. 2- It is selectively permeable and regulates the movement of molecules in and out of the cell. 3- Sensory transduction ‫نقل االحساس‬, i.e., the sensing and initiation of the cellular response to the changed environmental conditions.  B- The cytoplasm The cytoplasm appears as a semi fluid in which the organelles and cell inclusions are found. 1- Nucleus (Leader of the cell) ▪ Large spherical structure enclosed by an envelope of two membranes that is perforated by nuclear pores. A net work of chromatin fibers (extended chromosomes) and a nucleolus are present inside. ▪ The chromatin material includes Deoxyribonucleic acid (DNA), ribonucleic acid (RNA) and proteins. Function: The nucleus controls all the activities of the cell and the transmission of hereditary characters ‫الصفات‬ ‫الوراثية‬. 2- The Endoplasmic reticulum ‫الش بكة الإندوبالزمية‬ Two types of ER are known: - Smooth ER lacks ribosomes & makes proteins USED in the Cell and synthesis of lipids and phospholipids. - Rough ER has ribosomes on Its surface & makes proteins to EXPORT. Function of ER 1- Forming the skeleton of the cell. 2- Translocation of various substances. 3- Protein and fat synthesis. 4- Helping in keeping certain enzymes and metabolites separate. 3- Ribosomes ▪ They are minute, rounded to spherical bodies. ▪ They are composed of RNA and protein. ▪ They are characterized by their high protein synthesis ‫تصنيع البروتين‬. 4- Golgi apparatus ▪ Stacks of flattened sacs. ‫أأكوام من الأكياس املسطحة‬ Function: Its function is: packaging and secretion of proteins. It receives proteins from ER. It packages it into membrane-bound vesicles, which are then transported to various destinations. Both Golgi apparatus and ER are responsible for cell wall formation. 5- Mitochondria It consists of two Membranes 1- The outer membrane: Which is continuous and encloses a central space. 2- The inner membrane: Sends folds into their central space which are called cristae. The mitochondrial inner chamber is filled with homogenous matrix. Function of mitochondria. ▪ It is called “the powerhouse of the cell” because they produce much of the energy necessary for the cell to carry out their functions. ▪ Chemical energy produced by the mitochondria is stored in a small molecule called adenosine triphosphate (ATP). 6- Plastids [ in plant cells only] According to their pigmentation, they are distinguished into three types: 1- Leucoplasts 2- Chromoplasts 3- Chloroplasts a- Leucoplasts ▪ They contain no chlorophyll and are known as colorless plastids. b- Chromoplasts ▪ They do not contain chlorophyll but contain carotenoid pigments and appear as colored plastids. e.g., carrot and tomato. c- Chloroplasts ▪ They contain chlorophyll. ▪ The chloroplast is surrounded by two membranes. ▪ Chloroplast contains stacks of flattened organelles called a thylakoid. One stack of thylakoids is called a grana. Grana float within a cytoplasm- like fluid in the chloroplast called stroma. Function of chloroplasts: It is the organ for photosynthesis. The sunlight is trapped and converted to chemical energy in grana. 7- Lysosomes These are simple spherical sacs bounded by single membrane and contain digestive enzymes. Function: Intracellular digestion.  Plant cell has three regions 1- The cell wall (Non-living) 2- The protoplast (Living) 3- The vacuoles (Non-living) 3-Vacuoles Mature cells of the plants have vacuoles which may enlarge to much an extent that the cytoplasm located adjacent to the cell walls. The vacuoles are filled with cell sap. It is surrounded by lipoprotein membrane (Tonoplast). The vacuole may contain pigments as anthocyanin e.g., Colored petals. 1- A rigid plant cell wall, mostly made of ………. A- lignin B- polysaccharides C- (A and B) D- None of the above 2- Organelle in the cell that is responsible for cell wall formation ………. A- Golgi Apparatus B- Lysosomes C- Mitochondria D- Nucleus  3- Which of the following is nonliving? A- nucleus B- plasma membrane C- mitochondria D- vacuole 4- Lignified elements stained ……. upon application of phloroglucinol solution in the presence of hydrochloric acid A- blue B- red C- green D- yellow