2. Plant based alkaloid and their Activities: 2.1 Glycine max (Fabaceae) Local name: Soya beans. Local region: Faridpur, Rangpur in Bangladesh. Alkaloids and their activities: It is generally known as Soya beans. People generally used its seeds. It contains 3-O-methylD-chiro-inositol active chemical constituents. There are some ingredients of soya beans such as: α-linolenic acid act as essential fatty acid, hypocholesterolemic, hypotriglyceridemic, improves heart health. Isoflavones act as estrogenic, improves the function of digestive tract, prevent prostate and colon cancer. Lecithins improve the metabolism of lipid; the abilities of learning also act as anti-carcinogenic, immunostimulator. Peptides play a good role in reducing body fat. Phytosterols act as hypocholesterolemic. Protein act as hypocholesterolemic, antiatherogenic, body fat reduce. 2.2 Tamarindus indica (Fabaceae) Local name: Tatul tree Local region: Planted throughout Bangladesh. Alkaloids and their activities: Commonly known as Tatul tree, seeds and fruits are its usable portion. It has some active chemical constituents such as flavonoid, polysacc-haride. Tamarindus indica contain some fatty acids studied as methyl ester such as: methyl-nheptanoa, 1-Octanoate, n-Nonanoate, nonanoic acid, nTridecanoic, n-Tetradecanoate, methyl-pentadecanoic, nHexadecanoate, n-Heptadecanoate, n-Octadecanoic, nNonadecanoate, n-Eicosenoate, n-Docosanoate, methyl-ntricosanoate, n-Tetracosane, methyl-n-Pentadecanoic, nHxocosanoate, n-Heptacosanoate, nonacosatrienoic acid, nNnacosanate, detricasonic, 9-Decenoate, pentadecatrienoate, heptadacanoate, heptadecadienoat, 10-Octadecenoicacid oleate, nenodecenoic acid, tetracosadienoate, n-Pentacosenoic acid n-Hexacoseoic acid, 24R-Ethyl cholest-5-en, 3β-ol, 9ß, 19-Cyclo-4 ß4, 4, 14, ß-trimethyl-5ß-cholestan-3ß-ol. 2.3. Allium cepa (Alliaceae) Local name: Piyaj (Bengali) Local region: Cultivated in most of the districts of Bangladesh. Alkaloids and their activities: Allium cepa is usually called onion plant; people generally used its bulb. Onion acts through its active chemical constituents these are S- methyl cysteine sulphoxide and allyl propyl disulphide. [2,4] Research on animal and clinical trials support the use of Allium cepa as anti asthmatic [88, 89], anti diabetic, anti viral anti thrombotic, hypo cholestremic, anti inflammatory, anti oxidant, aphrodisiacs, cardiotonic, diueretic, expectorant, stimulant, anti cancer, platelet aggregation inhibitor, insecticidal properties, and in osteoporosis treatment. 2.5. Azadirachta indica (Meliaceae) Local name: Neem Local region: Planted all over Bangladesh. Alkaloids and their activities: Another important medicinal plant in Bangladesh is Azadirachta indica called neem. Plant’s leaf and seed are used as many medicinal purpose. Nimbidin is its active chemical compound. Azadirachtin, meliacin, gedunin, nimbidin, nimbolides, salanin, nimbin, and valassin are biologically active phytochemiclas, the four best limnoids compounds are: azadirachtin, salannin, meliantriol, and nimbin having insecticidal and pesticidal activity. Pharmacological actions of this plant are includes antinematodal, antipyretic, antispasmodic, insecticidal, antispermatogenic, antitumor, hypercholesteremic, hypoglycaemic, immunomodulator, abortifacient, analgesic, antihelminthic, antibacterial, antiyeast, antiulcer, antifertility, antifilarial, antifungal, antihyperglycemic, anti-inflammatory, antiviral, antimalarial and diuretic activity. 2.6. Brassica juncea (Brassicaceae) Local name: Mustard Local region: Cultivated in different districts. Alkaloids and their activities: Brassica juncea is locally known as mustard. Seed and leaf are most usable parts. It has isorhamnetindi glucoside as active chemical compound. Phenolic compounds, carotenoids, glucosinolates are so much rich in this plant which show greater performance of anti-oxidant, hepatoprotective activity, lowering of cardiovascular disease risk and inflammations is performed by linoleic acid and also act as reducing the risk of colon and breast cancer. Active antioxidants such as β-carotene, α- tocopherol, indoles and isothiocyanate are also present. Vegetable of Brassica juncea contain glucosinolates, flavonoids, vitamins and mineral nutrients.