Rats of Organizations III and IV were orally administered MOLE at 62.5 and 125 mg/kg for 21 days and immunized with O antigen (1 ml subcutaneously at 3C4 different sites) on day time 0, 7, and 15 (day time 0 as the 1st day of start of feeding of extract). Detection of Antibody TiterBlood samples were collected 15 days after the second booster dose of antigen from retro-orbital plexus of rats. MOLE at 125 mg/kg improved the antibody titer by 50%. Although there was slight decrease in lymphocytes count (total, B- and T-lymphocytes) in MOLE treated rats, percentage of T-lymphocytes was improved nonsignificantly. and studies exposed designated increase in OD and activation index indicating MOLE-induced splenocytes proliferation. Summary: GC-MS study revealed four fresh compounds in MOLE apart from encouraging its immunomodulatory potential based on humoral immune response, percentage increase in T-lymphocytes count, and induction of splenocytes proliferation. is commonly referred as wonder tree or a wonder tree due to its socioeconomic importance, nutritional values, industrial applications, and its wide use in folk medicine. Its leaves consist of important trace elements, proteins, vitamins, beta-carotene, amino acids, numerous phenolics, and additional phytoconstituents[1,2,3,4] and these are used in Siddha medicine. Different components of its origins, bark, leaves, plants, immature pods, and adult fruits have been reported to possess cardiac and circulatory stimulant, antifertility, antitumor, antipyretic, antispasmodic, antiinflammatory, antiulcer, hypotensive, hypolipidemic, hypoglycemic, hepatoprotective, antioxidant, antifungal and antibacterial activities, and thus encouraging restorative Rbin-1 potential.[2,3,5,6,7] Aqueous draw Rbin-1 out of its leaves has been reported to regulate thyroid hormone and may be used to treat hyperthyroidism.[8] Rbin-1 plant provides a rich and rare combination of zeatin, quercetin, kempferol, and many other phytochemicals. Bioassay-guided analysis of ethanolic draw out of leaves showed the presence of two nitrile glycosides, niazirin and niazirinin, and three mustard oil glycosides, 4-([4-0-acetyl–L-rhamnosyloxy] benzyl) isothiocyanate, niaziminin A and B.[9] Gas chromatography-mass spectrometry (GC-MS) analysis of methanolic extract of leaves (MOLE) and seeds revealed the presence of 16 chemical constituents in Rbin-1 leaf extract with 9-octadecenoic acid (20.89%), L-(+) ascorbic acid, 2,6-dihexadecanoate (19.66%), and 14-methyl-8-hexadecenal (8.11%) while major ones while only five in seed draw out and they were oleic acid (84%), L-(+)-ascorbic acid, 2,6-dihexadecanoate (9.80%), 9-octadecenoic acid (1.88%), methyl ester-hexadecanoic acid (1.31%).[4] Monoterpenoid compounds (81.8%) in essential oil of extracted by hydrodistillation and analyzed by GC and GC-MS have been reported and its oil had highest percentage (25.2%) of has also been documented using high-performance liquid chromathography (HPLC) and MS/MS techniques.[11] Alcoholic draw out of leaves has been reported to contain 15 parts and major ones were hexadecanoic acid, ethyl palmitate, palmitic acid ethyl ester, 2,6-dimethyl-1, 7-octadiene-3-ol, 4-hexadecen-6-yne, 2-hexanone, 3-cyclohexyliden-4-ethyl, E2-dodecenylacetate, hi-oleic safflower oil, and safflower oil.[12] Immunomodulatory studies about MOLE ethanolic extract in normal and immune-suppressed mice magic size exposed significant rise ( 0.05) in phagocytic index and hematological and serum enzyme levels.[13] leaf powder supplementation has been observed to ITGA6 stimulate immune response in HIV-positive people[14] and lectin present in pods has been reported to modulate the immune system.[15] Many workers observed immunomodulatory effect of alcoholic and hydro-alcoholic extracts of leaves[16] and roots.[17] The present study was undertaken to investigate the major marker phytoconstituents in methanolic extract of MOLE using GC-MS technique and evaluation of its immunomodulatory potential employing humoral immune response and splenocytes proliferation assays. Materials and Methods Flower MaterialLeaves of were collected from Veterinary College Campus, Mathura. The identity of the flower material was confirmed by Division of Botany, RBS College, Bichhpuri, Agra, India, based on taxonomic features of whole flower material. Extraction of Flower MaterialHot-methanolic draw out of shade-dried and coarsely powdered MOLE was prepared in soxhlet apparatus by sizzling percolation method. MOLE draw out was concentrated to dryness using rotatory evaporator under reduced pressure and low heat ( 40C). The draw out was kept in air-tight.