Study of morphological and anatomical characteristics of Cosmos (Cosmos bipinnatus cav.) Herb

Abstract

Cosmos bipinnatus Cav., or Mexican aster, from the aster family (Asteraceae) is an annual herbaceous plant that is common in the southwestern United States and Mexico. It is widely cultivated in many countries of the world, as well as in Ukraine as an ornamental plant. The plant is rich in carbohydrates, phenolic and nitrogen-containing compounds, terpene substances, and mineral elements. The chemical composition of the plant and the pharmacological effect of BAS complexes by scientists from different countries of the world have been studied. The anti-inflammatory, antimicrobial, antioxidant, hepatoprotective, larvicidal, and insecticidal effects of raw materials and biologically active complexes of cosmeia bipinnate have been revealed. We also conducted phytochemical studies of the raw materials of this plant of domestic origin, which creates prospects for the development of medicinal products based on it. In order to include cosmeia bipinnate in the assortment of pharmacopoeial plants of Ukraine, it is necessary to develop criteria for standardization of raw materials according to the requirements of the Federal State Administration of Ukraine, among which there is conformity according to morphological (identification A) and anatomical (identification B) features. For standardization, we chose cosmeia bipinnate herb. The aim of the work was to study the morphological and anatomical diagnostic features of the cosmeia bipinnate herb. Materials and methods: Cosmos bipinnatus herb, a mixture of the most popular in Ukraine varieties Dazzler, Purity and Pink sensation Cosmos bipinnatus Cav., was chosen as the research object. The raw material was harvested in the flowering phase of the plant in July - August 2023 - 2024 in the Kharkiv region, Ukraine. For the experiments, fresh and air-dried raw materials were used, which were dried in the shade. The anatomical structure was studied using a Granum microscope at a magnification of 40-600 times, photographed with a ScienceLab DCM820 microscope camera, the photos were processed in TSView 7 and Adobe Photoshop CC 2021 programs. Fresh raw materials for anatomical research were fixed in a mixture of ethanol - glycerol - water (1:1:1), air-dried raw materials were clarified in chloral hydrate. Preparations of the epidermis of the stem, leaf, ligulate and tubular flowers, bracts of involucre, as well as cross-sections of the stem were prepared for microscopic study. Morphological characteristics of raw materials were determined visually with the naked eye and with a magnifying glass (x10).Research results: the following morphological diagnostic features of cosmeia bipinnate whole herb include: cylindrical stems, often hollow in the central part, pubescent. The leaves are pinnatisected and double pinnatissected into linear elongated segments, sessile, opposite, pubescent, pinnate venation. Inflorescences are capitula located on long axes. The marginal flowers are colored in white, pink or red-purple color, the middle ones are yellow. The smell of raw materials is characteristic. Anatomical diagnostic features of the examined herb include: cells of the upper and lower epidermis of the leaf are parenchymal, polygonal, with weakly sinuous walls, stomata of anomocytic type, and anisocytic type also on the lower epidermis. The epidermis is pubescent on both sides with multicellular caterpillar-like hairs with a broad base, 2-3 cell thick-walled conical and unicellular papilla-like hairs. There are simple 3-4 cell thick-walled hairs along the edge of the leaf. The veins of the leaf are accompanied by secretory ducts with brown contents. The cells of the upper and lower epidermis of marginal flowers are elongated along the veins, the cell walls are thin and wavy. Sometimes there are simple multicellular hairs. Papillary hairs are numerous. Veins are accompanied by secretory ducts with brown contents. The cells of the epidermis of tubular flowers are parenchymal at the edge, straight, thin-walled and tortuous in the central part. Stomata of the anomocytic type. Simple multicellular conical and glandular hairs with a multicellular head are present. Caterpillar hairs are rare. On the epidermis of marginal and tubular flowers, there are oval essential oil glands, which consist of two rows of cells arranged in four tiers, there are secretory ducts with brown contents and spherical pollen grains with a sharp-toothed surface. The epidermis of the leaves of the outer wrapper is convolute-walled with thickened membranes, the cells are elongated along the edge, the edge of the leaves is covered with numerous simple multicellular and club-like hairs, there are essential oil glands and secretory ducts with brown contents.

Key words: Cosmos bipinnatus herb, Cosmos bipinnatus Cav., morphological characteristics, anatomical characteristics, microscopic examination, raw material standardization.