**3.2 Structure of the carpel**

The carpel consists of the outer epicarp, middle mesocarp and inner endocarp (**Figure 1a**). The epicarp consists of an epidermal layer and inner thick compact parenchymatous tissue in which fairly prominent vascular strands are located (**Figures 2a** and **3a**). The inner pericarp is also thick with small circular, thin-walled compact.

Parenchymatous tissue (**Figures 2b** and **3b**) in the inner pericarp, the laticiferous canals are seen spreading in all directions. The middle part of the pericarp has wide air chambers and thin reticulate layers of parenchyma cells (**Figures 3a, b**) at certain places, thick horizontal layers of cells occur in between the outer and inner pericarp.

*(a) T.S. of a carpel with numerous ovules on marginal placentation; and (b) T.S. of carpel with ovule enlarged. IEP: inner epicarp; Ne: nectary; OEC: outer epicarp; Ov: ovary; Ovl: ovule; and Pl: plancenta.*

*Detailed Pharmacognostical Standardization Studies on* Calotrophis Procera *(Aiton) Dryand… DOI: http://dx.doi.org/10.5772/intechopen.104549*

#### **Figure 2.**

*(a) T.S. of pericarp: outer part; and (b) T.S. of pericarp: inner part. Ec: epicarp; IPe: inner pericarp; Ope: outer pericarp; and Me: mesocarp.*

This horizontal plate of cells possesses small scattered vascular strands. In the outer pericarp also, there are numerous small vascular strands dispersed profusely in the parenchymatous ground tissue (**Figure 4a, b**).

#### **3.3 Ovules and seeds**

The ovules occur in marginal placentation a thick massive placental tissue occurs along one side of the carpel. On this elongated cylindrical placental tissue occurs, numerous club-shaped ovules (**Figures 1b**, **5**, and **6a**).

The ovules are broad along the outer part and narrow towards the inner part (**Figure 5**). On the outer part of the carpel, there are numerous, curved elliptical, darkly stained appendages which are the nectarines (**Figures 5** and **6a**, **b**).

#### **3.4 Powder microscopy**

In the powder preparation, fragments of tissues of the pericarp, seed coat and cell inclusions are seen. The inner surface of the pericarp consists of elongated, rectangular, thin-walled cells (**Figure 7a**). These cells have straight cell walls. The cells are parallel to each other forming a dense mat (**Figure 7a**). The outer surface of the pericarp

**Figure 3.**

*(a) T.S. of pericarp outer part showing vascular elements; and (b) T.S. of pericarp inner part. IZ: inner zone; OZ: outer zone; Pe: pericarp; and Vs: Vascular strand.*

**Figure 4.** *(a and b) T.S. of pericarp with scattered vascular strands. Pe: pericarp; Se: segment of fruit wall; and Vs: vascular strand.*

*Detailed Pharmacognostical Standardization Studies on* Calotrophis Procera *(Aiton) Dryand… DOI: http://dx.doi.org/10.5772/intechopen.104549*

#### **Figure 6.**

*(a) T.S. of carpel enclosing the ovules with peripheral nectarines; and (b) Nectaries enlarged. Ne: nectary; Ovlovule; and Pe: pericarp.*

#### **Figure 7.**

*(a) A piece of inner pericarp showing elongated compact parallel parenchyma cells; and (b) Surface view of the outer pericarp where the cells are polygonal with thick straight anticlinal walls and stomata. Aw: anti clinal wall; Ec: epidermal wall; Sc: subsidiary cell; and St: stomata.*

consists of wide polygonal cells with thick, straight anticlinal walls. Stomata are also frequently seen on the outer epicarp. The stomata have narrow stomatal aperture and elliptical guard cells. The stomata appear to be paracytic type (**Figure 7b**).

Broken pieces of seed coats are frequently seen in the powder. The abundance of epidermal trichomes of non-gladular type are seen on the seed coat. The trichomes are thick at the base and become narrowly pointed at the tip. The cell walls of the trichome are thick and lignified and the cell lumen is narrow and canal like (**Figure 8a**, **b**). The trichomes are 130 μm long and 15 μm thick.

The epidermal cells of the seed coat are angular, polygonal and compact (**Figure 8a** and **9b**). Laticiferous canals are commonly present in the pericarp of the fruit. The laticiferous are long, canal-like, non-septate and unbranched. They contain dense white latex secreted from the laticifer (**Figure 9a**). The seeds have dense accumulation of different sizes of oil bodies. They appear white spherical bodies floating in water (**Figure 10a**). Prominent spherical or elliptical starch

*Detailed Pharmacognostical Standardization Studies on* Calotrophis Procera *(Aiton) Dryand… DOI: http://dx.doi.org/10.5772/intechopen.104549*

#### **Figure 8.**

*(a) A broken piece of seed coat showing polygonal epidermal cells and non-glandular epidermal trichomes; and (b) Clusters of non-glandular trichomes seen in powder. Ec: epidermal cells; and NGT: non-gladular trichomes.*

grains are common in the powder. When stained with IKI, the starch grains appear black or dark blue (**Figure 10b**). The seeds of *Calotropis* are flat, obovate and thin. One end of the seed is narrow and pointed. This pointed end of the seed bears a tuft of thin, white, soft trichomes. This tuft of trichomes is called coma. The trichomes of coma are also seen in the powder. These trichomes have thick walls and wide lumen. They are unicellular and unbranched. The trichomes are 30 μm thick (**Figure 10c**).

#### **Figure 9.**

*(a) A piece of pericarp tissue with unicellular, unbranched laticiferous canal; and (b) Seed coat fragment showing thick-walled epidermal cells. Ec: epidermal cells; and LtF: laticifer.*

The ash is mainly for the identification of carbonates, silicates, phosphates, sodium, potassium, calcium and magnesium without an organic matter. The obtained total ash value (11.4%), Water soluble ash (7.5), Acid insoluble ash (1.8), Foaming Index (<100), Swelling Index (52%), Loss on Drying (16.7%) And the extractive values are mainly for the estimation of primary and secondary metabolites in Petroleum ether (5.65%), it might be terpenoids, sterols, lipids and waxes and apart from Ethyl acetate extract (2.25%), Acetone extract (3.17%), Methanolic extract (4.53%) contains tepenoids, phenols, and glycoside containing components may be present. Distilled Water (10.11%) and Hydro-alcohol (6.05%) contains polyphenols, tannins and alkaloids present (**Tables 1–3**).

For herbal drugs, florescence analysis is very primary tool for the determination of constituents, this florescence analysis provides an informative data on nature of constituents [12]. The chemical reagents were used for the powdered drug analysis and *Detailed Pharmacognostical Standardization Studies on* Calotrophis Procera *(Aiton) Dryand… DOI: http://dx.doi.org/10.5772/intechopen.104549*

#### **Figure 10.**

*Oil globules of different sizes found in the powder; (b) Starch grains stained with potassium iodide; and (c) Trichomes from coma of the seed. OB: oil bodies; SG: starch grains; and Tr: trichomes.*


#### **Table 1.**

*Morphological characters of Calotropis procera fruit.*

observations are available in visible light and UV lights of Short and long wave lengths (**Table 4)**.

The preliminary phytochemical screening on *Calotropis procera* was done by using hexane, n-butanol, ethanol, acetone, ethyl acetate, methanol and hydro alcoholic


#### **Table 2.**

*Results for physicochemical parameters.*


#### **Table 3.**

*Results of extractive values.*


#### **Table 4.**

*Fluorescence analysis on Calotrophis procera fruit.*




**Table 5.** *Preliminary phytochemical tests for identification of the class of primary and secondary components in the extract of C. procera fruit.*
