*3.1.1. General screening of carbohydrates*

Experimental: 1 ml Molisch reagent (a solution of α-naphthol in ethanol) is added to 2 ml aqueous extract and few drops of concentrated sulfuric acid are slowly dripped and the resulted solution is shaken carefully. The appearance of a violet ring at the interface of the two liquids indicates the presence of carbohydrates in the aqueous extracts.

In the case of sea buckthorn aqueous extract, the solution turns purple-red and a brown precipitate is obtained from gooseberry aqueous extract.


**a.** *Benedict test*: to 1 ml of aqueous extract 5 ml Benedict's reagent (a complex solution of sodium carbonate, sodium citrate, and copper sulfate pentahydrate) was added and the resulted mixture is boiled for 5 min. Initially, the solution turns green and upon boiling a

Qualitative Analysis of Phytochemicals from Sea Buckthorn and Gooseberry

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**b.** *Fehling A test*: to 1 ml aqueous extract few drops of Fehling A reagent (aqueous solution of copper sulfate) are added; a green coloration indicates the presence of reducing sugars.

**c.** *Fehling B test*: to 1 ml aqueous extract few drops of reagent (a solution of potassium sodium tartrate in sodium hydroxide) are added and the formation of a brown coloration is

**d.** *Barfoed test*: this test reveals the presence of reducing monosaccharides. To 1 ml aqueous extract, 3 ml Barfoed's reagent (solution of copper acetate) are added, boiled for 2 min and

**e.** *Trommer test*: to 3 ml of aqueous extract an ml of 2.5% copper sulfate and 2 ml of 5% sodium hydroxide is added and the mixture is boiled for 3 min. Initially, a blue precipitate appears which turn red upon heating, thus indicating the presence of reducing sugars.

of 0.1 M silver nitrate is poured to the resulted solution. After 5–10 min of boiling a silver

**g.** *Moore test*: this test particularly reveals the presence of glucose. To 2 ml of aqueous extract an equal volume of 5% NaOH is added and the mixture is boiled for 5 min with. The solu-

By performing Molisch's test, it reveals that both aqueous extracts contain different classes of carbohydrates. Specific qualitative test for carbohydrates reveals the presence of monosaccharides in gooseberry aqueous extract and of di-, oil- and polysaccharides in both sea buckthorn

Hexoses are monosaccharides that contain six carbon atoms and are divided into aldohexoses and ketohexoses depending on the functional group [26]. Three qualitative methods reveal

**a.** *Seliwanoff test*: to 1 ml of aqueous extract, 3 ml of Seliwanoff's reagent (a mixture of resorcinol in hydrochloric acid) is added and boiled for 2 min. A red solution is obtained

**b.** *Cobalt chloride test*: this test indicates the presence of either glucose or fructose or both. Three ml aqueous extract are mixed with 2 ml cobalt chloride and the solution in boiled. After cooling, few drops of 4% NaOH solution are added and the results are as follows: a greenish-blue solution (glucose), purplish-violet solution (fructose), or the upper layer

turns greenish-blue, while the lower layer purplish (both glucose and fructose).

mirror is formed (silver precipitates in the presence of reducing sugars).

tion has initially a yellow coloration that changer to reddish-brown.

the presence of hexose sugars and the results are presented in **Table 4**.

OH is added and then a solution

red, yellow, or green precipitate is formed.

then cooled. A red precipitate is formed.

**f.** *Tollens test*: to 4 ml of aqueous extract a drop of dilute NH4

a positive response.

and gooseberry extracts.

*3.1.3. Detection of hexose sugars*

indicated a positive reaction (**Figure 6**).

**Table 3.** Qualitative screening of carbohydrates.

#### *3.1.2. Detection of reducing sugars*

The general definition of reducing sugars is any type of sugar that can act as a reducing agent due to the free aldehyde or ketone groups. All monosaccharides are reducing sugars, along with some di-, oil- and polysaccharides. Several tests are available for detecting reducing sugars in aqueous extracts (**Figures 4** and **5**) (**Table 3**) [25].

**Figure 4.** Carbohydrates in sea buckthorn aqueous extract.

**Figure 5.** Reducing sugars from gooseberry aqueous extract.


By performing Molisch's test, it reveals that both aqueous extracts contain different classes of carbohydrates. Specific qualitative test for carbohydrates reveals the presence of monosaccharides in gooseberry aqueous extract and of di-, oil- and polysaccharides in both sea buckthorn and gooseberry extracts.
