1. What is Water Soluble Extractive Value?

Definition: Water Soluble Extractive Value indicates the nature of chemical constituents present in drugs or plant materials that are soluble in water.

Purpose: It helps in quality control of herbal drugs and plant materials by measuring the amount of water-soluble components.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( EV \) — Water Soluble Extractive Value
• \( A \) — Dish Weight (kg)
• \( B \) — Dish Residue Weight (kg)
• \( W \) — Sample Weight (kg)

Explanation: The difference between dish with residue and empty dish is multiplied by 4 and 100, then divided by the sample weight.

3. Importance of Extractive Value

Details: Higher extractive values generally indicate better quality plant material with more water-soluble active constituents.

4. Using the Calculator

Tips: Enter the dish weight, dish with residue weight, and sample weight in kilograms. All values must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: Why multiply by 4 and 100 in the formula?
A: The multiplication by 4 accounts for the standard extraction process (25ml solvent per gram), and 100 converts to percentage.

Q2: What's a typical value range?
A: Values vary by plant material but typically range from 5% to 50% for most medicinal plants.

Q3: What if my sample weight is in grams?
A: Convert grams to kg (divide by 1000) or adjust the formula accordingly.

Q4: How precise should measurements be?
A: Use analytical balance with at least 0.0001 kg precision for accurate results.

Q5: What does a low extractive value indicate?
A: Low values may suggest poor quality material, improper drying, or low water-soluble constituents.