Conclusions
All the extracts obtained from the fruit residues studied here showed
antioxidant capacity, although with different efficiencies. Due to the low
cost and easy availability of fruit residues, which otherwise would be
discharged as waste in the environment, they should be regarded as
potential nutraceutic resources, capable of offering significant low-cost,
nutritional dietary supplements. This study showed that the extracts
obtained from residues of kinnow, litchi and grapes have a tremendous
potential in food and pharmaceutical industry. Grape seeds and litchi
pericarp are rich in phenolic compounds, whereas, the extracts obtained
from kinnow peel, litchi seeds, and grape seeds showed a higher ABTS
and DPPH radical scavenging abilities. The results showed a low
correlation between phenolic content and antioxidant activity for the
six fruit residues analyzed in the study. More studies are needed to
determine the antioxidant ability of non-phenolic compounds present
in fruit residues. The extracts from fruit residues hold promise in food
industry as sources of bioactive compounds. In addition, an established
use of the fruit residues will also help alleviate pollution problems
caused because of the poor disposal of such residues. It is however
necessary to consider both environmental (waste management and
protection against pollution) aspects and economical aspects (extraction
profitability) before the extracts from fruit residues could be
commercially exploited. More research is needed to establish bioavailability
and real benefits of these extracts obtained from fruit residues
in vivo.
Acknowledgements
Authors thankfully acknowledge the financial assistance received
from the Indian Council of Agricultural Research (ICAR), Government
of India under the research project on “Value addition to non edible
parts of fruits and vegetables”. Author Oberoi would like to thank the
AMAAS project of ICAR for financi