Ascorbic Acid Contents in Chili Peppers ( Capsicum L . )

The genus Capsicum commonly known as chili pepper is a major spice crop and is almost cosmopolitan in distribution. The nutritive value of chili pepper is largely determined by ascorbic acid content. The fruits at five ripening stages viz., (M1, M2, M3, M4 and M5) from seventeen cultivars of Capsicum annuum L and one cultivar of Capsicum frutescens L were analyzed for ascorbic acid content. Among eighteen genotypes the C. annuum var. IC: 119262(CA2) showed higher ascorbic acid content (mg/100g) FW i.e., 208.0±0.68 (M1), 231.0±0.66 (M2), 280.0±0.31 (M3), 253.0±0.34 (M4) and 173.7±0.27 (M5). The study revealed that the gradual increase in ascorbic acid content from green to red and subsequently declined in the lateral stages (red partially dried and red fully dried fruits). The variability of ascorbic acid content in the genotypes suggests that these selected genotypes may be use full as parents in hybridization programs to produce fruits with good nutritional values.


Introduction
A wealth of information and scientific evidences are rapidly accumulating the beneficial effects of wide variety of food components on human health.The most important vitamin in fruits and vegetables is vitamin C 90% of the ascorbic acid in human diet was supplied by them.Chili peppers are the most important vegetable cum spice because of its colour, taste, pungency, flavour and aroma grown in tropical and sub tropical regions of the world.They are extremely popular for the abundance content of vitamin C larger than other vegetables and fruits commonly recognized as a source of this substance (Durust et al., 1997;Osuna-Garcia et al. 1998).The ascorbic acid (Vitamin C) content in chili peppers has been reported by few workers (Howard et al., 1994;Lee et al., 1995;Mishra, 2004;Sheela, 2004).Large varietal variations in ascorbic acid content have been reviewed by Manju et al. (2002) and Antonious et al. (2006).Ascorbic acid content was increases with fruit ripening while, losses during post harvest handlings (Martinez et al., 2005).Despite many reports of ascorbic acid content in chili peppers is inadequate.There fore the present study is taken up to estimate the content of ascorbic acid during ripening in eighteen genotypes of chili peppers (Capsicum L) and to select genotypes having high content of ascorbic acid as parents in breeding programs.

Materials and methods
Seventeen cultivars of C. annuum L and one cultivar of Capsicum frutescens L were grown in randomized design with three replicates at the experimental farm of Andhra University, Visakhapatnam.The healthy fruits were harvested at five ripening stages viz., Green (M 1 ), Breaker (M 2 ), Red (M 3 ), Red partially dried (M 4 ) and Red fully dried (M 5 ).The fruits were washed with tap water and cut into small pieces and homogenized with the help of mortar and pestle by adding 5 ml of 4% oxalic acid.The homogenates were centrifuged at 5000 rpm for 10 minutes then the supernatants were filtered with 541 Whatmann filter paper the obtained residues were made up to 25 ml with 4% oxalic acid.The ascorbic acid content was estimated by using 2, 4. dinitrophenylhydrazine reagent in conjunction with spectrophotometer at 540 nm (Sadasivam and Manickam, 1992) five samples from each lot were analyzed.

Results and discussion
From the (Tab. 1 and Fig. 1) shows that a gradual increase of ascorbic acid content from green to red ripening while, decreased in the lateral stages (i.e., red partially dried and red fully dried) these results were agreed according to the data reported by Osuna-Garcia et al. (1998) and Martinez et al. (2005).The genotypes showed considerable variation in ascorbic acid content ranged from 44.3mg to 280mg/100g FW and were categorized under hot peppers in agreement with previous observations (Howard et al., 1994;Lee et al., 1995;Manju et al., 2002;Antonious, et al. 2006).Among the eighteen genotypes C. annuum var.IC: 119262(CA 2 ) showed highest ascorbic acid content in all the ripening stages i.e., 208.0±0.68 (green), 231.0±0.66 (breaker), 280.0±0.31(red), 253.0±0.34 (red partially dried) and 173.7±0.27(red fully dried) while,   FW) and high (201-300mg/100gFW) however, the medium category was most frequently described by Khadi et al. (1987) andSimmone et al. (1997).High content of ascorbic acid was pronounced in red ripening and most of the chili peppers were fall under medium category of ascorbic acid content however, the lowest contents were recorded in red partially dried and red fully dried fruits.This may be due to decrease in the moisture content in fruits, a similar view point is also shared by Osuna-Garcia et al. (1998), Lalitha Kumari et al. (1999), Gnayfeed et al. (2001), Robi and Sreelatha Kumari (2004) and Martinez et al. (2005) in diverse cultivars of Capsicum L. Our results suggests that six genotypes (i.e., CA 2 , CA 18 , CA 22 , CA 21 , CA 20 and CA 16 ) (Tab. 1) showed best ascorbic acid content ranged from 171.3 to 280 mg/100g FW in M 1 , M 2 , M 3 , M 4 and M 5 fruits can be recommended in breeding programs to produce high ascorbic acid content varieties.

Conclusions
The present study reports that the ascorbic acid content in eighteen genotypes of Capsicum L showed variation from one another, among the genotypes CA 2 represents more ascorbic acid.The study revealed that ascorbic acid content increased from green to red while, decreased in red partially dried and red fully dried fruits.

Fig. 1 .
Fig.1.Ascorbic acid contents in eighteen genotypes of chili peppers (Capsicum L.) at five ripening stages.Bars mean value of ascorbic acid content.
Tab. 1. Mean ascorbic acid contents in eighteen genotypes of chili peppers (Capsicum L.) at five ripening stages.