Changes in the ascorbic acid content of some tropical leafy vegetables during traditional cooking and local processing

1987 ◽  
Vol 23 (1) ◽  
pp. 9-17 ◽  
Author(s):  
K. Oteng-Gyang ◽  
J.I. Mbachu
2021 ◽  
Vol 9 (3) ◽  
pp. 063-069
Author(s):  
Aleya Nasreen ◽  
Zakaria Ahmed ◽  
Mahabub Ali ◽  
Taslima Rahman ◽  
Tahmina

Vitamin C, also known as ascorbic acid is essential nutrients that cannot produce in human body and meet up through diet. Jute leaves contain L-ascorbic acid. The amount of L-ascorbic is unknown in different varieties developed by Bangladesh Jute Research Institute. L-ascorbic acid content is affected by cooking or processing and preservation. Therefore, the experiment was conducted to investigate the content of vitamin C in the fresh jute leaves as well as the effect of cooking and preservation methods on L-ascorbic acid content in jute leaves. Fresh jute leaves of different varieties contain different amount of L-ascorbic acid 0.39g/10g to 0.64g/10g in Corchorus olitorius and 0.64g/10g to 0.92g/10g in Corchorus capsularis. C. capsularis contain more amount of L-ascorbic acid than the C. olitorius. Jute leaves of C. olitorius retain 95% L-ascorbic acid and C. capsularis retain 62% L-ascorbic acid after 15 min of boiling. Vinegar soaking leaves release more L- ascorbic acid by 5 min than the fresh leaves and then the L-ascorbic acid content was reduced by 15 min in both the species. Spraying vinegar treatment releases more L-ascorbic acid and increasing up-to 30 min treatment. Both oven dried and cold dried leaves retain small amount of L-ascorbic acid. L-ascorbic acid content was reduced in preserved jute leaf tea and soup powder also in both species. Usually, leafy vegetables are cooked before consumption and sometimes preserved vegetables are consumed when fresh vegetables may not available. So, this study may be useful to know the actual intake of L-ascorbic acid from the processed or preserved jute leaves.


Planta Medica ◽  
2011 ◽  
Vol 77 (12) ◽  
Author(s):  
A Haskovic ◽  
A Copra Janicijevic ◽  
A Topcagic ◽  
L Klepo ◽  
A Kapur ◽  
...  

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Dalila Lopes da Silva ◽  
Renato de Mello Prado ◽  
Luis Felipe Lata Tenesaca ◽  
José Lucas Farias da Silva ◽  
Ben-Hur Mattiuz

AbstractCalcium (Ca) deficiency in cabbage plants induces oxidative damage, hampering growth and decreasing quality, however, it is hypothesized that silicon (Si) added to the nutrient solution may alleviate crop losses. Therefore, this study aims at evaluating whether silicon supplied in the nutrient solution reduces, in fact, the calcium deficiency effects on cabbage plants. In a greenhouse, cabbage plants were grown using nutrient solutions with Ca sufficiency and Ca deficiency (5 mM) without and with added silicon (2.5 mM), arranged as a 2 × 2 factorial in randomized blocks, with five replications. At 91 days after transplanting, the plants were harvested for biological evaluations. In the treatment without added Si, Ca deficiency promoted oxidative stress, low antioxidant content, decreased dry matter, and lower quality leaf. On the other hand, added Si attenuated Ca deficiency in cabbage by decreasing cell extravasation while increasing both ascorbic acid content and fresh and dry matter, providing firmer leaves due to diminished leaf water loss after harvesting. We highlighted the agronomic importance of Si added to the nutrient solution, especially in crops at risk of Ca deficiency.


1987 ◽  
Vol 67 (1) ◽  
pp. 331-335
Author(s):  
HAK-YOON JU ◽  
W. JOHN MULLIN

The ascorbic acid (vitamin C) content of fresh imported field tomatoes and Nova Scotia greenhouse and field tomatoes was determined on a bi-weekly basis during the period of availability of each type of tomato to the Nova Scotia consumer in 1984. The average ascorbic acid contents of imported and Nova Scotia field and greenhouse tomatoes were 13.3, 16.7 and 17.7 mg 100 g−1 fresh weight, respectively. A study of nine recommended or promising field tomatoes for the Atlantic region showed significant differences in ascorbic acid content among the cultivars. The cultivar Quick Pick had the highest ascorbic acid content of 22.5 ± 1.5 mg 100 g−1, the cultivar Campbell 18 had the lowest content, 12.0 ± 2.9 mg 100 g−1. In Dombito greenhouse tomatoes the stage of maturity and the effect of cluster location were tested against ascorbic acid content. The lowest ascorbic acid content of 9.1 ± 1.0 mg 100 g−1 was found with the small green tomatoes while others from mature green to overripe contained 14.0–16.7 mg 100 g−1. Tomatoes from different cluster locations showed no significant difference in ascorbic acid content.Key words: Vitamin C, L-ascorbic acid, tomatoes


2015 ◽  
Vol 2015 ◽  
pp. 1-7 ◽  
Author(s):  
Vijendren Krishnan ◽  
Syahida Ahmad ◽  
Maziah Mahmood

Plants from Gynura family was used in this study, namely,Gynura procumbensandGynura bicolor.Gynura procumbensis well known for its various medicinal properties such as antihyperglycaemic, antihyperlipidaemic, and antiulcerogenic; meanwhile,G. bicolorremains unexploited. Several nonenzymatic antioxidants methods were utilized to study the antioxidant capacity, which include ferric reducing antioxidant power (FRAP), 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay, total flavonoid content, total phenolic content, and ascorbic acid content determination. DPPH assay revealsG. procumbensshoot as the lowest (66.885%) andG. procumbensroot as the highest (93.499%) DPPH radical inhibitor. In FRAP assay, reducing power was not detected inG. procumbensleaf callus (0.000 TEAC mg/g FW) wherebyG. procumbensroot exhibits the highest (1.103 TEAC mg/g FW) ferric reducing power. Total phenolic content and total flavonoid content exhibited similar trend for both the intact plants analysed. In all antioxidant assays,G. procumbenscallus culture exhibits very low antioxidant activity. However,G. procumbensroot exhibited highest phenolic content, flavonoid content, and ascorbic acid content with 4.957 TEAC mg/g FW, 543.529 QEµg/g FW, and 54.723 µg/g FW, respectively. This study reveals thatG. procumbensroot extract is a good source of natural antioxidant.


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