الفهرس 
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Abstract
This study was conducted to assess the effect of germination on radicle length of legumes as well as melatonin content, total phenols, total flavonoids and antioxidant activities of legume fractions. The effect of cooking and cooking followed by storage at 5ºC and -20ºC on melatonin content in legumes was evaluated. Heat and pH stability as well as storage stability in dark and light at room temperature on antioxidants activity of some herbs rich in melatonin content as compared with melatonin were evaluated. The effect of soaking in hot water (60-95oC) for different time on the melatonin, total phenols, total flavonoids and antioxidant activity of herbal and turmeric teas were also evaluated.
The obtained results can be summarized as follows:
6.1. Melatonin, total phenols, total flavonoid and antioxidant activity of raw legumes
Melatonin content of raw broad bean, lupine, chickpea, black lentil, fenugreek and common bean were 4.43, 16.47, 24.42, 4.79, 54.22 and 5.85ng/g, respectively. Total phenols of raw broad bean, lupine, chickpea, black lentil, fenugreek and common bean were 5.04,
5.38, 5.68, 5.21, 5.79 and 4.50mg gallic acid/g, respectively. Total flavonoid of raw broad bean, lupine, chickpea, black lentil, fenugreek and common bean were 4.31, 2.62, 8.43, 5.56, 8.86 and 4.33mg quercetin/ g. Antioxidant activity of raw broad bean, lupine, chickpea, black lentil, fenugreek and common bean were 92.67, 86.70, 90.32, 87.68 and 84.52%, respectively.
6.2. Phenolic compounds in legumes
The most abundant phenolic compounds in raw broad bean, lupine, chickpea, black lentil, fenugreek and common bean and were Iso-ferulic (48 ppm), chlorogenic (43 ppm) and oleuropin (23 ppm); Pyrogallol (185 ppm), caffeine (99 ppm) and e-vanillic (81 ppm); protocatecoic (156 ppm), gallic (30 ppm) and e-vanillic (24 ppm); p-Hydroxy-benzoic (99 ppm) and oleuropin (15 ppm); Oleuropin (300 ppm), caffeine (253 ppm) and e-vanillic (248 ppm) and Pyrogallol (224 ppm) and e-vanillic (16 ppm), respectively.
6.3. Flavonoid compounds in legumes
The main flavonoid compounds in raw broad bean, lupine, chickpea, black lentil, fenugreek and common bean were rutin (7.85 ppm), hesperdin (3.45 ppm) and naringin (2.57); hesperdin (247.22
ppm), quercetrin (47.40 ppm) and naringin (16.65 ppm); 7 oh-flav (3.29 ppm), hespertin (2.98 ppm) and naringin (2.86 ppm); hespertin (26.60 ppm), rutin (11.30 ppm) and naringin (6.98 ppm); hespertin (22.94 ppm), naringin (20.83 ppm) and rosemarinic (16.23 ppm) and. Hesperdin (13.0 ppm), naringin (9.36 ppm), 7 oh-flav (8.37 ppm), and hespertin (8.04 ppm), respectively.
6.4. Radical length of germinated legumes
Radical length of legumes was increased by increasing germination time. At the sixth day of germination, radical length of legumes were increased in the following order common bean (4.20) < lentil (4.27) < broad bean (5.50) < chickpea (6.63) < fenugreek (7.30) < lupine (8.50 cm).
6.5. Melatonin content of germinated legumes
Melatonin contents of legume cotyledons, radicals and hulls were significantly (p ≤ 0.05) increased as germination time progressed. At the sixth day of germination, mean melatonin content of legumes was increased in the following order 386.26% for cotyledons, 261.98% for radicals and 183.22% for hulls as compared with the third day of germination. Melatonin contents of chickpea seeds were much higher
in the cotyledons (54.46-471.49 ng/g), than in the radicals (28.86-100.56 ng/g) and hulls (10.44-21.05 ng/g) throughout germination time. Lupine and lentil seed fractions had similar trend, although their melatonin contents were much lower. Melatonin contents of common beans were much higher in the radicals (144.27-432.31 ng/g), than in the cotyledons (63.72-208.96 ng/g) and hulls (10.18-12.07 ng/g) throughout germination time. Similar trend was observed for broad beans. However, melatonin contents of fenugreek seeds were higher in the hulls (96.41-290.08 ng/g) than in the cotyledons (73.20-161.95 ng/g) and radicals (18.54-154.4 ng/g).
6.6. Total phenols of germinated legumes
Total phenol contents of legume cotyledons, radicals and hulls were significantly (p ≤ 0.05) increased by increasing germination time. At the sixth day of germination, mean total phenol content was increased in the following order 61.68% for radicals (5.40 mg gallic acid/g), 41.65% for hulls (5.51 mg gallic acid /g) and 39.72% for cotyledons (8.83 mg/g gallic acid) as compared with the third day of germination (3.34, 3.89 and 6.32 mg gallic acid/g, respectively).
6.7. Total flavonoid of germinated legumes
Total flavonoid contents of legume cotyledons, radicals and hulls were significantly (p ≤ 0.05) increased by increasing germination time. At the sixth day of germination, mean total flavonoid content was increased in the following order 134.88% for hulls (3.03 mg quercetin/g), 85.43% for radicles (3.69 mg quercetin/g), and 63.64% for cotyledons (10.08 mg quercetin /g) as compared with the third day of germination (1.29, 1.99 and 6.16 mg quercetin/g, respectively).
6.8. Antioxidant activity of germinated legumes
Antioxidant activities of legume cotyledons, radicals and hulls were significantly (p ≤ 0.05) increased by increasing germination time.At the sixth day of germination, mean total antioxidant activity was increased in the following order 24.49% for hulls (89.12%), 16.76% for radicals (96.82%), and 7.73% for cotyledons (97.40%) as compared with the third day of germination (71.59, 82.92 and 90.41%, respectively).
6.9. Sensory properties of legumes after six day of germination
No significantly (p > 0.05) differences in overall acceptability scores were observed among legumes except for chickpea seeds. Although overall acceptability rating score of chickpea seeds was lower (p ≤ 0.05) than other legumes, it had rating score described as like slightly (6.5). However, other legumes had rating scores ranged between like moderately and like very much (7.35-8.05).
6.10. Melatonin in cooked legumes
Cooking process reduced melatonin contents of broad bean, lupine, chickpea, black lentil, fenugreek and common bean by 77.65, 47.94, 43.89, 62, 14.24 and 77.09%, respectively.
6.11. Melatonin of cooked legumes as affected by storage at ~5˚C
Melatonin content was gradually decreased (p ≤ 0.05) during cold storage. The mean reduction of melatonin contents were 31.32, 47.23, 56.76, 69.94 and 74.83% for 1, 2, 3, 4 and 5 week of cold storage, respectively. After 5 weeks of storage at ~5˚C, melatonin contents of broad bean, lupine, chickpea, black lentil, fenugreek and common bean were reduced by 93.23, 82.82, 89.31, 93.74, 62.91 and 94.87%, respectively.
6.12. Melatonin of cooked legumes as affected by storage at -20˚C
Melatonin content was gradually decreased (p ≤ 0.05) during storage at -20˚C. The mean reduction of melatonin contents were 33.81, 44.42, 49.32, 56.45 72.73 and 82.31% for 1, 2, 3, 4, 5 and 6 months of storage at -20˚C, respectively. After 6 months of storage at -20˚C, melatonin contents of broad bean, lupine, chickpea, black lentil, fenugreek and common bean were reduced by 95.26, 93.93, 73.37, 79.12, 81.34 and 94.87%, respectively.
6.13. Phenolic compounds of herbs and turmeric
The most abundant phenolic compounds in sage, thyme, chamomile, peppermint and turmeric were benzoic (176 ppm), resveratrol (98 ppm) and salicylic (76 ppm); oleuropin (10846 ppm), 3,4,5 methoxy cinnamic (1153 ppm) and e-vanillic (1034 ppm); 3,4,5 methoxy cinnamic (3607 ppm), ellagic (1646 ppm) and e-vanillic (1145 ppm); e-vanillic (81566 ppm), oleuropin (967 ppm) and benzoic acid (686 ppm) and Iso-ferulic (701 ppm), 3,4,5 methoxy cinnamic (490 ppm) and vanillic (184 ppm), respectively.
6.14. Flavonoid compounds of herbs and turmeric
The most abundant flavonoid compounds in sage, thyme, chamomile, peppermint and turmeric were hespertin (1079 ppm), rosemarinic (521 ppm) and hesperdin (391 ppm); naringin (5407 ppm), hespertin (1079 ppm) and rutin (901 ppm); hespertin (2735 ppm), naringin (2291 ppm) and rutin (381 ppm); rosemarinic (3225 ppm), quercetin (229 ppm) and naringin (175 ppm) and 7 oh-flav (4552 ppm), quercetin (263 ppm) and rosemarinic (78 ppm), respectively.
6.15. Effect of solvent types on antioxidant activities of herbs, turmeric and melatonin
Melatonin (94.96%) had higher (p ≤ 0.05) mean antioxidant activity than those of herb and turmeric extracts (68.84-81.41%). Chamomile (81.41%), thyme (77.88%) and peppermint (76.23%) had the highest (p ≤ 0.05) mean antioxidant activities among turmeric and herbs however sage (68.84%) showed the lowest one value. The highest (p ≤ 0.05) mean antioxidant activity level was obtained by 100% methanol (93.95%) followed by 50% methanol (77.80%) and water
6.16. Heat stability of antioxidant
Antioxidant activities of chamomile (70.93%) followed by peppermint (69.47%) extracts were more (p ≤ 0.05) stable when incubated at 30-80˚C than turmeric and other herb extracts. However, sage (58.30%) extract had the lowest (p ≤ 0.05) antioxidant activity among herb and turmeric extracts. Increasing the incubation temperature time from 30 to 60 min resulted in a significant (p ≤ 0.05) decrease in the antioxidant activity of turmeric, herb and melatonin extracts. Antioxidant activities of herb, turmeric and melatonin extracts were reduced by 3.08, 7.61, 11.17, 17.28 and 27.36% when incubated at 40, 50, 60, 70 and 80°C, respectively as compared with incubation at 30°C.
6.17. pH stability of antioxidant
Extract with pH 4.0 (61.52%) was higher (p ≤ 0.05) in the antioxidant activity than the extracts with other pH values. There was no significant difference (p> 0.05) in the mean antioxidant activity between extracts with pH 4.5 (59.79%) and pH 6.0 (59.49%) and extracts with pH 5.5 (53.40%) and pH 6.5 (53.78%). Antioxidant activity of extracts was gradually decreased (p ≤ 0.05) till pH 5.5 and
increased at pH 6.0 followed by decrease (p ≤ 0.05) at higher pH values.
6.18. Storage stability in the dark and light of antioxidant
Antioxidant activities of herb, turmeric and melatonin extracts were gradually reduced by storage in the dark or light at room temperature. After 4 week of storage, the reduction in antioxidant activity was 15.67% and 22.43% for dark and light, respectively.
6.19. Melatonin of raw herbs, turmeric, herbal teas and turmeric tea
Chamomile (1224.62 ng/g) and thyme (232.55 ng/g) had much higher (p ≤ 0.05) melatonin contents than those of turmeric and other herbs. Turmeric had higher melatonin content than peppermint and sage. Melatonin contents of herbal and turmeric teas were significantly (p ≤ 0.05) increased as the time of soaking in hot water progressed. After 10 min of soaking in hot water, 93.86% of melatonin content was leached into soaking water. Non-significant (p > 0.05) difference in mean melatonin content was observed between sage tea and peppermint tea. Chamomile tea (784.84 ng/g) followed by thyme tea (184.42 ng/g) had much higher (p ≤ 0.05) mean melatonin contents
than those of other herbal and turmeric teas. On the other hand, turmeric tea had higher (p ≤ 0.05) mean melatonin content (72.47 ng/g) than sage tea (38.28 ng/g) and peppermint tea (39.43 ng/g).
6.20. Total phenols of raw herbs, turmeric, herbal teas and turmeric tea
Total phenol contents of sage, thyme, chamomile, peppermint and turmeric were 55.08, 54.19, 55.30, 53.97 and 54.51 mg gallic acid/g samples, respectively. Total phenols contents of herbal teas and turmeric tea were significantly (p ≤ 0.05) increased as the time of soaking in hot water progressed. After 10 min of soaking in hot water, 92.13% of total phenol content was leached into soaking water. Sage tea (52.59mg gallic acid/g sample) followed by chamomile tea (46.16mg gallic acid/g sample) had much higher (p ≤ 0.05) mean total phenol contents than those of other herbal teas and turmeric tea. On the other hand, thyme tea had higher (p ≤0.05) mean total phenol content (44.91mg gallic acid/g sample) than turmeric tea (43.48mg gallic acid/g sample) and peppermint tea (39.79mg gallic acid/g sample).
6.21. Total flavonoids of raw herbs, turmeric, herbal teas and turmeric tea
Total flavonoid contents of sage, thyme, chamomile, peppermint and turmeric were 15.19, 26.54, 4.33, 10.64 and 3.21 mg quercetin/g sample, respectively. Total flavonoid contents of herbal teas and turmeric tea were significantly (p ≤ 0.05) increased as the time of soaking in hot water increased. After 10 min of soaking in hot water, 57.85% of total flavonoid content was leached into soaking water. Thyme tea (10.15 mg quercetin/g sample) followed by peppermint tea (6.18mg quercetin/g sample) had much higher (p ≤ 0.05) mean total flavonoid contents than those of other herbal teas and turmeric tea. On the other hand, sage tea had higher (p ≤ 0.05) mean total flavonoid content (5.78mg quercetin/g sample) than chamomile tea (2.39mg quercetin/g sample) and turmeric tea (1.88mg quercetin/g sample).
6.22. Antioxidant activity of raw herbs, turmeric, herbal teas and turmeric tea
Total antioxidant activities of sage, thyme, chamomile, peppermint and turmeric were 55.27, 74.35, 72.52, 68.30 and 23.76%, respectively. Antioxidant activity of herbal and turmeric teas were significantly (p ≤ 0.05) increased as the time of soaking in hot water increased. After 10 min of soaking in hot water, 96.21% of antioxidant activity content was leached into soaking water. Chamomile tea
(67.56%) followed by thyme tea (53.64%) had much higher (p ≤ 0.05) mean antioxidant activity than those of other herbal and turmeric teas. On the other hand, peppermint tea had higher (p ≤ 0.05) mean antioxidant activity (52.96%) than sage tea (46.63%) and turmeric tea (20.33%).
6.23. Sensory properties of herbal and turmeric teas
Sage tea and turmeric tea had taste rating scores described as like slightly (6.78-6.94). Thyme tea and chamomile tea had taste rating scores described as like moderately (7.08-7.64). However, peppermint tea had taste rating scores described as like very much (8.02). Odor, color and overall acceptability of herbal and turmeric teas were not (p > 0.05) affected by herbs types and turmeric. On the other hand, sensory properties of herbal and turmeric teas were not (p > 0.05) affected by soaking time in hot water.