HM Iftekhar Alam
Biotechnology and Genetic Engineering Discipline, Khulna University, Khulna 9208, Bangladesh
Anirban Biswas
Biotechnology and Genetic Engineering Discipline, Khulna University, Khulna 9208, Bangladesh
M Zakir Hosen
Biotechnology and Genetic Engineering Discipline, Khulna University, Khulna 9208, Bangladesh
M Rabiul Islam
Biotechnology and Genetic Engineering Discipline, Khulna University, Khulna 9208, Bangladesh
Sheikh Julfikar Hossain
Biotechnology and Genetic Engineering Discipline, Khulna University, Khulna 9208, Bangladesh
Antioxidant, Fruits, Polyphenols, Reducing power, Nanoparticles
Biotechnology and Genetic Engineering Discipline, Khulna University, Khulna 9208, Bangladesh
Quality and Nutrition
The mature fruits of Aegle marmelos L. (wood apple), Ananas sativus L. (pineapple), Annona reticulata L. (custard apple), Artocarpus heterophyllus Lam. (jackfruit), Artocarpus lacucha Buch.-Ham. (monkey fruit), Averrhoa bilimbi L. (bilimbi), Averrhoa carambola L. (star fruit), Baccaurea ramiflora Lour. (burmese grape), Borassus flabellifer L. (palm), Carica papaya L. (papaya), Carissa carandas L. (green karanda), Citrus aurantifolia L. (lime), Citrus maxima Merr. (pomelo), Cocos nucifera L. (coconut), Dillenia indica L. (elephant apple), Dimocarpus longan Lour. (longan), Diospyros blancoi L. (velvet apple), Emblica officinalis L. (indian gooseberry), Ficus carica L. (fig), Garcinia cowa Roxb. (mangosteen), Limonia acidissima L. (sour wood apple), Litchi chinensis Sonn. (lychee), Mangifera indica L. (mango), Manilkara zapota L. (sapodila), Olea europeae L. (olive), Phoenix sylvestris (L.) Roxb. (date palm), Phyllanthus acidus L. (Malay gooseberry), Psidium guajava L. (guava), Spondias mombin L. (golden apple/hog palm), Syzygiun cumini L. (java palm), Syzygium samarangense (Blume) Merr. and L.M. Perry (wax apple), Tamarindus india L. (tamarind), and Ziziphus jujube Mill. (jujube) were collected from the different parts of Bangladesh from January to December 2016. After the collection, edible parts of the fruits were separated and shed dried. Then, each dried sample was pulverized with a grinder machine and stored in air-tight containers at room temperature. Ten grams of powder of each fruit were taken in a separate airtight bottle. Then, 200 ml of methanol and ethanol mixture (1: 1) was added to each bottle. The mixtures were vigorously shaken and kept at 30°C, 20 hrs, 150 rpm. Then the mixtures were filtered through Whatman no. 1 filter paper and the filtrates were air-dried, and after adjustment of volumes, the extracts were kept in a refrigerator at 4oC. The total concentration of polyphenols (TP) in the extracts was determined according to Folin-Ciocalteu’s method (Ough and Amerine 1988) with gallic acid (GA) as the standard. The total flavonoids content (Zhishen et al. 1999), DPPH free radicals scavenging activity (Blois 1958), reducing power (Oyaizu 1986), and total antioxidant capacity (Prieto et al. 1999) were determined colorimetrically. For AgNPs biosynthesis, 4 g of powder of each fruit was extracted with an 80 ml mixture of ethanol and methanol (1: 1) and mixed thoroughly. The mixtures were incubated for 20 hrs in a shaking incubator at 30°C and at 150 rpm. Then the supernatant was collected after centrifugation for 10 min at 3000 rpm. The collected supernatants were dried at room temperature and the volume was adjusted using distilled water. The extract was mixed with 1mM AgNO3 until the volume reached 2.5 ml. The mixture was incubated in dark in a shaking incubator for 20 hrs at 30°C and 150 rpm. After incubation, absorbance was measured at 440 nm against blank using a spectrophotometer. The content of nanoparticles was expressed as optical density (OD). Results were expressed as mean ± SD (standard deviation) for a given number of observations, n = 3-5. One-way analysis of variance was used to analyze the statistical difference. Differences with p < 0.05 were considered statistically significant.
Bangladesh J. Bot. 50(3): 445-451, 2021 (September)
Journal