Antioxidant Properties and Potentiality of Silver Nanoparticles Biosynthesis of Thirty-Five Edible Bangladeshi Fruits

A comparison of total polyphenols (TP) and flavonoids (TF) contents, antioxidant activity, and silver nanoparticles (AgNPs) biosynthesis potentiality of 35 common edible fruits in Bangladesh were studied. Among the fruits, Emblica officinalis showed the highest content of TP (89 mg gallic acid equivalent (GAE)/g powder), reducing power (OD, 1.98 at 1 mg powder/ml), and 2,2-diphenyl-1-picrylhydrazyl (DPPH)-free radical scavenging activity (95.6% at 0.5 mg powder/ml) whereas the highest content (17.3 mg (+)-catechin equivalent (CE)/g powder) of TF was recorded in Garcinia cowa. The inhibitory concentration 50 (IC50) for DPPH-free radical scavenging of Annona reticulata, E. officinalis, G. cowa, Phoenix sylvestris, Psidium guajava and Syzygium cumini were 180, 21.8, 172, 188.9, 162.4 and 176.2 μg powder/ml, respectively. Litchi chinensis showed the highest total antioxidant capacity (79 mg GAE/g powder) followed by E. officinalis (69 mg GAE/g powder). The fruits showed a very strong correlation (r2 = 0.99) between TP and reducing power. P. guajava showed the highest potentiality (OD, 0.74 at 10 mg powder/ml) in the biosynthesis of AgNPs followed by S. cumini, A. reticulata and P. sylvestris. Therefore, most potential five fruits should be graded as E. officinalis > S. cumini > P. guajava > A. reticulata > P. sylvestris. Bangladesh J. Bot. 50(3): 445-451, 2021 (September)

Impact of different drying methods on nutritional quality of Garcinia cowa and Garcinia pedunculata fruits

Aim: The present study was undertaken to establish a suitable drying process for Garcinia cowa and Garcinia pedunculata fruits for maximum retention of their nutritional qualities. Methodology: Slices of three different thickness with 0.3, 0.6, 0.9 cm of G. cowa and G. pedunculata fruits were dried by sun drying, solar drying and by cabinet drying at three different temperatures (50°C, 70°C and 90°C). Results: The mean crude fat and ash content were higher in G. cowa than G. pedunculata while later was found rich in crude protein and Fe contents. Total phenol content ranged between 881.31-888.65 and 719.00-736.74 mg gallic acid equivalent 100 g-1, total flavonoid content between 89.21-90.06 and 51.00-52.54 mg quercetin equivalent 100 g-1 and mean HCA contents ranged between 3.13-3.92% and 1.84-1.99% for G. cowa and G. pedunculata, respectively. The methanolic extracts exhibited significant antioxidant activity. With lower IC50 values, G. cowa had higher antioxidant activity than G. pedunculata. Interpretation: Oven drying at 50°C and 0.9 cm slice thickness for drying resulted in better retention of total phenolic and flavonoid contents with better antioxidant activities.

XANTHONES AND OTHER COMPOUNDS FROM THE LATEX OF GARCINIA COWA

From our ongoing study on the latex of Garcinia cowa Roxb. ex Choisy collected in Quy Chau, Nghe An province, seven compounds were isolated including four prenylated xanthones: norcowanin (1), kaennacowanol A (2), garcinone D (3), fuscaxanthone I (4); one tocotrienol: parvifoliol F (5) and two triterpenes: stigmasterol (6), lupeol (7). The structures of the isolated compounds were elucidated by physico-chemical spectroscopic analysis and by comparison with reported data. To the best of our knowledge, garcinone D (3), fuscaxanthone I (4) and parvifoliol F (5) were first reported as components of Garcinia cowa.

Effect of asam kandis (Garcinia cowa Roxb) extract in drinking water on egg quality of Japanese quail (Coturnix coturnix japonica)

Asam kandis (Garcinia cowa Roxb) fruit has been reported to contain phytochemicals such as xanthon, hydroxy cytric acid and flavonoids that have various activities such as antimicrobial and antioxidant. This study was aimed to investigate the effect of asam kandis extract addition in drinking water on the quality of quail eggs. Ninety nine laying quails of 59 days of age were divided into 3 treatments and 3 replications with 11 laying quails in each replication. Completely Randomized Design was used and the treatments were: T1= control (drinking water without asam kandis extract), T2= drinking water with asam kandis extract at pH 4, T3= drinking water with asam kandis extract at pH 3. The parameters observed were egg weight, egg shape index, yolk color, yolk percentage, albumen percentage, eggshell percentage, shell thickness, and haugh unit score. The data obtained were analyzed by Analysis of Variance (ANOVA) and significant differences among treatments means were tested by Duncans multiple test. The the addition of asam kandis extract did not affect (P0.05) on egg weight, egg shape index, yolk color, yolk percentage, albumen percentage, eggshell percentage, and haugh unit score. The addition of asam kandis extract in drinking water at pH 3 significantly (P0.05) increased eggshell thickness compare to that of other treatments. The conclusion was the addition of asam kandis extract in drinking water at pH 3 increased eggshell thickness without decreasing egg quality.

A REVIEW ON CYTOTOXIC ACTIVITY OF (GARCINIA COWA ROXB.): POTENTIAL AS AN ANTICANCER

Cancer is a disease of abnormal body tissue cells that turn malignant. From the data, it can be seen that new cases and the death rate from cancer continues to increase every year so that efforts are made in the search for new anticancer agents for the prevention and treatment of cancer. There are many natural ingredients that can be used for its benefits, one of which is the Asam Kandis plant (Garcinia cowa Roxb.) This plant is rich in phytochemicals. It can be an important source of natural cytotoxic compounds and has potential as an anticancer. The analysis showed that the extract or compound from the roots, bark, twigs, leaves, and fruit rind of Asam Kandis (Garcinia cowa Roxb.) has good cytotoxic activity and is active against cancer cell lines so that it can help in the development of cancer therapy.