Antioxidant activities of different aerial parts of putat (Barringtonia racemosa L.)

The antioxidant activities of methanolic, ethanolic and boiling water extracts of Barringtonia racemosa leaves, sticks, and barks were studied and their contents of total phenolics, flavonoids and carotenoids were measured. Methanolic extracts of aerial parts of the plant contained relatively higher levels of total phenolics than other extracts (leaf: 16.2 ± 0.02 mg gallic acid equivalent/g freeze dried-weight (FDW) tissue, stick: 29.9 ± 0.02 mg gallic acid equivalent/g FDW tissue, bark: 21.78 ± 0.20 mg gallic acid equivalent/g FDW tissue). The ethanolic extracts in aerial parts gave higher levels of total flavonoid (leaf: 38.55 ± 2.75 mg rutin/g FDW tissue, stick: 40.72 ± 5.91 mg rutin/g FDW tissue, bark: 68.29 ± 9.63 mg rutin/g FDW tissue). The amounts of β-carotene and lycopene were found higher in methanolic and ethanolic extracts of the leaf (342.2 ± 8.79 μg β-carotene/g FDW tissue, 77.38 ± 4.61μg lycopene/g freeze dried-weight tissue; 356.9 ± 0.93 μg β-carotene/g FDW tissue, 99.3 ± 5.29 μg lycopene/g FDW tissue,respectively). The methanolic and ethanolic extracts in all aerial parts tested exhibited very strong antioxidant properties when compared to butylated hydroxytoluene (BHT), ascorbic acid and α-tocopherol in the free radical scavenging and reducing power assays

The Effect of Dosage and Storage Time on the Formation of Bound Residues in Paddy, Milled Rice and Maize

Stored unmilled rice (paddy), milled rice and maize treated with radiolabelled malathion formed bound 14C residues. After 3 months of storage, the bound residues in the grains treated with 10J.Lg/g malathion accounted for 10.8, 6.5 and 13.3% of the applied dose in paddy, rice and maize respectively. After 6 months, the corresponding values of bound residues were 14.2, 4 and 17.7% respectively. Increasing the dosage of malathion to 50J.lg/ g does not significantly increase the percentage of the bound residues formed. However, the absolute amount increased by more than 410ld in all the grains tested

Establishment of Physalis minima hairy roots culture for the production of physalins

This report describes the technique used to induce the hairy roots in Physalis minima (Linn.). Different types of explants obtained from in vitro germinated seedlings were aseptically co-cultivated with A. rhizogenes strain LBA9402 in different media. Root growth and production of physalins were investigated in various basal media grown under dark and light conditions, and compared to that of normal root cultures. Transformed hairy root cultures grew rapidly and reach stationary phase after 15 days on a B5 medium. HPLC analysis of extracts of hairy root cultures showed that the maximum content of physalin B and F was 1.82 and 4.15 mg g-1 DW, respectively, when grown under dark conditions. Normal root cultures produced higher physalin B (1.60-1.62 mg g-1 DW) and F (3.30-3.75 mg g-1 DW) under the same culture conditions. Physalin F synthesis in light-grown root cultures was reduced significantly

Effect of elicitors on the production of naringin and rutin in leech lime (Citrus hystrix) callus

Treatment of Citrus hystrix callus with various types of elicitors decreased the callus growth as the concentration of elicitors increased. However, callus growth remained relatively constant at 0.05% (w/v) alginate and slightly increased to 1.30 ± 0.04 g dwt./culture at 0.1% (w/v) alginate. Analysis of the flavonoids using high performance liquid chromatography (HPLC) showed that only naringin and rutin were produced. Maximum production of naringin (12.13 ± 0.07 mg/g dwt.) and rutin (3.09 ± 0.05 mg/g dwt.) (p ≤ 0.05) was found in callus treated with 0.5% (w/v) agarose

Effect of NAA, kinetin and three elicitors on the growth and production of flavour compounds from leech lime (Citrus hystrix) calli

Treatment of the leech lime (Citrus hystrix) callus with 1.0 mg/L (w/v) kinetin exhibited the maximum growth (0.415 ± 0.09 g fwt.) compared to all treatments with naphthaleneacetic acid (NAA). Analysis using gas chromatography (GC) showed that treatment with kinetin inhibited the synthesis of flavour compounds. On the other hand, treatment with 5.0 mg/L (w/v) NAA gave the highest production of cyclohexanol (4.16 ± 0.03 μg/g fwt.), p-cymene (5.13 ± 0.98 μg/g fwt.) and limonene (1.83 ± 0.19 μg/g fwt.). Addition of various concentrations of individual elicitors such as yeast extract and agarose into the medium decreased the callus growth. However, treatment of callus with 0.3% (w/v) alginate resulted in higher callus growth (0.88 ± 0.1 g fwt.) compared to control. Among the three different elicitors tested, only treatment with yeast extract was able to increase the number of flavour compounds and two new compounds were synthesised compared to the control. The quantities of flavour compounds produced also varied depending on the concentration of elicitor used

Analysis of flavour compounds in leech lime (Citrus hystrix) flower and yield improvement in callus

The major flavour compound obtained from Citrus hystrix flower was citronellal. Plantlet grown on a basal Murashige and Skoog (MS) medium without phytohormone do not produce any citronellal. However, the quantity of limonene was remarkably higher (101.62 ± 5.24 μg/g fwt.) in stem than petal (27.30 ± 1.42 μg/g fwt.), ovary (10.76 ± 0.01 μg/g fwt.) and pollen and anther (6.64 ± 0.24 μg/g fwt.). Callus was successfully induced from stem, embryo and petiole on the MS medium supplemented with sucrose (30 g/litre), naphthalene acetic acid (NAA) (2.0 mg/litre) and kinetin (1.0 mg/litre) but only limonene and cyclohexanol have been produced. Treatment of callus derived from stem under different types of light did not increase the number of flavour compounds. Treatment of callus under bright white cool fluorescent light showed the highest production of cyclohexanol (14.1 ± 1.11 μg/g fwt.) and limonene (1.48 ± 0.09 μg/g fwt.) compared to that of other treatments

Antioxidative activity and total phenolic compounds of leaf, root and petiole of four accessions of Centella asiatica (L.) Urban

Antioxidative activity and total phenolic compounds of root, leaf and petiole of four accessions of Centella asiatica (L.) Urban, namely CA 01, CA 05, CA 08 and CA 11, were evaluated. Antioxidative activity of the extracts was measured using the ferric thiocyanate (FTC) method and thiobarbituric acid (TBA) test. The antioxidative activities were then compared with that of α-tocopherol (natural antioxidant) and butylated hydroxytoulene or BHT (synthetic antioxidant). The results showed that CA 01 and CA 05 had the highest antioxidative activities among the accessions tested. Results also showed that both leaf and root of C. asiatica had high antioxidative activity, which was as good as that of α-tocopherol. The total phenolic content, determined according to the Folin–Ciocalteu method, varied from 3.23 to 11.7 g/100 g dry sample, and showed strong association (r2=0.90) with antioxidative activity. The results suggest that phenolic compounds are the major contributors to the antioxidative activities of C. asiatica