a b s t r a c tThe physicochemical properties and chemical composition of oil extracted from five varieties of plant seeds (bittermelon, Kalahari melon, kenaf, pumpkin and roselle seeds) were examined by established methods. The thermal properties of extracted oils by differential scanning calorimetry were also evaluated. Sensorial profiles of these seed oils were defined through the CieLab (L*, a*, b*) colour. Most of the quality indices and fatty acid compositions showed significant (P < 0.05) variations among the extracted oils. Physicochemical properties of the oils extracted were iodine value, 86.0-125.0 g I 2 /100 g oil; saponification value, 171.0-190.7 mg of KOH/g of oil; acid value, 1.1-12.9 mg of KOH/g of oil, free fatty acid, 0.6-6.5 g/100 g of oil, and peroxide value 1.5-6.5 meq of O 2 /kg of oil. Palmitic, oleic and linoleic acids were the major fatty acids in all of the extracted seed oils except for bittermelon, where eleostearic acid was the major fatty acid. Gallic, protocatechuic, p-hydroxybenzoic, vanillic, caffeic, syringic, pcoumaric and ferulic acids were identified in the extracted plant oils. Among these, vanillic acid was predominant in all extracted oils. The oils were rich in tocopherols with g-tocopherol as the major components in all oil samples. Among the phytosterols, sitosterol was the major phytosterol extracted from the five plant seed oils. The seeds of these plants contain a great number of valuable minor compounds, which have a potential high value as food and for production of non-food products.

The aim of the present study was to investigate the preparation of β-carotene nanodispersions as potential active ingredients for food formulations. Nanodispersions containing β-carotene were obtained by a process based on an emulsification-evaporation technique. The preparation method consisted of emulsifying an organic solution of β-carotene in an aqueous solution containing emulsifier using two different homogenizers (a conventional homogenizer and a microfluidizer), followed by direct solvent evaporation under reduced pressure. The influence of different homogenizing conditions (pressure and cycle) and two organic/aqueous phase ratios on particle size parameters and content of β-carotene was investigated. In addition, the stability of β-carotene nanodispersions was carried out at a storage temperature of 4 °C. The particle size distribution of β-carotene in nanodispersions was demonstrated with a laser diffraction particle size analyzer and the retention of βcarotene in the prepared nanodispersions was studied by high-pressure liquid chromatography. In general, homogenization pressure and cycle had significant (P < 0.05) effects on various particle size parameters. A volume-weighted mean diameter (D4,3) of βcarotene nanoparticles, ranging from 60 to 140 nm, was observed in this study.

Total phenolic content (TPC) Total flavonoid content (TFC) 2,2 0 -Azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) radical-scavenging capacity 2,2-Diphenyl-1-picrylhydrazyl (DPPH) radical-scavenging capacity a b s t r a c t An investigation into the effects of ethanol concentration (0-100%, v/v), extraction time (20-120 min) and extraction temperature (25-65°C) on the extraction of phenolic antioxidants from mengkudu (Morinda citrifolia) was performed using a single-factor experiment. Total phenolic content (TPC) and total flavonoid content (TFC) assays were used for determination of phenolic compounds. Antioxidant capacity was evaluated by measuring the scavenging effect on 2,2 0 -azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) and 2,2 0 -diphenyl-1-picrylhydrazyl (DPPH) radicals. Experimental results showed that extraction conditions had significant effect on extraction of phenolic compounds and antioxidant capacities. The optimised conditions were 40% ethanol for 80 min at 65°C, with values of 919.95 mg GAE/100 g DW for TPC, 472.73 mg CE/100 g DW for TFC, 791.71 lmol TEAC/100 g DW for ABTS and 1928.5 lmol TEAC/100 g DW for DPPH. TPC was significantly correlated with DPPH under the effects of ethanol concentration (r = 0.932) and extraction time (r = À0.938).