Comparison of volatile profiles and bioactive components of sun-dried Pu-erh tea leaves from ancient tea plants on Bulang Mountain measured by GC-MS and HPLC

To explore the volatile profiles and the contents of ten bioactive components(polyphenols and caffeine) of sun-dried Pu-erh tea leaves from ancient tea plants on Bulang Mountain,17 samples of three tea varieties were analyzed by headspace-solid phase microextraction-gas chromatography-mass spectrometry(HS-SPME-GC-MS) and high-performance liquid chromatography(HPLC).A total of 75 volatile components were tentatively identified.Laomaner(LME),Laobanzhang(LBZ),and other teas on Bulang Mountain(BL) contained 70,53,and 71 volatile compounds,respectively.Among the volatile compounds,alcohols(30.2%-45.8%),hydrocarbons(13.7%-17.5%),and ketones(12.4%-23.4%) were qualitatively the most dominant volatile compounds in the different tea varieties.The average content of polyphenol was highest in LME(102.1 mg/g),followed by BL(98.7 mg/g) and LBZ(88.0 mg/g),while caffeine showed the opposite trend,27.3 mg/g in LME,33.5 mg/g in BL,and 38.1 mg/g in LBZ.Principal component analysis applied to both the volatile compounds and ten bioactive components showed a poor separation of samples according to varieties,while partial least squares-discriminant analysis(PLS-DA) showed satisfactory discrimination.Thirty-four volatile components and five bioactive compounds were selected as major discriminators(variable importance in projection(VIP)>1) among the tea varieties.These results suggest that chromatographic data combined with multivariate analysis could provide a useful technique to characterize and distinguish the sun-dried Pu-erh tea leaves from ancient tea varieties on Bulang Mountain.

A Comparative Study of Antioxidant Activities between Fresh and Dry Mushrooms in the Genera <i>Cantharellus</i>and <i>Afrocantharellus</i>from Tanzania

Cantharellus and Afrocantharellus mushrooms are widely consumed in both fresh and dry forms. However, their antioxidant and whether their values changing with drying processes are not known. This study establishes their values and the effect of sun drying on their quality and quantity. Methanolic extracts of five Cantharellus and two Afrocantharellus species were investigated. The investigation used (1,1-diphenyl-2-picrylhydrazyl radical) DPPH as a substrate to determine radical scavenging abilities. Further quantitative analyses for carotenoids, flavonoid, total phenolic compounds and vitamin C content were done using spectrophotometric assay at 515 nm. Comparatively, fresh mushroom had higher vitamin C and Lycopene contents than their dry counterparts with β-carotene. Flavonoid and phenolic compounds were higher in dry forms than those in their fresh counterparts. Radical scavenging ability also varied with fresh forms depicting higher activity compared to dry forms. The variation was low in Afrocantharellus species (0.8% and 0.99%) while it was higher in Cantharellus species (24.12% and 7.52%). The highest ability was observed in fresh forms of Cantharellus pseudocibarius (EC50 50 = 0.4 mg/ml) was from dry form of Cantharellus rufopunctatus. This shows that studied mushrooms are rich in antioxidants and their quality and quantities are affected differently in both forms. Both dry and fresh mushrooms are potential sources of natural antioxidants. The portrayed high scavenging ability by these mushrooms envisages promoting them into potential nutraceutics.

Differences in Browning Index and CIELAB Coordinates of the Two Grape Drying Processes, Traditional Sun-Drying and Chamber-Drying and during the Ageing of Pedro Ximenez Sweet Wine

The color parameters during the Pedro Ximenez grape raisining, as well as the sweet wine aging process from the Montilla-Moriles grapes （Andalusia, Southern Spain）, have been studied. Drying process of grapes was carried out by means of the traditional sun-drying method and an alternative chamber-drying method under 50℃. Chamber-drying allows shorter drying time and select grapes at a higher ripening degree. During raisining grape musts decreased in hab （hue angle） and increased in Cab （chroma）. In comparative terms, the final values of hue were virtually identical in both types of drying, although differences were found in the final values of chromaticity, being lower in the chamber-drying method. Changes in the color parameters during aging were compared in commercial wines with different aging systems and without aging. Likewise, as a reference of traditional wine aging system, the color changes in wines with four aging degrees were also studied. Regarding to the commercial wines studied, it can be pointed out the wine aged without blends for 4 years significantly differed in the values of hab and C＊ab of the remaining wines, which show more similar values among them and in the data obtained for the wines aged by the traditional aging system.

Effect of Seed Drying on Germination Behavior and Seedling Growth of Sweetsop （Annona squamosa）

An experiment was conducted at the Department of Horticulture, College of Agriculture and Natural Resources, Kwame Nkrumah University of Science and Technology, Kumasi （KNUST） Ghana from September, 2009 to April, 2010, to determine the most appropriate drying method, as a post harvest practice, that would ensure high percentage germination ofAnnona squamosa seeds and its subsequent effect on seedling growth. The seeds were sun-dried, air-dried under shade or kept in the fresh state. Five treatments were used, namely, Freshly Sown seeds （Treatment 1, control）, Seeds Air-Dried under Shade for one day （Treatment 2）; Seeds Sun-Dried for one day （Treatment 3）; Seeds Air-Dried under Shade for three consecutive days （Treatment 4）; Seeds Sun-Dried for three consecutive days （Treatment 5）. The experiment was arranged in a Completely Randomized Design （CRD） and replicated three times. Drying of Annona squamosa seeds had significant effect on earliness and number of seeds germinated. Air drying under shade and sun-drying for three consecutive days improved earliness to germination （26 days after sowing） and percent total germination but air-drying under shade had better effect on total seed germination, achieving 90% germination in 42 days after sowing. Furthermore, the prevailing ambient temperature of 30 ℃-32 ℃ enhanced germination of Annona squamosa seeds. The study concluded that for optimum germination, seeds of Annona squamosa should be either air-dried or sun-dried for three consecutive days and be incubated in an ambient temperature range of 30 ℃-32 ℃. In terms of growth, seedling growth in leaf production was better from seeds sun-dried for three consecutive days.