Melissopalynological Analysis of Honey from French Guiana.

Beekeeping directly depends on the floral biodiversity available to honey bees. In tropical regions, where nectar and pollen resources are numerous, the botanical origin of some honey is still under discussion. A precise knowledge of plants foraged by honey bees is useful to understand and certify the botanical origin of honey. In this study, attention was paid to honey samples from the French Guiana Atlantic coast where beekeepers generally place their hives in four types of biotopes: seaside vegetation, mangrove, savannah, and secondary forest. Pollen analysis of 87 honey samples enabled the identification of major plants visited by Africanized honey bees during the dry season (approximately from July to January). Through melissopalynologic analysis, 51 pollen types were identified and classified according to their relative presence. Frequently observed pollens (with relative presence > 50%) in French Guiana kinds of honey were those from Mimosa pudica, Cocos sp., Rhyncospora sp., Avicennia germinans, Paspalum sp., Spermacoce verticillata, Tapirira guianensis, Cecropia sp., Myrtaceae sp., Mauritia flexuosa sp., Solanum sp., and Protium sp. In many honeys, only M. pudica was over-represented (relative frequency > 90%). Color and electrical conductivity in French Guiana honeys exhibit significant variations, with color ranging from 27 mm to 110 mm Pfund, and electrical conductivity ranging from 0.35 to 1.22 mS/cm.

French Guiana honeys from the Amazon biome: First description of volatile fraction and antioxidant capacity.

Various honeys from French Guiana were collected and analyzed to investigate their volatile fraction composition and antioxidant activity. Volatile composition was assessed using HS-SPME/GC, GC-MS technique. Oxygenated monoterpenes like hotrienol (0.5-45.3%) were found as major molecules, followed by non terpenic compounds like phenylacetaldehyde (0.8-18.2%) or 3-hydroxy-4-phenyl-2-butanone (0.1-29.3%). Three chemical groups using statistical analysis were classified within investigated honey samples: norisoprenoids/shikimates, mevalonate and their combination. Total phenolics content (TPC) was determined by Folin-Ciocalteu method. Antioxidant activity was assessed by oxygen radical absorbance capacity (ORAC) and 2,2'-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS) assays. TPC and anti-radical activity were compared with multifloral honeys from neighboring regions, indicating the possible presence of compounds from the polyphenol family. These results are promising for further biological studies involving honeys from French Guiana.

Long-term exposure to ambient fine particles associated with asthma: A cross-sectional study among older adults in six low- and middle-income countries.

BACKGROUND: Ambient PM2.5 is considered harmful to the respiratory system. However, little has been shown about the long-term association between ambient PM2.5 and asthma. METHODS: A survey from 2007 to 2010 was conducted among adults over 50 years of age in six low- and middle- income countries (including China, India, Ghana, Mexico, Russia, and South Africa), which belonged to one part of a prospective cohort study - the Study on global AGEing and adult health. The yearly mean PM2.5 concentrations of the residential communities of participants were estimated from remote sensing data. A mixed effects model was applied to investigate the association between ambient PM2.5 and asthma. RESULTS: A total of 4553 asthma patients were identified among the 29,249 participants in this study, producing a prevalence of 15.57%. For each 10 µg/m3 increase in PM2.5, the adjusted prevalence ratio of asthma was 1.05 (95% Confidence Interval: 1.01, 1.08) after controlling for the effects of sex, age, BMI, education attainment, smoking status, alcohol consumption, and occupational exposure. Further analyses showed that males and smokers might be particularly vulnerable populations. Additionally, it was estimated that about 5.12% of the asthma cases in the study population (95% Confidence Interval: 1.44%, 9.23%) could be attributed to long-term PM2.5 exposure. CONCLUSION: Long-term exposure to PM2.5 might be an important risk factor of asthma. Effective air pollution reduction measures should be taken to reduce PM2.5 concentrations in order to reduce the associated asthma cases and disease burden.