The genus Ficus (Moraceae) used in diet: Its plant diversity, distribution, traditional uses and ethnopharmacological importance

ETHNOPHARMACOLOGICAL RELEVANCE

A new field of enthnopharmacology has opened, where pharmacological studies draw their attention from the conventional only-medicine approach towards the dietary dimension. The uses of Ficus species in the human diet have been extensively documented by ethnobotanical field surveyors. Overlap commonly exist between the dietary and medicinal selection of Ficus species but not for choices of the plant parts and development stages, which leave a large space for ethnopharmacological study.

AIMS OF THE STUDY

1) To review published works on the dietary uses of Ficus species and their food-medicine overlap based on traditional uses, and 2) to spark interest in ethnopharmacological studies on the dietary uses of Ficus species.

MATERIALS AND METHODS

Data was collected and analyzed from many sources, including published and unpublished ethnobotanical field surveys, taxonomic and distribution information, international journals, books, thesis, floras, reports and professional databases. The possible biases arising from data sources are assessed to make sure that the dataset are global representative.

RESULTS

A total of 132 Ficus species are reported for dietary uses, including one subspecies and four varieties. Those species are found across all of the six subgenera of the genus Ficus. For distribution, 98 species from the Indo-Australasian region, 27 species from the African tropics (with one species, F. palmata, from both the two regions) and 8 from the Neotropics. The parts most commonly used are the figs (i.e. syconium or fruits) (110 species) and leaves (67 species), in various growth stages. It is also found that the certain plant parts of 78 species are used both for dietary and medicinal purpose. Among which the figs are frequently cited in the treatment of diarrhea and oligogalactia, the leaves in the treatment of diarrhea, stomach complaintsas, antidote and diabetes, the latex in the treatment of intestinal worms and wounds, and the barks in the treatment of diarrhea.

CONCLUSIONS

We demonstrate that throughout its area of distribution, the genus Ficus is generally used as a dietary plant, although use of a individual species seems uncommon. Furthermore, we highlight the diet-medicine overlap of the uses of this genus, which should enable further understanding of the potential for broader health benefits, rather than limiting studies in this genus to its only-medicinal properties.

Foraging dispersion of Ryukyu flying-foxes and relationships with fig abundance in East-Asian subtropical island forests

BACKGROUND

Figs are widely distributed key resources to many tropical-subtropical animals, and flying-foxes are major consumers and seed dispersers of figs. Bat-fig interrelationships, however, may vary among species differing in fruiting traits, i.e., bat- versus bird-dispersed figs. We examined Ryukyu flying-fox foraging dispersion and the relationships with tree species composition and fig abundance in forests of Iriomote Island.

RESULTS

Bat foraging dispersion showed no spatial patterns with respect to different areas of the island, and was not explained by heterogeneity, density, or basal area (BA) of total trees, nor by relative density or BA of fruiting trees or total fruiting figs among sites. Instead, bat densities were positively dependent on the relative density of total figs, and particularly the relative BA of bat-dispersed figs Ficus septica and F. variegata. Both species were dominant figs in forests, fruiting asynchronously with long crop seasons, and were used as predominant foods. Bats foraged mostly solitarily and the mean density was in a hump-shaped relationship with crop sizes of the dominant bat-figs. These two species and Ficus benguetensis are larger-sized bat-figs, all contained more seeds, higher dry-pulp mass and water mass, but not necessarily water content. By approximate estimation, higher proportions of seeds of these bat-figs would have been removed from fruits through the bat consumption, than that of small-sized bird-figs like F. virgata, F. superba, and F. microcarpa.

CONCLUSIONS

The foraging dispersion of Ryukyu flying-foxes in forests depends on the availability of the most abundant bat-figs that serve as predominant foods. Intermediate levels of crop sizes of theses figs appear most fit with their solitary foraging. Our results suggest that as density and BA coverage of these dominant bat-figs are below a certain level, their effectiveness to attract bats may dwindle and so would their chance of dispersal by bats.

Consumption of fig fruits grown in Oman can improve memory, anxiety, and learning skills in a transgenic mice model of Alzheimer's disease

Alzheimer disease (AD) is one of the most common forms of dementia in the elderly. Several reports have suggested neurotoxic effects of amyloid beta protein (Aβ) and role of oxidative stress in AD. Figs are rich in fiber, copper, iron, manganese, magnesium, potassium, calcium, vitamin K, and are a good source of proanthocyanidins and quercetin which demonstrate potent antioxidant properties. We studied the effect of dietary supplementation with 4% figs grown in Oman on the memory, anxiety, and learning skills in APPsw/Tg2576 (Tg mice) mice model for AD. We assessed spatial memory and learning ability, psychomotor coordination, and anxiety-related behavior in Tg and wild-type mice at the age of 4 months and after 15 months using the Morris water maze test, rota-rod test, elevated plus maze test, and open-field test. Tg mice that were fed a control diet without figs showed significant memory deficits, increased anxiety-related behavior, and severe impairment in spatial, position discrimination learning ability, and motor coordination compared to the wild-type control mice on the same diet, and Tg mice fed on 4% fig diet supplementation for 15 months. Our results suggest that dietary supplementation of figs may be useful for the improvement of cognitive and behavioral deficits in AD.

Characterisation of volatiles in dried white varieties figs (Ficus carica L.)

The aromatic profile of volatiles in dried figs varieties Bružetka Bijela and Zimnica were characterised by headspace solid-phase (HS-SPME) procedure with gas chromatography-mass spectrometry analysis (GC-MS). The volatile compounds were distributed by distinct chemical classes, including alcohols, aldehydes, esters, terpenic compounds, and other compounds. The figs were dried in a pilot plant cabinet dryer. Prior to drying process, figs were pre-treated by sulphur dioxide, immersed in solution of citric acid and ascorbic acid, respectively. Several mathematical thin-layer drying models, available in the literature, were fitted to experimental data of figs, implementing non-linear regression analysis techniques. The results showed that pre-treatments of figs decrease significantly the drying time. The best thin-layer drying model in terms of fitting performance was Wang and Singh model. The major volatile compound in dried figs was benzaldehyde. After benzaldehyde, the most abundant aldehyde in dried figs was hexanal. The comparison among dried figs showed the highest abundance of aldehydes, in general, in non-treated (control) dried figs compared to pre-treated samples. Furthermore, ascorbic acid was the most efficient in preserving esters and alcohols in case of Bružetka Bijela, whereas in case of Zimnica, sulphur dioxide was in advance compared to ascorbic acid. Ethyl acetate was the most abundant ester found in dried figs. Among other compounds, 2-butanone,3-hydroxy was the most abundant identified volatiles. Linalool, as the only identified terpen, was in case of both dried fig varieties, preserved by immersion into ascorbic acid. The immersion into citric acid has not been so successful in volatiles conservation.