Venezuelan Amazon Research Articles

Physicochemical, Functional, and Macromolecular Properties of Waxy Yam Starches Discovered from “Mapuey” (Dioscorea trifida) Genotypes in the Venezuelan Amazon

"Mapuey" tubers in Venezuela are staple food for indigenous peoples from the Caribbean coast and Amazon regions. Noticeable differences between genotypes of yam starches were observed. Granules were large, triangular, or shell-shaped with monomodal particle size distribution between 24.5 and 35.5 μm. Differential scanning calorimetry (DSC) analyses revealed onset gelatinization temperatures from 69.1 to 73.4 °C with high gelatinization enthalpy changes from 22.4 to 25.3 J g(-1). All X-ray diffractograms of starches exhibit B-type crystallinity. Crystallinity degrees varied from 24% to 40%. The highest crystallinity was found for the genotype having the highest amylose content. Iodo-colorimetric, amperometric, and DSC amylose determinations varied from 1.4 to 8.7%, 2.2 to 5.9%, and 1.4 to 3.5% for Amazonian genotypes, in comparison with commercial Mapuey starches: 12.0, 9.5, and 8.7%, respectively. Solubility and swelling power at 90 °C varied from 2.1 to 4.4% and 20.5 to 37.0%, respectively. Gel clarity fluctuated from 22.4 to 79.2%, and high rapid visco analyzer (RVA) viscosity was developed at 5% starch suspension (between 1430 and 2250 cP). Amylopectin weight average molar mass M(w), radius of gyration R(G), hydrodynamic coefficient ν(G), and apparent molecular density d(Gapp) were determined using high-performance size exclusion chromatography (HPSEC) and asymmetrical flow field flow fractionation (A4F) techniques coupled with multiangle laser light scattering (MALLS) on the Dioscorea trifida genotypes exhibiting the lowest and highest amylose contents. Amylopectins showed very similar molecular conformations. M(w) values were 1.15 × 10(8) and 9.06 × 10(7) g mol(-1) using HPSEC and A4F, respectively, thus, 3-5 times lower than those reported with the same techniques for other yam species, and very close to those of potato and cassava amylopectins. This discovery of a new natural amylose-free starch in the neglected yam "Mapuey" could present some potential for the food industry.

A rapid malaria appraisal in the Venezuelan Amazon

BackgroundWhile the federal state of Amazonas bears the highest risk for malaria in Venezuela (2007: 68.4 cases/1000 inhabitants), little comprehensive information about the malaria situation is available from this area. The purpose of this rapid malaria appraisal (RMA) was to provide baseline data about malaria and malaria control in Amazonas.MethodsThe RMA methodology corresponds to a rapid health impact assessment (HIA) as described in the 1999 Gothenburg consensus. In conjunction with the actors of the malaria surveillance system, all useful data and information, which were accessible within a limited time-frame of five visits to Amazonas, were collected, analysed and interpreted.ResultsMortality from malaria is low (< 1 in 105) and slide positivity rates have stayed at the same level for the last two decades (15% ± 6% (SD)). Active case detection accounts for ca. 40% of slides taken. The coverage of the censured population with malaria notification points (NPs) has been achieved in recent years. The main parasite is Plasmodium vivax (84% of cases). The proportion of Plasmodium falciparum is on the decline, possibly driven by the introduction of cost-free artemisinin-based combination therapy (ACT) (1988: 33.4%; 2007: 15.4%). Monitoring and documentation is complete, systematic and consistent, but poorly digitalized. Malaria transmission displayed a visible lag behind rainfall in the capital municipality of Atures, but not in the other municipalities. In comparison to reference microscopy, quality of field microscopy and rapid diagnostic tests (RDTs) is suboptimal (kappa < 0.75). Hot spots of malaria risk were seen in some indigenous ethnic groups. Conflicting strategies in respect of training of community health workers (CHW) and the introduction of new diagnostic tools (RDTs) were observed.ConclusionMalaria control is possible, even in tropical rain forest areas, if the health system is working adequately. Interventions have to be carefully designed and the features of the particular local Latin American context considered.

The Celestial Umbilical Cord

This article focuses on the multiple uses and meanings of wild palm species as sources of musical wind instruments and edible fruits in sacred ceremonies and rituals of the Wakuénai (or Curripaco) living in the Venezuelan Amazon. In myth, the emergence of a macanilla (púpa) tree from the ashes of the primordial human being (Kuwái) became the source of sacred flutes and trumpets, and the sounds made by these wind instruments opened up the world for a second time. In ritual and ceremonial performances, the different instruments have animal namesakes and are also said to be different parts of the body of Kuwái. This article explores these intimate relations among wild palm species, adult male bodies, sacred wind instruments, and the primordial human being of myth. The article also draws on verbal and nonverbal imagery performed in sacred singing and chanting (malikái) in which wild palm species are associated with the celestial umbilical cord that nourishes humanity with the life-giving and world-creating powers of Kuwái and other powerful mythic beings.

Agricultural Systems Located in the Forest-Savanna Ecotone of the Venezuelan Amazonian. Are Organic Agroforestry Farms Sustainable?

The savannas located in the forest-savanna ecotone in the Venezuelan Amazon have unfertile sandy ultisols and entisols which show a very low crop production unless they are supplemented with large amounts of fertiliser. In spite of this restriction, local farmers have established long-term production systems by using low input doses of organic manure. The use of organic waste in unfertile ultisols and entisols typical of savannas have resulted in increases in organic matter content and biological activities in soils with respect to inorganic fertilised or non-fertilised natural savanna, which, in turn, may be related to increases in crop productivity. These results could be a successful and reliable soil management technique for rehabilitation of the South American savannas.

The Importance of Traditional Ecological Knowledge for Palm-weevil Cultivation in the Venezuelan Amazon

Entomophagy is widespread among indigenous people, promoting the gathering of traditional ecological knowledge of insect life histories and plant-insect interactions. In the Amazon, the cultivation of palm weevil larvae (Rhynchophorus palmarum and Rhinostomus barbirostris) for food provides an important supplement to the diets of many indigenous people. This study conducted with the Jotï people from Venezuelan Amazonia examined their traditional ecological knowledge (TEK) of palm (Oenocarpus bacaba) and weevil interactions and how they have applied their TEK to optimize returns on palm weevil cultivation. They manipulate palms to induce changes in the resource-partitioning and competition that occurs naturally between weevil species, thereby increasing harvests of their preferred species of weevil. We found that the Jotï's traditional ecological knowledge was congruent with scientific findings of weevil natural history and palm and weevil interactions. This analysis identifies potential research directions that may provide solutions to agricultural problems such as palm weevil infestations in palm plantations. We conclude that understanding and preserving traditional ecological knowledge and practices is important for organisms such as palm weevils that rarely have been studied in their natural forest settings.

Piaroa Manioc Varietals: Hyperdiversity or Social Currency?

The maintenance of exceptionally high numbers of folk varieties by the Piaroa people of the Venezuelan Amazon is considered. We cataloged 113 manioc folk varieties, their nomenclature, use and relevant characters, revealing significant insights into the role of manioc in Piaroa social life. Through a qualitative investigation of the cultivation, processing and symbolic significance of manioc (Manihot esculenta) in two Piaroa regions over a period of 18 years, we have found that such agrobiodiversity can only be fully explained by a combination of multiple factors, including pragmatic and ecological considerations, the subtle and complex diversity of Piaroa manioc preparations and a variety of sociocultural factors, such as manioc’s role as a mediator of social relationships and as a marker of cultural and social heritage.

Antidiabetic and antiradical activities of plants from Venezuelan Amazon

The aqueous and ethanol extracts derived from twelve plant species collected in the Venezuelan Amazon have been tested for antioxidant activity using a DPPH radical and inhibitory effect on the hydrolysis of glucose-6-phosphate in intact and disrupted microsomes. Without exception, all the extracts inhibited, to a greater or lesser degree, microsomal G-6-Pase enzymatic activity, resulting in greater inhibition on intact microsomes than on disrupted ones. Marked effects were observed for aqueous and ethanol extracts of: Tontelea ovalifolia, Gustavia pulchra, Phthirusa verruculosa, Phthirusa castillana, Psittacanthus acimarius, Tetrapterys styloptyera and Vismia japurensis. Ethanol extracts were more effective DPPH radical scavengers than the corresponding aqueous extracts in all the cases. The ethanol extract of Endlicheria anomala and the aqueous extract of Phthirusa verruculosa, showed the best IC50 with 100 and 250.0 ppm, respectively. The Kobs calculated for the alcoholic extracts were lower than those of the aqueous extracts for the same species, except Psittacanthus acimarius. These results could be related to different concentrations, or more likely different compositions of active principles in both extracts.

Hyperreactive malarial splenomegaly is associated with low levels of antibodies against red blood cell and Plasmodium falciparum derived glycolipids in Yanomami Amerindians from Venezuela

The immunological basis of the aberrant immune response in hyperreactive malarial splenomegaly (HMS) is poorly understood, but believed to be associated with polyclonal B cell activation by an unidentified malaria mitogen, leading to unregulated immunoglobulin and autoantibody production. HMS has been previously reported in Yanomami communities in the Upper Orinoco region of the Venezuelan Amazon. To investigate a possible association between antibody responses against Plasmodium falciparum and uninfected red blood cell (URBC) glycolipids and splenomegaly, a direct comparison of the parasite versus host anti-glycolipid antibody responses was made in an isolated community of this area. The anti- P. falciparum glycolipid (Pfglp) response was IgG3 dominated, whereas the uninfected red blood cell glycolipid (URBCglp) response showed a predominance of IgG1. The levels of IgG1 against Pfglp, and of IgG4 and IgM against URBCglp were significantly higher in women, while the anti-Pfglp or URBCglp IgM levels were inversely correlated with the degree of splenomegaly. Overall, these results suggest differential regulation of anti-parasite and autoreactive responses and that these responses may be linked to the development and evolution of HMS in this population exposed to endemic malaria. The high mortality rates associated with HMS point out that its early diagnosis together with the implementation of malaria control measures in these isolated Amerindian communities are a priority.

Malaria diagnosis under field conditions in the Venezuelan Amazon

To improve practical, accurate diagnosis of malaria in the Amazon rainforest of Venezuela, two rapid diagnostic tests (RDT) (OptiMAL-IT) and FalciVax) and a laboratory light microscope, used in the field with a battery-operated head lamp as an external light source, were evaluated against the standard laboratory microscope procedure for malaria detection. One hundred and thirty-six Yanomami patients were studied for the presence of malaria parasites. Thirty-three patients (24%) were positive for malaria (Plasmodium falciparum, P. vivax, P. malariae). Twenty-one (64%) of the positive patients had <100 parasites/microl. Both RDTs showed poor sensitivity (24.2% for OptiMAL-IT) and 36.4% for FalciVax) but good specificity (99% both for OptiMAL-IT) and FalciVax). Field and laboratory microscopy showed sensitivities of 94% and 91%, respectively. The kappa coefficient was 0.90, indicating a high agreement between field and laboratory microscopy. We conclude that (i) adequate slide reading cannot be substituted by either of the two RDTs in the Venezuelan Amazon and (ii) the use of a light source such as that described above makes slide reading more feasible than hitherto in remote areas without electricity.

Music in Latin America and the Caribbean: An Encyclopedic History: Volume 1: Performing Beliefs: Indigenous Cultures of South America, Central America, and Mexico (review)

Reviewed by: Music in Latin America and the Caribbean: An Encyclopedic History: Volume 1: Performing Beliefs: Indigenous Cultures of South America, Central America, and Mexico Mark E. Perry Music in Latin America and the Caribbean: An Encyclopedic History: Volume 1: Performing Beliefs: Indigenous Cultures of South America, Central America, and Mexico. Edited by Malena Kuss. Austin, TX: University of Texas Press, 2004. [xxx, 416 p. ISBN 0-292-70298-1. $60.] Index, bibliography, illustrations, music examples, compact discs. Malena Kuss, musicologist and professor emeritus of the University of North Texas, has edited an informative volume that explores the role of music and worldviews of the indigenous peoples of Latin America. The editor notes that the initial volume of the series "focuses on the inextricable relationships between worldviews and musical behavior in current and relatively recent practices of indigenous groups" (p. xix). The work marks the first installment of a four-volume study of the music of Mexico, Central America, South America, and the Caribbean, the latter being excluded from this volume. Symptomatic of an edited work with multiple contributors, the book contains chapters that vary significantly in scope, length, and method. While the central theme of the volume is not entirely cohesive, the diversity of the authors' approaches and backgrounds guarantees no privileging of a single perspective, and skillfully captures the complexities of the subject. Kuss argues that by "[adhering] to the principle that these [musical traditions] have to be studied at the local level," this work "can contribute in some measure to eradication of essentialisms and to critical reassessments of the infinite ways in which cultural representations still relies on criteria and conceptual frameworks developed within the Eurocentric sphere of influence, including some models of cultural criticism stemming from vastly different historical experiences" (p. xix). Following this approach, Carol E. Robertson composed numerous chapters of the book, also contributing a brief epilogue. In her first essay, she provides an overview of the intricate and diverse history of Latin America that complements the editor's prologue. Robertson goes on to discuss the nguillipún, a fertility ritual practiced in southern Chile and Argentina by the Tehuelche, Pehuenche, Günuna-Kena, Huarpe, Ranquel, Puelche, and Mapuche to heighten the fertility of livestock and crops. In later chapters, Robertson surveys broad themes in a more generalized nature, [End Page 872] including myth, cosmology, and the healing powers of music. Jonathan D. Hill examines the Kwépani and Pudáli, two separate ceremonial activities of the Wakuénai, indigenous people of the Venezuelan Amazon. In the Kwépani, initiated men assemble wild fruits, lash each other with ritual whips (essentially becoming living drums), and play sacred flutes and trumpets. In this male-dominated ceremony, social continuity and regeneration occur as exchanges transpire between ancestors and their descendents. The Pudáli is a ceremony that involves both sexes, with trade occurring between guests and a host village. At the beginning of the ceremony, an evident separation between the two groups exists; however, as the Pudáli progresses and exchanges of smoked meat for vegetable products take place, social boundaries between the two groups slowly dissipate. The author connects the vertical dimension of the Kwépani and horizontal nature of the Pudáli within the broader cosmology of the Wakuénai. Max Peter Baumann similarly discusses the role of panpipe ensembles and their relation to the worldview of the indigenous inhabitants of the Bolivian Andes. In their conceptualization of music making, the rural population conflates music, dance, song, and ritual. The annual cycle of religious rituals—a combination of the agricultural cycle, Inca calendar, and Gregorian calendar—provides the context of their contemporary musical behavior. Panpipe ensembles of the Bolivian Andes exhibit symbolic dualism, a primary feature of the Andean worldview. The interlocking technique employed to play panpipes, which requires pairs of panpipes ira/arka, serves as a manifestation of this duality. Following his analysis, Baumann concludes his insightful essay with a list of relevant hypotheses concerning pre-contact musical practices. Dale A. Olsen also provides a lengthy and detailed cross-cultural and geographical examination of Central American and South American indigenous wind instruments. His analysis takes into account the function and construction of the...

Globalización, desigualdad y transmisión de las enfermedades tropicales en el Amazonas venezolano

Economic globalization appears to be causing greater inequalities and increased vulnerability to tropical diseases around the world. The Venezuelan Amazon population, especially the rural indigenous population, displays among the worst health indicators in the Americas. High infant mortality rates in remote indigenous populations indicate that such communities have been affected by the globalization of disease, rather than favored by globalization of health. Globalization has also influenced public policies in the country, affecting the efficiency of control programs targeting tropical diseases. A new global pact for the sustainable development of the planet is needed, supported by the globalization of human values and rights. In Venezuela, new policies for the indigenous health sector, more resources, and greater autonomy could help reduce the inequities described here in the Venezuelan Amazon.

Endemic Pemphigus Foliaceus in Venezuela: Report of Two Children

Two native Yanomami children from the Venezuelan Amazonia with erythroderma were hospitalized on our service. Clinical, histologic, and immunofluorescence studies diagnosed endemic pemphigus foliaceous. Human leukocyte antigen class II showed DRB1*04 subtype *0411, which has not been previously associated with this disease. However, it shares a common epitope with all the human leukocyte antigen DRB1 alleles that have been involved in this disease among Brazilian populations. Although this condition is endemic in Brazil, our patients are the first two reported in Venezuela.

High sequence diversity and evidence of balancing selection in the Pvmsp3α gene of Plasmodium vivax in the Venezuelan Amazon

The genetic diversity of a defined Plasmodium vivax population from the Venezuelan Amazon was evaluated by direct sequencing of the gene encoding the P. vivax merozoite surface protein-3α, Pvmsp3α. Three allele sizes (1.9, 1.4 and 1.1 kb) were amplified from 58 isolates with frequencies of 59.3%, 21.9% and 18.8%, respectively. 27 Pvmsp3α nucleotide sequences were determined, with nine distinct haplotypes observed. The genetic diversity ( h) at this single locus was 0.774. The P. vivax population in this region exhibits significant diversity in contrast to the genetically restricted diversity of the sympatric P. falciparum population. Despite sharing vector and human hosts, different control strategies may be required for these two species in this region. Substitution patterns in the conserved C-terminus of Pvmsp3α showed a significant departure from neutrality, suggesting these polymorphisms are being maintained by frequency-dependent selection as the result of an effective immune response from the host. Our findings support the use of Pvmsp3α genotyping as a tool for monitoring interventions aimed at control of P. vivax.

Korfiomyces gelatinosum gen. et sp. nov., a New and Enigmatic Gelatinous Discomycete from the Venezuelan Amazon with Lecanoralean Affinities

Korfiomyces gelatinosum gen. et sp. nov. is described from resinous wood of an unidentified tree in the Venezuelan Amazon, part of the Guayana region; it is saprobic and not lichenized. The ascomata are apothecioid, arise on a brownish subiculum, are gelatinous and initially have a raised exciple. The asci are lecanoralean with a thin outer amyloid layer and occasionally a minute internal apical amyloid ring. The paraphyses are simple and capitate, and the as-cospores brownish and 1-septate. The possible affinities of the new genus are discussed; no family to accommodate it satisfactorily was found, and for the time being it is recommended that it be treated as Lecanoromycetes incertae sedis.

Korfiomyces gelatinosum gen. et sp. nov., a new and enigmatic gelatinous discomycete from the Venezuelan Amazon with lecanoralean affinities

Korfiomyces gelatinosum gen. et sp. nov. is described from resinous wood of an unidentified tree in the Venezuelan Amazon, part of the Guayana region; it is saprobic and not lichenized. The ascomata are apothecioid, arise on a brownish subiculum, are gelatinous and initially have a raised exciple. The asci are lecanoralean with a thin outer amyloid layer and occasionally a minute internal apical amyloid ring. The paraphyses are simple and capitate, and the as-cospores brownish and 1-septate. The possible affinities of the new genus are discussed; no family to accommodate it satisfactorily was found, and for the time being it is recommended that it be treated as Lecanoromycetes incertae sedis.

Cross-sectional study defines difference in malaria morbidity in two Yanomami communities on Amazonian boundary between Brazil and Venezuela.

It is well established that immunity to malaria is short-lived and is maintained by the continuous contact with the parasite. We now show that the stable transmission of malaria in Yanomami Amerindian communities maintains a degree of immunity in the exposed population capable to reduce prevalence and morbidity of malaria. We examined 508 Yanomami Amerindians living along Orinoco (407) and Mucajaí (101) rivers, on the Venezuelan and Brazilian Amazon region, respectively. At Orinoco villages, malaria was hyperendemic and presented stable transmission, while at Mucajaí villages it was mesoendemic and showed unstable transmission. The frequency of Plasmodium vivax and P. falciparum was roughly comparable in Venezuelan and Brazilian communities. Malaria presented different profiles at Orinoco and Mucajaí villages. In the former communities, malaria showed a lower prevalence (16% x 40.6%), particularly among those over 10 years old (5.2% x 34.8%), a higher frequency of asymptomatic cases (38.5% x 4.9%), and a lower frequency of cases of severe malaria (9.2% x 36.5%). Orinoco villagers also showed a higher reactivity of the immune system, measured by the frequency of splenomegaly (72.4% x 29.7%) and by the splenic index (71.4% over level 1 x 28.6), and higher prevalence (91.1% x 72.1%) and mean titer (1243 x 62) of antiplasmodial IgG antibodies, as well as a higher prevalence (77.4% x 24.7%) and mean titer (120 x 35) of antiplasmodial IgM antibodies. Our findings show that in isolated Yanomami communities the stability of malaria transmission, and the consequent continuous activation of the immune system of the exposed population, leads to the reduction of malaria prevalence and morbidity.

Knowledge and Use of Fungi by a Mycophilic Society of the Venezuelan Amazon

This paper reports on the knowledge and useful applications of various fungi by the Hoti, a recently contacted Native American society inhabiting the Sierra Maigualida region of the Venezuelan Amazon. At least 31 folk taxa of fungi are esteemed as sources of nutrition, powerful media for hunting magic, protective charms against black magic, human medicinal agents, or body adornments. Even though the results presented here probably do not exhaust the total number of species known and used by them, they nevertheless suggest that the Hoti constitute one of the rare mycophilic societies in the Venezuelan Amazon. Further research is needed in order to obtain a more complete picture of the complexity of humanfungi relationships in this society.

A New Norkaurane‐γ‐Lactone from Parinari sprucei

AbstractFor Abstract see ChemInform Abstract in Full Text.

Preliminary assessment of medicinal plants used as antimalarials in the southeastern Venezuelan Amazon.

Eighteen species of medicinal plants used in the treatment of malaria in Bolívar State, Venezuela were recorded and they belonged to Compositae, Meliaceae, Anacardiaceae, Bixaceae, Boraginaceae, Caricaceae, Cucurbitaceae, Euphorbiaceae, Leguminosae, Myrtaceae, Phytolaccaceae, Plantaginaceae, Scrophulariaceae, Solanaceae and Verbenaceae families. Antimalarial plant activities have been linked to a range of compounds including anthroquinones, berberine, flavonoids, limonoids, naphthquinones, sesquiterpenes, quassinoids, indol and quinoline alkaloids.

A new norkaurane-gamma-lactone from Parinari sprucei.

The title tetracyclic diterpenoid, 10,13,16,17-tetrahydroxy-9-methyl-15-oxo-20-norkaurane-18,10-carbolactone hemihydrate, C(20)H(28)O(6).0.5H(2)O, is a plant metabolite from Parinari sprucei, part of the Venezuelan Amazon flora. The asymmetric unit consists of two nearly identical molecules of the diterpenoid and one molecule of water. Some of the geometric parameters reflect steric strain in the molecule. The extended structure is characterized by hydrogen bonds and weaker hydrogen-mediated interactions, which involve all of the hydroxy groups and propagate in sheets that coincide with the (002) family of planes. The water molecule acts as a double hydrogen-bond donor and single acceptor and thus plays a critical role in the pattern of intermolecular interactions.