Aquatic Vegetables Research Articles

The King's initiatives using water hyacinth to remove heavy metals and plant nutrients from wastewater through Bueng Makkasan in Bangkok, Thailand

H.M. the King of Thailand proposed Bueng Makkasan, the repair factory belonging to the Royal Railway of Thailand (RTT), as a wastewater-collection pond of Bangkok City. It covers about 40 acres, with 5-m depth. The RRT wastewater pond functions at a repair factory and is the collection site of the direct-polluted waste of homeless people living around the pond rim and also for temporary reservoir of two influent canals. The water hyacinth aquatic plants were grown well and covered almost the entire surface area of the pond. An experimental design was laid by making a floating bamboo frame 5 m × 10 m in size and spreading systematical distribution through all parts of the pond with the coverage area 30 percent of pond surface. Data collection and analysis were conducted on plant nutrients, heavy metals and toxic chemicals in wastewater (influent, storage, and effluent) sediment, leaves and roots of water hyacinth (in fresh and compost). Also, the water hyacinth growth rate in various periods of time in relation to chemical concentration in wastewater were determined from the beginning through harvesting time. The results found that water hyacinth would be the high-absorbing plants to extract the heavy metals (such as Mn, Cd, Fe, Zn, Cu, and Pb) and plant nutrients (such as N, P, K, Ca, Mg). The floating aquatic vegetables contaminated via high concentration of heavy metals were not eaten under the regulations of Ministry of Public Health. Consequently, the compost that was made by water hyacinth showed a high concentration of heavy metals. An application of such compost would only be for flowering-plants growth, with no possibility of application to edible vegetables. The study also indicated that water hyacinth on the wastewater treatment pond would be maximized at 20 percent cover. Sunshine-open space needed the intensity of visible light for phytoplankton and other algae species to support the photosynthesis in order to produce enough oxygen for the power-digesting aerobes to degrade the organic waste in wastewaters.

Study on nutraceutical properties of different cultivars Ipomoea aquatica Forsskal (‘Chunbai’ and ‘Liulv’) in an eutrophic water body

Ipomoea aquatica Forsskal is a fast-growing aquatic economic plant and has been applied widely to purify eutrophic water, but little is known about the edible safety of it for humans or animals. The main purpose of our research was to assess the metal (copper, zinc, lead, cadmium and chromium) concentration and nutritional quality in the edible part of I. aquatica Forsskal (‘Chunbai’ and ‘Liulv’) growing in eutrophic water. The results showed that all levels of these metals were within the acceptable levels in our present studies, and the metal accumulating potential varied mainly depending upon levels of metal contamination in the water body in which they were growing. In the present investigation, nitrate content (NO 3–N) had no significant differences between ‘Chunbai’ and ‘Liulv’, but had significant differences ( p < 0.001) between eutrophic water and Hoagland nutrient solution. Soluble protein, soluble sugar, and vitamin C content were affected greatly by variety and solution (treatments). The soluble protein and vitamin C content in ‘Liulv’ were one time higher but the soluble sugar content was one time lower than that in ‘Chunbai.’ The soluble protein and soluble sugar of plants cultivated in nutrient solutions were one time lower than that in eutrophic water. In addition, the vitamin C content of plants grown in Hoagland nutrient solution was approximately two times higher than that in eutrophic water. The possible utilization of these aquatic vegetables to meet the demands of food and health perspectives for consumers is discussed.

Hepatic fascioliasis at a London hospital — the importance of recognising typical radiological features to avoid a delay in diagnosis

Hepatic fascioliasis is a zoonosis caused by the trematode Fasciola hepatica, which can cause hepatobiliary disease in humans via the ingestion of contaminated water or aquatic vegetables. Reported cases of human infection with F. hepatica arise in regions where cattle are raised, with particular abundance in South America and the Middle East. The typical radiological appearances associated with fascioliasis are well reported and are likely to be more easily recognisable by radiologists in these areas of high prevalence. However, in Western countries where the disease is seldom found, there may be a delay in diagnosis and treatment owing to unfamiliarity with the radiological appearances, in addition to the non-specific clinical features on presentation. Here we describe a case of a 22-year-old Bangladeshi woman whose only clinical feature was right upper quadrant pain. Abnormal imaging of her abdomen on admission began a process of investigations to seek the correct diagnosis.

In vitro antioxidative property of polyphenols present in two common aquatic leafy vegetables

Enydra fluctuans Lour. (Hinche or helencha) and Ipomea aquatica Forssk. (Kalmlsak) are traditionally consumed as leafy vegetables by the Indians. But little is known about its potential as sources of antioxidants. The 80% methanol extraction of these two vegetables showed the polyphenol content of 30.7 and 18.42 mg per g of dry matter. Both the extracts have shown reducing activity, DPPH radical scavenging activity and prolonged ABTS °+ radical scavenging activity. The result of the study indicates that the above vegetables are rich in active polyphenolic antioxidants, which are very much important from nutritional point of view.

High fascioliasis infection in children linked to a man-made irrigation zone in Peru.

We detected 10 protozoan and nine helminth species in surveys of 338 5-15 year-old Quechua schoolchildren in three communities of the Asillo zone of the Puno region, located at a very high altitude of 3910 m in the Peruvian Altiplano. The area proved to be hyperendemic for human fascioliasis with a 24.3% overall mean prevalence of Fasciola hepatica, local prevalences ranging between 18.8 and 31.3%, and infection intensities of up to 2496 eggs per gram of faeces (epg), with 196-350 epg (mean: 279 epg) and 96-152 epg (123 epg) as arithmetic and geometric means, respectively. Prevalences did not significantly vary between schools and in relation to sex. No statistical differences were found in intensities between schools, nor according to sex or age groups between and within schools, although the highest overall egg counts were detected in girls and in the youngest age group. Asillo zone is a man-made irrigation area built only recently to which both liver fluke and lymnaeid snails have quickly adapted. The region appears to be isolated from the Northern Bolivian Altiplano natural endemic area. Such man-made water resources in high altitude areas of Andean countries pose a high fascioliasis risk. Significant positive association of F. hepatica with protozooses following a one host life cycle, such as Giardia intestinalis, suggests that human infection mainly occurs through drinking water. This is supported by additional evidence such as the absence of typical aquatic vegetation in the drainage channels inhabited by lymnaeid snails, the absence of aquatic vegetables in the traditional nutrition habits of the Quechua inhabitants, and the lack of potable water systems inside dwellings, which requires inhabitants to obtain water from irrigation canals and drainage channels.

Micronutrient composition and nutritional importance of gathered vegetables in Vietnam.

This article presents the nutrient composition and nutritional contribution of naturally occurring vegetables (NOV) in four villages in Vietnam. The frequency of consumption and quantities eaten were evaluated within the overall diet of 101 and 110 women in the Mekong Delta (flood period and rainy season, respectively) and of 103 women in the Central Highlands (rainy season). The concentrations of Ca, Fe and Zn were analysed in 28 species, and presence of tannins and phytic acid in 19 species. Provitamin carotenoids were determined in 11 species. Over 90% of the women consumed NOV, and they contributed 43, 72 and 75% (Central Highlands, Mekong rainy and Mekong flood period, respectively) of the total quantities of vegetables eaten. Aquatic species such as lpomoea aquatica and Limnocharis flava, and terrestrial vegetables such as Schismattoglottis calyptrata, were among the most commonly consumed vegetables. They were eaten in mean daily quantities exceeding 50 g and had high concentrations of Ca, Fe and beta-carotene. Other major aquatic vegetables included the stems of Eleocharis sp., Nelumbo nucifera and Nymphea lotus, all of which were used as salad vegetables and had relatively low nutrient density. The problems of assessing the current role of NOV due to lack of data on intakes in the context of the overall diets, as well as data on their composition, are addressed.

The contribution of wild vegetables to micronutrient intakes among women: An example from the Mekong delta, Vietnam

No previous dietary intake study in Vietnam has focused on contemporary use of wild vegetables (Rau dai). In this study the contribution of such gathered vegetables to micronutrient intake of women was investigated in two villages in the Mekong Delta, Vietnam. Dietary assessments (24‐h recall and repeated 7‐day FFQ) were conducted on 110 and 101 women, respectively, in the rainy season as well as the flood period. Twenty aquatic and terrestrial wild vegetables were recorded in the dietary assessments. Popular wild species were among the most frequently used vegetables, used alternatively with home‐cultivated or commercial vegetables. Wild plants contributed 81% and 63%, respectively, of the daily intake of vegetables during the flood period and rainy season. They made important contributions to the intake of carotene, vitamin C, calcium and iron. We conclude that there is a need to pay specific attention to the role of wild vegetables especially in the diets of the rural poor.

Micronutrient composition and nutritional importance of gathered vegetables in Vietnam

This article presents the nutrient composition and nutritional contribution of naturally occurring vegetables (NOV) in four villages in Vietnam. The frequency of consumption and quantities eaten were evaluated within the overall diet of 101 and 110 women in the Mekong Delta (flood period and rainy season, respectively) and of 103 women in the Central Highlands (rainy season). The concentrations of Ca, Fe and Zn were analysed in 28 species, and presence of tannins and phytic acid in 19 species. Provitamin carotenoids were determined in 11 species. Over 90% of the women consumed NOV, and they contributed 43, 72 and 75% (Central Highlands, Mekong rainy and Mekong flood period, respectively) of the total quantities of vegetables eaten. Aquatic species such as lpomoea aquatica and Limnocharis flava, and terrestrial vegetables such as Schismattoglottis calyptrata, were among the most commonly consumed vegetables. They were eaten in mean daily quantities exceeding 50 g and had high concentrations of Ca, Fe and β -carotene. Other major aquatic vegetables included the stems of Eleocharis sp., Nelumbo nucifera and Nymphea lotus, all of which were used as salad vegetables and had relatively low nutrient density. The problems of assessing the current role of NOV due to lack of data on intakes in the context of the overall diets, as well as data on their composition, are addressed.

MR findings in human fascioliasis

Fasciola hepatica is a trematode of herbivorous mammals, and man is infected by accidental ingestion of contaminated raw aquatic vegetables or water. There have been many reports on computed tomographic and cholangiographic features of human fascioliasis. However, findings of magnetic resonance (MR) imaging have not been reported. Hepatic fascioliasis produces three types of lesions in MR images arranged in tract-like fashion. The outermost area presents as an iso-signal area in T1WI, with slightly higher signal intensity in T2WI and diffuse enhancement after i.v. contrast. The second type presents as a well defined low signal area in T1WI, not enhanced, and also shows low signal intensity in T2WI. The third type has low signal intensity in T1WI, is not enhanced, and has high signal intensity in T2WI which is similar to fluid-containing inflammatory lesions such as pyogenic abscess. These findings suggest various changes associated with traumatic hepatitis caused by the migration of the worm in the liver. This diverse signal intensity can be a suggestive finding of fascioliasis.

Radiological findings of human fascioliasis.

Fasciola hepatica is a trematode of herbivorous mammals. Humans are accidentally infected by the ingestion of water or raw aquatic vegetables contaminated with the metacercaria. Radiological findings of six patients with fascioliasis (five hepatic fascioliasis, one biliary fascioliasis) were analyzed. The diagnosis was based on serological testing and/or histopathologic findings of eosinophilic abscess in five patients and identification of the adult worm in one patient. The characteristic radiological features of hepatic fascioliasis were (1) cluster of microabscesses arranged in tract-like fashion (burrow tract), (2) subcapsular location of the hepatic lesions, and (3) very slow evolution of the lesion on follow-up examinations. In biliary fascioliasis, there were multiple conglomerated filling defects in the common bile duct. The authors believe that the demonstration of these features, together with peripheral eosinophilia or eosinophilic aspirate from the hepatic lesion, is very helpful in making the correct diagnosis.

Vegetable crops growing in China

China is one of the oldest centres for vegetable crops. Some of them can still be found in the wild or semi-wild state, but some have already spread to other countries to become world-wide crops. There are many species currently growing that are peculiar to China, including aquatic vegetables, bamboo sprouts and several kinds of beans, gourds, tubers and greens. Quite a number of Brassica varieties are widely grown. Some are considered to have originated in north China ( B. pekinensis), and some in central and south China ( B. chinensis and B. juncea), and then spread out to Japan and south-eastern Asia. Schemes for the development of different varieties are suggested.