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PubMed1990

Antimalarial compounds containing an alpha,beta-unsaturated carbonyl moiety from Tanzanian medicinal plants.

Pure compounds were isolated from plant extracts with antimalarial activity. The extracts were obtained from the tubers of Cyperus rotundus L. (Cyperaceae), the rootbark of Zanthoxylum gilletii (De Wild) Waterm. (Rutaceae), and the rootbark of Margaritaria discoidea (Baill.) Webster (Euphorbiaceae). The most active compounds included (IC50 within brackets): alpha-cyperone (1) (5.5 micrograms/ml), N-isobutyldeca-2,4-dienamide (2) (5.4 micrograms/ml), and securinine (3) (5.4 micrograms/ml). A mixture of autoxidation products of beta-selinene was found to be the most active antimalarial substances obtained from C. rotundus (5.6 micrograms/ml.

Animals↗
PubMed2002

Using stable isotope analyses to identify allochthonous inputs to Lake Naivasha mediated via the hippopotamus gut.

The hippopotamus grazes nocturnally on land and resides in water during the day. Much of the ingested material must therefore be defecated directly into the aquatic system and can thus be considered an allochthonous resource available to aquatic consumers. The utility of stable isotope analyses of carbon and nitrogen to distinguish hippo faecal matter from other potential basal resources was tested at Lake Naivasha, Kenya. Hippopotami proved faithful to a short grass diet although supplementary grazing of aquatic macrophytes was observed. The typical isotopic ratios of C4 grasses ingested were not altered substantially by gut processes, and were clearly distinct from algal and aquatic macrophyte isotopic ratios. However, marginal plants such as Cyperus papyrus exhibit C4 ratios, and so the technique is suitable only for use in localities where 'contamination' from such sources is negligible.

Animals↗
PubMed2005

Population dynamics of weeds in no-tillage and conventional crop systems.

Population dynamics of weeds in successive maize and bean crops were evaluated in two soil management systems (conventional and no-tillage), for two maize applications (grain and silage), and in four consecutive growing seasons. Every year, conventional tillage consisted in plowing and harrowing before sowing. In no-tillage, chemical weed desiccation was made with the mixture glyphosate + 2.4-D. To control weeds, the mixture fluazifop-p-butil + fomesafen was applied on the bean crop in all the planting seasons, and the herbicides nicosulfuron + atrazine on maize after crop emergence (1998--1999, 1999--2000, 2001--2002) and atrazine + metolachlor before emergence (2000--2001). Purple nutsedge (Cyperus rotundus) was the most important species under conventional soil tillage; while in no-tillage the dicotyledonous weed species (Amaranthus deflexus, Bidens pilosa, Euphorbia heterophylla, Galinsoga parviflora Ipomoea grandifolia) were the most relevant. Regardless of the maize use, the C. rotundus population and tuber bank, with prevailingly dormant tubers, was considerably reduced in no-tillage compared with the conventional system.

Agriculture↗
PubMed2005

Effects of hand weeding strip and nitrogen fertilizer on corn plants.

The objective of the present research was to evaluate effects of different strip weed control associated with nitrogen fertilizer on corn applied after planting. The experiment was set and conducted in Botucatu, São Paulo State, Brazil, and the hybrid planted was Dekalb 333-B. A completely randomized block design with four replications was used. Experimental plots were disposed as a factorial scheme 2 x 2 x 4, constituted by two types of weeding on row (with or without manual hoeing), two types of weeding on inter-row (with or without manual hoeing), and four nitrogen levels applied after planting (00, 60, 90, and 120 kg ha(-1)). Plots were composed by six rows with 5 m length. Nitrogen fertilizer was applied at 35 days after emergence (d.a.e). For weed community it was evaluated: weed density, dominancy, frequency, and relative importance. The main weed species were: Brachiaria plantiginea, Amaranthus retroflexus, Bidens pilosa, Cyperus rotunds, Brachiaria decumbens, Euphorbia heterofila, Oxalis latifolia, Acanthospermum hispidum, Commelina benghalensis. It was evaluated corn height at 40 and 100 d.a.e., first ear insertion height at 100 d.a.e., and final grain yield at harvesting. Plants and first ear insertion height were affected when nitrogen fertilizer was not applied. Treatments without weed control showed that weed interfered negatively with plants height. There were no correlation between weeds and nitrogen fertilizer for all parameters evaluated. Parcels without weed showed the highest ear weights and final grain production. Treatments that received nitrogen fertilizer, independently of studied arrangement, provided higher yields.

Agriculture↗
PubMed2005

Weed seedbank evaluating method to generate spatial distribution maps.

The objective of this work was to develop a fast and practical method of weed seedbank evaluation to generate spatially distributed maps for use in site-specific weed management. Soil cores were collected at 0.20 m depth, air-dried, and then submitted to seedling growth in greenhouse. The sampling grid of 20 by 20 m was georeferenced by Global Positioning System, obtaining 73 soil cores with three replicates. During the greenhouse trial, there were two peaks of weed seedling growth: one in 119 days after water irrigation and another after KNO3 application. Weeds seedbank maps were obtained at different stages of seedling growth. The Pearson correlation was 0.99 for Brachiaria plantaginea seedbank map, 0.95 for Commelina benghalensis, and 0.85 for Cyperus rotudus generated at 119 days compared with 392 days after seedling growth in the greenhouse. The Brachiaria plantaginea seedbank map evaluated at 35 days presented correlation of 0.97 with 392 days. It was concluded that, for site-specific weed seedbank management, the evaluation of seedling growth in greenhouse until the first emergence peak is enough to generate weed seedbank maps.

Agriculture↗
PubMed1996

Analyzing the Light Energy Distribution in the Photosynthetic Apparatus of C4 Plants Using Highly Purified Mesophyll and Bundle-Sheath Thylakoids.

The chlorophyll fluorescence characteristics of mesophyll and bundle-sheath thylakoids from plant species with the C4 dicarboxylic acid pathway of photosynthesis were investigated using flow cytometry. Ten species with the NADP-malic enzyme (NADP-ME) biochemical type of C4 photosynthesis were tested: Digitaria sanguinalis (L.) Scop., Euphorbia maculata L., Portulaca grandiflora Hooker, Saccharum officinarum L., Setaria viridis (L.) Beauv., Zea mays L., and four species of the genus Flaveria. This study also included three species with NAD-ME biochemistry (Atriplex rosea L., Atriplex spongiosa F. Muell., and Portulaca oleracea L.). Two C4 species of unknown biochemical type were investigated: Cyperus papyrus L. and Atriplex tatarica L. Pure mesophyll and bundle-sheath thylakoids were prepared by flow cytometry and characterized by low-temperature fluorescence spectroscopy. In pure bundle-sheath thylakoids from many species with C4 photosynthesis of the NADP-ME type, significant amounts of photosystem II (PSII) emission can be detected by fluorescence spectroscopy. Simulation of fluorescence excitation spectra of these thylakoids showed that PSII light absorption contributes significantly to the apparent excitation spectrum of photosystem I. Model calculations indicated that the excitation energy of PSII is efficiently transferred to photosystem I in bundle-sheath thylakoids of many NADP-ME species.

Journal Article↗
PubMed1979

A Mechanism of Chlorosis Caused by 1,3-Dimethyl-4-(2,4-dichlorobenzoyl)-5-hydroxypyrazole, a Herbicidal Compound.

In organic solvents, 1,3-dimethyl-4-(2,4-dichlorobenzoyl)-5-hydroxypyrazole (DTP) converted chlorophyll a and b extracted from rice seedlings (Oryza sativa L. ;Kinmaze') into pheophytin a and b, respectively. On comparing the chlorophyll-converting activity of DTP to those of acetic, glycolic, 2,4-dichlorobenzoic, monochloroacetic, 2,6-dichlorobenzoic, pyruvic, and dichloroacetic acids, it was demonstrated that DTP induced H(+) into chlorophyll specifically. 5-Hydroxypyrazoles, which seem to be dissociable, converted chlorophyll into pheophytin in vitro. These compounds also induced chlorosis in sedge seedlings (Cyperus serotinus Rottb.), when the seedlings were grown in media containing these compounds. However, 5-hydroxypyrazoles, which seem to be undissociable, and analogs having no hydroxy group caused neither the chlorophyll conversion in vitro nor chlorosis in the seedlings. Chlorosis in barnyardgrass seedlings (Echinochloa crus-galli Beauv. var. oryzicola Ohwi) induced by DTP was reversed by cultivating the seedlings in media containing DTP plus NaOH, KOH, NH(4)OH, Ca(OH)(2), sodium acetate, sodium pyruvate, sodium succinate, or sodium fumarate. Accumulation of the vinyl pheoporphyrin fraction in 4- day-old etiolated radish cotyledons (Raphanus sativus L. ;Minowase 2') was enhanced by incubating the cotyledons with delta-aminolevulinic acid in the dark. However, simultaneous treatment with delta-aminolevulinic acid and DTP reduced accumulation of the fraction and promoted formation of the uro, copro, and protoporphyrin fractions. These results suggest that DTP blocks the synthesis of protochlorophyllide in intact plants and induces consequent chlorosis, and the H(+) -donating activity of DTP might cause the reduction of protochlorophyllide biosynthesis.

Journal Article↗
PubMed1979

Transport of divalent cations: cation exchange capacity of intact xylem vessels.

The cation exchange capacity of the intact xylem vessels in cut shoots of papyrus (Cyperus papyrus spec.) has been determined. The cation exchange capacity is independent of the cation concentration in the transpiration stream, and is equal for Ca and Co. The high value of the cation exchange capacity (0.6 to 1 x 10(-7) equivalents per square centimeter vessel wall surface) leads to the hypothesis that the porous structure of the vessel wall, and not only the inner vessel wall surface, acts as a cation exchanger.Differences between anion ([(32)P]phosphate, [(45)Ca]EDTA(2-), [(115)Cd(m)]-EDTA(2-)), and cation ([(45)Ca](2+), [(115)Cd(m)](2+)) movement are explained in terms of transport with the transpiration flux or by exchange reactions. The competition between exchange sites and natural or synthetic ligands for the divalent cations is discussed.

Journal Article↗
PubMed1997

Use of rDNA-PCR to investigate the ecological distribution of Anopheles bwambae in relation to other members of the An.gambiae complex of mosquitoes in Bwamba County, Uganda.

Environmental relationships were investigated among three species of the Anopheles gambiae complex of mosquitoes associated with the geothermal springs located in Bwamba County, Uganda. The degree of ecological isolation between An.gambiae and An.bwambae, a sibling species known only from the geothermal springs environment, was assessed on the basis of adult distribution and abundance as well as differences in larval habitats. Field data were gathered during June 1995 without knowing which of the species were being collected. Specimens identified subsequently by rDNA-PCR were used to interpret the ecological data. Ten of twenty aquatic sites sampled were found positive for immature stages of the An.gambiae complex. Larvae of An.bwambae were associated with 'springwater' habitats having much higher conductivity, much greater concentrations of dissolved solids and slightly higher temperature and pH than 'normal' fresh water sites inhabited by larvae of An.gambiae. Larval habitats of both species were unshaded: An.bwambae occurred among dense sedge (Cyperus laevigatus) whereas those of An.gambiae were almost devoid of vegetation. One mixed sample showed that larvae of both species occur together in peripheral aquatic sites with intermediate physical and ecological characteristics. In water preference tests, free-flying females were reluctant to lay eggs on bowls of water in cages; gravid females (with one wing amputated) placed on the surface of water in a cup laid eggs on seasoned rainwater (12/51 An.bwambae; 2/3 An.gambiae) as well as spring-water (39/51 An.bwambae; 1/3 An.gambiae). All three An.gambiae oviposited on the first water option, whereas 86% of An.bwambae witheld oviposition until being moved to the other type of water after 5-6 h, and 82% (36/44) of these laid eggs on geothermal water in preference to rainwater. Larval and adult collections showed tha An.gambiae occurs sympatrically with An.bwambae throughout its range in the humid foothill environment of the geothermal springs, whereas the distribution of An.arabiensis overlaps only slightly with An.bwambae towards the savanna environment north of the springs.

Animals↗
PubMed1969

Carbon dioxide compensation points in related plant species.

Both high and low C0(2) compensation concentrations were found in the plant genera-Panicum, Cyperus, and Euphorbia. Within each genus, however, high and low compensations were found in different subgenera. Thus, they may not be genetically closely related. No significant differences in CO(2) compensation were found among 100 genetic lines of Triticum aestivum L. or among 20 lines of Hordeum vulgare L.

Carbon Dioxide↗
PubMed2002

Studies on exudate-depleted sclerotial development in Sclerotium rolfsii and the effect of oxalic acid, sclerotial exudate, and culture filtrate on phenolic acid induction in chickpea (Cicer arietinum).

Exudate depletion from developing sclerotia of Sclerotium rolfsii Sacc. in culture caused reduced size and weight of sclerotia. Germination of exudate-depleted sclerotia was delayed on Cyperus rotundus rhizome meal agar medium when compared with that of control sclerotia. The exudate-depleted sclerotia caused infection in chickpea (Cicer arietinum) plants in a glasshouse. Different temperatures and incubation periods had no effect on the germination ability of the exudate-depleted sclerotia. Oxalic acid, sclerotial exudate, and culture filtrate of S. rolfsii induced the synthesis of phenolic acids, including gallic, ferulic, chlorogenic, and cinnamic acids, as well as salicylic acid, in treated chickpea leaves. Gallic acid content was increased in treated leaves compared with the untreated controls. Maximum induction of gallic acid was seen in both leaves treated with oxalic acid followed by exudate and leaves treated with culture filtrate. Cinnamic and salicylic acids were not induced in exudate-treated leaves. Ethyl acetate fractionation indicated that the sclerotial exudates consisted of gallic, oxalic, ferulic, chlorogenic, and cinnamic acids, whereas the culture filtrate consisted of gallic, oxalic, and cinnamic acids along with many other unidentified compounds.

Basidiomycota↗
PubMed2005

Hydrocarbon biodegradation in oxygen-limited sequential batch reactors by consortium from weathered, oil-contaminated soil.

We studied the use of sequential batch reactors under oxygen limitation to improve and maintain consortium ability to biodegrade hydrocarbons. Air-agitated tubular reactors (2.5 L) were operated for 20 sequential 21-day cycles. Maya crude oil-paraffin mixture (13,000 mg/L) was used as the sole carbon source. The reactors were inoculated with a consortium from the rhizosphere of Cyperus laxus, a native plant that grows naturally in weathered, contaminated soil. Oxygen limitation was induced in the tubular reactor by maintaining low oxygen transfer coefficients (k(L)a < 20.6 h(-1)). The extent and biodegradation rates increased significantly up to the fourth cycle, maintaining values of about 66.33% and 460 mg x L(-1) x d(-1), respectively. Thereafter, sequential batch reactor operation exhibited a pattern with a constant general trend of biodegradation. The effect of oxygen limitation on consortium activity led to a low biomass yield and non-soluble metabolite (0.45 g SS/g hydrocarbons consumed). The average number of hydrocarbon-degrading microorganisms increased from 6.5 x 10(7) (cycles 1-3) to 2.2 x 10(8) (cycles 4-20). Five bacterial strains were identified: Achromobacter (Alcaligenes) xylosoxidans, Bacillus cereus, Bacillus subtilis, Brevibacterium luteum, and Pseudomonas pseudoalcaligenes. Asphaltene-free total petroleum hydrocarbons, extracted from a weathered, contaminated soil, were also biodegraded (97.1 mg x L(-1) x d(-1)) and mineralized (210.48 mg CO2 x L(-1) x d(-1)) by the enriched consortium without inhibition. Our results indicate that sequential batch reactors under oxygen limitation can be used to produce consortia with high and constant biodegradation ability for industrial applications of bioremediation.

Bacteria↗
PubMed2002

Effects of Kangen-karyu on coagulation system and platelet aggregation in mice.

Kangen-karyu (KGK) is a herbal formula created under the theory of traditional Chinese herbal medicine to invigorate the blood and dispel blood stasis. It contains 6 herbs: peony root, cnidium rhizome, safflower, cyperus rhizome, saussurea root (JP XIV), and Salvia miltiorrhiza root. The present study has been conducted to evaluate the in vivo anti-thrombotic activity of KGK using normal mice. Three consecutive days of oral administration of KGK to mice significantly extended tail-bleeding time and suppressed ex vivo platelet aggregation, while it did not extend the prothrombin time of plasma. It was revealed that the anti-thrombotic effects of KGK did not depend on the downregulation of the coagulation system, but depended in part on the inhibition of platelet aggregation. These results explain one of the pharmacological activities of KGK to invigorate the blood and dispel blood stasis.

Animals↗
PubMed2006

Modelling and evaluation of nitrogen removal performance in subsurface flow and free water surface constructed wetlands.

With the aim of protecting drinking water sources in rural regions, pilot-scale subsurface water flow (SSF) and free water surface flow (FWS) constructed wetland systems were evaluated for removal efficiencies of nitrogenous pollutants in tertiary stage treated wastewaters (effluent from the Pasaköy biological nutrient removal plant). Five different hydraulic application rates and emergent (Canna, Cyperus, Typhia sp., Phragmites sp., Juncus, Poaceae, Paspalum and Iris) and floating (Pistia, Salvina and Lemna) plant species were assayed. The average annual NH4-N, NO3-N and organic-N treatment efficiencies were 81, 40 and 74% in SSFs and 76, 59 and 75% in FWSs, respectively. Two types of the models (first-order plug flow and multiple regression) were tried to estimate the system performances. Nitrification, denitrification and ammonification rate constants (k20) values in SSF and FWS systems were 0.898 d-1 and 0.541 d(-1), 0.486 d(-1) and 0.502 d(-1), 0.986 d(-1) and 0.908, respectively. Results show that the first-order plug flow model clearly estimates slightly higher or lower values than observed when compared with the other model.

Fresh Water↗
PubMed1979

Herbimycin, a new antibiotic produced by a strain of Streptomyces.

Herbimycin, a new antibiotic, was isolated from the fermentation broth of Streptomyces hygroscopicus strain No. AM-3672, a soil isolate. The molecular formula of herbimycin was determined to be C30H42N2O9. Herbimycin was found to have potent herbicidal activity against most mono- and di-cotyledonous plants, especially against Cyperus microiria STEUD. However, Oryza sativa showed strong resistance to herbimycin.

Animals↗
PubMed1991

Potential natural exposure of Mississippi sandhill cranes to aflatoxin B1.

A survey was conducted to determine if carcinogenic mycotoxins were present in foods consumed by Mississippi sandhill cranes (Grus canadensis pulla). Samples of field corn (Zea mays) (n = 111) and chufa (Cyperus esculentus) (n = 20), obtained in 1987, 1988 and 1989 on the Mississippi Sandhill Crane National Wildlife Refuge (MSCNWR) and nearby private lands were analyzed for aflatoxin B1(AB1), ochratoxin A and sterigmatocystin using thin layer chromatography. Chufa samples were negative for all three mycotoxins. Aflatoxin B1 was found in corn at concentrations from 5 to 5,000 ppb; the other mycotoxins were not found in corn. Contaminated corn was found in 72% of all corn fields, but the proportion of contaminated fields was 57 to 100% for the 3-yr period. Contamination with AB1 was greatest in corn obtained from the ground post-harvest. Overall, 32% of corn samples from the ground had levels greater than or equal to 200 ppb with a mean of 427 ppb (range = 5 to 5,000 ppb) in contaminated fields. In 1989, mean AB1 concentration in corn on the ground was 5 to 1138 ppb for individual fields. The concentration of AB1 was less than or equal to 200 ppb in all corn samples from upright stalks. The study demonstrated that AB1 is available to sandhill cranes and at levels that may pose a serious health threat.

Aflatoxin B1↗
PubMed1999

Treatment of complications due to peritoneal dialysis for chronic renal failure with traditional Chinese medicine.

In this paper, the experience in the treatment of complications due to continuous ambulatory peritoneal dialysis for chronic renal failure with traditional Chinese medicine (TCM) is reported. Modified Renshen Yangrong Tang (Ginseng Nutrition Decoction) was used for anorexia and hypoproteinemia; modified Xiangsha Liujunzi Tang (Decoction of Cyperus and Amomum with Six Noble Ingredients) for abdominal pain and distension; modified Da Chaihu Tang (Major Bupleurum Decoction) for peritonitis; modified Shenling Baizhu San (Powder of Ginseng, Poria and Atractylodes) for diarrhea due to insufficiency of the spleen with abundance of dampness; Lizhong Tang (Decoction for Regulating the Function of Middle-jiao) and modified Sishen Wan (Pills of Four Miraculous Drugs) for insufficiency of both the spleen and the kidney; Siwu Tang (Decoction of Four Ingredients) added with other drugs for cutaneous pruritus, and Guishao Sijunzi Tang (Decoction of Four Noble Drugs added with Chinese Angelica Root and white Peony Root) for renal anemia. The therapeutic principles of invigorating the liver and kidney, strengthening the bones and muscles, and promoting blood circulation to eliminate blood stasis were adopted in the treatment of renal osteopathy, and the therapeutic principles of invigorating the liver and kidney, expelling phlegm and resolving dampness, and promoting blood circulation to eliminate blood stasis in the treatment of hyperlipemia. Shen Tekang capsules (capsules for improving the renal function) was administered to patients for strengthening the viability and improving the nutrition state, and the recipe for treating renal function failure (both formulated by the authors) for improving the renal function so as to decrease the frequency and duration of dialysis.

Anorexia↗
PubMed1992

[Studies on the medicinal plant in the "Sambutsu-cho" of Bungo Province possessed by the Kumamoto Clan (II); studies on the medicinal herbs].

In the previous report, I studied the medicinal trees contained in the Sambutsu-cho of the Kumamoto clan in Bungo Province. In this report, I studied the medicinal herbs contained in the same book. There were 259 names in the herbal part. I identified 156 species and found 103 species as the medicinal plants. The ratio of the medicinal plants was 66%. The famous medicinal plants were as follows: Atractilodes japonica, Platycodon gradiflorum, Mentha arvensis var. piperascens, Lisospermum erythrorizon, Pharbitis nil, Gentiana scabra var. buergeri, Cnidium officianal, Angelica acutiloba, Bupleurum falcatum, Pueraria lobata, Paeonia lactiflora, Paeonia suffruticosa, Achyranthes fauriei, Asarum dimidiatum, Ophiopogon japonica, Pinellia ternata and Cyperus rotundus.

Botany↗