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PubMed2002

Inhibition of growth, enterotoxin production, and spore formation of Clostridium perfringens by extracts of medicinal plants.

The extracts of 14 plants used in the traditional medicine of Mexico were evaluated for their effects on the growth, spore formation, and enterotoxin production of Clostridium perfringens type A. The extracts of Psidium guajava L., Haemotoxylon brasiletto, and Euphobia prostata were the most effective inhibitors of growth, spore formation, and enterotoxin production. No enterotoxins were detected when extracts were added to the media at less than the MIC for growth.

Clostridium perfringens↗
PubMed2004

Evaluation of phytochemical and antimicrobial properties of leaf extract of Tapinanthus sessilifolius (P. Beauv) van Tiegh.

Leaf extracts of T. sessilifolius growing on five different host plants (Psidium guajava, Citrus lemon, Vernonia amygdalina, Persea americana and Jatropa curcas) were evaluated for antimicrobial activity of the plant. Powdered leaves of T. sessilifolius collected from each host plant was divided into two portions. One portion was used for aqueous infusion and the other portion was successively extracted with hexane, ethylacetate and methanol. Infusion of aqueous extract of powdered leaves did not show antimicrobial effect even at the concentration of 1000 and 2000 microg/ml on test microorganisms (Staph. aureus, E. coli, Bacillus subtilis, Pseudomonas aeruginosa and Candida albicans). However in broth culture, methanolic and hexane extract had MIC range of 62.5-500 microg/ml and ethylacetate extract had 250-500 microg/ml. Phytochemical screening of leaf samples of T. sessilifolius collected from different host plants showed positive test for hydrolysable tannins, saponins, flavonoids, terpenes, cardiac glycoside, reducing sugars and proteins. LD50 concentration was found to be > 1.500 mg/kg for samples from P. guajava; 489.89 mg/kg for J. curcas and C. lemon; and 692 mg/kg for V. amydalina in mice.

Agar↗
PubMedDate not supplied

[Lethal effect of Cuban Myrtaceae on Aedes aegypti (Diptera Cuilicidae)].

The biological activity of the essential foliar oils from 2 Cuban endemic Myrtaceae: Eugenia melanadenia and Psidium rotundatum on A. aegypti larvae was evaluated for the first time at the laboratory level. The probit-log analysis of the results showed the larvicidal effect of both oils with values of CL50 = 0.0085% and CL95 = 0.0104% for E. melanadenia and CL50 = 0.0063% and CL95 = 0.0071% for O. rotundatum. Besides, the diagnostic concentration for both essential oils are given and the possible implications of these findings on field populations of A. aegypti are suggessted.

Aedes↗
PubMed2000

Antifungal activity of plant extracts against Arthrinium sacchari and Chaetomium funicola.

Various plant extracts were examined for antifungal activity with the objective of improving the commercial sterility of aseptically filled tea beverage products in PET bottles. When the hot water extract and the methanol extract of 29 samples were measured for their antifungal activity against Arthrinium sacchari M001 and Chaetomium funicola M002 strains, five samples, Acer nikoense, Glycyrrhiza glabra, Lagerstroemia speciosa, Psidium guajava and Thea sinensis, showed high activity. Of these, the extracts from A. nikoense, G. glabra and T. sinensis were fractionated by extraction with CHCl3, and the CHCl3-soluble fractions from G. glabra showed antifungal activity with minimum inhibitory concentrations (MICs) between 62.5 and 125 microg/ml against the above-mentioned two fungi. When the EtOAc-soluble fraction of A. nikoense was used, the MIC against A. sacchari M001 was 62.5 microg/ml. However, none of the fractions from A. nikoense or T. sinensis showed high activity against C. funicola M002 and their MICs were greater than 500 microg/ml. A licorice preparation made from the commercially available oil-based extract of G. glabra showed a low MIC of 25 microg/ml against five tested strains of filamentous fungi, but not against Aspergillus fumigatus M008, in a blended tea. Consequently, the possibility of adding a licorice preparation made from the oil-based extract of G. glabra to tea beverages (aseptically filled into PET bottles) was suggested.

Journal Article↗
PubMedDate not supplied

[Biological evaluation of Cuban plants. II].

The study of the antimicrobial activity of aqueous, alcoholic and ketonic extracts from different parts of five superior, dried, grinded and defatted plants of the families Myrtaceae, Polypodiaceae and Zingiberaceae is pursued. Good results were obtained from Psidium guajaba leave and stem ketonic extracts as well as from Costus spicatus leave and root alcoholic extracts.

Anti-Bacterial Agents↗
PubMed1993

Retroviral reverse transcriptase inhibitory activity in Thai herbs and spices: screening with Moloney murine leukemia viral enzyme.

Fifty-seven Thai herbs and spices were examined for their retroviral reverse transcriptase inhibitory activity. All herbs and spices were extracted with hot-water and methanol. Reverse transcriptase inhibitory activity of the extracts was determined by using Moloney Murine Leukemia Virus reverse transcriptase (M-MuLV-RT) reacted with 3H-dTTP and radioactivity measured with a scintillation counter. Eighty-one per cent (46/57) of hot-water extracts and 54% (31/57) of methanol extracts showed inhibitory activities. At a concentration of 125 micrograms/ml, 13% (6/46) of hot-water extracts, namely Eugenia caryophyllus Bullock et Harrison, Phyllanthus urinaria Linn., Terminalia belerica Roxb., Nelumbo nucifera Gaertn., Psidium guajava Linn. and Lawsonia inermis Linn., had a relative inhibitory ratio (IR) over 50%. They showed ratios of 100%, 91%, 75%, 74%, 61% and 60%, respectively. For methanol extracts, only 10% (3/31) had IR values over 50%. They were T. belerica, E. caryophyllus and N. nucifera which exhibited IR values of 83%, 54% and 54%, respectively.

Animals↗
PubMedDate not supplied

[In vitro effect against Giardia of 14 plant extracts].

OBJECTIVE: To investigate antigiardiasic activity in plants used in Mexico as antidiarrheics and/or antiparasitics. MATERIALS AND METHODS: Fourteen species were evaluated. The antigiardiasic activity was measured in vitro in a blinded fashion using trophozoites of Giardia duodenalis incubated with plant extracts. The viability of trophozoites was ascertained using MTT (3-[4,5-dimethylthiazol-2-il]-2, 5-diphenyl tetrazolium bromide) which is reduced to MTT-formazan by the activity of live trophozoites. The reduced MTT was extracted with an acidified alcohol (2-propanol with HCI 0.04 M) and measured in a spectrophotometer at 570 nm. Negative (trophozoites without extract) and positive controls (incubated with tinadazol) were included. RESULTS: The scientific and trivial names of the plants are given (trivials in Spanish marked by an asterisk). They had the following trophozoite mortality (mean +/- SD in percent): Justicia spicigera (muicle*) = 91 +/- 0.5; Lipia beriandieri (oregano) = 90 +/- 0.6; Psidium guajava (guava) = 87 +/- 1.0; positive control of tinidazol = 79 +/- 1.9; Punica granutus (granado*) = 78 +/- 1.3; Magnifera indica (mango) = 77 +/- 1.0; Plantago major (lante*) = 76 +/- 1.2; Cupressus semperbirens (cipres) = 73 +/- 1.2; Castella tormentosa (chaparro amargoso*) = 70 +/- 0.7; Hematoxilon campechanum (palo de Campeche*) = 67 +/- 1.2. Without or with a low mean activity were Prosopis juliflora (mesquite*) and Rizophora mangle (mangle*) with 0%, Oriza sativa (rice) with 5%, Capsicum annum (pimiento*) with 21% and Persea americana (avocado) with 23%. There were no associations of the antigiardiasic effect with concentration or osmolality of the extracts. CONCLUSIONS: A clear in vitro antigiardiasic effects was seen in nine species. Three of them were superior to tinidazol which is a drug of common use in the treatment of giardiasis.

Animals↗
PubMed2004

In vitro availability of minerals of some tropical and citrus fruits as influenced by antinutritional factors.

Four tropical fruits and three citrus fruits were analyzed for moisture, ash, antinutritional factors (phytate, oxalate, and polyphenols) contents, and total and available minerals. Moisture contents ranged from 6.0 to 83.17% for tropical fruits while that of citrus fruits ranged from 88.20 to 89.50%. Ash contents ranged from 2.56 to 4.50% and from 3.83 to 4.83%, for tropical and citrus fruits, respectively. All fruits contained no oxalate while phytate and polyphenols ranged from 48.1 to 134.1 mg/ 100 g and from 0.115 to 0.34%, respectively. For all fruits major minerals contents ranged from 7.7 to 433.3 while trace ones ranged from 0.116 to 1.91 mg/100 g. In vitro availabilities of major minerals (% of total) varied from 11.1 to 86.2% while for minor ones it ranged from 13 to 72.5%.

Biological Availability↗
PubMed2006

Monitoring of pesticide residues in fruits.

Fruit samples of ber, grapes and guava analysed for pesticide residues employing multiresidue analysis by gas liquid chromatography equipped with ECD and NPD detectors and capillary columns showed contamination with organochlorine, synthetic pyrethroid and organophosphate insecticides. Among organochlorines, HCH, DDT and endosulfan were detected in almost all the samples. Residues of HCH and DDT were maximum in ber followed by grapes and guava where as of endosulfan were maximum in guava followed by grapes and ber. All the fruit samples showed the presence of residues with one or the other group of pesticides. Residues of none of the pesticides exceeded the MRL values in any sample. On the basis of these studies, it is suggested that monitoring studies should be extended to other fruits grown in different agro climatic regions which may serve as basis for future policy in chemical use.

Environmental Monitoring↗
PubMed2004

Methyl jasmonate treatments reduce chilling injury and activate the defense response of guava fruits.

Tropical fruits cannot be stored at low temperatures due to the chilling injury phenomena. With the goal of reducing the chilling injury, we tested 10(-4) and 10(-5) M of methyl jasmonate (MJ) treatment before the storage of red and white cultivars of guava fruits at 5 degrees C for up to 15 days plus two days at 20 degrees C. Every five days, we evaluated chilling injury index, ion leakage percentage, vitamin C, sugars, total phenols, and the activity of the enzymes lipoxygenase (LOX) and phenylalanine-ammonia lyase (PAL). We found that methyl jasmonate treatments reduce the chilling injury index and the ion leakage percentage. Furthermore, MJ did not affect vitamin C, chlorophyll, and total phenols. MJ increased sugar content, PAL, and LOX activities. We concluded that MJ reduces chilling injury and activates the fruit defense response as indicated by the behavior of total phenols and the increase in sugar content, PAL, and LOX activities.

Acetates↗
PubMed2005

Enhanced flavour extraction in continuous liquid-liquid extractors.

Continuous liquid-liquid extraction is a versatile, reliable and robust sample preparation technique, but there is a tendency for the solvent to make channels through the sample, causing uneven and incomplete extraction. A simple, cheap magnetic stirrer that prevents channelling improves extraction efficiency by between 2.8 and 17.6 times.

Ananas↗
PubMed2005

Functional properties of guava seed glutelins.

Five guava seed glutelin extracts were obtained with different buffer solutions: Na(2)B(4)O(7) alone (Glut.Bo) or containing SDS (Glut. BoSDS), 2-mercaptoethanol (Glut.Bo2-ME), or a combination of both (Glut. BoSDS2-ME) and NaOH (Glut.Na). All borate buffer solutions were at pH 10. The higher yield of glutelins corresponded to the Glut. BoSDS extract (81.9% dry basis) and the lower to Glut.Bo (6.8%). The functional properties of the five guava seed glutelin extracts were determined. Glut. BoSDS, Glut. BoSDS2-ME, and Glut.Na showed high values for several properties, including surface hydrophobicity (7.7, 10.8, and 0.6, respectively), solubility at pH 10 (91.1, 77.9, and 96.7, respectively), water-holding capacity at pH 3.6 (1.7, 2.5, and 2.8, respectively), emulsifying activity index (pH 10; 503.5, 238.2, and 838.0, respectively), and foaming properties (pH 10; V(0) = 0.14, 0.25, and 0.19, respectively; V(max) = 6.1, 5.59, and 4.51, respectively; t(1/2) = 266, 255.3, and 94 s, respectively). These results suggest that the denaturing reagent (SDS or NaOH) during extraction conferred on the proteins a structure that facilitated the development of their functional properties.

Chemical Phenomena↗
PubMed2003

Comparison of cross inoculation potential of South African avocado and mango isolates of Colletotrichum gloeosporioides.

Three hundred and eighteen Colletotrichum gloeosporioides isolates from stem-end rot and anthracnose infected avocados as well as from stem-end rot/anthracnose and soft brown rot on mango, were compared using fruit inoculations. Isolates could be categorised according to lesion size and both avocado and mango isolates produced larger lesions when inoculated on their own hosts. Cross-inoculation potential of these isolates was also compared on strawberries, peppers, guavas, papayas and citrus. All isolates produced lesions on all hosts except citrus. Factors such as area of origin and symptom type from which original isolations were made, could not be correlated with lesion development on these hosts.

Capsicum↗
PubMed2005

Analysis of volatile compounds in some typical Brazilian fruits and juices by SPME-GC method.

This paper describes the analysis of volatile organic compounds (VOC) in typical Brazilian fruit and fruit juices by a solid-phase microextraction (SPME) method using a capillary gas chromatography system with flame ionization detection and mass spectrometry (GC-MS). A SPME holder with a 100-microm polydimethilsiloxane fibre coating was utilized. The optimal conditions were desorption at 220 degrees C for 1 min, absorption at 50 degrees C for 20 min and 4.00 ml of sample in the headspace vial. The method gave good precision and showed a linear response. More than 100 VOC were identified in the fruit and juices studied by GC-MS. The method was employed to quantify ethanol, naphthalene and benzoic acid in four different species of Brazilian fruit and their juices.

Anacardium↗
PubMed2000

Volatile host fruit odors as attractants for the oriental fruit fly (Diptera: Tephritidae).

We examined the responses of oriental fruit flies, Bactrocera dorsalis Hendel, to the odors of different stages and types of fruit presented on potted trees in a field cage. Females were most attracted to odors of soft, ripe fruit. Odors of common guava were more attractive to females than papaya and starfruit, and equally as attractive as strawberry guava, orange, and mango. In field tests, McPhail traps baited with mango, common guava, and orange captured equal numbers of females. Traps baited with mango were compared with 2 commercially available fruit fly traps. McPhail traps baited with mango captured more females than visual fruit-mimicking sticky traps (Ladd traps) and equal numbers of females as McPhail traps baited with protein odors. Results from this study indicate that host fruit volatiles could be used as lures for capturing oriental fruit flies in orchards.

Animals↗