Medicinal plants are traditionally used for the treatment of human infections. The present study was undertaken to investigate Bergenia ciliata, Jasminum officinale, and Santalum album for their potential activity against human bacterial pathogens.
B. ciliata, J. officinale, and S. album extracts were prepared in cold and hot water. The activity of plant extracts and selected antibiotics was evaluated against five bacterial pathogens including Staphylococcus aureus, Bacillus subtilis, Proteus vulgaris, Pseudomonas aeruginosa, and Escherichia coli using agar well diffusion method.
Among the three medicinal plants, B. ciliata extracts displayed potential activity against bacterial pathogens. Cold water extract of Bergenia ciliate showed the highest activity against B. subtilis, which is comparable with a zone of inhibition exhibited by ceftriaxone and erythromycin. J. officinale and S. album extracts demonstrated variable antibacterial activity. Further studies are needed to explore the novel antibacterial bioactive molecules.
Fifteen batches of stirred youghurt were made to study the effect of microentrapment on the viability of bifidobacteria and their ability to inhibit the growth ofE. coliandStaph. aureus. Entrapped cells ofBifidobacterium bifidumandBifidobacterium infantiswere able to produce antimicrobial agents which inhibitedE. coliandStaph. aureusused as test organisms. Viable counts of unentrapped bifidobacteria decreased sharply, while entrapped cells of bifidobacteria were quite stable during refrigerated storage of stirred yoghurt.Bif. infantiswas more tolerant to storage conditions thanBif. bifidum. Microentrapment of bifidobacteria improved their survival during storage of stirred yoghurt, especiallyBif. bifidum, whose viability was not significantly (P≯0.05) different from entrappedBif. infantis. Viable counts ofE. colidecreased during storage of stirred yoghurt. Addition to bifidobacteria caused a sharp decrease in the viability ofE. coli.E.coligrowth was not detected at the 5th day, when entrapped cells of bifidobacteria were added to stirred yoghurt, whileE. coligrowth was not detected at the 7th day of storage in yoghurt containing unentrapped bifidobacteria. Addition ofBif. bifiduminhibited the growth ofE. colimore effectively thanBif. infantis. Staph. aureusshowed similar patterns toE. coli, except theStaph. aureuswas more tolerant to storage conditions. The counts of total bacteria, lactobacilli andStreptococcus salivariussubsp.thermophilusincreased up to the third day then declined till the end of storage. Titratable acidity increased gradually during the first 3 days of storage then increased slightly up to the end of storage, while pH values dropped during storage. Adding bifidobacteria,E. coliandStaph. aureusdid not affect significantly (P≯0.05) the counts of lactobacilli andStr. salivariussubsp.thermophilus, acidity and pH value.
Potential virulence factors of 9 saprophytic and 12 clinical Trichoderma longibrachiatum strains were examined in the present study, in order to compare their capacity to cause infection in humans. All of the strains were able to grow at temperatures up to 40 °C and at pH values ranging from 2.0 to 9.0. Carbon and nitrogen source utilization experiments revealed that all of the strains were able to utilize a series of basic amino acids both as sole carbon and nitrogen sources. The MIC values of the tested antifungal drugs were found to be 0.016-8 µg/ml for amphotericin B, 64-256 µg/ml for fluconazole, 0.5-32 µg/ml for itraconazole and 0.008-1 µg/ml for ketoconazole in the case of the examinedis olates. Metabolites of the strains inhibited the growth of different bacteria, furthermore, compounds produced by three clinical isolates reduced the motility of boar spermatozoa, indicating their toxicity to mammalian cells as well. On the whole, there were no significant differences in the examined features between strains derived from clinical or soil samples. The question, however, whether all environmental Trichoderma longibrachiatum strains have the capacity to cause infections or not, remains still unanswered.
-Mechiche, K., Gardan, L., Normand, P., Jouan, B. (2000) DNA relatedness among strains of
pathogenic to potato in France: description of three new species,
sp. nov. and
sp. nov. associated with
The proportion of pathogenic microorganisms in the microbial world is relatively small, while its threat to human health, economic development and social stability is severe. Infectious diseases are newly emergent
The evolution of anthracnose symptoms on the aerial part (leaves, stems and strawberries) of three varieties Fortuna, Camarosa and Festival of strawberry plants inoculated with the conidial suspensions of Colletotrichum acutatum and Colletotrichum gloeosporioides isolates was followed. The severity index and infection coefficients increased in function of time. Seven days after inoculation they were low not exceeding 13.43% and 43.33, but they increased four weeks after inoculation, respectively, to 37.96% and 99 on strawberry plants of the Camarosa variety, 54.44% and 105 on those of Fortuna and 51.12% and 85 on those of Festival. At the sixth week, the severity index and infection coefficients became very high, reaching respectively 100% and 408 on Fortuna plants inoculated with C. gloeosporioides isolate (Coll3) followed by Coll2 (89.28% – 300), Coll1 (86.66% – 378) and Coll4 (80.45% – 198) of C. acutatum species. Similarly, the isolate Coll3 caused fruit rot; the percentage of rotten strawberries was 100% on Fortuna variety, 83.33% on Festival and 70.25% on Camarosa. A positive re-isolation of the tested Colletotrichum isolates has been noted from leaves of strawberry varieties and negative from crowns or the roots. A significant to moderate reduction in fresh and dry weights of the aerial part and roots was noted in inoculated strawberry plants compared to the control.
in humans, leading to a wide spectrum of clinical manifestations, while Borrelia lusitaniae , Borrelia valaisiana and Borrelia bissettii , have been sporadically detected in humans, but their pathogenic potential is still unclear [ 1 ]. To date