Antagonistic Activities of Selected Bacterial Isolates Against Soilborne Disease Pathogens of Turfgrass

Disease samples exhibiting symptoms of brown patch, yellow patch and Pythium blight were taken from several golf courses in Malaysia Isolation and identification of the pathogens indicated that Rhizoctonia solani Kuhn, Rhizoctonia cerealis Van der Hoeven and Pythium aphanidermatum (Edson) Fitzpatrick were the causal agents respectively. Identification of the pathogens was based on their morphological characteristics. Isolation of bacteria from thatch resulted in the isolation of ten bacterial isolates of which five were found to be antagonistic against the pathogens. The bacterial isolates were identified as Burkholderia cepacia (syn. Pseudomona. cepacia), Serratia marcescens, Chromobacterium violaceum, Pseudomonas aeruginosa and Bacillus megaterium. B.cepacia, P. aeruginosa and B. megaterium were found t

Potential antifungal activity of dioscorea daemona (ubi gadong) tuber extract against pyricularia grisea pathogen of rice blast disease / Neni Kartini Che Mohd Ramli and Khairun Nur Ali

Many of plants in Malaysia potentially can be used as bio fungicides. Dioscorea daemona(Ubi Gadong) has been used in traditional herbal medicine and as decoction in various areas for decades. Tuber extracts of this plant have also been reported to possess antifungal, antibacterial and antioxidant activities. Tuber crude extracts of D. daemona was consecutively separated into hexane, chloroform and methanol and screened for antifungal activities in vitro against Pyricularia grisea, pathogen of rice blast disease using well diffusion method on Potato Dextrose Agar. Results of this study showed that the methanol crude extract of D. daemona exhibited a very strong inhibitory activity against P. grisea with diameter of inhibition zone by 1.5cm (62.5% inhibition) at concentration 150,000ppm. Antifungal activities of most effective extracts were supported by the presence of chemical constituents such as alkaloids, saponin, flavonoids, terpenoids and phenol that were responsible for the antifungal activity. It could be inferred that methanol tuber extracts of D. daemonaat 150,000ppm concentration can serve as bio-fungicides against the growth of P. grise

In vitro study of antifungal activity of Entada spiralis Ridl. crude extract against dermatophytes of superficial skin disease

The antifungal activity of crude extracts from the stem bark of Entada spiralis was evaluated in vitro against human dermatophytes by disc diffusion method. Three types of human dermatophytes, known as Trichophyton mentagrophytes, Microsporum gypseum, Trichophyton tonsurans and one non-dermatophyteCandida glabrata, were tested against petroleum ether, ethyl acetate and methanol crude extracts of the E. spiralis. Results revealed that all dermatophytes were susceptible towards all tested crude extracts, whereas, the non-dermatophyte showed resistance to all the extracts. M. gypseum was found to be most susceptible towards petroleum ether extract (400mg/ml), with a zone of inhibition of 16 mm. The ethyl acetate and methanol crude extracts (400mg/ml each) exhibited highest activity against T. tonsurans with inhibition zones of 12.7 mm and 11.5 mm, respectively. Nystatin was used as the standard antifungal drug in all experiments and served as the positive control. All these results suggested that the petroleum ether crude extract was the most active extract against all tested dermatophytes except for C. glabrata. Based on these current findings, it can be concluded that the stem bark extracts of E. spiralis have promising antifungal activities and can be used as a potent antifungal drug against certain dermatophytes

Bioassay guided isolation of an antidermatophytic active constituents from the stembarks of entada spiralis ridl

Entada spiralis ridl (lenguminoceae) is a liana or woody climber that grows in the wild in Malaysia and is known locally as "Beluru" or "Sintok". The isolation and characterization of the chemical constituent from an active fraction of E. spiralis stem bark has been carried out. Our previous study revealed that methanol extract of E. spiralis stem bark exhibited promising antifungal activity against three dermatophyte strains, namely Trichophyton mentagrophytes ATCC 9533, Trichophyton tonsurans ATCC 28942 and Microsporum Gypseum ATCC 24102 that cause skin infection. This study was performed to elucidate the structure of active constituent known as ester saponin from the active fraction of E. spiralis stem bark. The factions were prepared using fractionation process and repeated antifungel test was conducted to identify the most active fraction. The structure elucidation of this compound was based on spectroscopis data (1H, 13C NMR, HMQC, HMBC and DEPT135) and comparison with literature. on the basis of spectroscopis analysis, the compound was identified as 28-α,L-rhamnopyranosyl-18,21,22-trihydroxy-12-en-29-(2-acetylamino-β-Dglucopyranosyl)triterpene ester. The current study provides important baseline information for the use of E. spiralis for the treatment of skin infection caused by the microorganism investigated in this study

In-vitro antidermatophytic activity of methanolic fraction from entada spiralis ridl. stem bark and its bioautographic profile

This study was performed to evaluate the antifungal activities of the methanolic fractions from the stem bark of Entada spiralis Ridl. against human dermatophytes and yeast-like fungus in in vitro. Three types of human dermatophytes and one yeast-like fungus namely Trichophyton mentagrophytes ATCC 9533, Microsporum gypseum ATCC 24102, Trichophyton tonsurans ATCC 28942, and Candida glabrata ATCC 66032 were tested against the methanolic fractions labelled as FA1, FA4 and FA5. First, the activities of antifungal were studied by disc diffusion method and broth micro dilution method. Second, we used an agar overlay bioautography assay to reveal antidermatophytic compounds of methanolic fractions. T.mentagrophytes, T.tonsuran and M.gypseum were susceptible towards all tested fractions in a concentration-dependent manner whereas C.glabrata was resistant. Fraction FA1 at a concentration of 400 mg/mL was found to exhibit highest antifungal activity with inhibition zone diameter of 22mm (T.mentagrophytes). FA1 showed MIC at 0.097 mg/mL while the MIC value for FA4 and FA5 were 3.12 mg/ml and 1.56 mg/ml respectively. Nystatin was used as standard antifungal drug and served as positive control. A garoverlay bioautography assay results showed that most of the bioactive compounds were 3 found in FA1. Based on these findings, it can be concluded that the stem bark extracts of E. spiralis can be a future source of potent natural antimicrobial drugs for superficial skin diseases

Phytochemical compound determination of Entada rheedei Spreng and its antifungal activity on selected soilborne fungal phytopathogens

This study presents the potential use of natural products from Entada rheedei Spreng. as biofungicide and their antifungal activity against five common soilborne fungal pathogens. The dried leaves, stems and seeds of E. rheedei were extracted by sequential extraction using petroleum ether, chloroform, methanol and water. Among the four solvents used, methanol (MeOH) was proven to be the best extracting solvent by giving the highest quantity of crude extract yielding 7.74g (3.87%) of stems crude extract, 1.861g (0.93%) of leaves crude extract and 26.6g (13.3%) of seed crude extract. The gained crude extracts were then screened via in vitro assays for their antifungal activity, using well diffusion method, against five selected soilborne fungal pathogens Rhizoctonia solani, Fusarium commune, Fusarium oxysporum f.sp. cubense (FOC), Pythium ultimum and Phytophthora palmivora. The petroleum ether and chloroform extracts of stems, seeds and leaves of E. rheedei failed to inhibit the growth of all tested soilborne fungal phytopathogens. The best inhibitory effect was elicited by the stems and seeds crude methanol extracts against Fusarium commune (51.4% and 50% radial growth inhibition respectively), while crude water and methanol extracts of seed against FOC showed the least significant effect (15% radial growth inhibition). Nevertheless, seed crude methanol and water extracts gave an impressive inhibitory on radial growth of F. commune with 50% and 36.7% inhibition respectively. Moreover, stem crude methanol and water extracts also showed moderately significant inhibitory against FOC (45% and 42.5% inhibitory respectively). The results also showed that all the stem and seed methanol and water crude extracts failed to inhibit the growth of R. solani, P. ultimum and P. palmivora. The Effective Inhibitory Concentration (EIC) of stem and seed crude methanol and water were determined at 100mg/mL. The phytochemical analysis of the active crude extracts revealed the presence of tannins, saponins, glycosides, triterpenoid, and alkaloid which only present in seed. Light and scanning electron microscopic observation on the effect of active crude extracts on spore germination and hyphal growth of F. commune and FOC illustrated that the spore and hyphae were collapsed and lysed; cell wall were degraded and shrank; while the spore (macroconidia) failed to germinate. The active crude extracts were further purified through Vacuum Liquid Chromatography (VLC) fractionation and resulted in the total of 22 fractions with 11 fractions for each stem and seed methanolic extracts. The obtained fractions were then screened for the antifungal activity against the selected soilborne fungal pathogens. Results showed some improvement on antifungal activity of the stem and seed methanolic fractions. The fraction eluted with chloroform: methanol in the ratio of 6:5 (F5) and 5:5 (F6) of stem methanol proved to be the most active fractions against F. commune (56.8% and 45.9% growth inhibition) and FOC (48.7% and 43.6% growth inhibition). All fractions of stem and seed methanolic extracts showed some improvement in their antifungal activity against R. solani and P. palmivora, which were not shown previously by any of their parent crude extracts. The TLC phytochemical analysis showed the presence of saponin and tannin in the fractions F4, F5, F6 and F7 of stem and seed methanolic extracts. The determination of major active compound in the active fractions via High Performance Liquid Chromatography (HPLC) analysis, to confirm the major constituent contained in the active fractions, showed that the active fractions (F4-F7) of stem and seed methanolic extracts of E. rheedei contain saponin as major active compound

Phytochemical compound determination of Entada rheedei Spreng and its antifungal activity on selected soilborne fungal phytopathogens

This study presents the potential use of natural products from Entada rheedei Spreng. as biofungicide and their antifungal activity against five common soilborne fungal pathogens. The dried leaves, stems and seeds of E. rheedei were extracted by sequential extraction using petroleum ether, chloroform, methanol and water. Among the four solvents used, methanol (MeOH) was proven to be the best extracting solvent by giving the highest quantity of crude extract yielding 7.74g (3.87%) of stems crude extract, 1.861g (0.93%) of leaves crude extract and 26.6g (13.3%) of seed crude extract. The gained crude extracts were then screened via in vitro assays for their antifungal activity, using well diffusion method, against five selected soilborne fungal pathogens Rhizoctonia solani, Fusarium commune, Fusarium oxysporum f.sp. cubense (FOC), Pythium ultimum and Phytophthora palmivora. The petroleum ether and chloroform extracts of stems, seeds and leaves of E. rheedei failed to inhibit the growth of all tested soilborne fungal phytopathogens. The best inhibitory effect was elicited by the stems and seeds crude methanol extracts against Fusarium commune (51.4% and 50% radial growth inhibition respectively), while crude water and methanol extracts of seed against FOC showed the least significant effect (15% radial growth inhibition). Nevertheless, seed crude methanol and water extracts gave an impressive inhibitory on radial growth of F. commune with 50% and 36.7% inhibition respectively. Moreover, stem crude methanol and water extracts also showed moderately significant inhibitory against FOC (45% and 42.5% inhibitory respectively). The results also showed that all the stem and seed methanol and water crude extracts failed to inhibit the growth of R. solani, P. ultimum and P. palmivora. The Effective Inhibitory Concentration (EIC) of stem and seed crude methanol and water were determined at 100mg/mL. The phytochemical analysis of the active crude extracts revealed the presence of tannins, saponins, glycosides, triterpenoid, and alkaloid which only present in seed. Light and scanning electron microscopic observation on the effect of active crude extracts on spore germination and hyphal growth of F. commune and FOC illustrated that the spore and hyphae were collapsed and lysed; cell wall were degraded and shrank; while the spore (macroconidia) failed to germinate. The active crude extracts were further purified through Vacuum Liquid Chromatography (VLC) fractionation and resulted in the total of 22 fractions with 11 fractions for each stem and seed methanolic extracts. The obtained fractions were then screened for the antifungal activity against the selected soilborne fungal pathogens. Results showed some improvement on antifungal activity of the stem and seed methanolic fractions. The fraction eluted with chloroform: methanol in the ratio of 6:5 (F5) and 5:5 (F6) of stem methanol proved to be the most active fractions against F. commune (56.8% and 45.9% growth inhibition) and FOC (48.7% and 43.6% growth inhibition). All fractions of stem and seed methanolic extracts showed some improvement in their antifungal activity against R. solani and P. palmivora, which were not shown previously by any of their parent crude extracts. The TLC phytochemical analysis showed the presence of saponin and tannin in the fractions F4, F5, F6 and F7 of stem and seed methanolic extracts. The determination of major active compound in the active fractions via High Performance Liquid Chromatography (HPLC) analysis, to confirm the major constituent contained in the active fractions, showed that the active fractions (F4-F7) of stem and seed methanolic extracts of E. rheedei contain saponin as major active compound

Isolation of the compounds from antimicrobial active fraction from the stem barks of Entada spiralis Ridl

Entada spiralis Ridl. which is locally known as Sintok or Beluru is a woody climber with a characteristic spiral stem. The stem bark is traditionally used as natural shampoo and body wash among Malays due to its high content of saponins and its medicinal properties. The methanol extract of the stem bark possess promising antimicrobial activity against some species of skin diseases caused microbes The extract was further fractionation with different solvent gradient and repeated test on dermatophytes were done. The most active fraction is chloroform: methanol(9:1(V/V)). From this fraction we managed to isolate five compounds. The structure elucidation of the compounds were based on spectroscopic data ( 1H and 13C NMR, HMQC, HMBC and DEPT135)

Structural elucidation of a major active compounds from the stem barks of Entada spiralis Ridl

Bioassay-guided isolation of methanol extract revealed that medium polar fraction of the extract contained a few compounds that inhibited the growth of dermatophytes skin caused diseases. This confirmed the traditional usages of the stem barks of Entada spiralis by Malays in the old time, as a soap, shampoo and scrub during the treatment of skin problems. Minimum inhibitory concentration of the fraction gave a significant value for the effect on selected dermatophytes which are T. rubrum, T. mentagrophytes and M. gypseum. Out of the five bioactive compounds isolated we will discuss one(1)of the compound which is proposed as a novel compound. The structural elucidation of the compound were based on spectroscopic analysis by using 1H-NMR, 13CNMR, DEPT, HMBC and HMQC. The mass spectrum, FTIR and UV were also used to support our data. From the structural elucidation,the compound is suggested as a triterpenoidal saponin which has never been reported elsewhere