In-Vitro Study of Biofungicidal Effects of Cassia alata Leaf Extracts on Some Pathogenic Organisms of White Yam (Dioscorea rotundata) Tuber in Storage

Bio-Research ◽  
2011 ◽  
Vol 8 (2) ◽  
Author(s):  
SC Eze ◽  
EI Eze
Author(s):  
A. C. Amadioha ◽  
Kenkwo Promise Chidi

Phytochemicals are biologically active naturally occurring chemicals produced by plants to help them thrive or thwart competitors or pathogenic organisms. The phytochemical experiment revealed varying degrees of flavonoid, alkaloid, saponin, tanin and phenol as naturally occurring bioactive chemicals of water and ethanol leaf extracts of Piper guineense, Cassia alata, Tagetes erecta and Ocimum graticimum. T. erecta had the highest flavonoid, alkaloid, saponin and tanin content of 3.17%, 5.43%, 3.50% and 5.15% respectively in ethanol extract and this was significant (P≤ 0.05), and followed by C. alata, O. graticimum, and P. guineense. The highest phenol content of 3.50% was recorded in water extract of C. alata followed by water extract of T. erecta, O. graticimum, and ethanol extract of P. guineense. The exploitation of antimicrobial potentials of these phytochemicals in the control of plant diseases incited by pathogenic organisms is recommended.


2019 ◽  
Vol 54 (1) ◽  
pp. 1-9
Author(s):  
E. N.K. Sowley ◽  
F. Kankam ◽  
R. M. Nsarko

Rots in yam tubers are the dominant cause of postharvest losses. Therefore, studies were con­ducted to identify the rot-causing organisms in yam and to evaluate the efficacy of false yam (Icacina oliviformis) plant extracts as surface protectants in the storage of yam. The experiment was laid out in a completely randomized design (CRD) design with five treatments (fruit, root and leaf extract of false yam, Mancozeb and tap water) replicated three times. Two concen­trations (50% and 100%) of each extract were also tested. Species were identified based on the structural features, the characteristics and properties of the spore and mycelium. A spore suspension of yam rot fungi was sprayed on healthy yam tubers that had been pretreated with the extracts. Results showed that fungi isolated from rotted yams were Aspergillus niger, A. fla­vus and Penicillium sclerotigenum. Leaf extracts (both 50% and 100%) had the highest growth inhibitions on all the three fungi isolated in vitro. Tubers treated with root and leaf extracts of false yam had a decreased tuber rot lengths of 1.80 mm2 and 2.17 mm2, respectively. The leaves and roots of false yam can be used as a surface protectant of yam in place of Mancozeb. Keywords: Icacina oliviformis; Dioscora rotundata; Mancozeb; Pathogenicity; Aspergillus spp.


Author(s):  
Michael Russelle Alvarez ◽  
Paolo Robert Bueno ◽  
Raymond Oliver Cruz ◽  
Richard Macapulay ◽  
Francis Jayson Vallesfin ◽  
...  

Plant-derived digestive enzyme inhibitors particularly those targeted to carbohydrate metabolism has been the focus of recent studies as natural supplements for weight control and diabetes. The present study explores the salivary amylase inhibition activity of Garcinia mangostana (Linn.) pericarp extracts and Carica papaya (Linn.) leaf extracts and fractions, as well as perform phytochemical screening and quantification, and thin layer – and high performance liquid chromatographic profiling. ­Results show that crude extracts and purified fractions were able to inhibit salivary amylase, with C. papaya fraction 1 being the most active at 30.89% inhibition. Phytochemical screening of all extracts tested ­positive for tannins, glycosides, phenolics, flavonoids and alkaloids. Quantification of phenolics showed that extracts contained high levels of phenolics, with C. papaya crude extract having the highest content with 219.0±12.7 mg GAE/g extract followed by G. mangostana crude extract with 247.1±18.0 mg GAE/g extract. Quantification of total flavonoids also showed C. papaya crude extract to contain the highest content with 55.12±0.679 mg QE/g extract. All extracts contained negligible alkaloid content, though. HPLC and TLC profiling showed several peaks and bands, when viewed in 210 nm and UV light, respectively. These results demonstrate in vitro the salivary amylase inhibitory activity of both plants and their potential as antidiabetic drug candidates; however, further studies need to be done, like isolation and structure elucidation of active components and toxicity assays. Keywords: Amylase inhibition, phytochemical quantification, Carica papaya, Garcinia mangostana


Author(s):  
Shubhaisi Das ◽  
Sunanda Burman ◽  
Goutam Chandra

Background: The only remedy for up surging problem of antibiotic resistance is the discovery of antibacterial agents of natural origin. Objective: The present study was aimed at finding antibacterial potential of crude and solvent extracts of mature leaves of Plumeria pudica. Methods: Antibacterial activity of three different solvent extracts were evaluated in four human and four fish pathogenic bacteria by measuring the zone of inhibition and determining Minimum Inhibitory Concentration and Minimum Bactericidal Concentration values. Standard antibiotics were used as positive control. Preliminary phytochemical screening of most effective extract i.e., ethyl acetate extract, Fourier Transform Infra Red analysis and GC-MS analysis of the Thin Layer Chromatographic (TLC) fraction of ethyl acetate extract were done meticulously. All experiments were done thrice and analyzed statistically. Results: Crude leaf extracts and solvent extracts caused good inhibition of bacterial growth in all selected bacteria. Ethyl acetate extract showed highest inhibition zones in all tested strains with maximum inhibition (19.50±0.29 mm) in Escherichia coli (MTCC 739). MBC/MIC of the extracts indicated that all three solvent extracts were bactericidal. Preliminary phytochemical tests revealed the presence of tannins, steroids and alkaloids and FT-IR analysis revealed presence of many functional groups namely alcoholic, amide, amine salt and aldehyde groups. From the GC-MS analysis of TLC fraction of ethyl acetate extract five different bioactive compounds e.g., 2,4-ditert –butylphenyl 5-hydroxypentanoate, Oxalic acid; allyl nonyl ester, 7,9-Ditert-butyl-1-oxaspiro(4,5)deca-6,9-diene-2,8-dione, Dibutyl phthalate and 2,3,5,8-tetramethyl-decane were identified. Conclusion: Leaf extracts of P. pudica contain bioactive compounds that can be used as broad spectrum bactericidal agent.


Sign in / Sign up

Export Citation Format

Share Document