Arshad Javaid

Continuous microwave-assisted flow synthesis has been used as a simple, more efficient, and low-cost route to fabricate a range of nanosized (2+ ion source) and diammonium hydrogen phosphate at pH 10 with a time duration of 5 min. The morphological characterization of the obtained powder has been carried out by employing techniques such as transmission electron microscopy, X-ray diffraction, and Brunauer–Emmett–Teller surface area analysis. The chemical structural analysis to evaluate the surface properties was made by using X-ray photoelectron spectroscopy. Zeta potential analysis was performed to evaluate the colloidal stability of the particles. Antimicrobial studies were performed for all the compositions using four bacterial strains and an opportunistic human fungal pathogen Macrophomina phaseolina. It was found that the nanoproduct with high strontium content (15 wt% of strontium) showed pronounced antibacterial potential against M. luteus while it completely arrested the fungal growth after 48 h by all of its concentrations. Thus the synthesis strategy described herein facilitated the rapid production of nanosized Sr-substituted CaPs with excellent biological performance suitable for a bone replacement application.

Background: Mung bean is a pulse crop of economic significance, grown in Pakistan for its edible seeds. Its production is severely affected by Macrophomina phaseolina, a necrotrophic pathogen. This study was carried out to investigate the effect of different biocontrol fungi on expression of IPER gene in mung bean plants inoculated with M. phaseolina.Methods: Pot trials were carried out by adding different concentration of dry biomass of quinoa (DBQ) and six antagonistic fungi viz. Aspergillus flavipes, Aspergillus versicolor, Penicillium digitatum, Penicillium italicum, Trichoderma pseudokoningii and Trichoderma viride in M. phaseolina infected soils. After four weeks of germination of mung bean seeds, RNA was extracted from roots and leaves by using TRIzol method and cDNA was prepared by using SuperScriptTM IV First-Strand Synthesis Kit. IPER gene expression was studied on qRT-PCR and ACT was used as a housekeeping gene.Results: The expression of IPER gene was higher in positive control (only inoculated with M. phaseolina) than in negative control (no amendment). Moreover, 1 and 2% doses of DBQ showed slightly higher Ct values than in 3% dose where it was dropped down indicating the allelopathic stress of DBQ treated soils. The treatments either with sole application of antagonistic fungi or together with DBQ showed much higher Ct values indicating no stress at all.Conclusion: Plants only inoculated with M. phaseolina showed the highest disease incidence as compared to the negative control. The soils amended with DBQ and antagonistic fungi significantly alleviated the effect of M. phaseolina. The treatments with increased pathogen stress showed reduced Ct values and vice versa.Keywords: Biocontrol; IPER gene; Gene expression; Macrophomina phaseolina; Mung bean

Background: Chenopodium quinoa Willd. or quinoa is an important food crop, having many pharmacological properties. It is recently introduced in Pakistan. In the present study, a phytochemical profile of its leaf extract was assessed through GC-MS analysis, and the health-related compounds were identified through a literature survey.Methods: Quinoa was grown in Lahore, Pakistan, and its leaves were collected at maturity, dried, ground, and extracted in methanol. GC-MS analysis of this extract was done that showed the presence of 30 compounds.Results: The most abundant compound was α-linolenic acid (12.13%), followed by n-hexadecanoic acid (11.51%), ergosta-5,7-dien-3-ol, (3β)- (10.99%), phytol (10.25%), and stigmast-7-en-3-ol, (3.beta.,5.alpha.,24S)- (7.33%). Moderately occurring compounds included DL-proline, 5-oxo-, methyl ester (6.01%), hydroxylamine, O-pentyl- (5.38%), neophytadiene (4.36%), 2-methoxy-4-vinylphenol (3.96%), 2-isopropoxyethyl propionate (3.84%), vitamin E (2.52%), and linolenic acid, methyl ester (2.46%). The remaining compounds were less abundant, having peak areas of less than 2%.Conclusion: Literature survey revealed that α-linolenic acid; n-hexadecanoic acid; phytol; squalene, vitamin E and linolenic acid, and methyl ester; present in leaf extract of quinoa possess various health-related properties such as antibacterial, antifungal, cardio-protective, anti-inflammatory, hypocholesterolemic, antihistaminic, antiandrogenic and antieczemic. Keywords: Amaranthaceae; Bioactive compounds; Leaf extract; Pakistan; Quinoa

An in vitro study was conducted to assess the antifungal efficacy and potential antifungal compounds of n-butanol fraction of methanolic stem extract of Chenopodium murale L. against Fusarium oxysporum f. sp. lycopersici. In order to get n-butanolic fraction, the methanolic extract was partitioned using n-hexane, chloroform and ethyl acetate to separate non-polar and low polarity compounds. Finally, n-butanol fraction was separated and its 8 concentrations ranging from 1.562 to 200 mg/ml were assessed for antifungal activity against F. oxysporum f. sp. lycopersici. There was 1 to 100% reduction in biomass of F. oxysporum f. sp. lycopersici due to these concentrations. GC-MS analysis of n-butanol fraction showed 25 compounds in it. Literature survey showed that among the identified compounds, 10 showed antifungal activities against different fungi. These antifungal compounds included 2-heptanol, 1-hexanol, 2-hexanol, 3-hexanol, 1- nonyne, decane, tridecane, palmitic acid, 3-octanone and β-sitosterol, could be responsible for antifungal activity against F. oxysporum f. sp. lycopersici in the present study. Bangladesh J. Bot. 51(4): 663-668, 2022 (December)

Macrophomina phaseolina is a highly problematic fungus that causes diseases in hundreds of plant species. In order to search for an alternative to chemical fungicides for the control of this devastating pathogen, leaf extract of Tabernaemontana divaricata was assessed for the control of M. phaseolina. Five concentrations of leaf extract in methanol viz. 1, 2, 3, 4 and 5% (w/v), were checked against M. phaseolina. All these concentrations significantly suppressed the fungal growth resulting in 34–74% decreased biomass of M. phaseolina over control. GC-MS analysis of this extract showed the presence of 54 compounds. Squalene was the predominant compound with 24.11% peak area followed by vitamin E (8.96%). Other important compounds were hexadecanoic acid, 2-hydroxy-1-(hydroxymethyl)ethyl ester (6.21%), thiophene, tetrahydro-2-methyl- (5.68%), cyclopentanol (5.61%), neophytadiene (6.25%), 1-tert-butoxypropan-2-yl 2-methylbutanoate (6.03%), ibogamine-18-carboxylic acid, 12-methoxy-, methyl ester (2.95%), phytol (2.26%), and n-hexadecanoic acid (2.20%). Some of these major compounds might be responsible for antifungal property of methanolic leaf extract of T. divaricata against M. phaseolina.

Ascochyta rabiei (Pass.) Lab. is a highly destructive pathogen of chickpea. In this study, leaf extract of Eucalyptus citriodora was assessed against this pathogen. Bioassays with methanolic extract (0, 05, 1.0, 1.5, …, 4.0%) extract revealed the remarkable antifungal potential of leaf extract where 69–94% reduction in biomass of A. rabiei was recorded. Chloroform fraction of this extract was separated by partitioning the extract in a separating funnel. Using a solvent system of chloroform: n-hexane (20:80), three compounds were detected on TLC plate which were separated through preparative TLC and purified on HPLC. GC-MS of the purified compounds lead to the identification of 3-cyclohexene- 1-ol, 4-methyl-1-(1-methylethyl)- (1), 1-cyclohexene- 1carboxaldehyde, 4-(1-methylethyl)- (2) and eucalyptol (3) that might caused antifungal activity of the extract.

The present study was carried out to evaluate the antagonistic efficacy of Aspergillus versicolor against the soil and seed inhibiting destructive plant pathogen Macrophomina phaseolina. The tested antagonist was confirmed by rDNA sequencing of ITS and β-tubulin genes with respective accession numbers MN719083 and MN736397. In dual culture bioassays, A. versicolor showed potent antagonist activity and reduced the pathogen’s growth by 60% over control. To understand the mechanism of antagonistic fungus, DNA of the pathogenic fungus was incubated in secondary metabolites produced by the A. versicolor for 24 and 48 h. After 48 h, metabolites of A. versicolor fully degraded the DNA of M. phaseolina. Moreover, for the identification of bioactive compounds, the chloroform and ethyl acetate fractions of A. versicolor culture filtrates were subjected to GC–MS analysis. A total of 10 compounds were identified in each of the two fractions. Among these, chondrillasterol (37.43%) followed by 1,2-benzedicarboxylic acid, diisooctyl ester (25.93%), decane (16.63%), 9,12-octadecadienoic acid (Z,Z)- (13.32%), stigmasterol (11.16%), undecane (10.93%), cis-1-chloro-9-octadecene (8.66%), benzene, 1,3,5-trimethyl (8.46%), and hexadecanoic acid, 2-hydroxy-1-(hydroxymethyl) ethyl ester (8.13%) were the major compounds. Some of the identified compounds are known to possess strong antifungal, antibacterial, nematicidal, and antioxidant properties. The present study concludes that A. versicolor is an effective antagonist against M. phaseolina.