Mahmoud Moustafa

This study investigates the nematicidal efficacy of Purpureocillium lilacinum strain (AUMC 10620) combined with avermectin (B1a and B1b) against the citrus nematode Tylenchulus semipenetrans, both in vitro and in vivo. Laboratory experiments tested four concentrations of P. lilacinum (2.5, 5, 10, and 15 × 10⁷ spores/mL) mixed with 250 ppm avermectin, assessing their effects on nematode juveniles (J2) and eggs. Results showed significant increases in juvenile mortality and egg hatching inhibition with the combined treatments compared to individual applications. The highest concentration (15 × 10⁷ spores/mL + 250 ppm avermectin) achieved 100% juvenile mortality and 83.33% egg hatching inhibition after 72 h. Field trials confirmed the superior efficacy of the combined treatment, with P. lilacinum (15 × 10⁷ spores/mL) and avermectin (1000 ppm) reducing nematode populations by 70.85% in mandarin trees and 70.77% in sweet orange trees after three weeks, compared to the 83.59% and 81.76% reduction, respectively, achieved by oxamyl. These findings suggest that mixtures of P. lilacinum and avermectin can serve as effective, eco-friendly alternatives for controlling nematodes in citrus orchards.

Anticandidal activities of stem extracts of C. gileadensis growing in various locations and chemicals had been evaluated. Methanol extract of fresh and dry solvent extracts in Tathleeth A region had the highest activity (2.2 ± 0.3cm) and (1.7 ± 0.2cm), respectively. Cyclohexanone of fresh stem extract and diethyl ether of dry extract showed inhibition activities (2.1 ± 0.1cm) of Tathleeth B. The highest activity gained from fresh hot water extract (1.4 ± 0.1 cm) and from dry extract of dichloromethane (1.7 ± 0.0 cm) in Tabala C. The maximum inhibiting activity obtained from hot water extract (1.8 ± 0.4 cm) and from chloroform of dry extract (2.0 ± 0.0cm) in Tabala D. GC-MS analysis showed that the dominant compound in Thathleeth A and Thathleeth B is Bisethylamine, Tabala C are 5-Methyl-2(5H)-furanone and palmatic acid and Tabala D is Amitrole. HPLC showed that Tabala D had the highest amount from B1 and folic acid. Thus, plant's biochemical parameters are profoundly influenced by their locations. Bangladesh J. Bot. 53(1): 1-8, 2024 (March)

This study investigated the effectiveness of nanoparticles and chemical inducers in managing onion white rot caused by Sclerotium cepivorum. The pathogen severely threatens onion cultivation, resulting in significant yield losses and economic setbacks. Traditional fungicides, though effective, raise environmental concerns, prompting a shift toward eco-friendly alternatives. In this study, four S. cepivorum isolates were utilized, each exhibiting varying degrees of pathogenicity, with the third isolate from Abu-Hamad demonstrating the highest potency. During the in vitro studies, three nanoparticles (NPs) were investigated, including Fe₃O₄ NPs, Cu NPs, and ZnO NPs, which demonstrated the potential to inhibit mycelial growth, with salicylic acid and Fe₃O₄ NPs exhibiting synergistic effects. In vivo, these nanoparticles reduced the disease incidence and severity, with Fe₃O₄ NPs at 1000–1400 ppm resulting in 65.0–80.0% incidence and 80.0–90.0% severity. ZnO NPs had the most positive impact on the chlorophyll content, while Cu NPs had minimal effects. At 1000 ppm, Fe₃O₄ NPs had variable effects on the phenolic compounds (total: 6.28, free: 4.81, related: 2.59), while ZnO NPs caused minor fluctuations (total: 3.60, free: 1.82, related: 1.73). For the chemical inducers, salicylic acid reduced the disease (10.0% incidence, 25.0% to 10.0% severity) and promoted growth, and it elevated the chlorophyll values and enhanced the phenolic compounds in infected onions. Potassium phosphate dibasic (PDP) had mixed effects, and ascorbic acid showed limited efficacy toward disease reduction. However, PDP at 1400 ppm and ascorbic acid at 1000 ppm elevated the chlorophyll values and enhanced the phenolic compounds. Furthermore, this study extended to traditional fungicides, highlighting their inhibitory effects on S. cepivorum. This research provides a comprehensive comparative analysis of these approaches, emphasizing their potential in eco-friendly onion white rot management.

Avian pathogenic Escherichia coli (APEC) induces colibacillosis, an acute and systemic disease, resulting in substantial economic losses in the poultry sector. This study aimed to investigate the antibiotic resistance pattern associated with frequent virulence gene distribution in APEC O78:K80 that may cause pathological alterations in chickens. The antibiogram profile showed high resistance to erythromycin, chloramphenicol, tetracycline, ampicillin, and co-trimoxazole, followed by intermediate resistance to ciprofloxacin, levofloxacin, enrofloxacin, norfloxacin, nitrofurantoin, and doxycycline hydrochloride, and sensitive to amikacin, streptomycin, gentamicin, and colistin. Virulence gene distribution identifies eight (irp-2, iutA, ompT, iss, iucD, astA, hlyF, iroN) genes through a conventional polymerase chain reaction. APEC O78:K80 caused significantly high liver enzyme concentrations, serum interleukin-6 and tumor necrosis factor-alpha levels in experimental birds. Also, infected birds have hypoproteinemia, hypoalbuminemia, and hyperglobulinemia. Necropsy examination revealed fibrinous perihepatitis and pericarditis, congested lungs, intestinal ecchymotic hemorrhages and necrotizing granulomatosis of the spleen. Histopathological examination depicted hepatocellular degeneration, myocardial necrosis, interstitial nephritis, intestinal hemorrhages and lymphopenia in the spleen. This study is the first evidence to assess the antibiotic resistance profile linked with virulence genes and clinicopathological potential of APEC O78:K80 in chickens in Pakistan, which could be a useful and rapid approach to prevent and control the disease by developing the control strategies.

Climate-change-induced variations in temperature and rainfall patterns are a serious threat across the globe. Flooding is the foremost challenge to agricultural productivity, and it is believed to become more intense under a changing climate. Flooding is a serious form of stress that significantly reduces crop yields, and future climatic anomalies are predicted to make the problem even worse in many areas of the world. To cope with the prevailing flooding stress, plants have developed different morphological and anatomical adaptations in their roots, aerenchyma cells, and leaves. Therefore, researchers are paying more attention to identifying developed and adopted molecular-based plant mechanisms with the objective of obtaining flooding-resistant cultivars. In this review, we discuss the various physiological, anatomical, and morphological adaptations (aerenchyma cells, ROL barriers (redial O₂ loss), and adventitious roots) and the phytohormonal regulation in plants under flooding stress. This review comprises ongoing innovations and strategies to mitigate flooding stress, and it also provides new insights into how this knowledge can be used to improve productivity in the scenario of a rapidly changing climate and increasing flood intensity.

Drang Drung and Pensilungpa are neighbouring glaciers in the western Himalayas, sharing the same meteorological conditions and climate zone. The Drang Drung glacier is a clean glacier, whereas the Pensilungpa glacier is notable for its considerable accumulation of debris. The present study explores the topographical features of the Drang Drung and Pensilungpa glaciers and investigates how topography affects their response to climate change. Additionally, a comparison is made between these glaciers with others in the basin to assess their representativeness of the region. The study utilized Landsat Imagery and ASTER GDEM data from 1976 to 2020. The results revealed that the mean accumulation area ratio (AAR) for Drang Drung and Pensilungpa was 54% and 49%, respectively, during this period. Drang Drung has lost 8.16 km² (10.73%) of its area, while Pensilungpa has lost 2.25 km² (9.84%) of its area. The debris cover of Pensilungpa increased from 1.86 km² in 1976 to 2.32 km² in 2020, whereas the debris cover area of Drang Drung has increased comparatively more, from 4.01 km² to 4.76 km². Within the same time frame, the snowline altitude (SLA) shifted upward by an average of 104 m and 88 m for Drang Drung Pensilungpa, respectively. Further, our findings revealed a substantial connection between the size of glaciers and the speed at which their area is diminishing. The mean slope was identified as a key factor in influencing the rate at which the area is lost, and the retreat rates of the glaciers. The reduction in glacial area, increased debris coverage, and changes in SLA are key indicators of ice volume loss under prevailing climatic conditions. The present study recommends that long-term field-based data and the incorporation of multi-temporal satellite imagery are crucial to mitigate uncertainties in detecting changes in Himalayan glaciers. These approaches would contribute to a more accurate understanding of glacial changes, and would aid in forecasting future scenarios considering ongoing global warming trends.

Nicotiana glauca was recorded as one of the invasive plant species which is dramatically spreading in many countries. Extracts of methanol, hexane, acetone, ethanol and petroleum ether of leaves of Nicotiana glauca obtained from seven locations were screened for their antimicrobial activities against Klebsiella oxytoca, Shigella sp., Staphylococcus aureus, Micrococcus luteus and Candida albicans. Forty seven chemical compounds were characterized and vitamins B1, B12, B2 and folic acid were also found. All studied locations had toxic chemicals to human namely anabasine. The similarity index among locations was about 69.01% and the most dominant compound were 2-Pentanone, 4-hydroxy-4-methyl, 1,3-Dioxolane- 2-methanol, 2,4-dimethyl and 2-Acetoxyisobutyryl chloride. Interestingly, the plant had anabasine and showed low antimicrobial effect against specific human pathogens. Data of permanent quadrats showed the plant spread in a progressive manner. Bangladesh J. Bot. 52(2): 403-410, 2023 (June)

The majority of the world population (around 25%) has latent Mycobacterium tuberculosis (Mtb) infection, among which only 5–10% of individuals develop active tuberculosis (TB), and 90–95% continue to have latent tuberculosis infection. This makes it the biggest global health concern. It has been reported that the resuscitation-promoting factor B (RpfB) is an exciting potential target for tuberculosis drug discovery due to its significant role in the reactivation of latent TB infection to an active infection. Several attempts have been made to investigate potential inhibitors against RpfB utilizing in-silico approaches. The present study also utilized a computational approach to investigate microbially derived natural compounds against the Mtb RpfB protein which is a very cost-effective This evaluation used structure-based virtual screening (SBVS), drug-likeness profiling, molecular docking, molecular dynamics simulation, and free-binding energy calculations. Six potential natural compounds, viz. Cyclizidine I, Boremexin C, Xenocoumacin 2, PM-94128, Cutinostatin B, and (+)1-O-demethylvariecolorquinone A were selected, which displayed a potential binding affinity between −52.39 and −60.87 Kcal/mol MMGBSA score and docking energy between −7.307 Kcal/mol to −6.972 Kcal/mol. All the complexes showed acceptable stability (<2.7 Å RMSD) during 100 ns MD simulation time except the RpfB protein-xenocoumacin 2 complex. This result exhibited that the selected compounds have high efficiency in inhibiting the Mtb RpfB and can be taken into account for additional in vitro and in vivo experimental validation. Communicated by Ramaswamy H. Sarma

The failure of chemotherapy in the treatment of carcinoma is mainly due to the development of multidrug resistance (MDR), which is largely caused by the overexpression of P-glycoprotein (P-gp/ABCB1/MDR1). Until recently, the 3D structure of the P-gp transporter has not been experimentally resolved, which restricted the discovery of prospective P-gp inhibitors utilizing in silico techniques. In this study, the binding energies of 512 drug candidates in clinical or investigational stages were assessed as potential P-gp inhibitors employing in silico methods. On the basis of the available experimental data, the performance of the AutoDock4.2.6 software to predict the drug-P-gp binding mode was initially validated. Molecular docking and molecular dynamics (MD) simulations combined with molecular mechanics-generalized Born surface area (MM-GBSA) binding energy computations were subsequently conducted to screen the investigated drug candidates. Based on the current results, five promising drug candidates, namely valspodar, dactinomycin, elbasvir, temsirolimus, and sirolimus, showed promising binding energies against P-gp transporter with ΔG_binding values of −126.7, −112.1, −111.9, −102.9, and −101.4 kcal/mol, respectively. The post-MD analyses revealed the energetical and structural stabilities of the identified drug candidates in complex with the P-gp transporter. Furthermore, in order to mimic the physiological conditions, the potent drugs complexed with the P-gp were subjected to 100 ns MD simulations in an explicit membrane-water environment. The pharmacokinetic properties of the identified drugs were predicted and demonstrated good ADMET characteristics. Overall, these results indicated that valspodar, dactinomycin, elbasvir, temsirolimus, and sirolimus hold promise as prospective P-gp inhibitors and warrant further invitro/invivo investigations. Graphical abstract Communicated by Ramaswamy H. Sarma