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271.
Zahid Mahmood Sarwar Muhammad Sajjad Muhammad Farhan Malik Najam-ul-Hassan Muhammad Faisal Shahzad Muhammad Binyameen Intazar Ali Junaid Rahim Mohamed Hashem Saad Alamri Haseeb ur Rehman 《Saudi Journal of Biological Sciences》2021,28(10):5720-5727
Taxonomic identification and classifications of insect pest genera Chrysodeixis and Ctenoplusia of the subfamily Plusiinae is very compulsory due to their phytophagous nature and potential to damage the cash as well as cereal crops. Taxonomy plays a key role in proper not only in identification and classification of the pest but also in designing a successful managing strategy. In current study, specimens of Chrysodeixis and Ctenoplusia genera were collected from different geographical areas of south Punjab, Pakistan and their diagnostic features were examined following taxanomic keys. The data of temperature, relative humidity and rainfall were also recorded during the study period. Genitalia was extracted by dissecting of the abdomen and inspected under Stereo microscope. The results revealed two new species, Chryodeixis maxus and Ctenoplusia oleraceaus, from south Punjab region in addition to previously reported species: Chrysodeixis furihatai. Suitable management of the voracious insect pest at appropriate time may help in sustaining the agriculture in Pakistan. 相似文献
272.
Tayyiba Afzal Yamin Bibi Muhammad Ishaque Saadia Masood Abdul Qayyum Sobia Nisa Zahid Hussain Shah Hameed Alsamadany Gyuhwa Chung 《Saudi Journal of Biological Sciences》2022,29(2):1185
Medicinal plants have significant contribution in pharmaceutical industries being producers of compounds utilized as precursors for drug development. A plant of Lamiaceae family; Pseudocaryopteris foetida had not been investigated for its biomedical potential. Current research was aimed to investigate phytochemical analysis, cytotoxic potential and antioxidant activity of crude methanolic extract and fractions of Pseudocaryopteris foetida (leaves). The preliminary phytochemical analysis of crude methanolic extracts and fractions of Pseudocaryopteris foetida revealed that plant is rich in phenolic and flavonoid classes of secondary metabolites while presence of tannin was observed only in crude methanolic extract. The cytotoxicity was determined using brine shrimp lethality test. Different concentrations (25, 50, 100, 150, 200 and 250 µg/mL) of crude methanolic extract and fractions exhibited dose dependent cytotoxicity. However, The LD50 for all the extracts was more than 200 µg/mL indicating weak cytotoxic potential of Pseudocaryopteris foetida. The antioxidant capabilities of crude methanolic extract and fraction of Pseudocaryopteris foetida were analyzed by in vitro bio assays including DPPH, ABTS, Reducing power and phosphomolybdate antioxidant assays using ascorbic acid as standard. The crude methanolic extract showed IC50 (256.38 ± 0.6 and 314.95 ± 1.1 µg/mL) for DPPH and ABTS respectively, while total antioxidant capacity was calculated as 55.79 ± 0.5 µg/mL for crude methanolic extract of Pseudocaryopteris foetida while ascorbic acid indicated total antioxidant capacity of 71.89 ± 2.3 µg/mL. Study concluded that leaves of Pseudocaryopteris foetida were the rich source of antioxidant phytochemicals. Based on preliminary investigations further research should be focused to isolate bioactive phytochemicals as leading source of clinical medicines in future. 相似文献
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Zahid H. Chohan Abdul Rauf Muhammad M. Naseer Muhammad A. Somra Claudiu T. Supuran 《Journal of enzyme inhibition and medicinal chemistry》2013,28(2):173-177
A series of antibacterial and antifungal sulfonamide (sulfanilamide, sulfaguanidine, sulfamethaxozole, 4-aminoethylbenzenesulfonamide and 4-amino-6-trifluoromethyl-benzene-1,3-disulfonamide) derived chromones, previously reported as inhibitors of carbonic anhydrase, have been screened for in-vitro antibacterial activity against four Gram-negative (Escherichia coli, Pseudomonas aeruginosa, Salmonella typhi and Shigella flexeneri) and two Gram-positive (Bacillus subtilis and Staphylococcus aureus) bacterial strains, and for in-vitro antifungal activity against Trichophyton longifusus, Candida albicans, Aspergillus flavus, Microsporum canis, Fusarium solani, Candida glaberata. All compounds (1)–(5) showed significant antibacterial activity against all four Gram-negative species and both Gram-positive species. However, three of them, (1), (4) and (5), were found to be comparatively much more active compared to (2) and (3). Of these, (5) was found to be the most active one. For antifungal activity, generally compounds (1) and (2) showed significant activity against more than three strains whereas (3)–(5) also showed significant activity against varied fungal strains. In the brine shrimp bioassay for in-vitro cytotoxic properties, only two compounds, (4) and (5) displayed potent cytotoxic activity, LD50 = 2.732 × 10? 4 M) and LD50 = 2.290 × 10? 4 M) respectively, against Artemia salina. 相似文献
275.
Humayun Pervez Zahid Hussain Chohan Muhammad Ramzan Faiz-Ul-Hassan Nasim Khalid Mohammed Khan 《Journal of enzyme inhibition and medicinal chemistry》2013,28(2):437-446
A new series of 12 N4-substituted isatin-3-thiosemicarbazones 2a-l has been synthesized, characterized and screened for in vitro cytotoxic, phytotoxic and urease inhibitory effects. All the compounds proved to be active in the brine shrimp bioassay; 2a, 2b, 2d, 2f and 2h-l exhibited a high degree of cytotoxic activity (LD50 = 1.10 × 10? 5 M–3.10 × 10? 5 M). In urease-inhibition assay, compounds 2a, 2b, 2e, 2f, 2h-j and 2l proved to be potent inhibitors displaying relatively much greater inhibition of the enzyme with IC50 values ranging from 20.6 μM to 50.6 μM. Amongst these, 2a and 2f were found to be the most potent ones exhibiting pronounced inhibition with IC50 value 20.6 μM. All the synthetic compounds showed weak to moderate (10–40%) phytotoxicity at the highest tested concentration (500 μg/mL) indicating their usefulness as inhibitors of soil ureases. 相似文献
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