In this study, a stepwise reaction afforded thiazolidinone-based benzothiazole derivatives 1–15, and the synthesized derivatives were then screened for biological significance and found to be the leading candidates against α-amylase and α-glucosidase enzymes. Almost all derivatives showed excellent to good activity ranging against α-amylase, IC50 = 2.10 ± 0.70 to 37.50 ± 0.70 μM, and α-glucosidase, IC50 = 3.20 ± 0.05 to 39.40 ± 0.80 μM. Some analogues such as 4 (2.40 ± 0.70 and 3.50 ± 0.70 μM), 5 (2.30 ± 0.05 and 4.80 ± 0.10 μM), and 6 (2.10 ± 0.70 and 3.20 ± 0.70 μM) were found with folds better activity than that of the standard drug acarbose (9.10 ± 0.10 and 10.70 ± 0.10 μM), respectively. Moreover, the structure–activity relationship (SAR) has been established for all compounds. A molecular docking study has been carried out to explore the binding interactions against α-amylase and α-glucosidase enzymes.

The current study evaluates the protective effects of Thymoquinone (Tq) and Curcumin (Cur) in models of cisplatin-induced renal toxicity. Proliferation studies were carried out in HEK-293 cells. Cisplatin(ip) 5 mg/kg BW was used to induce renal injury in Sprague Dawley rats. 50 mg/kg BW Tq +100 mg/kg BW Cur, with or without cisplatin-treatment were administered for 5 days. Tq + Cur combination synergistically reduced the proliferation inhibition of HEK-293 cells resulted from cisplatin treatment and brought down cisplatin-induced apoptosis in these cells. In vitro studies revealed serum levels of BUN, creatinine, CK and pro-inflammatory cytokines like TNF-α, IL-6, and MRP-1 to be elevated in the cisplatin-treated group while reducing glomerular filtration rate. Tq + Cur treatment significantly improved these conditions. The antioxidant enzyme levels and mitochondrial ATPases were restored upon treatment, which were lessened in the cisplatin-treated group. Cisplatin induced the expression of KIM-1, which was brought down by the combination treatment. Tq + Cur treatment increased the expressions of phosphorylated Akt, Nrf2 and HO-1 proteins while decreasing the levels of cleaved caspase 3 and NFƙB in kidney homogenates. In summary, Tq + Cur had protective effects on cisplatin-induced nephrotoxicity and renal injury, which could be mediated by up-regulation of survival signals like Akt, Nrf2/HO-1, and attenuation of KIM-1, NFƙB.

In this study, hybrid analogs of benzimidazole containing a thiazole moiety (1–17) were afforded and then tested for their ability to inhibit α-amylase and α-glucosidase when compared to acarbose as a standard drug. The recently available analogs showed a wide variety of inhibitory potentials that ranged between 1.31 ± 0.05 and 38.60 ± 0.70 µM (against α-amylase) and between 2.71 ± 0.10 and 42.31 ± 0.70 µM (against α-glucosidase) under the positive control of acarbose (IC₅₀ = 10.30 ± 0.20 µM against α-amylase) (IC₅₀ = 9.80 ± 0.20 µM against α-glucosidase). A structure–activity relationship (SAR) study was carried out for all analogs based on substitution patterns around both rings B and C respectively. It was concluded from the SAR study that analogs bearing either substituent(s) of smaller size (−F and Cl) or substituent(s) capable of forming hydrogen bonding (−OH) with the catalytic residues of targeted enzymes enhanced the inhibitory potentials. Therefore, analogs 2 (bearing meta-fluoro substitution), 3 (having para-fluoro substitution) and 4 (with ortho-fluoro group) showed enhanced potency when evaluated against standard acarbose drug with IC₅₀ values of 4.10 ± 0.10, 1.30 ± 0.05 and 1.90 ± 0.10 (against α-amylase) and 5.60 ± 0.10, 2.70 ± 0.10 and 2.90 ± 0.10 µM (against α-glucosidase), correspondingly. On the other hand, analogs bearing substituent(s) of either a bulky nature (−Br) or that are incapable of forming hydrogen bonds (−CH₃) were found to lower the inhibitory potentials. In order to investigate the binding sites for synthetic analogs and how they interact with the active areas of both targeted enzymes, molecular docking studies were also conducted on the potent analogs. The results showed that these analogs adopted many important interactions with the active areas of enzymes. The precise structure of the newly synthesized compounds was confirmed using several spectroscopic techniques as NMR and HREI-MS.

The current study was conducted to obtain hybrid analogues of indole-based thiadiazole derivatives (1–16) in which a number of reaction steps were involved. To examine their biological activity in the presence of the reference drug Donepezil (0.21 ± 0.12 and 0.30 ± 0.32 M, respectively), the inhibitory potentials of AChE and BuChE were determined for these compounds. Different substituted derivatives showing a varied range of inhibitory profiles, when compared to the reference drug, analogue 8 was shown to have potent activity, with IC50 values for AchE 0.15 ± 0.050 M and BuChE 0.20 ± 0.10, respectively, while other substituted compounds displayed good to moderate potentials. Varied spectroscopic techniques including ¹H, ¹³CNMR and HREI-MS were used to identify the basic skeleton of these compounds. Furthermore, all analogues have a known structure–activity relationship (SAR), and molecular docking investigations have verified the binding interactions of molecule to the active site of enzymes.

Objectives: To explore the antibacterial activity of thymoquinone (TQ), a quinone extracted from Nigella sativa. Methods: This study was conducted from May 2019 to March 2020 at the Department of Clinical Laboratory Sciences, College of Applied Medical Sciences, King Khalid University, Abha, Saudi Arabia. The antimicrobial activity, minimum inhibitory concentration (MIC), and minimum bactericidal concentration (MBC) of TQ were determined using an agar well diffusion method and broth microdilution assays, and the synergistic effect was evaluated using antibiotics in parallel. The disruptive effect of TQ on bacterial cell membranes was determined using scanning electron microscopy. The antivirulence properties of TQ, which include adherence and biofilm formation, were also investigated using adherence and biofilm formation assays, respectively. Results: Thymoquinone demonstrated bactericidal efficacy against 4/14 bacterial strains, with MIC range of 1.04-8.3 µg/mL and and MBC range of 10.41–66.66 µg/mL. Thymoquinone showed synergism against Klebsiella pneumoniae, Staphylococcus epidermidis (American Type Culture Collection 12228), Staphylococcus aureus, and Staphylococcus epidermidis in combination with the tested antibiotics. Thymoquinone inhibited bacterial adhesion by 39%-54%, 48%-68%, and 61%-81% at 0.5 × MIC, 1 × MIC, and 2 × MIC, respectively. The tested bacterial strains significantly inhibited biofilm formation after treatment with various concentrations of TQ for 24 and 48 hours. Conclusion: The combinatory effect of TQ with antimicrobials should be considered when developing new antimicrobial therapy regimens to overcome multidrug-resistant.

Solanum nigrum is a traditional medicinal plant renowned as a cure for many diseases due to the presence of bioactive compounds. The Solanum nigrum complex refers to a group of more than 30 closely related but morphologically distinct taxa. Five indigenous taxa of this complex were investigated for their medicinal potential by using methanolic extracts. The efficacy of each plant was different for each of the seven bacteria studied. On comparing the MIC values, S. americanum was found to be most potent against Bacillus licheniformis (34 µg/mL), S. chenopodioides against Escherichia coli (78 µg/mL), S. nigrum against Bacillus licheniformis (49 µg/mL) and Escherichia coli (49 µg/mL), S. retroflexum against Escherichia coli (30 µg/mL), and S. villosum against Proteus mirabilis (45 µg/mL). The extracts were also subjected to six antioxidant assays. Moderate scavenging activity was observed by all plants in the DPPH free radical assay, but S. chenopodioides was the most effective. The total phenolic contents of the five plants were comparable, but the gallic acid equivalents of S. americanum and S. nigrum were the highest (26.58 mg/100 g GAE). The highest Trolox equivalent antioxidant capacity was observed for S. retroflexum, with the ABTS assay giving a TEAC value of 33.88 mM/100 g of dry weight. Metal-chelating activity against Fe²⁺ was observed to be highest for S. chenopodioides (70.37%). The FRAP value of S. nigrum was the highest (8.5 mM FeSO₄·7H₂O) among all taxa. The lipid peroxidation trend was very similar for all five samples. The results suggest the specified medicinal use of different members of the Solanum nigrum complex, which will also have significant nutritional value.