Exploring morphological variability, in vitro antioxidant potential, and HR-LCMS phytochemical profiling of Phlomis cashmeriana Royle ex Benth. across different habitats of Kashmir Himalaya

Phytochemicals are broadly acknowledged for their health-promoting effects owing to the fact of their capacity to counteract free radicals (e.g., superoxide anion radical, hydroxyl radical, hydroperoxyl radical, singlet oxygen, hypochlorite, and nitric oxide) and shield against oxidative stress induced by environmental factors. This study aimed to investigate the relationship between altitude, morphology, soil parameters, in vitro antioxidant potential and phytochemical composition of Phlomis cashmeriana collected from four different locations of Kashmir Himalaya characterized by diverse habitats and elevations. Various factors, such as extraction method, solvent polarity, and habitat conditions, can impact the quantity and efficacy of phytochemicals in plants. The aim of current study was to analyze phytochemical composition and antioxidant activity of P. cashmeriana, an important medicinal plant found in the Kashmir Himalaya region. The antioxidant activity was accessed using several assays and the plant populations were selected based on their diverse habitat features and altitudes. HR-LCMS was conducted for both below-ground and above-ground parts. Some important compounds such as, catechin, vinainsenoside, acutilobin, and kaempferol were reported for the first time from P. cashmeriana. Results showed that methanol was the most efficient solvent for extracting phytochemicals. During the current study, it was also found that the below-ground parts exhibited superior antioxidant activity compared to the above-ground parts. Notably, Site IV demonstrated the highest antioxidant potential; a positive correlation between altitude and antioxidant activity was also found. In conclusion, present research identified specific elite populations having highest antioxidant potential and are well-suited for large-scale cultivation of P. cashmeriana.

Greener approach for the isolation of oleanolic acid from Nepeta leucophylla Benth. Its derivatization and their molecular docking as antibacterial and antiviral agents

In the present study bioactive methanolic extract along with chloroform and hexane extracts obtained from shade dried leaves of the Himalayan aromatic medicinal plant Nepeta leucophylla Benth. Were screened for the presence of triterpenoids, especially oleanolic acid (OA). Total three compounds oleanolic acid, squalene and linoleic methyl ester were isolated from methanol extract. The percentage yield of OA was 0.11%. Out of these three, OA is more bioactive and was further subjected to derivatization using greener Ultrasonication method. Total three derivatives (3-Acetyl oleanolic acid, 3-Phthaloyl oleanolic acid and 3-Oxo oleanolic acid) were synthesized with 91.16%, 93.98%, and 83.6% respectively. Further, the antioxidant potential of OA and its derivatives were evaluated using DPPH assay which suggested that the 3-Phthaloyl oleanolic acid exhibits highest antioxidant potential with 40.83 ± 1.14% inhibition. OA and its derivatives were screened in-silico antibacterial potential against three bacterial pathogens (E-coli, M. tuberculosis and S. aureus) and antiviral potential against Severe Acute Respiratory Syndrome Coronavirus (SARS-CoV-2), Human immunodeficiency virus (HIV) and H1N1 influenza virus. The in-silico results suggested that 3-phthaloyl oleanolic acid showed best H-bonding with FtsA (Staphylococcus aureus), enoyl acyl reductase (E. coli) and arabinosyl transferase (Mycobactrium tuberculosis). 3-Phthaloyl oleanolic acid also showed best H-Bond interactions with the target proteins hemagglutinin (H1N1) and reverse transcriptase (HIV), whereas, oleanolic acid exhibited the best interactions with RNA dependent RNA polymerase (SARS-CoV-2) and thus could be considered for further in vitro studies.

Novel schiff base as Fe3+ sensor as well as an antioxidant and its theoretical studies

A novel Schiff base derivative L (N1-(thiophene-2-ylmethylene)benzene-1,2-diamine) was synthesized via condensation reaction of 3-thiophene carboxaldehyde and 1,2-diamino benzene. The synthesized compound was authenticated using 1 H NMR, 13 C NMR, HRMS, and IR spectroscopy. The compound L was found to be a Fe3+ sensor with the complexation ratio of 1 : 3 as revealed by Job’s plot with maximum absorption at 318 nm. The photophysical properties were studied using absorption and emission spectra. DFT and TD-DFT studies were carried out in order to support the photophysical outcomes of compound L. An antioxidant behaviour of compound L was studied using TAC, FRAP, and DPPH assays and it was found to be showing better TAC activity than the used standard i.e. gallic acid.

The genus Nepeta: Traditional uses, phytochemicals and pharmacological properties

ETHNOPHARMACOLOGICAL RELEVANCE

Nepeta is a multiregional genus of the "Lamiaceae" (Labiatae or Mint) family. Species of Nepeta are a valuable part of traditional medicine and used extensively, particularly in the Himalayan region of India (Uttarakhand, Himachal Pradesh, Jammu and Kashmir, Leh-Ladakh), Pakistan (Khyber Pakhtunkhwaand Pakistani Kashmir), Nepal (Baglund district), also in China and hilly regions of Turkey and Iran. Nepeta species are extensively used as a remedy against a variety of ailments and conditions like chicken pox, tuberculosis, malaria, pneumonia, influenza, measles, stomach disorders, eye complaints, respiratory disorders, asthma, colds, coughs etc. AIM OF THE REVIEW: The main aim of this review is to present a comprehensive and detailed study on traditional uses, pharmacology, phytochemistry, toxicology of Nepeta species and suggest future direction on the design and conduct of various preparations, either alone or in blends with prevailing conventional remedies. The review also emphasizes encouraging researchers towards the wide range of pharmaceutical applications of the various species of Nepeta for their better use and exploration in the future.

MATERIAL AND METHODS

All the relevant data and information on different species of Nepeta were assembled using different databases, such as Science Direct, Springer, PubMed, Taylor and Francis imprints, Chemspider, Google scholar, review and research articles from peer-reviewed journals and unpublished data. Some select 'grey literature' sources viz. ethnobotanical books, chapters, Wikipedia and webpages were also studied.

RESULTS

A variety of bioactive secondary metabolites and nutraceuticals has been isolated from various species of Nepeta. These bioactive compounds belong to different classes of secondary metabolites, such as phenolic acids and their glycosides (rosmarinic acid, gallic acid, caffeic acid), flavonoids and their glycosides (cirsimaritin, salvigenin, luteolin, apigenin), iridoids (nepetalactones and their derivatives), terpenoids (1,8-cineole, linalool, β-caryophyllene, germacrene D, parnapimaro, β-amyrin, oleanolic acid, ursolic acid), steroids (β-sitosterol, stigmasterol), lignans, amino acids, carbohydrates, volatile oils, etc. The species of the genus Nepeta possess a variety of pharmacological activities namely anti-inflammatory, anti-nociceptive, anti-alzheimer, anticancer and cytotoxic, antioxidant, immunomodulatory, antimicrobial, antifungal, insecticidal and along with other biological activities.

CONCLUSION

The species of the genus Nepeta contains a rich source of various bioactive compounds, which are well tolerated as traditional medicines. In fact, different species of Nepeta are widely used in a variety of traditional medicinal systems all around the world. Owing to the variety of pharmacological properties of Nepeta species, more comprehensive and inclusive clinical trials are necessary for the utilization of different Nepeta species against the treatment of a wide range of ailments. There are also various other uses such as food, cosmetic and agriculture that can be investigated or explored in future. Some of the major domains that can be explored within this genus are the investigation of different species for their unexplored biological potential, isolation and characterization of new bioactive constituents and finally, investigation of new applications and possible commercialization of these bioactive leads. No doubt, there are various viable research domains outside those discussed above, but presently for the purposes of this review we will only emphasize the activities herein.

Diospyros kaki extract protects myoblasts from oxidative stress-induced cytotoxicity via secretions derived from intestinal epithelium

Under oxidative stress, reactive oxygen species (ROS) alter signal transduction and induce macromolecular damage in cells. Such oxidative damage can lead to sarcopenia, an age-related syndrome characterized by a progressive loss of mass and strength of skeletal muscles. Because food components do not directly come in contact with muscle cells, we focused on the effects of secretions produced by stimulated intestinal epithelial cells on oxidative stress in myoblast cells. An extract of Diospyros kaki was fractionated using different concentrations of ethanol. Each fraction showed different levels of antioxidant and phenolic compounds. The biological activity was evaluated using a Caco-2 cell coculture system. Secretions from Caco-2 cells exposed to 0.5 mg/mL D. kaki extract attenuated the oxidative stress-induced reduction of C2C12 cell viability, suggesting that the D. kaki extract could stimulate intestinal epithelial cells to produce secretions that reduce oxidative stress in myoblasts in vitro.

Plasmon-induced photocatalytic degradation of methylene blue dye using biosynthesized silver nanoparticles as photocatalyst

Bio-fabrication of silver nanoparticles, using stem extracts of Nepeta leucophylla and their photocatalytic degradation activity, has been undertaken. The synthesized silver nanoparticles are characterized using ultraviolet-visible spectroscopy, Fourier transformed infrared spectroscopy, X-ray diffractometry, Transmission Electron Microscopy, Field Emission Scanning Electron Microscopy, Energy-dispersive X-ray spectroscopy and thermal gravimetric and differential scanning calorimetry analysis. The Surface Plasmon Resonance band detected at 430 nm in the ultraviolet-visible spectrum confirms the formation of silver nanoparticles in the aqueous solution. Transmission Electron and Field Emission Scanning Electron micrographs reveal that the synthesized silver nanoparticles are spherical with an average size in the range of 15-25 nm. But, the X-ray diffraction confirms the face-centred cubic structure of silver nanoparticles with an average crystal size of the nanoparticles is about 10 nm. Furthermore, the infrared spectrogram confirms that the stem extract of Nepeta leucophylla contains phenol which causes reduction of silver salt to silver nanoparticles and protein might act as an overlaying agent which prevents the agglomeration of these nanoparticles. Moreover, the photocatalytic degradation of methylene blue dye, by using biosynthesized silver nanoparticles of optimized dose (1.8 ml) for 180 min in the presence and absence of light are 82.8% and 61.25%, respectively, specifies that the resultant photocatalyst is proved to have good photocatalytic activity for the degradation of methylene blue dye from the liquid phase.