Antimicrobial activities of methanolic extract of Carissa opaca roots and its fractions and compounds isolated from the most active ethyl acetate fraction

Evaluation of Biogenic Silver Nanoparticles Synthesized from Vegetable Waste

Introduction

Vegetable waste has numerous essential values and can be used for various purposes. Unfortunately, it is often discarded worldwide due to a lack of awareness regarding its nutritional and practical significance. Even the nutrient-rich peels of fruits and vegetables are commonly wasted, despite their numerous useful applications. Utilizing vegetable waste to produce silver nanoparticles through green synthesis is an advantageous, economical, and environmentally friendly method for producing valuable products while addressing waste management concerns. The main emphasis of this study was to synthesize silver nanoparticles (AgNPs) by using vegetable waste from Solanum tuberosum (potato) and Coriander sativum (coriander).

Methods

The stems of Coriander sativum and peels of Solanum tuberosum were used as extracts for the synthesis of AgNPs. The characterization of the synthesized AgNPs involved UV-spectroscopy, scanning electron microscopy (SEM), and X-ray diffraction (XRD). The phytochemical analysis was performed to analyze antimicrobial, cytotoxic, antidiabetic, antitumor, antioxidant, alpha-amylase, and protein inhibition activities.

Results

The change in the color of the reaction mixture from yellowish green to brown following the addition of extracts to the silver nitrate solution confirmed nanoparticle synthesis. UV analysis has shown peaks in the range of 300-400nm. SEM confirmed the spherical and agglomerated morphology and size of 64nm for potato peel and 70nm for coriander stem. XRD confirmed the crystalline structure of silver nanoparticles. The phytochemical assays confirmed that silver nanoparticles had higher total phenolic and flavonoid contents. The biosynthesized silver nanoparticles showed promising antimicrobial, cytotoxic, antidiabetic, antitumor, and antioxidant properties and significant alpha-amylase and protein inhibition activities in comparison with the crude extracts.

Conclusion

The bioactivity of the plant suggests that it could be a suitable option for therapeutic purposes. This study demonstrates a potential method for sustainable nanoparticle synthesis and the therapeutic applications of AgNPs derived from vegetable waste. By utilizing the potential of vegetable waste, we can contribute to both environmental sustainability and the development of innovative, valuable products in fields such as medicine, agriculture, and materials science. These findings encourage further research on agricultural byproducts, promoting environmentally friendly and economically advantageous research and development efforts.

GC Analysis, Anticancer, and Antibacterial Activities of Secondary Bioactive Compounds from Endosymbiotic Bacteria of Pomegranate Aphid and Its Predator and Protector

Bacterial secondary metabolites are a valuable source of various molecules that have antibacterial and anticancer activity. In this study, ten endosymbiotic bacteria of aphids, aphid predators and ants were isolated. Bacterial strains were identified according to the 16S rRNA gene. Ethyl acetate fractions of methanol extract (EA-ME) were prepared from each isolated bacterium and tested for their antibacterial activities using the disk diffusion method. The EA-ME of three bacterial species, Planococcus sp., Klebsiella aerogenes, Enterococcus avium, from the pomegranate aphids Aphis punicae, Chrysoperia carnea, and Tapinoma magnum, respectively, exhibited elevated antibacterial activity against one or several of the five pathogenic bacteria tested. The inhibition zones ranged from 10.00 ± 0.13 to 20.00 ± 1.11 mm, with minimum inhibitory concentration (MIC) values ranging from 0.156 mg/mL to 1.25 mg/mL. The most notable antibacterial activity was found in the EA-ME of K. aerogenes against Klebsiella pneumonia and Escherichia coli, with an MIC value of 0.156 mg/mL. The cytotoxic activity of EA-ME was dependent on the cell line tested. The most significant cytotoxicity effect was observed for extracts of K. aerogenes and E. avium, at 12.5 µg/mL, against the epithelial cells of lung carcinoma (A549), with a cell reduction of 79.4% and 67.2%, respectively. For the EA-ME of K. aerogenes and Pantoea agglomerans at 12.5 µg/mL, 69.4% and 67.8% cell reduction were observed against human colon cancer (Hct116), respectively. Gas chromatography-mass spectrometry (GC-MS) analysis of three EA-ME revealed the presence of several bioactive secondary metabolites that have been reported previously to possess antibacterial and anticancer properties. To the best of our knowledge, this is the first study to examine the biological activities of endosymbiotic bacteria in aphids, aphid predators and ants. The promising data presented in this study may pave the way for alternative drugs to overcome the continued emergence of multidrug-resistant bacteria, and find alternative drugs to conventional cancer therapies.

Comparative evaluation of biomedical and phytochemical applications of zinc nanoparticles by using Fagonia cretica extracts

The use of the green approach for nanoparticle synthesis yielded noticeable concern due to its eco-friendliness, cost-effectiveness, and reduced production of toxic chemicals. The current study was designed to formulate Zinc oxide nanoparticles (ZnO NPs) by using Fagonia cretica extracts, evaluating its phytochemical content, and different biological activities. Four different solvents; methanol (MeOH), n-Hexane (n–H), aqueous (Aq), and ethyl acetate (EA), had been utilized in the extracting method. ZnO NPs were successfully synthesized and characterized by UV–vis spectroscopy and scanning electron microscopy (SEM). The UV–vis spectra showed absorbance peaks between 350–400 nm range and SEM analysis revealed spherical morphology with particle sizes ranging from 65–80 nm. In phytochemical analysis, crude extracts exhibited the highest phytochemical content as they contain enriched secondary metabolites. n-hexane extract showed the highest phenolic contents while aqueous extracts showed the highest flavonoid content. Maximum free radicle scavenging activity was observed in NPs synthesized from ethyl-acetate extract with an IC₅₀ value of 35.10 µg/ml. Significant antibacterial activity was exhibited by NPs polar solvents against K. pneumonae, E. coli, and B. subtilis. Polar solvents showed considerable antifungal potential against A. flavus and F. solani. NPs synthesized from nH extract showed potential cytotoxic activity with an LC₅₀ value of 42.41 µg/ml against brine shrimps. A noteworthy antidiabetic activity was exhibited by nanoparticles synthesized from methanol extract i.e., 52.61 ± 0.36%. Significant bald zones were observed in nanoparticles synthesized from methanol extract rendering protein kinase inhibition. The present study highlights the significance of F. indica as a natural source for synthesizing functional nanoparticles with substantial antioxidant, antimicrobial, cytotoxic, protein kinase inhibitory, and antidiabetic properties.

Comparative Evaluation of Biomedical Applications of Zinc Nanoparticles Synthesized by Using Withania somnifera Plant Extracts

Green synthesis of metal nanoparticles is of great importance in the modern health care system. In this study, zinc nanoparticles (ZnONPs) were synthesized using leaf and root extracts of Withania somnifera using four different solvents. ZnONPs were characterized by UV-vis spectrophotometer with a range between 350–400 nm. Scanning electron microscope revealed spherical morphology with an overall size of 70–90 nm and XRD pattern confirmed the crystalline structure. The total flavonoids, phenolic, and alkaloid contents were significantly greater in the crude extracts as compared to ZnONPs. The highest scavenging activity was observed in ZnONPs from n-hexane and ethyl-acetate extracts of roots with IC₅₀ values of 27.36 µg/mL and 39.44 µg/mL, respectively. ZnONPs from methanol and aqueous extracts showed significant antibacterial activity against Escherichia coli, Staphylococcus aureus, and Bacillus subtilis while none of the extracts were found to have significant antifungal activity. Maximum cytotoxic activity was observed in ZnONPs synthesized from aqueous and n-hexane root extracts with LC₅₀ values of 9.36 µg/mL and 18.84 µg/mL, respectively. The highest antidiabetic potential was exhibited by ZnONPs from n-hexane leaf extracts, i.e., 47.67 ± 0.25%. Maximum protein kinase inhibitory potential was observed in ZnONPs of ethyl-acetate extract of roots with a bald zone of 12 mm. These results indicated that Withania somnifera-based ZnONPs showed significant biological activities compared to crude extracts. These findings can further be utilized for in-vivo analysis of nano-directed drug delivery systems.

Phytochemistry, Pharmacology, and Nutraceutical Profile of Carissa Species: An Updated Review

Carissa, a genus of the Apocynaceae family, consists of evergreen species, such as shrubs as well as small trees that are native to Asia, Africa, and Oceania’s subtropical and tropical regions. Most of the Carissa species are traditionally used to treat various diseases, such as chest pain, headaches, gonorrhoea, rheumatism, syphilis, oedema, rabies, stomach pain, hepatitis, cardiac diseases, and asthma. The pharmacological studies on Carissa species revealed its antioxidant, antimicrobial, anticancer, cardioprotective, antipyretic, analgesic, wound healing, anticonvulsant, antiarthritic, adaptogenic, anti-inflammatory, and antidiabetic activities, thus validating its use in indigenous medicine systems. The review article summarised the comprehensive literature available, including morphology, indigenous uses, bioactive composition, nutraceutical, and pharmacological activities of Carissa species. A total of 155 research papers were cited in this review article. The Carissa fruits are rich in dietary fibre, lipids, proteins, carbohydrates, vitamin C, and macro- and micro-elements. A total of 121 compounds (35 polyphenols (flavonoids and phenolic acids), 30 lignans, 41 terpenoids, 7 steroids, 2 coumarins, and 6 cardiac glycosides) have been extracted from C. spinarum, C. carandas, and C. macrocarpa. Among all chemical constituents, lupeol, carissol, naringin, carisssone, scopoletin, carissaeduloside A, D, J, carandinol, sarhamnoloside, carissanol, olivil, carinol, 3β-hydroxyolean-11-en-28,13β-oilde, ursolic acid, and carissone are the key bioactive constituents responsible for pharmacological activities of genus Carissa. The gathered ethnopharmacological information in the review will help to understand the therapeutic relevance of Carissa as well as paving a way for further exploration in the discovery of novel plant-based drugs.

Herbal Extracts with Antifungal Activity against Candida albicans: A Systematic Review

In the era of antimicrobial resistance, fungal pathogens are not an exception. Several strategies, including antimicrobial stewardship programs and high throughput screening of new drugs, are being implemented. Several recent studies have demonstrated the effectiveness of plant compounds with antifungal activity. In this systematic review, we examine the use of natural compounds as a possible avenue to fight fungal infections produced by Candida albicans, the most common human fungal pathogen. Electronic literature searches were conducted through PubMed/MEDLINE, Cochrane, and Science Direct limited to the 5 years. A total of 131 articles were included, with 186 plants extracts evaluated. Although the majority of the natural extracts exhibited antifungal activities against C. albicans (both in vivo and in vitro), the strongest antifungal activity was obtained from Lawsonia inermis, Pelargonium graveolens, Camellia sinensis, Mentha piperita, and Citrus latifolia. The main components with proven antifungal activities were phenolic compounds such as gallic acid, thymol, and flavonoids (especially catechin), polyphenols such as tannins, terpenoids and saponins. The incorporation of nanotechnology greatly enhances the antifungal properties of these natural compounds. Further research is needed to fully characterize the composition of all herbal extracts with antifungal activity as well as the mechanisms of action of the active compounds.

Effect of Caralluma tuberculata on regulation of carbohydrate metabolizing genes in alloxan-induced rats

ETHNOPHARMACOLOGICAL RELEVANCE

Caralluma tuberculata (C. tuberculata) has traditionally been used in Pakistan and other parts of the world as a folk treatment for diabetes mellitus. A few studies indicated its antihyperglycemic effect, however, the mystery remained unfolded as how did it modify the pathophysiological condition.

AIM OF STUDY

Hence, this study aimed to explore underlying mechanism(s) for its hypoglycemic activity at biochemical and molecular levels.

MATERIALS AND METHODS

Methanol extract (ME) of C. tuberculata as well as its hexane (HF) and aqueous (AF) fractions were explored for their effect on total glycogen in liver and skeletal muscle of alloxan-induced rats by spectroscopy. Moreover, the expression of genes related to hepatic carbohydrate metabolizing enzymes was quantified. At molecular level, mRNA expression of glucose transporter 2 (GLUT-2), glycogen synthase (GS), glucokinase (GK), hexokinase 1 (HK-1), pyruvate kinase (PK), glucose 6 phosphate dehydrogenase (G-6-PDH), pyruvate carboxylase (PC), phosphoenolpyruvate carboxykinase (PEPCK) and glucose 6 phosphatase (G-6-Pase) was determined by using quantitative real time polymerase chain reaction (qRT-PCR) after administration of ME (350 mg), HF(3 mg), AF (10 mg) and metformin (500 mg). The doses were administered twice daily according to per kg of body weight.

RESULTS

A significant reduction in hepatic and skeletal muscle glycogen content was exhibited. The data of qRT-PCR revealed that gene's expression of GLUT-2 was significantly decreased after treatment with ME and HF, whilst it was unaltered by AF, however, a significant decrease was observed in genes corresponding to GS, GK and HK-1 after treatment with ME. Similarly, there was a significant decrease in expression of genes corresponding to GS, GK and HK-1 following treatment with HF. Surprisingly, post-treatment with AF didn't modify the gene's expression of GS and GK, whilst it caused a profound decrease in expression of HK-1 gene. Contrarily, the expression of gene related to PK was significantly up-regulated post-administration with ME, HF and AF. The expression levels of G-6-PDH, however, remained unaltered after treatment with the experimental extract and fractions of the plant. In addition, HF and AF did not cause any modification in PEPCK, whereas ME caused a significant down-regulation of the gene. Treatment with all the extract and fractions of the plant caused a substantial decrease in the gene's expression of PC, while there was a significant increase in the expression of gene related to G-6-Pase.

CONCLUSION

The three experimental extract and fractions caused a substantial decrease in glycogen content in liver and skeletal muscle tissues. The analysis by qRT-PCR showed that glucose transport via GLUT-2 was profoundly declined by ME and HF. The expression of genes related to various metabolic pathways involved in metabolism of carbohydrate in hepatocytes revealed explicitly that the ME, HF and AF decreased the phenomena of glycogenesis and gluconeogenesis. Contrarily, all the extract and fractions of the plant activated glycogenolysis and glycolysis but did not modify the pentose phosphate shunt pathway.

Isolation and identification of bioactive compounds from chloroform fraction of methanolic extract of Carissa opaca roots

Carissa opaca is a shrub known for its variety of medicinal applications. This study reports isolation and identification of four chemical compounds from its roots for the first time. The methanolic extract of the roots was fractionated into various solvents with increasing polarity. Chloroform fraction was subjected to column and thin layer chromatography to ultimately yield 2H-cyclopropanaphthalene-2-one, 7-hydroxy-6-methoxy-2H-1-benzopyran-2-one, 3-(4-methoxyphenyl)-2,6-dimethylbenzofuran and 5(1H)-azulenone, 2,4,6,7,8,8a-hexahydro-3,8-dimethyl-4-(1-methylethylidene)-,(8S-cis). They were identified by GC-MS analysis. The compounds exhibited considerable antimicrobial activities against Bacillus subtilis, Escherichia coli, Pseudomonas aeruginosa, Candida albicans and Aspergillus niger with zones of inhibition ranging from 10 to 13 mm as compared to the standard drug amoxicillin with zones of inhibition 13-17 mm under the similar conditions. In conclusion, the roots of C. opaca can provide new leads for future antimicrobial drugs.