New sesquiterpene alpha-methylene lactones from the Egyptian plant Jasonia candicans

The sesquiterpenes with the COVID-19 Mpro inhibitory activity from the Carpesium abrotanoides L

The extract of the whole plant of Carpesium abrotanoides L. yielded four new sesquiterpenes including a novel skeleton (claroguaiane A, 1), two guaianolides (claroguaianes B-C, 2-3), and one eudesmanolide (claroeudesmane A, 4), together with three known sesquiterpenoids (5-7). The structures of the new compounds were elucidated by spectroscopic analysis especially 1D and 2D NMR spectroscopy and HRESIMS data. Additionally, all the isolated compounds were preliminarily evaluated for the inhibitive activity of COVID-19 Mpro. As a result, compound 5 showed moderate activity with an IC50 value of 36.81 μM and compound 6 exhibited a potent inhibitory effect with an IC50 value of 16.58 µM, while other compounds were devoid of noticeable activity (IC50 > 50 μM).

Bioactivity of Chitosan-Based Particles Loaded with Plant-Derived Extracts for Biomedical Applications: Emphasis on Antimicrobial Fiber-Based Systems

Marine-derived chitosan (CS) is a cationic polysaccharide widely studied for its bioactivity, which is mostly attached to its primary amine groups. CS is able to neutralize reactive oxygen species (ROS) from the microenvironments in which it is integrated, consequently reducing cell-induced oxidative stress. It also acts as a bacterial peripheral layer hindering nutrient intake and interacting with negatively charged outer cellular components, which lead to an increase in the cell permeability or to its lysis. Its biocompatibility, biodegradability, ease of processability (particularly in mild conditions), and chemical versatility has fueled CS study as a valuable matrix component of bioactive small-scaled organic drug-delivery systems, with current research also showcasing CS’s potential within tridimensional sponges, hydrogels and sutures, blended films, nanofiber sheets and fabric coatings. On the other hand, renewable plant-derived extracts are here emphasized, given their potential as eco-friendly radical scavengers, microbicidal agents, or alternatives to antibiotics, considering that most of the latter have induced bacterial resistance because of excessive and/or inappropriate use. Loading them into small-scaled particles potentiates a strong and sustained bioactivity, and a controlled release, using lower doses of bioactive compounds. A pH-triggered release, dependent on CS’s protonation/deprotonation of its amine groups, has been the most explored stimulus for that control. However, the use of CS derivatives, crosslinking agents, and/or additional stabilization processes is enabling slower release rates, following extract diffusion from the particle matrix, which can find major applicability in fiber-based systems within ROS-enriched microenvironments and/or spiked with microbes. Research on this is still in its infancy. Yet, the few published studies have already revealed that the composition, along with an adequate drug release rate, has an important role in controlling an existing infection, forming new tissue, and successfully closing a wound. A bioactive finishing of textiles has also been promoting high particle infiltration, superior washing durability, and biological response.

Cytotoxicity of 40 Egyptian plant extracts targeting mechanisms of drug-resistant cancer cells

BACKGROUND

The multidrug resistance (MDR) phenotype encounters a major challenge to the success of established chemotherapy in cancer patients. We hypothesized that cytotoxic medicinal plants with novel phytochemicals can overcome MDR and kill MDR-cells with similar efficacy as drug sensitive cells.

PURPOSE

We evaluated plant extracts from an unexplored ecosystem in Egypt with unusual climate and nutrient conditions for their activity against sensitive and multidrug-resistant cancer cell lines.

MATERIAL AND METHODS/STUDY DESIGN

Methylene chloride: methanol (1:1) and methanol: H₂O (7:3) extracts of 40 plants were prepared resulting in a sum of 76 fraction containing compounds with varying polarity. The resazurin reduction assay was employed to evaluate the cytotoxicity of these extracts on five matched pairs of drug-sensitive and their drug-resistant cell lines. Flow cytometry and Western blotting was used to determine cell cycle analyses, apoptosis, and autophagy. Reactive oxygen species (ROS) were measured spectrophotometrically.

RESULTS

Extracts derived from Withania obtusifolia (WO), Jasonia candicans (JC), Centaurea lippii (CL), and Pulicaria undulata (PU) were the most active ones among 76 extracts from 40 Egyptian medicinal plants. They showed a significant reduction of cell viability on drug-sensitive CCRF-CEM leukemia cell line with IC₅₀ values less than 7 µg/ml. Low cross-resistance degrees were observed in multidrug-resistant CEM/ADR5000 cells towards CL (1.82-fold) and JC (6.09-fold). All other drug-resistant cell lines did not reveal cross-resistance to the four extracts. Further mechanistic assessment have been studied for these four extracts.

CONCLUSION

The methylene chloride: methanol (1:1) fractions of WO, JC, CL, and PU are promising cytotoxic extracts that could be used to combat MDR cancer cells through different cell death pathways.

Bioassay-guided isolation of cytotoxic compounds from Chrysophthalmum montanum (DC.) Boiss

Bioassay-guided isolation of the 80% methanol extract of the aerial parts of Chrysophthalmum montanum (DC.) Boiss. (Asteraceae) led to the isolation of four known guaianolide-type sesquiterpene lactones, 6α-acetoxy-4α-hydroxy-1βH-guaia-9.11(13)-dien-12.8α-olide (1), 6α-acetoxy-4α-hydroxy-9β.10β-epoxy-1βH-guaia-11(13)-en-12.8α-olide (2), 4α,6α-dihydroxy-1β,5α,7αH-guaia-9(10),11(13)-dien-12,8α-olide (3), and (4α,5α,8β,10β)-4,10-dihydroxy-1,11(13)-guaidien-12,8-olide (4), along a steroidal glycoside mixture (5a and 5b). The structures of the compounds were identified on the basis of spectroscopic data. Among them, 2, 4 and a steroidal glycoside mixture were obtained from C. montanum for the first time. All isolates were also first time assayed for in vitro cytotoxicities against four human cancer cell lines, i.e. breast (MCF-7, MDA-MB 231), colon (HT-29), and lung (PC3). Among the isolates, 1-3 showed significant inhibitory effect on the proliferation of cancer cells with viability ranging from 6.86 to 26.51%, while steroidal glycoside mixture showed no cytotoxicity, except against HT-29 (viability 61.99%). Compound 4 exhibited strong and selective cell growth inhibition against HT-29 with viability 20.99% and was identified as a promising compound with high selectivity between cancer cells and normal human lung cells (BEAS-2B), especially against HT-29 (IC₅₀ = 12.2 μg/mL) compared to that of cisplatin. These results suggested that 4 is worthy of further study to determine its cytotoxicity mechanisms.

The antiproliferative effects of cold atmospheric plasma-activated media on different cancer cell lines, the implication of ozone as a possible underlying mechanism

Recent studies have proven several promising anticancer activities for cold atmospheric plasma (CAP) against a wide range of cancer cells in vitro. Recently, media treated with CAP have also found to effectively eradicate cancer cells similar to the CAP. Based on advantages, many researchers prefer to apply CAP-activated media (PAM) as an alternative to cap in the treatment of cancer. However, less has been achieved regarding the anticancer effects and anticancer mechanisms of PAM. Investigating the selective anticancerous activities of PAM, the viability of SKBR3, MCF7, ASPC-1, A-549, G-292, and SW742 cancer cell lines, as well as normal human skin fibroblasts (FMGB-1) and MCF10A cells in relation to the media activation time, and the length of exposure was studied. Also, we examined the concentration of ozone in media as a function to CAP activation time since recent studies have proposed ozone as a pivotal reactive species in the induction of cell death. Based on the result, both increasing the duration of media activation time and the length of exposure to PAM could significantly increase the anticancer activity. Nevertheless, the cytotoxicity on normal cells was either not affected or slightly increased. Among the six tested cancer cell lines, SW742 was the most resistant and SKBR3 the most susceptible cancer cell lines to PAM. Also, increasing duration of treatment with CAP resulted in a significant rise in O₃ concentration levels in media. Overall, these results suggest PAM, as a promising tool in the treatment of different cancers and O ₃ formation as a probable underlying mechanism.

Phytochemistry and Pharmacological Studies of Citrus macroptera: A Medicinal Plant Review

Citrus macroptera (family Rutaceae), commonly known as Sat Kara, is a pharmacologically diverse medicinal plant. Various parts of this plant, specifically fruit, have an immense range of medicinal uses in folk medicine directed for a number of ailments. A plethora of active phytochemical constituents of this plant have been revealed so far, namely, limonene, beta-caryophyllene, beta-pinene, geranial edulinine, ribalinine, isoplatydesmine, and so forth. Several studies demonstrated the exploration of pharmacological potential of various parts such as fruits, leaves, and stems of C. macroptera as antioxidant, cytotoxic, antimicrobial, thrombolytic, hypoglycemic, anxiolytic, antidepressant, cardioprotective, and hepatoprotective. Furthermore, inhibition of in vitro α-amylase, inhibition of paracetamol induced hepatotoxicity, and potentiation of brain antioxidant enzyme are also ascertained. In present review, comprehensive study focused on knowledge regarding several phytopharmacological activities of Citrus macroptera has been described.

Evaluation of antibacterial, antifungal and modulatory activity of methanol and ethanol extracts of Padina sanctae-crucis

BACKGROUND

Multi-resistantmicroorganisms such as Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, Candida tropicalis e Candida krusei are the main causes of microbial infections. Padina sanctae-crucis is a seaweed often used to check the contamination of ecosystems by materials such as heavy metals, but studies of the antimicrobial activity of the same seaweed were not found.

METHODS

The tests for the minimum inhibitory concentration and modulation of microbial resistance, with the use of ethanolic and methanolic extracts of Padina Sanctae-cruces combined with drugs of the class of aminoglycosides and antifungal were used to evaluate the activity against the cited microorganisms.

RESULTS

Was observed a modulation of antibiotic activity between the natural products and the E. coli and S. aureus strains, indicating a synergism and antagonism respectively.

CONCLUSIONS

The results showed a moderate modulatory effect against some microorganisms studied.

Phytochemical screening, antibacterial activity and in vitro interactions between Costus cf. arabicus L. with UV-A and aminoglycosides

In this study, the methanol extracts of of Costus cf. arabicus L. were evaluated for antibacterial activity against multiresistant strains of Escherichia coli and Staphylococcus aureus. The antibacterial and modulatory activity of the extracts was assayed by microdilution. The light-enhanced antibacterial activity was assayed by light regimen. The growth of the bacteria tested was not inhibited by the extracts. The minimum inhibitory concentration (MIC) values ranged from 512 to ≥1024 µg·m L(-1). However, the antibiotic activity of the aminoglycosides was synergistically enhanced when these extracts were associated in sub-inhibitory concentrations with the antibiotics. Both extracts showed activity against at two standard bacterial strains. Because of this, we suggest that the ethanol extracts of the stems and leaves of Costus cf. arabicus L. show potential antibacterial, light-induced and synergistic antibiotic activity. With such results, these extracts are proven to be a promising source of antibacterial and modulatory agents.

In vitro antimicrobial activity of ten medicinal plants against clinical isolates of oral cancer cases

Background

Suppression of immune system in treated cancer patients may lead to secondary infections that obviate the need of antibiotics. In the present study, an attempt was made to understand the occurrence of secondary infections in immuno-suppressed patients along with herbal control of these infections with the following objectives to: (a) isolate the microbial species from the treated oral cancer patients along with the estimation of absolute neutrophile counts of patients (b) assess the in vitro antimicrobial activity medicinal plants against the above clinical isolates.

Methods

Blood and oral swab cultures were taken from 40 oral cancer patients undergoing treatment in the radiotherapy unit of Regional Cancer Institute, Pt. B.D.S. Health University,

Rohtak, Haryana. Clinical isolates were identified by following general microbiological, staining and biochemical methods. The absolute neutrophile counts were done by following the standard methods. The medicinal plants selected for antimicrobial activity analysis were Asphodelus tenuifolius Cav., Asparagus racemosus Willd., Balanites aegyptiaca L., Cestrum diurnum L., Cordia dichotoma G. Forst, Eclipta alba L., Murraya koenigii (L.) Spreng. , Pedalium murex L., Ricinus communis L. and Trigonella foenum graecum L. The antimicrobial efficacy of medicinal plants was evaluated by modified Kirby-Bauer disc diffusion method. MIC and MFC were investigated by serial two fold microbroth dilution method.

Results

Prevalent bacterial pathogens isolated were Staphylococcus aureus (23.2%), Escherichia coli (15.62%), Staphylococcus epidermidis (12.5%), Pseudomonas aeruginosa (9.37%), Klebsiella pneumonia (7.81%), Proteus mirabilis (3.6%), Proteus vulgaris (4.2%) and the fungal pathogens were Candida albicans (14.6%), Aspergillus fumigatus (9.37%). Out of 40 cases, 35 (87.5%) were observed as neutropenic. Eight medicinal plants (A. tenuifolius, A. racemosus, B. aegyptiaca, E. alba, M. koenigii, P. murex R. communis and T. foenum graecum) showed significant antimicrobial activity (P < .05) against most of the isolates. The MIC and MFC values were ranged from 31 to 500 μg/ml. P. aeruginosa was observed highest susceptible bacteria (46.6%) on the basis of susceptible index.

Conclusion

It can be concluded that treated oral cancer patients were neutropenic and prone to secondary infection of microbes. The medicinal plant can prove as effective antimicrobial agent to check the secondary infections in treated cancer patients.

WITHDRAWN: Phytochemical screening and modulation of antibiotic activity by Ocimum gratissimum L

The Publisher regrets that this article is an accidental duplication of an article that has already been published, http://dx.doi.org/10.1016/j.bionut.2010.09.007. The duplicate article has therefore been withdrawn.

Isolation and identification of antimicrobial compound from Mentha longifolia L. leaves grown wild in Iraq

Background

Mentha longifolia L. (Lamiaceae) leaves have been traditionally implemented in the treatment of minor sore throat and minor mouth or throat irritation by the indigenous people of Iraq, although the compounds responsible for the medicinal properties have not been identified. In the present study, an antimicrobial compound was isolated and characterized, and its biological activity was assessed.

Methods

The compound was isolated and characterized from the extracted essential oil using different spectral techniques: TLC, FTIR spectra and HPLC. Antimicrobial activity of the compound was assessed using both disc diffusion and microdilution method in 96 multi-well microtiter plates.

Results

A known compound was isolated from the essential oil of the plant and was identified as (-) menthol. The isolated compound was investigated for its antimicrobial activity against seven selected pathogenic and non-pathogenic microorganisms: Staphylococcus aureus, Streptococcus mutans, Streptococcus faecalis, Streptococcus pyogenis, Lactobacillus acidophilus, Pseudomonas aeruginosa and the yeast Candida albicans. Menthol at different concentrations (1:1, 1:5, 1:10, 1:20) was active against all tested bacteria except for P. aeruginosa, and the highest inhibitory effect was observed against S. mutans (zone of inhibition: 25.3 mm) using the disc diffusion method. Minimal inhibitory concentration MIC values ranged from 15.6–125.0 μg/ml, and the most promising results were observed against S. aureus and S. mutans (MIC 15.6 μg/ml) while, S. faecalis, S. pyogenis and L. acidophilus ranked next (MIC 31.2 μg/ml). Furthermore, menthol achieved considerable antifungal activity against the yeast C. albicans (zone of inhibition range: 7.1–18.5 mm; MIC: 125.0).

Conclusion

The isolation of an antimicrobial compound from M. longifolia leaves validates the use of this plant in the treatment of minor sore throat and minor mouth or throat irritation.

Therapeutic Potential of Plants as Anti-microbials for Drug Discovery

The uses of traditional medicinal plants for primary health care have steadily increased worldwide in recent years. Scientists are in search of new phytochemicals that could be developed as useful anti-microbials for treatment of infectious diseases. Currently, out of 80% of pharmaceuticals derived from plants, very few are now being used as anti-microbials. Plants are rich in a wide variety of secondary metabolites that have found anti-microbial properties. This review highlights the current status of traditional medicine, its contribution to modern medicine, recent trends in the evaluation of anti-microbials with a special emphasis upon some tribal medicine, in vitro and in vivo experimental design for screening, and therapeutic efficacy in safety and human clinical trails for commercial outlet. Many of these commercially available compounds are crude preparations administered without performing human clinical trials. Recent methods are useful to standardize the extraction for scientific investigation of new phytochemicals and anti-microbials of traditionally used plants. It is concluded that once the local ethnomedical preparations of traditional sources are scientifically evaluated before dispensing they should replace existing drugs commonly used for the therapeutic treatment of infection. This method should be put into practice for future investigations in the field of ethnopharmacology, phytochemistry, ethnobotany and other biological fields for drug discovery.

A new alpha-methylene gamma-lactone sesquiterpene from Hedyosmum arborescens

A new sesquiterpene lactone, 7alpha,10alpha-epoxy-1alpha(H),5alpha(H)-guaia-3,11(13)-dien-8alpha,12-olide, was isolated from the leaves of Hedyosmum arborescens. The structure of this unusual 7,10-epoxy-guaianolide was determined by spectroscopic methods, particularly one- and two-dimensional 1H and 13C NMR.

Jasomontanone, a Novel Bicyclic Sesquiterpene from the Leaves of Jasonia montana

A novel rearranged eudesmane sesquiterpene with a new 5/7 membered bicyclic-ring-system, jasomontanone, was isolated from Jasonia montana. Its structure was determined as (3a R*, 6 R*, 8a R)-3a-(hydroxymethyl)-6-(2-hydroxy-propan-2-yl)-8a-methyl-octahydrazulen-4(5 H)-one by analysis of spectroscopic data (IR, HR-MS, 1H and 13C NMR), including 2D NMR (1H-1H COSY, HMQC, HMBC and NOESY), chemical transformation, and biogenetic consideration.

Sesquiterpene lactones from Pulicaria crispa

The investigation of Pulicaria crispa gave a new guaianolide identified as 1 beta,4 beta-dihydroxy-5 alpha (H)-guaia-10(14),11(13)-dien-8 alpha,12-olide (5).

Plant products as antimicrobial agents

The use of and search for drugs and dietary supplements derived from plants have accelerated in recent years. Ethnopharmacologists, botanists, microbiologists, and natural-products chemists are combing the Earth for phytochemicals and "leads" which could be developed for treatment of infectious diseases. While 25 to 50% of current pharmaceuticals are derived from plants, none are used as antimicrobials. Traditional healers have long used plants to prevent or cure infectious conditions; Western medicine is trying to duplicate their successes. Plants are rich in a wide variety of secondary metabolites, such as tannins, terpenoids, alkaloids, and flavonoids, which have been found in vitro to have antimicrobial properties. This review attempts to summarize the current status of botanical screening efforts, as well as in vivo studies of their effectiveness and toxicity. The structure and antimicrobial properties of phytochemicals are also addressed. Since many of these compounds are currently available as unregulated botanical preparations and their use by the public is increasing rapidly, clinicians need to consider the consequences of patients self-medicating with these preparations.

Clerodane diterpenoids, long chain esters of coumaric acid and other compounds from Baccharis myrsinites

A new clerodane diterpenoid and two new long chain esters of trans- and cis-coumaric acid, in addition to known triterpenoids and one known clerodane diterpenoid, have been isolated and characterized from Baccharis myrsinites. The structures were determined by spectroscopic techniques.