High-performance thin layer chromatography-based phytochemical and bioactivity characterisation of anticancer endophytic fungal extracts derived from marine plants

Fabrication and optimization of itraconazole-loaded zein-based nanoparticles in coated capsules as a promising colon-targeting approach pursuing opportunistic fungal infections

Itraconazole (ITZ), a broad-spectrum antifungal drug, was formulated into colon-targeting system aiming to treat opportunistic colonic fungal infections that commonly infect chronic inflammatory bowel diseases (IBD) patients due to immunosuppressive therapy. Antisolvent precipitation technique was employed to formulate ITZ-loaded zein nanoparticles (ITZ-ZNPs) using various zein: drug and aqueous:organic phase ratios. Central composite face-centered design (CCFD) was used for statistical analysis and optimization. The optimized formulation was composed of 5.5:1 zein:drug ratio and 9.5:1 aqueous:organic phase ratio with its observed particle size, polydispersity index, zeta potential, and entrapment efficiency of 208 ± 4.29 nm, 0.35 ± 0.04, 35.7 ± 1.65 mV, and 66.78 ± 3.89%, respectively. ITZ-ZNPs were imaged by TEM that revealed spherical core-shell structure, and DSC proved ITZ transformation from crystalline to amorphous form. FT-IR showed coupling of zein NH group with ITZ carbonyl group without affecting ITZ antifungal activity as confirmed by antifungal activity test that showed enhanced activity of ITZ-ZNPs over the pure drug. Histopathological examination and cytotoxicity tests ensured biosafety and tolerance of ITZ-ZNPs to the colon tissue. The optimized formulation was then loaded into Eudragit S100-coated capsules and both in vitro release and in vivo X-ray imaging confirmed the success of such coated capsules in protecting ITZ from the release in stomach and intestine while targeting ITZ to the colon. The study proved that ITZ-ZNPs is promising and safe nanoparticulate system that can protect ITZ throughout the GIT and targeting its release to the colon with effectual focused local action for the treatment of colon fungal infections.

Diversity, Antimicrobial, Antioxidant, and Anticancer Activity of Culturable Fungal Endophyte Communities in Cordia dichotoma

Endophytic fungi are a significant source of secondary metabolites, which are chemical compounds with biological activities. The present study emphasizes the first-time isolation and identification of such fungi and their pharmacological activities from the medicinal plant Cordia dichotoma, which is native to Jammu, India. The Shannon Wiener diversity index revealed a wide range of fungal endophytes in root (1.992), stem (1.645), and leaf (1.46) tissues. A total of 19 endophytic fungi belonging to nine different genera were isolated from this plant and the majority belonged to the Ascomycota phylum. ITS rRNA gene sequencing was used to identify the fungal strains and they were submitted in NCBI GenBank. The most potent fungal isolate Cladosporium cladosporioides OP870014 had strong antimicrobial, antioxidant, and anticancer activity against MCF-7, HCT-116, and PC-3 cancer cell lines. The LC-MS and GC-MS analyses of the ethyl acetate extract of C. cladosporioides were examined to identify the bioactive metabolites. The major compounds of the crude extract derived from C. cladosporioides OP870014, according to GC-MS, are spiculisporic acid; dibutyl phthalate; phenylethyl alcohol; cyclohexanone, 2,3,3-trimethyl-2-3-methylbutyl; pyrrolo[1,2-a]pyrazine-1,4-dione,hexahydro-3-(phenylmethyl);2,5-piperazinedione,3,6-bis(2-methylpropyl); and heneicosane which possessed antimicrobial, anticancerous, and antioxidant activities. The findings revealed that C. dichotoma has the capacity to host a wide variety of fungal endophytes and that secondary metabolites from the endophytic fungus may be a source of alternative naturally occurring antimicrobial, antioxidant, and cytotoxic compounds.

Fungal Endophytes: Microfactories of Novel Bioactive Compounds with Therapeutic Interventions; A Comprehensive Review on the Biotechnological Developments in the Field of Fungal Endophytic Biology over the Last Decade

The seminal discovery of paclitaxel from endophytic fungus Taxomyces andreanae was a milestone in recognizing the immense potential of endophytic fungi as prolific producers of bioactive secondary metabolites of use in medicine, agriculture, and food industries. Following the discovery of paclitaxel, the research community has intensified efforts to harness endophytic fungi as putative producers of lead molecules with anticancer, anti-inflammatory, antimicrobial, antioxidant, cardio-protective, and immunomodulatory properties. Endophytic fungi have been a valuable source of bioactive compounds over the last three decades. Compounds such as taxol, podophyllotoxin, huperzine, camptothecin, and resveratrol have been effectively isolated and characterized after extraction from endophytic fungi. These findings have expanded the applications of endophytic fungi in medicine and related fields. In the present review, we systematically compile and analyze several important compounds derived from endophytic fungi, encompassing the period from 2011 to 2022. Our systematic approach focuses on elucidating the origins of endophytic fungi, exploring the structural diversity and biological activities exhibited by these compounds, and giving special emphasis to the pharmacological activities and mechanism of action of certain compounds. We highlight the tremendous potential of endophytic fungi as alternate sources of bioactive metabolites, with implications for combating major global diseases. This underscores the significant role that fungi can play in the discovery and development of novel therapeutic agents that address the challenges posed by prevalent diseases worldwide.

Antimicrobial properties and biotransforming ability of fungal endophytes from Ficus carica L. (Moraceae)

The endophytic fungal community associated with leaves of Ficus carica L. (Moraceae) from Argentina was investigated. Fifteen fungal isolates were isolated and identified by molecular methods into the genera Alternaria, Cladosporium, Curvularia, Diaporthe, Epicoccum, Myrothecium, Neofusicoccum, Nigrospora, Preussia and Ustilago. Cladosporium cladosporioides and Curvularia lunata were the most frequently isolated species. The fungal metabolic profiles were obtained by automated TLC and NMR and analysed by PC Analysis. Antifungal and antibacterial activity was assessed by bioautographic assays. In addition, the biotransforming ability of the fungal isolates was tested on F. carica extracts. Five isolates (33.3%) exhibited inhibitory activity against at least one of the microorganisms tested. Most of the fungal endophytes were able to metabolise the flavonoid rutin 1, and the coumarin psoralen 3 present in F. carica extracts. Further investigations of the psoralen biotransforming ability performed by the selected endophyte Alternaria alternata F8 showed the accumulation of the 6,7-furan-hydrocoumaric acid derivative 4 as the main biotransformation product. Our results corroborate that F. carica can live symbiotically with rich and diverse endophytic communities adding insights about their ecological interactions.

In Vitro Efficacy of Extracts and Isolated Bioactive Compounds from Ascomycota Fungi in the Treatment of Colorectal Cancer: A Systematic Review

Colorectal cancer (CRC) is the second leading cause of cancer-related deaths worldwide. Despite the advances and success of current treatments (e.g., chemotherapy), there are multiple serious side effects which require the development of new treatment strategies. In recent years, fungi have gained considerable attention as a source of extracts and bioactive compounds with antitumor capabilities because of their antimicrobial and antioxidant properties and even their anti-inflammatory and antiviral activities. In the present review, a systematic search of the existing literature in four electronic databases was carried out in which the antitumor activity against CRC cells of Ascomycota fungi extracts or compounds was tested. The systematical research in the four databases resulted in a total of 883 articles. After applying exclusion and inclusion criteria, a total of 75 articles were finally studied. The order Eurotiales was the most studied (46% of the articles), and the ethyl acetate extraction was the most used method (49% of the papers). Penicillium extracts and gliotoxin and acetylgliotoxin G bioactive compounds showed the highest cytotoxic activity. This review also focuses on the action mechanisms of the extracts and bioactive compounds of fungi against CRC, which were mediated by apoptosis induction and the arrest of the cell cycle, which induces a notable reduction in the CRC cell proliferation capacity, and by the reduction in cell migration that limits their ability to produce metastasis. Thus, the ability of fungi to induce the death of cancer cells through different mechanisms may be the basis for the development of new therapies that improve the current results, especially in the more advanced stages of the CCR.

In Vitro and In Silico Antioxidant Efficiency of Bio-Potent Secondary Metabolites From Different Taxa of Black Seed-Producing Plants and Their Derived Mycoendophytes

Oxidative stress is involved in the pathophysiology of multiple health complications, and it has become a major focus in targeted research fields. As known, black seeds are rich sources of bio-active compounds and widely used to promote human health due to their excellent medicinal and pharmaceutical properties. The present study investigated the antioxidant potency of various black seeds from plants and their derived mycoendophytes, and determined the total phenolic and flavonoid contents in different extracts, followed by characterization of major constituents by HPLC analysis. Finally, in silico docking determined their binding affinities to target myeloperoxidase enzymes. Ten dominant mycoendophytes were isolated from different black seed plants. Three isolates were then selected based on high antiradical potency and further identified by ITS ribosomal gene sequencing. Those isolated were Aspergillus niger TU 62, Chaetomium madrasense AUMC14830, and Rhizopus oryzae AUMC14823. Nigella sativa seeds and their corresponding endophyte A. niger had the highest content of phenolics in their n-butanol extracts (28.50 and 24.43 mg/g), flavonoids (15.02 and 11.45 mg/g), and antioxidant activities (90.48 and 81.48%), respectively, followed by Dodonaea viscosa and Portulaca oleracea along with their mycoendophytic R. oryzae and C. madrasense. Significant positive correlations were found between total phenolics, flavonoids, and the antioxidant activities of different tested extracts. The n-butanol extracts of both black seeds and their derived mycoendophytes showed reasonable IC50 values (0.81–1.44 mg/ml) compared to the control with significant correlations among their phytochemical contents. Overall, seventeen standard phenolics and flavonoids were used, and the compounds were detected in different degrees of existence and concentration in the examined extracts through HPLC analysis. Moreover, the investigation of the molecular simulation results of detected compounds against the myeloperoxidase enzyme revealed that, as a targeted antioxidant, rutin possessed a high affinity (−15.3184 kcal/mol) as an inhibitor. Taken together, the black seeds and their derived mycoendophytes are promising bio-prospects for the broad industrial sector of antioxidants with several valuable potential pharmaceutical and nutritional applications.

Exploring Marine as a Rich Source of Bioactive Peptides: Challenges and Opportunities from Marine Pharmacology

This review highlights the underexplored potential and promises of marine bioactive peptides (MBPs) with unique structural, physicochemical, and biological activities to fight against the current and future human pathologies. A particular focus is given to the marine environment as a significant source to obtain or extract high-value MBPs from touched/untouched sources. For instance, marine microorganisms, including microalgae, bacteria, fungi, and marine polysaccharides, are considered prolific sources of amino acids at large, and peptides/polypeptides in particular, with fundamental structural sequence and functional entities of a carboxyl group, amine, hydrogen, and a variety of R groups. Thus, MBPs with tunable features, both structural and functional entities, along with bioactive traits of clinical and therapeutic value, are of ultimate interest to reinforce biomedical settings in the 21st century. On the other front, as the largest biome globally, the marine biome is the so-called "epitome of untouched or underexploited natural resources" and a considerable source with significant potentialities. Therefore, considering their biological and biomedical importance, researchers around the globe are redirecting and/or regaining their interests in valorizing the marine biome-based MBPs. This review focuses on the widespread bioactivities of MBPs, FDA-approved MBPs in the market, sustainable development goals (SDGs), and legislation to valorize marine biome to underlying the impact role of bioactive elements with the related pathways. Finally, a detailed overview of current challenges, conclusions, and future perspectives is also given to satisfy the stimulating demands of the pharmaceutical sector of the modern world.

Assessment of Biological Activities of Fungal Endophytes Derived Bioactive Compounds Isolated from Amoora rohituka

Fungal endophytes have remarkable potential to produce bioactive compounds with numerous pharmacological significance that are used in various disease management and human welfare. In the current study, a total of eight fungal endophytes were isolated from the leaf tissue of Amoora rohituka, and out of which ethyl acetate (EA) extract of Penicillium oxalicum was found to exhibit potential antioxidant activity against DPPH, nitric oxide, superoxide anion and hydroxyl free radicals with EC₅₀ values of 178.30 ± 1.446, 75.79 ± 0.692, 169.28 ± 0.402 and 126.12 ± 0.636 µg/mL, respectively. The significant antioxidant activity of EA extract of P. oxalicum is validated through highest phenolic and flavonoid content, and the presence of unique bioactive components observed through high-performance thin layer chromatography (HPTLC) fingerprinting. Moreover, EA extract of P. oxalicum also displayed substantial anti-proliferative activity with IC₅₀ values of 56.81 ± 0.617, 37.24 ± 1.26 and 260.627 ± 5.415 µg/mL against three cancer cells HuT-78, MDA-MB-231 and MCF-7, respectively. Furthermore, comparative HPTLC fingerprint analysis and antioxidant activity of P. oxalicum revealed that fungal endophyte P. oxalicum produces bioactive compounds in a host-dependent manner. Therefore, the present study signifies that fungal endophyte P. oxalicum associated with the leaf of A. rohituka could be a potential source of bioactive compounds with antioxidant and anticancer activity.

Antioxidative-, Antimicrobial-, Enzyme Inhibition-, and Cytotoxicity-Based Fractionation and Isolation of Active Components from Monotheca buxifolia (Falc.) A. DC. Stem Extracts

The current study elaborates the pharmacological potential of the methanolic extract and its fractions of the stems of Monotheca buxifolia based on thin-layer chromatography and column chromatography analyses, exploiting biological and phytochemical assays. The results suggest that bioassay-guided isolation and fractionation led to the accumulation of biologically active components in the most active fractions that resulted in the isolation of different compounds. Structural elucidation of the purified compounds was accomplished using spectroscopic one-dimensional (¹H, ¹³C) and two-dimensional NMR (heteronuclear multiple quantum coherence, heteronuclear multiple bond coherence, and correlation spectroscopy) and spectrometric (electron ionization mass spectrometry and high-resolution electron ionization mass spectrometry) techniques. The n-hexane, CHCl₃, and EtAOc fractions led to the isolation of lupeol from different fractions. 1-Triacontanol was also isolated from the n-hexane fraction, while benzoic acid, methyl benzoate, ursolic acid, and 3-hydroxybenzoic acid were obtained from the EtOAc fraction. The compounds depicted good-to-moderate total antioxidative potential and total reducing power activity and significant free-radical scavenging activity. All the compounds showed significant urease and lipase inhibitory activity with poor-to-moderate amylase inhibition. Significant zone of inhibition was observed against different bacterial strains by the isolated compounds. This work therefore states that bioassay-guided isolation plays a vital role in the isolation of biologically active constituents that can be exploited for drug development.

High-performance thin-layer chromatography based approach for bioassay and ATR-FTIR spectroscopy for the evaluation of antioxidant compounds from Asparagus racemosus Willd. aerial parts

Asparagus racemosus Willd. is widely used to combat various diseases owing to its medicinal properties. In this study, arial parts of A. racemosus were investigated for their total phenolic content, total flavonoid content and antioxidative potential. A high-performance thin-layer chromatography (HPTLC) method combined with effect-directed-analysis was also developed to screen the antioxidant effects of A. racemosus and quantify biologically active compounds on chromatograms from A. racemosus. Total phenolics (154 mg gallic acid equivalent/g), flavonoid contents (497 mg quercetin/g) and IC₅₀ (15.25 μg/ml) were found to be higher in methanolic extract of A. racemosus than in n-hexane, chloroform and ethyl acetate extracts. HPTLC hyphenated with chemical derivatizations (DPPH•, p-anisaldehyde/sulfuric acid, and ferric chloride) was used to evaluate antioxidant activity and the presence of phytosterols, terpenoids and polyphenolic contents. The same compounds at 100*retention factor = 58, 68, 74 and 65 in extracts were responsible for antioxidant activity. Hyphenated HPTLC allowed a rapid characterization of the active compound with a combination of effect-directed-analysis and attenuated total reflectance-Fourier transform infrared spectroscopy. Spectral analysis of the band from attenuated total reflectance identified myricetin, quercetin, p-coumaric acid and caffeic acid as responsible for the antioxidant activity.

The effect of extractive lacto-fermentation on the bioactivity and natural products content of Pittosporum angustifolium (gumbi gumbi) extracts

Pittosporum angustifolium, known as gumbi gumbi, is a native Australian plant, which has traditionally been used as an Aboriginal medicine. This study investigates the effect of different solvents and extractive fermentation on the content and natural products composition of Pittosporum angustifolium extracts, and compares their antioxidant activity, in vitro α-amylase inhibition, and anti-inflammatory properties. Anti-inflammatory activity of the extracts was determined by measuring the inhibition of nitric oxide (NO) production. Extracts were characterised with FTIR-ATR spectroscopy, and screened for antioxidant activities and α-amylase inhibitory activity via High-performance thin-layer chromatography (HPTLC)-Effect-directed analysis (EDA) with direct bioautography. HPTLC combined with chemical derivatization and bioassays was used for EDA screening. The results show that lactic acid fermentation of gumbi gumbi leaves boosts the antioxidant activity in extracts by increasing the total phenolic content, but does not affect (increase or decrease) α-amylase inhibitory activity or nitrogen scavenging/anti-inflammatory activity. Analysis of the ATR-FTIR spectra from the band at R_F = 0.85 that inhibits α-amylase, suggests that fatty acid esters are responsible for the enzyme inhibition; both saturated fatty acid esters in unfermented extracts and unsaturated fatty acid esters in fermented extracts. The ATR-FTIR spectra of the polyphenolics in fermented extracts (R_F = 0.15-0.20) suggests the presence of soluble lignin fragments (i.e. lignins depolymerized into monomers and oligomers during the fermentation process).