Evaluation of the Antioxidant Activities and Tyrosinase Inhibitory Property from Mycelium Culture Extracts

Thiazol-4(5H)-one analogs as potent tyrosinase inhibitors: Synthesis, tyrosinase inhibition, antimelanogenic effect, antioxidant activity, and in silico docking simulation

As the β-phenyl-α,β-unsaturated carbonyl (PUSC) structure was previously identified to play a key role in tyrosinase inhibition, 14 analogs with a PUSC structure built on a thiazol-4(5H)-one scaffold were synthesized using Knoevenagel condensation to serve as potential tyrosinase inhibitors. Through mushroom tyrosinase inhibition experiments, two analogs 9 and 11 were identified as potent tyrosinase inhibitors, with 11 exhibiting an IC50 value of 0.4 ± 0.01 μM, which indicates its 26-fold greater potency than kojic acid. Kinetic studies using Lineweaver-Burk plots revealed that 9 and 11 are competitive and mixed-type inhibitors, respectively; these kinetic results were supported by docking simulations. According to the B16F10 cell-based experiments, 9 and 11 inhibited melanogenesis more effectively than kojic acid due to their potent cellular tyrosinase inhibitory activity. In addition, analogs 9 and 11 exhibited moderate-to-strong antioxidant capacity, scavenging ABTS+, DPPH, and ROS radicals. In particular, analog 12 with a catechol moiety exhibited very strong ROS-scavenging activity, similar to Trolox. These results suggest that analogs 9 and 11, which exhibit potent tyrosinase inhibitory activity in mushroom and mammalian cells and anti-melanogenic effects in B16F10 cells, are promising antibrowning agents for crops and skin lightening agents for hyperpigmentation-related diseases.

Anti-tyrosinase flavone derivatives and their anti-melanogenic activities: Importance of the β-phenyl-α,β-unsaturated carbonyl scaffold

Flavone derivatives were designed and synthesized based on the hypothesis that flavones containing the β-phenyl-α,β-unsaturated carbonyl (PUSC) scaffold have potential anti-tyrosinase activity. Flavones 1a and 1e inhibited mushroom tyrosinase more potently than kojic acid, and 1e inhibited monophenolase and diphenolase 61- and 28-fold more than kojic acid, respectively. Kinetic studies on mushroom tyrosinase indicated that 1a and 1e competitively inhibit monophenolase and diphenolase, and docking results supported these results. In an in vitro assay using B16F10 murine cells, 1a and 1e inhibited melanin production more potently than kojic acid, and this was attributed to the inhibition of tyrosinase. Furthermore, 1a and 1e strongly scavenged DPPH and ABTS radicals and ROS, which suggested that their antioxidant properties were at least partly responsible for their anti-melanogenic effects. Moreover, flavone 1a also inhibited the gene expressions of the melanogenesis-related genes tyrosinase, tyrosinase-related protein (TRP)-1, and TRP-2. Our findings that flavone derivatives (i) directly inhibit tyrosinase, (ii) act as antioxidants, and (iii) inhibit the expressions of melanogenesis-related genes suggest their potential use as natural melanogenesis inhibitors. Furthermore, the study confirms that the PUSC scaffold confers anti-tyrosinase activity.

Nanoemulsion Containing Kojic Dipalmitate and Rosehip Oil: A Promising Formulation to Treat Melasma

Melasma is a hard-to-treat hyperpigmentation disorder. Combined incorporation of kojic dipalmitate (KDP), the esterified form of kojic acid, and rosehip oil, an oil with antioxidant and skin-regenerating properties, into nanocarrier systems appears to be a suitable strategy to develop high-performance formulations. A high-energy method (Ultra-Turrax^®) was used to develop nanoemulsions containing up to 2 mg/mL KDP, 5% rosehip oil, and 7.5% surfactant. Formulations were characterized regarding droplet size, size distribution, pH, density, morphology, KDP content, incorporation efficiency, and stability under different temperature conditions. A scale-up study was conducted. Skin permeation, antioxidant potential, and tyrosinase inhibitory activity were assessed in vitro. Cell viability studies were also performed. Results showed that nanoemulsions containing 1 and 2 mg/mL KDP had incorporation efficiencies greater than 95%, droplet size smaller than 130 nm, suitable size distribution, zeta potential of approximately -10 mV, and good stability over 30 days of refrigerated storage. The nanoemulsion containing 1 mg/mL KDP was chosen for further evaluation because it had lower nanocrystal formation, greater scale-up feasibility and allowed KDP permeation up to the epidermis similarly than observed for 2 mg/mL KDP. This formulation (1 mg/mL KDP) showed antioxidant and depigmenting efficacy, close to that of 1 mM ascorbic acid. No cytotoxicity was observed in formulations concentrations ranging from 0.06% to 1%.

Comparison of Phytochemical Constituents and Pharmacological Activities of Various Solvent Extracts Obtained from Millettia speciosa Stem Powder

Millettia speciosa is a plant extensively used as an important component in Chinese herbal medicine and food-based medicines. The present study was carried out to determine the total flavonoid content (TFC), volatile phytoconstituents, and pharmacological activities, i.e., antityrosinase, sunscreen, and anticancer activity, of different fractions of M. speciosa stem. Different organic solvents of increasing polarity, i.e., petroleum ether (PE), ethyl acetate (EtOAc), and methanol (MeOH), were used for extraction. The highest total flavonoid content, i.e., 48.30 ± 0.90%, was reported for PE extract. Various important phytocomponents were revealed by gas chromatography-mass spectroscopy (GC-MS) analysis. Based on abundance, the major compounds were n-hexadecanoic acid (16.654%), n-hexadecanoic acid (14.808%), and beta-sitosterol (6.298%) for PE, EtOAc, and MeOH extract, respectively. The significant antityrosinase activity, i.e., 70.97 ± 0.66%, with an IC₅₀ value of 4.58 mg/mL was noted for PE extract followed by EtOAc extract, i.e., 59.84 ± 0.67%, with IC₅₀ value of 6.10 mg/mL. The maximum sunscreen activity was reported for PE extract exhibiting the maximum absorbance value (0.633 ± 0.06) in the ultraviolet (UV) region, i.e., UVC, while EtOAc extract showed the second highest level of absorbance in the UVB range, i.e., 0.632 ± 0.07. The strongest anticancer activity (49.73 ± 0.49% cell viability) towards MCF-7 breast cancer cell line was reported for PE extract with IC₅₀ 197.51 μg/mL. Our results confirmed the presence of potential therapeutic components for each extract with significant biological functions, showing the importance of the M. speciosa stem as a source of biomedicine. To our knowledge, this is the first report on M. speciosa stem extending comprehensive research about its phytochemical profile and various significant pharmacological activities.

Biological Characterization and Quantification of Rambutan (Nephelium lappaceum L.) Peel Extract as a Potential Source of Valuable Minerals and Ellagitannins for Industrial Applications

This study extracted ellagitannins from rambutan peel using the Soxhlet technique. The extract was further partitioned and fractionated to get extract rich in ellagitannin and geraniin, respectively. The partitioning of the extract significantly increased total phenolic content (TPC) by 36.3% and its biological properties. Mineral elements such as Ca, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, and Zn were identified in both peel and extract. Ellagitannins such as geraniin and corilagin with metabolites (gallic acid and ellagic acid) were identified as the major compounds. Analysis of antioxidant activities shows that the ellagitannin rich extract is as powerful as vitamin C. Geraniin was the main contributor to the free radical scavenging activity. The study also revealed that extract with a fraction rich in geraniin has antioxidant activity equivalent to commercial geraniin (1.56 ± 0.11 Trolox equivalent g/g). It also showed low cytotoxicity on fibroblast L929 cells, moderate tyrosinase activity, and good efficacy against Staphylococcus aureus, Staphylococcus epidermidis, and Cutibacterium acnes strains. Successive fractionation of the extract is a promising technique to produce geraniin rich fractions with enhanced antioxidant property. Rambutan peel, as a natural product, is a good source of mineral elements and biologically active compounds for pharmaceutical, nutraceutical, and cosmetic formulations.

Anti-Melanogenesis Activity of Crocodile (Crocodylus siamensis) White Blood Cell Extract on Ultraviolet B-Irradiated Melanocytes

Ultraviolet (UV) radiation generates a range of biological effects in the skin, which includes premature skin aging, hyperpigmentation, and cancer. Therefore, the development of new effective agents for UV-related skin damage remains a challenge in the pharmaceutical industry. This study aims to test the inhibitory effect of crocodile white blood cell (cWBC) extract, a rich source of bioactive peptides, on ultraviolet B (UVB)-induced melanocyte pigmentation. The results showed that cWBC (6.25-400 μg/mL) could inhibit tyrosinase without adduct formation by 12.97 ± 4.20% on average. cWBC pretreatment (25-100 μg/mL) had no cytotoxicity and reduced intracellular melanin to 111.17 ± 5.20% compared with 124.87 ± 7.43 for UVB condition. The protective role of cWBC pretreatment against UVB was exhibited by the promotion of cell proliferation and the prevention of UVB-induced morphological change as observed from F actin staining. The decrease of microphthalmia-associated transcription factor expression levels after cWBC pretreatment might be a mechanism by which cWBC suppresses UVB-induced pigmentation. These results suggest that cWBC could be beneficial for the prevention of UVB-induced skin pigmentation.

Neuroprotective Effects against Glutamate-Induced HT-22 Hippocampal Cell Damage and Caenorhabditis elegans Lifespan/Healthspan Enhancing Activity of Auricularia polytricha Mushroom Extracts

Oxidative stress is associated with several diseases, particularly neurodegenerative diseases, commonly found in the elderly. The attenuation of oxidative status is one of the alternatives for neuroprotection and anti-aging. Auricularia polytricha (AP), an edible mushroom, contains many therapeutic properties, including antioxidant properties. Herein, we report the effects of AP extracts on antioxidant, neuroprotective, and anti-aging activities. The neuroprotective effect of AP extracts against glutamate-induced HT-22 neuronal damage was determined by evaluating the cytotoxicity, intracellular reactive oxygen species (ROS) accumulation, and expression of antioxidant enzyme genes. Lifespan and healthspan assays were performed to examine the effects of AP extracts from Caenorhabditis elegans. We found that ethanolic extract (APE) attenuated glutamate-induced HT-22 cytotoxicity and increased the expression of antioxidant enzyme genes. Moreover, APE promoted in the longevity and health of the C. elegans. Chemical analysis of the extracts revealed that APE contains the highest quantity of flavonoids and a reasonable percentage of phenols. The lipophilic compounds in APE were identified by gas chromatography/mass spectrometry (GC/MS), revealing that APE mainly contains linoleic acid. Interestingly, linoleic acid suppressed neuronal toxicity and ROS accumulation from glutamate induction. These results indicate that AP could be an exciting natural source that may potentially serves as neuroprotective and anti-aging agents.

Bioactive Phytochemical Constituents of Wild Edible Mushrooms from Southeast Asia

Mushrooms have a long history of uses for their medicinal and nutritional properties. They have been consumed by people for thousands of years. Edible mushrooms are collected in the wild or cultivated worldwide. Recently, mushroom extracts and their secondary metabolites have acquired considerable attention due to their biological effects, which include antioxidant, antimicrobial, anti-cancer, anti-inflammatory, anti-obesity, and immunomodulatory activities. Thus, in addition to phytochemists, nutritionists and consumers are now deeply interested in the phytochemical constituents of mushrooms, which provide beneficial effects to humans in terms of health promotion and reduction of disease-related risks. In recent years, scientific reports on the nutritional, phytochemical and pharmacological properties of mushroom have been overwhelming. However, the bioactive compounds and biological properties of wild edible mushrooms growing in Southeast Asian countries have been rarely described. In this review, the bioactive compounds isolated from 25 selected wild edible mushrooms growing in Southeast Asia have been reviewed, together with their biological activities. Phytoconstituents with antioxidant and antimicrobial activities have been highlighted. Several evidences indicate that mushrooms are good sources for natural antioxidants and antimicrobial agents.

Antioxidant and anti-tumour activity of triterpenoid compounds isolated from Morchella mycelium

Triterpenoid compounds are important bioactivity materials. Morchella is an abundant medicinal fungi found worldwide. In this study, we optimised the isolation and purification of triterpenoid compounds from Morchella mycelium fermentation. The results showed that the triterpenoid compounds yield was 35.22 mg/g, and we also identified two triterpenoid compounds using high-performance liquid chromatography. In addition, we evaluated the anti-tumour and antioxidant activity of the products, and the results showed that triterpenoid compounds from Morchella mycelium fermentation showed good bioactivity. The IC₅₀ values of four cancer cell lines treated with the triterpenoid compounds for 48 h were 7.20, 14.96, 4.41, and 13.43 mg/mL, respectively. Morphological changes associated with the apoptosis of PC-3 cells were observed using confocal scanning laser microscopy after treatment with triterpenoid compounds for 48 and 72 h. The triterpenoid compounds also exhibited DPPH radical, hydroxyl, and ABTS-free radical scavenging activities in vitro. These results suggest that triterpenoid compounds from Morchella mycelium fermentation, which are found in functional foods and used in the field of pharmacology, might be excellent products for the treatment of cancer and age-related illnesses.

The Role of Bioactive Compounds and other Metabolites from Mushrooms against Skin Disorders- A Systematic Review Assessing their Cosmeceutical and Nutricosmetic Outcomes

Bioactive compounds derived from mushrooms have been shown to present promising potential as cosmeceutical or nutricosmetic ingredients. Scientific data reviewed herein showed that extracts prepared from medicinal and edible mushrooms and their individual metabolites presented antiinflammatory, antioxidant, photoprotective, antimicrobial, anti-tyrosinase, anti-elastase, and anticollagenase activities. These metabolites can be utilised as ingredients to suppress the severity of Inflammatory Skin Diseases, offer photoprotection to the skin, and correct Hyperpigmentation. However, studies regarding the molecular mechanism behind the mentioned bioactivities are still lacking. Challenges associated with the use of mushroom extracts and their associated metabolites as cosmeceutical and nutricosmetic ingredients include several steps from the fruiting bodies to the final product: extraction optimization, estimation of the efficacy and safety claims, the use of micro and nanocarriers to allow for controlled release and the pros and cons associated with the use of extracts vs individual compounds. This systematic review highlights that mushrooms contain diverse biomolecules that can be sustainably used in the development of nutricosmetic and cosmeceutical formulations. Reports regarding stability, compatibility, and safety assessment, but also toxicological studies are still needed to be considered. Furthermore, some of the constraints and limitations hindering the development of this type of ingredients still require long-term studies to achieve major breakthroughs.

Anti-HIV-1 protease activity of the crude extracts and isolated compounds from Auricularia polytricha

BACKGROUND

Acquired immunodeficiency syndrome (AIDS) is caused by the Human immunodeficiency virus type-1 (HIV-1). HIV-1 protease (HIV-1 PR) is an essential enzyme for the HIV replication, and therefore, it is an important target for antiretroviral drugs development, particularly from natural products. Auricularia polytricha (AP) is an edible mushroom with several important therapeutic properties. These properties will be investigated as HIV-1 PR inhibitors.

METHODS

The sequential hexane (APH), ethanol (APE) and water (APW) extracts from AP were screened for inhibitory activity against HIV-1 PR. The extract that consistently showed the strong HIV-1 PR inhibition was further investigated for its phytochemical constituents. The compounds were purified by column chromatography. The isolated compounds were structurally elucidated using 1D and 2D NMR, HRMS, FTIR, and GC/MS techniques. Each compound was screened against HIV-1 PR to determine its inhibitory activity and to provide an explanation for the activity found in the extract.

RESULTS

Hexane crude extract of AP (APH) exhibited significant inhibition on HIV-1 PR activity. Four major compounds isolated from APH fraction were identified to be two triacylglycerols, linoleic acid and ergosterol. Moreover, all four compounds showed significant inhibition of HIV-1 PR activity.

CONCLUSION

The findings from this study suggest that AP is a good source of fatty esters, fatty acids and ergosterol. These natural products exhibit anti-HIV-1 properties by blocking HIV-1 PR. These important biological results warrant further development of AP as an alternative antiretroviral drug.

First demonstration of protective effects of purified mushroom polysaccharide-peptides against fatty liver injury and the mechanisms involved

Fatty liver (FLD) disease is a consequence of metabolic syndrome, which is a health problem worldwide with a phenomenal rise in prevalence. In this study, two hepatoprotective polysaccharide-peptides were extracted from the mushroom Auricularia polytricha followed by chromatographic fractionation of the extract on the ion exchanger DEAE-cellulose and gel filtration on Sephadex-200 to yield two purified fractions: APPI and APPII. The monosaccharide compositions, FT-IR, N-terminal sequences, internal peptide sequences and molecular weights of the two fractions were determined. Furthermore, their hepatoprotective effect on human hepatoma HepG2 cells in vitro and in an animal model of fatty liver disease was evidenced by the findings that APPI and APPII diminished lipid deposit in cells, blood and the liver, increased cellular antioxidant activity and viability, and protected the liver against injury. The mechanistic study revealed that APPI and APPII activated the adiponectin pathway, up-regulated expression of genes controlling free fatty acid (FFA) oxidation, such as AMPK, CPTl, ACOX1 and PPARα genes, enhanced lipid metabolism, preserved hepatic function, promoted the antioxidant defense system and reduced lipid peroxidation. Hence the bioactive compounds of A. polytricha could serve as therapeutic agents in the food and pharmaceutical industries.

Anti-Melanogenic Effect from Submerged Mycelial Cultures of Ganoderma weberianum

Compounds from Lingzhi has been demonstrated the ability for inhibiting tyrosinase (a key enzyme in melanogenesis) activity. In this study, we investigated the anti-melanogenic activity from the submerged mycelial culture of Ganoderma weberianum and elucidated the skin lightening mechanism by B16-F10 murine melanoma cells. From the cellular context, several fractionated mycelium samples exhibited anti-melanogenic activity by reducing more than 40% extracellular melanin content of B16-F10 melanoma cells. In particular, the fractionated chloroform extract (CF-F3) inhibited both secreted and intracellular melanin with the lowest dosage (25 ppm). Further analysis demonstrated that CF-F3 inhibited cellular tyrosinase activity without altering its protein expression. Taken together, our study has demonstrated that the chemical extracts from submerged mycelial culture of G. weberianum have the potential to serve as an alternative anti-melanogenic agent.

Determination of the volatile and polyphenol constituents and the antimicrobial, antioxidant, and tyrosinase inhibitory activities of the bioactive compounds from the by-product of Rosa rugosa Thunb. var. plena Regal tea

Background

The phytochemical constituents and biological activities of Rosa rugosa Thunb. var. plena Regal flower cell sap (RFCS) were investigated.

Methods

Volatile constituent, such as linalool, phenylethyl alcohol, citronellol, α-bisabolol, were identified by GC-MS. The contents of hyperoside, kaempferol-3-O-rutinosid, rutin, and luteolin as well as the total flavonoid content in RFCS were determined by HPLC and HPLC-MS. The total polyphenol content was evaluated by the Folin-Ciocalteu colorimetric method. The antioxidant activities of RFCS and the standards were evaluated by DPPH and ABTS radical scavenging assays. The tyrosinase inhibitory activities of the rose samples and standard substance were determined by a spectrophotometric method. The antimicrobial effects of RFCS were evaluated in terms of minimum inhibitory concentrations (MICs) and minimum bactericidal concentrations (MBCs) or minimum Fungicidal concentrations (MFCs).

Results

The rose fraction exhibited a high content of biologically active ingredients. The total content of volatile compounds in RFCS was approximately 48.21 ± 2.76 ng/mL. The total phenolic acid content and total flavonoid content were 0.31 ± 0.01 mg/mL and 0.43 ± 0.01 mg/mL, respectively. Its IC₅₀ value in the DPPH assay was 1120 ± 42 μg/mL, and its IC₅₀ value for ABTS radical scavenging activity was 1430 ± 42 μg/mL.RFCS strongly inhibited L-tyrosine oxidation with an IC₅₀ value of 570 ± 21 μg/mL. Every compound identified in RFCS exhibited broad-spectrum antimicrobial activity. F. nucleatum was most susceptible to RFCS with an MIC of 64 μg/mL and MBC of 250 μg/mL.

Conclusions

Due to its rose-like aroma, phenylethyl alcohol may be combined with linalool for use as a natural skin-whitening agent and skin care additive in the and pharmaceutical industries.

Effects of element complexes containing Fe, Zn and Mn on artificial morel's biological characteristics and soil bacterial community structures

This study described the effects of elements (including Fe, Zn, Mn and their complexes) on the following factors in artificial morel cultivation: the characteristics of mycelia and sclerotia, soil bacterial community structures, yields and contents of microelements. The results indicated that the groups containing Mn significantly promoted mycelia growth rates, and all the experimental groups resulted in higher yields than the control (P<0.01), although their mycelia and sclerotia did not show obvious differences. It was also found that Proteobacteria, Chloroflexi, Bacteroides, Firmicutes, Actinobacteria, Acidobacteria and Nitrospirae were the dominated bacterial phyla. The Zn·Fe group had an unexpectedly high proportion (75.49%) of Proteobacteria during the primordial differentiation stage, while Pseudomonas also occupied a high proportion (5.52%) in this group. These results suggested that different trace elements clearly affected morel yields and soil bacterial community structures, particularly due to the high proportions of Pseudomonas during the primordial differentiation stage.