Antimicrobial and antioxidant activities and effect of 1-hexadecene addition on palmarumycin C2 and C3 yields in liquid culture of endophytic fungus Berkleasmium sp. Dzf12

Evaluation of anti-inflammatory and wound healing properties of Tinospora cordifolia extract

Tinospora cordifolia extract exhibits diverse benefits-anti-arthritis, anti-malarial, anti-allergic, anti-diabetic, antihepatotoxic, and antipyretic effects. Its specific anti-inflammatory and healing capacities remain unexplored, prompting a study utilizing a mouse skin wound model and direct T. cordifolia extraction. UV-Vis spectroscopy depicted an absorption range of 200-400 nm, while FTIR analysis identified alcohols, phenols, amines, amides, aldehydes, ketones, alkanes, and alkenes. GC-MS analysis revealed the presence of components: 5methyl-5-Hexen-2-Ol, n-hexadecenoic acid, cholesta-4,6-dien-3beta-ol, stigmasterol, β-sitosterol, stearate which are present in the extract. Histopathological examination confirmed accelerated wound healing, showcasing reduced inflammation, restored blood vessels, collagen fibers, and swift epidermal closure. T. cordifolia extract exhibits promise in enhancing wound healing through its antibacterial, anti-inflammatory properties.

Highly Functionalized Spirobisnaphthalenes from Roussoella sp. KT4147

Highly functionalized spirobisnaphthalenes, preussomerins N (1) and O (2), and simpler compounds, such as 2,3-α-epoxypalmarumycin CP18 (3), 3α-hydroxy-CJ-12,372 (4), and 16 known structurally related congeners, were isolated from a culture broth of Roussoella sp. KT4147. Structural analysis revealed that 1 was a dimer of preussomerin G (6), connected by a nitrogen atom, and 2 was a derivative of 6 with a macommelin substructure. Preussomerin N (1) was considered to be biosynthetically derived via the Michael-type 1,4-addition of ammonia to 6, followed by another Michael addition to another molecule of 6. Contrarily, 2 was suggested to be derived through an endo-Diels-Alder cycloaddition between a diene derived from the (E)-enol form of macommelinal via an ene-reaction and dienophile 6. Compounds 1 and 2 exhibited potent cytotoxicity against COLO-201 human colorectal cancer cells.

Elucidation of Palmarumycin Spirobisnaphthalene Biosynthesis Reveals a Set of Previously Unrecognized Oxidases and Reductases

Spirobisnaphthalenes (SBNs) are a class of highly oxygenated, fungal bisnaphthalenes containing a unique spiroketal bridge, that displayed diverse bioactivities. Among the reported SBNs, palmarumycins are the major type, which are precursors for the other type of SBNs structurally. However, the biosynthesis of SBNs is unclear. In this study, we elucidated the biosynthesis of palmarumycins, using gene disruption, heterologous expression, and substrate feeding experiments. The biosynthetic gene cluster for palmarumycins was identified to be distant from the polyketide synthase gene cluster, and included two cytochrome P450s (PalA and PalB), and one short chain dehydrogenase/reductase (PalC) encoding genes as key structural genes. PalA is an unusual, multifunctional P450 that catalyzes the oxidative dimerization of 1,8-dihydroxynaphthalene to generate the spiroketal linkage and 2,3-epoxy group. Chemical synthesis of key intermediate and in vitro biochemical assays proved that the oxidative dimerization proceeded via a binaphthyl ether. PalB installs the C-5 hydroxy group, widely found in SBNs. PalC catalyzes 1-keto reduction, the reverse 1-dehydrogenation, and 2,3-epoxide reduction. Moreover, an FAD-dependent oxidoreductase, encoded by palD, which locates outside the cluster, functions as a 1-dehydrogenase. These results provided the first genetic and biochemical evidence for the biosynthesis of palmarumycin SBNs.

Efficient gene editing in the slow-growing, non-sporulating, melanized, endophytic fungus Berkleasmium sp. Dzf12 using a CRISPR/Cas9 system

The endophytic fungus Berkleasmium sp. Dzf12 that was isolated from Dioscorea zingiberensis, is a proficient producer of palmarumycins, which are intriguing polyketides of the spirobisnaphthalene class. These compounds displayed a wide range of bioactivities, including antibacterial, antifungal, and cytotoxic activities. However, conventional genetic manipulation of Berkleasmium sp. Dzf12 is difficult and inefficient, partially due to the slow-growing, non-sporulating, and highly pigmented behavior of this fungus. Herein, we developed a CRISPR/Cas9 system suitable for gene editing in Berkleasmium sp. Dzf12. The protoplast preparation was optimized, and the expression of Cas9 in Berkleasmium sp. Dzf12 was validated. To assess the gene disruption efficiency, a putative 1, 3, 6, 8-tetrahydroxynaphthalene synthase encoding gene, bdpks, involved in 1,8-dihydroxynaphthalene (DHN)-melanin biosynthesis, was selected as the target for gene disruption. Various endogenous sgRNA promoters were tested, and different strategies to express sgRNA were compared, resulting in the construction of an optimal system using the U6 snRNA-1 promoter as the sgRNA promoter. Successful disruption of bdpks led to a complete abolishment of the production of spirobisnaphthalenes and melanin. This work establishes a useful gene targeting disruption system for exploration of gene functions in Berkleasmium sp. Dzf12, and also provides an example for developing an efficient CRISPR/Cas9 system to the fungi that are difficult to manipulate using conventional genetic tools.

In-silico and in-vitro evaluation of antifungal bioactive compounds from Streptomyces sp. strain 130 against Aspergillus flavus

Streptomyces spp. are considered excellent reservoirs of natural bioactive compounds. The study evaluated the bioactive potential of secondary metabolites from Streptomyces sp. strain 130 through PKS-I and NRPS gene-clusters screening. GC-MS analysis was done for metabolic profiling of bioactive compounds from strain 130 in the next set of experiments. Identified antifungal compounds underwent ADMET analyses to screen their toxicity. All compounds' molecular docking was done with the structural gene products of the aflatoxin biosynthetic pathway of Aspergillus flavus. MD simulations were utilized to evaluate the stability of protein-ligand complexes under physiological conditions. Based on the in-silico studies, compound 2,4-di-tert butyl-phenol (DTBP) was selected for in-vitro studies against Aspergillus flavus. Simultaneously, bioactive compounds were extracted from strain 130 in two different solvents (ethyl-acetate and methanol) and used for similar assays. The MIC value of DTBP was found to be 314 µg/mL, whereas in ethyl-acetate extract and methanol-extract, it was 250 and 350 µg/mL, respectively. A mycelium growth assay was done to analyze the effect of compounds/extracts on the mycelium formation of Aspergillus flavus. In agar diffusion assay, zone of inhibitions in DTBP, ethyl-acetate extract, and methanol extract were observed with diameters of 11.3, 13.3, and 7.6 mm, respectively. In the growth curve assay, treated samples have delayed the growth of fungi, which signified that the compounds have a fungistatic nature. Spot assay has determined the fungal sensitivity to a sub-minimum inhibitory concentration of antifungal compounds. The study's results suggested that DTBP can be exploited for antifungal-drug development.

Identification of natural CTXM-15 inhibitors from aqueous extract of endophytic bacteria Cronobactersakazaki

Nyctanthes arbor-tristis is one of India's valuable and populous medicinal plants which belongs to the family Oleaceae, and widely recognize as night jasmine. Over the years till date, different parts of the plant are used to treat or cure different ailments via various means of traditional medicine. Endophytes are organisms that live in the cell or body of other organisms with no apparent negative impact on the host which they inhabit and are of great source of novel bioactive compounds possessing important economic value. Secondary metabolites were identified in the aqueous extract of Cronobactersakazakii through quantitative phytochemical and GC-MS analysis. Antibacterial activity of the extract against clinical and ATCC strains of E. coli was assessed. Biological activity spectra of these compounds were predicted and categorized either as probably active (Pa) or probably inactive (Pi). Drug-likeness of bioactive compounds was determined as well as their ability to target protein (CTXM-15) responsible for antibiotic resistance in Gram-negative bacteria. Results revealed the presence of active compounds with pharmacological activities and considerable pharmacokinetics parameters. In addition, ligand-protein interactions of compounds with CTXM-15 proteins were identified. These results suggest that bioactive compounds of endophytic Cronobactersakazakii could contain novel chemical entities for the development of antibiotics against pathogenic microbes and other drugs for the amelioration of several infections.

Synergistic Effect of Diet and Physical Activity on a NAFLD Cohort: Metabolomics Profile and Clinical Variable Evaluation

Together with its comorbidities, nonalcoholic fatty liver disease (NAFLD) is likely to rise further with the obesity epidemic. However, the literature's evidence shows how its progression can be reduced by the administration of calorie-restrictive dietary interventions and physical activity regimens. The liver function and the gut microbiota have been demonstrated to be closely related. With the aim of ascertaining the impact of a treatment based on the combination of diet and physical activity (versus physical activity alone), we recruited 46 NAFLD patients who were divided into two groups. As a result, we traced the connection between volatile organic compounds (VOCs) from fecal metabolomics and a set of statistically filtered clinical variables. Additionally, we identified the relative abundances of gut microbiota taxa obtained from 16S rRNA gene sequencing. Statistically significant correlations emerged between VOCs and clinical parameters, as well as between VOCs and gut microbiota taxa. In comparison with a physical activity regimen alone, we disclose how ethyl valerate and pentanoic acid butyl ester, methyl valerate, and 5-hepten-2-one, 6-methyl changed because of the positive synergistic effect exerted by the combination of the Mediterranean diet and physical activity regimens. Moreover, 5-hepten-2-one, 6-methyl positively correlated with Sanguinobacteroides, as well as the two genera Oscillospiraceae-UCG002 and Ruminococcaceae UCG010 genera.

Osteogenic Potential and Bioactive Profiles of Piper sarmentosum Ethanolic Extract-Treated Stem Cells

Piper sarmentosum is a well-known traditional herbal plant in various diseases treatments. Multiple scientific studies have also reported various biological activities exhibited by the plant's extract, such as antimicrobial, anticarcinogenic and antihyperglycemic activities, and, in addition, a bone protective effect in ovariectomized rats has been reported. However, no known Piper sarmentosum extract is involved in osteoblast differentiation using stem cells. Our study aims to identify the potential of P. sarmentosum ethanolic extract to induce osteoblast differentiation of human peripheral blood stem cells. Prior to the assay, the proliferation ability of the cells was observed for 14 days and the presence of hematopoietic stem cells in the culture was determined by the expression of SLAMF1 and CD34 genes. During the differentiation assay, the cells were treated with P. sarmentosum ethanolic extract for 14 days. Osteoblast differentiation was examined using an (alkaline phosphatase) ALP assay, by monitoring the expression of osteogenic gene markers and by von Kossa staining. The untreated cells served as the negative control, while cells treated with 50 µg/mL ascorbic acid and 10 mM β-glycerophosphate acted as the positive control. Finally, the determination of the compound profile was performed using a gas chromatography-mass spectrometry (GC-MS) analysis. The isolated cells were able to proliferate for 14 days during the proliferation assay. The expression of hematopoietic stem cell markers was also upregulated during the 14 days assay. Following the differentiation induction, the ALP activity exhibited a significant increase (p < 0.05) from day 3 of the differentiation assay. A molecular analysis also showed that the osteogenic markers ALP, RUNX2, OPN and OCN were upregulated compared to the positive control. The presence of mineralized cells with a brownish-stained morphology was observed, indicating the mineralization process increased in a time-dependent manner regardless of the concentration used. There were 54 compounds observed in the GC-MS analysis, including β-asarones, carvacrol and phytol, which have been shown to possess osteoinductive capacities. Our results demonstrate that the ethanolic extract of P. sarmentosum can induce osteoblast differentiation of peripheral blood stem cells. The extract contains potent compounds which can potentially induce the differentiation of bone cells, i.e., osteoblasts.

“Metabolomic diversity of local strains of Beauveria bassiana (Balsamo) Vuillemin and their efficacy against the cassava mite, Tetranychus truncatus Ehara (Acari: Tetranychidae)”

A desirable substitute for chemical pesticides is mycopesticides. In the current investigation, rDNA-ITS (Internal transcribed spacer) and TEF (Transcriptional Elongation Factor) sequencing were used for molecular identification of six Beauveria bassiana strains. Both, leaf discs and potted plant bioassaye were carried out to study their pathogenicity against the cassava mite, Tetranychus truncatus. LC₅₀ and LC₉₀ values of potential B. bassiana strains were estimated. We also discovered a correlation between intraspecific B. bassiana strains pathogenicity and comprehensive metabolome profiles. Bb5, Bb6, Bb8, Bb12, Bb15, and Bb21 strains were identified as B. bassiana by sequencing of rDNA-ITS and TEF segments and sequence comparison to NCBI (National Center for Biotechnology Information) GenBank. Out of the six strains tested for pathogenicity, Bb6, Bb12, and Bb15 strains outperformed against T. truncatus with LC₅₀ values 1.4×10⁶, 1.7×10⁶, and 1.4×10⁶ and with a LC₉₀ values 7.3×10⁷, 1.4×10⁸, and 4.2×10⁸ conidia/ml, respectively, at 3 days after inoculation and were considered as potential strains for effective mite control. Later, Gas Chromatography-Mass Spectrometry (GC-MS) analysis of the above six B. bassiana strains was done on secondary metabolites extracted with ethyl acetate revealed that the potential B. bassiana strains (Bb6, Bb12, and Bb15) have higher levels of acaricidal such as Bis(dimethylethyl)-phenol: Bb6 (5.79%), Bb12 (6.15%), and Bb15 (4.69%). Besides, insecticidal (n-Hexadecanoic acid), and insect innate immunity overcoming compound (Nonadecene) were also identified; therefore, the synergistic effect of these compounds might lead toa higher pathogenicity of B. bassiana against T. truncatus. Further, these compounds also exhibited two clusters, which separate the potential and non-potential strains in the dendrogram of Thin Layer Chromatography. These results clearly demonstrated the potentiality of the B. bassiana strains against T. truncatus due to the occurrence of their bioactive volatile metabolome.

The antimicrobial, antibiofilm, and wound healing properties of ethyl acetate crude extract of an endophytic fungus Paecilomyces sp. (AUMC 15510) in earthworm model

The endophytic fungus Paecilomyces sp. (AUMC 15510) was isolated from healthy stem samples of the Egyptian medicinal plant Cornulaca monacantha. We used GC-MS and HPLC analysis to identify the bioactive constituents of ethyl acetate crude extract of Paecilomyces sp. (PsEAE). Six human microbial pathogens have been selected to evaluate the antimicrobial activity of PsEAE. Our data showed that the extract has significant antimicrobial activity against all tested pathogens. However, the best inhibitory effect was observed against Bacillus subtilis ATCC 6633 and Pseudomonas aeruginosa ATCC 90274 with a minimum inhibitory concentration (MIC) of 3.9 μg/ml and minimum bactericidal concentration (MBC) of 15.6 μg/ml, for both pathogens. Also, PsEAE exerts a significant inhibition on the biofilm formation of the previously mentioned pathogenic strains. In addition, we evaluated the wound healing efficiency of PsEAE on earthworms (Lumbricus castaneus) as a feasible and plausible model that mimics human skin. Interestingly, PsEAE exhibited a promising wound healing activity and enhanced wound closure. In conclusion, Paecilomyces sp. (AUMC 15510) could be a sustainable source of antimicrobial agents and a potential therapeutic target for wound management.

Pharmacological activities and gas chromatography-mass spectrometry analysis for the identification of bioactive compounds from Justicia adhatoda L

The current study aimed to assess the pharmacological potential of Justicia adhatoda by evaluating the presence of biologically active compounds using the gas chromatography-mass spectrometry approach and to undertake biological activities for the effectiveness of the present compounds using standard tests. A total of 21 compounds were identified in the gas chromatography-mass spectrometry analysis of the ethyl acetate fraction in which 14 of the identified compounds are recognized for their pharmacological potential in the literature. In total, four fractions (ethyl acetate, chloroform, n-hexane, and aqueous) were evaluated for pharmacological activities. In carrageenan-induced inflammation, the chloroform fraction exhibited high anti-inflammatory activity (46.51%). Similarly, the analgesic potential of ethyl acetate fraction was the most effective (300 mg/kg) in the acetic acid-induced test. Similarly, in the formalin test, ethyl acetate fraction exhibited maximum inhibition in both early (74.35%) and late phases (88.38). Maximum inhibition of pyrexia (77.98%) was recorded for the ethyl acetate fraction (300 mg/kg). In DPPH assay, the ethyl acetate fraction revealed the highest scavenging potential among other fractions (50 μg/ml resulted in 50.40% and 100 μg/ml resulted in 66.74% scavenging).

Phytochemical Profiling, Antioxidant, Anti-Inflammatory, Thrombolytic, Hemolytic Activity In Vitro and In Silico Potential of Portulacaria afra

The use of complementary herbal medicines has recently increased in an attempt to find effective alternative therapies that reduce the adverse effects of chemical drugs. Portulacaria afra is a rich source of phytochemicals with high antioxidant activity, and thus may possess health benefits. This study used the latest developments in GC-MS coupling with molecular docking techniques to identify and quantify the phytoconstituents in P. afra tissue extracts. The results revealed that n-butanol P. afra (BUT-PA) dry extracts contained total phenolic and flavonoids contents of 21.69 ± 0.28 mgGAE/g and 196.58 ± 6.29 mgGAE/g, respectively. The significant potential of antioxidants was observed through CUPRIC, FRAP, and ABTS methods while the DPPH method showed a moderate antioxidants potential for P. afra. Enzymatic antioxidants, superoxide dismutase, peroxidase and catalase also showed a better response in the BUT-PA dry extracts. The thrombolytic activity of the BUT-PA extracts ranged from 0.4 ± 0.32 to 11.2 ± 0.05%. Similarly, hemolytic activity ranged from 5.76 ± 0.15 to 9.26 ± 0.15% using the standard (triton x) method. The BUTPA and CHPA showed moderate acetylcholinesterase and butrylcholinesterase inhibition, ranging from 40.78 ± 0.52 to 58.97 ± 0.33, compared to galantamine. The carrageenan induced hind-paw edema assay, while BUT-PA extracts showed anti-inflammatory properties in a dose-dependent manner. Furthermore, 20 compounds were identified in the BUTPA extracts by GC-MS. Molecular docking was performed to explore the synergistic effect of the GC-MS-identified compounds on COX-1 and COX-2 inhibition. A high binding affinity was observed for Stigmastan-3, 5-diene, Phthalic acid, 3. Alpha-Hydroxy-5, 16-androstenol. The computed binding energies of the compounds revealed that all the compounds have a synergistic effect, preventing inflammation. It was concluded that active phytochemicals were present in P. afra, with the potential for multiple pharmacological applications as a latent source of pharmaceutically important compounds. This should be further explored to isolate secondary metabolites that can be employed in the treatment of different diseases.

Phytochemical Profiling, In Vitro Biological Activities, and In Silico Molecular Docking Studies of Dracaena reflexa

Dracaena reflexa, a traditionally significant medicinal plant, has not been extensively explored before for its phytochemical and biological potential. The present study was conducted to evaluate the bioactive phytochemicals and in vitro biological activities of D. reflexa, and perform in silico molecular docking validation of D. reflexa. The bioactive phytochemicals were assessed by preliminary phytochemical testing, total bioactive contents, and GC-MS analysis. For biological evaluation, the antioxidant (DPPH, ABTS, CUPRAC, and ABTS), antibacterial, thrombolytic, and enzyme inhibition (tyrosinase and cholinesterase enzymes) potential were determined. The highest level of total phenolic contents (92.72 ± 0.79 mg GAE/g extract) was found in the n-butanol fraction while the maximum total flavonoid content (110 ± 0.83 mg QE/g extract) was observed in methanolic extract. The results showed that n-butanol fraction exhibited very significant tyrosinase inhibition activity (73.46 ± 0.80) and acetylcholinesterase inhibition activity (64.06 ± 2.65%) as compared to other fractions and comparable to the standard compounds (kojic acid and galantamine). The methanolic extract was considered to have moderate butyrylcholinesterase inhibition activity (50.97 ± 063) as compared to the standard compound galantamine (53.671 ± 0.97%). The GC-MS analysis of the n-hexane fraction resulted in the tentative identification of 120 bioactive phytochemicals. Furthermore, the major compounds as identified by GC-MS were analyzed using in silico molecular docking studies to determine the binding affinity between the ligands and the enzymes (tyrosinase, acetylcholinesterase, and butyrylcholinesterase enzymes). The results of this study suggest that Dracaena reflexa has unquestionable pharmaceutical importance and it should be further explored for the isolation of secondary metabolites that can be employed for the treatment of different diseases.

Comparative Profiling of Volatile Compounds in Popular South Indian Traditional and Modern Rice Varieties by Gas Chromatography-Mass Spectrometry Analysis

Rice (Oryza sativa L.) is one of the major cereal crops cultivated across the world, particularly in Southeast Asia with 95% of global production. The present study was aimed to evaluate the total phenolic content (TPC) and to profile all the volatile organic compounds (VOCs) of eight popular traditional and two modern rice varieties cultivated in South India. Thirty-one VOCs were estimated by gas chromatography–mass spectrometry (GC-MS). The identified volatile compounds in the 10 rice varieties belong to the chemical classes of fatty acids, terpenes, alkanes, alkenes, alcohols, phenols, esters, amides, and others. Interestingly, most of the identified predominant components were not identical, which indicate the latent variation among the rice varieties. Significant variations exist for fatty acids (46.9–76.2%), total terpenes (12.6–30.7%), total phenols (0.9–10.0%), total aliphatic alcohols (0.8–5.9%), total alkanes (0.5–5.1%), and total alkenes (1.0–4.9%) among the rice varieties. Of all the fatty acid compounds, palmitic acid, elaidic acid, linoleic acid, and oleic acid predominantly varied in the range of 11.1–33.7, 6.1–31.1, 6.0–28.0, and 0.7–15.1%, respectively. The modern varieties recorded the highest palmitic acid contents (28.7–33.7%) than the traditional varieties (11.1–20.6%). However, all the traditional varieties had higher linoleic acid (10.0–28.0%) than the modern varieties (6.0–8.5%). Traditional varieties had key phenolic compounds, stearic acid, butyric acid, and glycidyl oleate, which are absent in the modern varieties. The traditional varieties Seeraga samba and Kichilli samba had the highest azulene and oleic acid, respectively. All these indicate the higher variability for nutrients and aroma in traditional varieties. These varieties can be used as potential parents to improve the largely cultivated high-yielding varieties for the evolving nutritional market. The hierarchical cluster analysis showed three different clusters implying the distinctness of the traditional and modern varieties. This study provided a comprehensive volatile profile of traditional and modern rice as a staple food for energy as well as for aroma with nutrition.

Terrestrial Microorganisms: Cell Factories of Bioactive Molecules with Skin Protecting Applications

It is well known that terrestrial environments host an immense microbial biodiversity. Exposed to different types of stress, such as UV radiation, temperature fluctuations, water availability and the inter- / intra-specific competition for resources, terrestrial microorganisms have been evolved to produce a large spectrum of bioactive molecules. Bacteria, archaea, protists, fungi and algae have shown a high potential of producing biomolecules for pharmaceutical or other industrial purposes as they combine a sustainable, relatively low-cost and fast-production process. Herein, we provide an overview of the different bioactive molecules produced by terrestrial microorganisms with skin protecting applications. The high content in polyphenolic and carotenoid compounds produced by several strains, as well as the presence of exopolysaccharides, melanins, indole and pyrrole derivatives, mycosporines, carboxylic acids and other molecules, are discussed in the context of their antioxidant, photo-protective and skin-whitening activity. Relevant biotechnological tools developed for the enhanced production of high added value natural products, as well as the protecting effect of some antioxidant, hydrolytic and degrading enzymes are also discussed. Furthermore, we describe classes of microbial compounds that are used or have the potential to be used as antimicrobials, moisturizers, biosurfactants, pigments, flavorings and fragrances.

Comparison of the Proximate Composition, Vitamins (Ascorbic Acid, α-Tocopherol and Retinol), Anti-Nutrients (Phytate and Oxalate) and the GC-MS Analysis of the Essential Oil of the Root and Leaf of Rumex crispus L

Medicinal plants are a pertinent and effective remedy, employed in indigenous healthcare systems by traditional healers. This study focused on proximate parameters, minerals, vitamins, anti-nutrients and essential oil of the root and leaf of the medicinal plant; R. crispus, using the standard food analysis techniques. The result reveals that the moisture content of the leaf (7.57 ± 0.40%) and root (7.59 ± 0.08%) was not significantly different. The leaf has a higher ash, crude fat, fibre and mineral content than the root, except the carbohydrate (57.74 ± 3.06%) and Ca (1190.0 ± 0 mg/100g) values which are quite higher in the root. Traces of phytate was found in the leaf (1.15 ± 0.74%) and root (1.38 ± 0.27%) of R. crispus. The highest value of retinol, ascorbic acid and α-tocopherol was found in dried leaf (1.29 ± 0.014 mg retinol/100g), fresh leaf (159.73 ± 26.77 mg ascorbic acid/100g) and fresh root (54.90 ± 0.39 mg α-tocopherol/100g) respectively. The principal compound in the essential oil of the leaf are; 5-Eicosene, (E)-, docos-1-ene, trans-5-Octadecene, tetradecane while those found in the root are; 1-Heptacosanol, 4-Methyloctane, ethylcyclohexane, eucalyptol, m-Xylene, octadecane, phytol, and tetradecane. The research reveals that R. crispus may not only be used for medicinal purposes but could also be suitable for a complementary diet.

Optimization of the Antioxidant Potentials of Red Pitaya Peels and Its In Vitro Skin Whitening Properties

In this study, response surface methodology (RSM) was employed for the optimization of the antioxidant potentials of red pitaya peels using independent variables: temperature (45–65 °C), ethanol concentration (70–90%, v/v) and time (80–120 min) through its responses, which were DPPH scavenging activity, ferric ion reducing antioxidant power (FRAP), and beta-carotene bleaching (BCB) inhibition, respectively. In Vitro anti-tyrosinase and vitamin C content assays were carried out spectrophotometrically to determine the skin whitening efficacy of the optimized red pitaya peel extract. A gas chromatography-mass spectrometry (GC-MS) analysis was employed to identify the chemical constituents present in the optimized extract. The optimized conditions were ethanol 82% (v/v) for 103 min at 56 °C with values of 75.98% for DPPH, 7.45 mM Fe2+/g dry weight for FRAP and 93.29% for BCB respectively. The in vitro anti-tyrosinase and vitamin C content evaluation of the optimized extract showed a good tyrosinase inhibition of 66.29% with IC50 of 24.06 µg/mL while the vitamin C content was 5.45 mg/g of the extract. The GC-MS analysis revealed the presence of thirty phytoconstituents with l-(+)-ascorbic acid 2,6-dihexadecanoate being the most abundant with a peak area of 14.66%. This study evidently suggests the potential of red pitaya peels to be exploited as a natural skin whitening agent in the cosmeceutical and pharmaceutical formulations.

Larvicidal spirobisnaphthalenes from the endophytic fungus Berkleasmium sp. against Aedes albopictus

BACKGROUND

In our screening programme for new agrochemicals from endophytic fungi, the ethyl acetate extract of an endophytic Berkleasmium sp. isolated from the medicinal plant Dioscorea zingiberensis was found to possess strong larvicidal activity against the Asian tiger mosquito, Aedes albopictus.

RESULTS

Bioassay-guided fractionation of the fungal extract has led to the isolation of seven spirobisnaphthalenes, including palmarumycins C8, C12, C15 and B6 and diepoxins γ, δ and ζ. Among them, palmarumycins C8 and B6 showed strong larvicidal activity against the fourth-instar larvae of A. albopictus, with LC50 values of 8.83 and 11.51 µg mL(-1) respectively. Interestingly, only spirobisnaphthalenes with a chlorine substituent possessed strong larvicidal activity.

CONCLUSION

The results indicated that the spirobisnaphthalenes derived from the endophytic fungus Berkleasmium sp. could be promising leads for the development of new larvicides against A. albopictus.

Enhancement of Palmarumycin C12 and C13 Production by the Endophytic Fungus Berkleasmium sp. Dzf12 in an Aqueous-Organic Solvent System

The endophytic fungus Berkleasmium sp. Dzf12, isolated from Dioscorea zingiberensis, was found to produce palmarumycins C₁₂ and C₁₃ which possess a great variety of biological activities. Seven biocompatible water-immiscible organic solvents including n-dodecane, n-hexadecane, 1-hexadecene, liquid paraffin, dibutyl phthalate, butyl oleate and oleic acid were evaluated to improve palmarumycins C₁₂ and C₁₃ production in suspension culture of Berkleasmium sp. Dzf12. Among the chosen solvents both butyl oleate and liquid paraffin were the most effective to improve palmarumycins C₁₂ and C₁₃ production. The addition of dibutyl phthalate, butyl oleate and oleic acid to the cultures of Berkleasmium sp. Dzf12 significantly enhanced palmarumycin C₁₂ production by adsorbing palmarumycin C₁₂ into the organic phase. When butyl oleate was fed at 5% (v/v) in medium at the beginning of fermentation (day 0), the highest palmarumycin C₁₂ yield (191.6 mg/L) was achieved, about a 34.87-fold increase in comparison with the control (5.3 mg/L). n-Dodecane, 1-hexadecene and liquid paraffin had a great influence on the production of palmarumycin C₁₃. When liquid paraffin was added at 10% (v/v) in medium on day 3 of fermentation, the palmarumycin C₁₃ yield reached a maximum value (134.1 mg/L), which was 4.35-fold that of the control (30.8 mg/L). Application of the aqueous-organic solvent system should be a simple and efficient process strategy for enhancing palmarumycin C₁₂ and C₁₃ production in liquid cultures of the endophytic fungus Berkleasmium sp. Dzf12.

Enhanced production of botrallin and TMC-264 with in situ macroporous resin adsorption in mycelial liquid culture of the endophytic fungus Hyalodendriella sp. Ponipodef12

Hyalodendriella sp. Ponipodef12, an endophytic fungus from the hybrid "Neva" of Populus deltoides × P. nigra, is a high producer of the bioactive dibenzo-α-pyrones botrallin and TMC-264. However, both the botrallin and TMC-264 produced by Hyalodendriella sp. Ponipodef12 were retained as both intracellular and extracellular products. The aim of this study was to evaluate an in situ macroporous resin adsorption for enhancement of botrallin and TMC-264 production in mycelial liquid culture of Hyalodendriella sp. Ponipodef12. Production of botrallin and TMC-264 was most effectively enhanced by macroporous resin DM-301 among the thirteen nonionic macroporous resins tested. The highest botrallin yield (51.47 mg/L, which was 2.29-fold higher than the control at 22.49 mg/L) was obtained by adding resin DM-301 at 4.38% (g/mL) to the culture broth on day 24 and allowing a period of 4 days for adsorption. The highest TMC-264 yield reached 47.74 mg/L, which was 11.76-fold higher than that of the control (4.06 mg/L), and was achieved by adding DM-301 resin at 4.38% (w/v) in the culture broth on day 24 and allowing a period of 6 days for adsorption. The results show that in situ resin adsorption is an effective strategy for enhancing production of botrallin and TMC-264, and also for facilitating their recovery from mycelial liquid culture of Hyalodendriella sp. Ponipodef12.