PHYTOCHMICAL ANALYSIS AND ANTIFUNGAL POTENTIAL OF SORGHUM HELEPENSE L. FOR THE MANAGEMENT OF OCHRATOXIGENIC FUNGI

Ochratoxigenic fungal species are a major cause of various infections in plants and posed a serious threat to their consumers,including humans and animals. In the current study the objective was to examine the in vitro efficacy of different concentrations of leaves methanolic extract of S. helepense L. (Pers.) against target pathogenic ochratoxin producing fungal species (Trichoderma viride Pers., Trichoderma harzianum Rifai. and Cladosporium cladosporioides (Fresen.) G.A. de Vries).For this purpose, different concentrations viz. 2%, 4%, 6%, 8% and 10% of leaf methanolic extract were prepared and tested for antifungal potential in a completely randomized design (CRD). Results revealed that all the applied concentrations of S. helepense inhibited the growth of all the tested fungal strain. Maximum growth inhibition was observed in 2% of concentration of methanolic extract of S. helepense in case of C. cladosporoides i.e. 84%. On the other hand minimum reduction was observed in 4% of concentration of methanolic extract of S. helepense against T. viride as compared to control. The phytochemical analysis was also conducted to evaluate that which chemical entities were present that account for antifungal potency of methanolic extract of S. helepense. Results of phytochemical analysis revealed the occurrence of saponins, alkaloids, coumarins, flavonoids and tannins while the plant is devoid of terpenoids, phlobatanins and glycosides respectively. Hence it can be concluded that the methanolic leaf extract of the tested plant proved to be beneficial for inhibiting the growth of test ochratoxigenic fungi.

ANTIFUNGAL ACTIVITY OF CHITOSAN AGAINST Rhizopus stolonifer

These days instead of chemical pesticides, various natural alternatives have been used for the management of post-harvest diseases. This research was carried out to evaluate the antifungal potential of different chitosan concentrations viz., 5, 10, and 15 mg/µl against Rhizopus stolonifer by the agar dilution and well diffusion methods. The evaluation was carried out after seven days of incubation by measuring the inhibition of R. stolonifer mycelial growth. Results of the study revealed that the chitosan had a significant inhibitory effect on mycelial growth and maximum mycelial growth inhibition was reported at the 10 and 15 mg/µl concentrations and these two treatments are not significantly different. Based on these results, the best concentration (15 mg/µl) was further evaluated by the well diffusion technique. The average inhibition zones formed by the higher concentration was 25mm. Results of the study suggested that chitosan can be used for the management of post-harvesting diseases of tomatoes.

GC-MS Profiling and Antifungal Activity of Secondary Metabolite from Endophytic Fungus of Giloy

The endophytic microbiota is considered to be one of the consistent and noble souce of potential and unique natural amalgams. These natural amalgams carry diverse pharmaceutical significance which the reason for their importance among research fields. The diversity of plants carries much more diversity of the endophytes as their mutual parts where both are benefited from each other. The current work deals with the isolation of the endophytic fungus from Tinospora cordifolia, for which the leaves were used after the surface sterilization, followed by the production of secondary metabolite by the endophytic isolates through submerged fermentation technique. The produced metabolite was extracted by liquid-liquid extraction technique, which was further used for evaluating its antifungal potential against Candida albicans and the obtained results show their considerable potential. The GC-MS profiling of secondary metabolite was conducted to determine the presence of some bioactive compounds in them, and as a result, some potential compounds detected are Levoglucosenone, Silanediol, Nonane, D-Allose, 5-Hydroxymethylfurfural. Since these compounds are biologically important in various aspects which gives the diversified application to the secondary metabolites. The study concludes the potential of secondary metabolites from endophytic fungus of Tinospora cordifolia and further investigation can be approached on determining the same from other plants, and also evaluating another bioactive potential of secondary metabolites.

The effect of lichen secondary metabolites on Aspergillus fungi

A systematic review of literature data on the antifungal potential of extracted lichen compounds and individual secondary metabolites against mold species of the genus Aspergillus is provided. Crude extracts from 49 epiphytic, 16 epigeic and 22 epilithic species of lichens and 44 secondary metabolites against 10 species, Aspergillus candidus, A. flavus, A. fumigatus, A. nidulans, A. niger, A. ochraceus, A. parasiticus, A. restrictus, A. stellatus and A. ustus, were analysed. Several measuring techniques were employed for such analyses. Lichen substances were extracted with alcoholic and other organic solvents mainly using the Soxhlet apparatus. Among the three most-studied mold species, the results showed that the crude extracts from the thalli of the lichens Cladonia foliacea, Hypotrachyna cirrhata, Leucodermia leucomelos, Platismatia glauca and Pseudevernia furfuracea against Aspergillus flavus, from C. foliacea, Nephroma arcticum and Parmelia sulcata against A. fumigatus and from Evernia prunastri, Hypogymnia physodes, Umbilicaria cylindrica and Variospora dolomiticola against A. niger have the greatest antifungal potential. The lichen secondary metabolites showed a higher inhibitory potential, e.g. protolichesterinic acid against A. flavus, lecanoric acid against A. fumigatus and orsellinic acid against A. niger; the other seven species of Aspergillus have been poorly studied and require further investigation. A comparison of the inhibitory potential of the tested mixtures of lichen substances and their secondary metabolites shows that they can compete with commonly used antifungal substances, such as ketoconazole and clotrimazole against A. flavus, A. nidulans, A. niger and A. parasiticus and fluconazole in the case of A. fumigatus.

Envisaging Antifungal Potential of Histatin 5: A Physiological Salivary Peptide

Fungi are reported to cause a range of superficial to invasive human infections. These often result in high morbidity and at times mortality. Conventional antifungal agents though effective invariably exhibit drug interactions, treatment-related toxicity, and fail to elicit significant effect, thus indicating a need to look for suitable alternatives. Fungi thrive in humid, nutrient-enriched areas. Such an environment is well-supported by the oral cavity. Despite this, there is a relatively low incidence of severe oral and periodontal fungal infections, attributed to the presence of antimicrobial peptides hosted by saliva, viz. histatin 5 (Hstn 5). It displays fungicidal activity against a variety of fungi including Candida albicans, Candida glabrata, Candida krusei, Cryptococcus neoformans, and unicellular yeast-like Saccharomyces cerevisiae. Candida albicans alone accounts for about 70% of all global fungal infections including periodontal disease. This review intends to discuss the scope of Hstn 5 as a novel recourse for the control of fungal infections.

Antimicrobial activity of the edible mushroom Pleurotus eryngii (DC.) Quél grown in liquid medium

Edible mushrooms have a number of medicinal properties and this study aimed to investigate the antimicrobial activity of Pleurotus eryngii DPUA1816 in metabolic broths after being grown in submerged cultivation. Mycelial fragments of pure P. eryngii culture was inoculated in sweet potato culture medium and incubated at 150 rpm for 15 days at 25°C. Pleurotus eryngii was also cultivated for 18 days under the same conditions, the mycelial biomass was separated by filtration for quantification. The supernatant was used in the diffusion test in agar and performed against Escherichia coli CCCD-E005, Staphylococcus aureus CCCD-S009, Pseudomonas aeruginosa CCCD-P004, Candida albicans CCCD-CC001, Candida parapsilosis CCCD-CC004 and Candida tropicalis CCCD-CC002. The samples showed no inhibitory activity against bacteria, however they showed some activity against C. albicans (12.17 mm), C. parapsilosis (27.67 mm) and C. tropicalis (13.67 mm). After being cultivated for 18 days, P. eryngii was able to inhibit all yeasts after 12 days of culture, with an inhibition halo of 29.33 mm at 16 days against C. parapsilosis. This study demonstrates the antifungal potential filtered liquids from P. eryngii cultivated in purple-skinned sweet potato culture medium, which suggests the possibility of the use of this species by the pharmaceutical industry as a natural source of biological action.

Profiling of Antifungal Activities and In Silico Studies of Natural Polyphenols from Some Plants

A worldwide increase in the incidence of fungal infections, emergence of new fungal strains, and antifungal resistance to commercially available antibiotics indicate the need to investigate new treatment options for fungal diseases. Therefore, the interest in exploring the antifungal activity of medicinal plants has now been increased to discover phyto-therapeutics in replacement to conventional antifungal drugs. The study was conducted to explore and identify the mechanism of action of antifungal agents of edible plants, including Cinnamomum zeylanicum, Cinnamomum tamala, Amomum subulatum, Trigonella foenumgraecum, Mentha piperita, Coriandrum sativum, Lactuca sativa, and Brassica oleraceae var. italica. The antifungal potential was assessed via the disc diffusion method and, subsequently, the extracts were assessed for phytochemicals and total antioxidant activity. Potent polyphenols were detected using high-performance liquid chromatography (HPLC) and antifungal mechanism of action was evaluated in silico. Cinnamomum zeylanicum exhibited antifungal activity against all the tested strains while all plant extracts showed antifungal activity against Fusarium solani. Rutin, kaempferol, and quercetin were identified as common polyphenols. In silico studies showed that rutin displayed the greatest affinity with binding pocket of fungal 14-alpha demethylase and nucleoside diphosphokinase with the binding affinity (Kd, −9.4 and −8.9, respectively), as compared to terbinafine. Results indicated that Cinnamomum zeylanicum and Cinnamomum tamala exert their antifungal effect possibly due to kaempferol and rutin, respectively, or possibly by inhibition of nucleoside diphosphokinase (NDK) and 14-alpha demethylase (CYP51), while Amomum subulatum and Trigonella foenum graecum might exhibit antifungal potential due to quercetin. Overall, the study demonstrates that plant-derived products have a high potential to control fungal infections.

Synthesis, Characterization, and Antifungal Activity of Silver Nanoparticles Embedded in Pullulan Matrices

Steady developments made in nanotechnology-based products have facilitated new perspectives for combating drug-resistant fungi. Silver nanoparticles represent one of the most attractive nanomaterials in biomedicine due to their exclusive optical, electromagnetic, and catalytic properties and antifungal potency compared with other metal nanoparticles. Most studies show that the physicochemical parameters affecting the antifungal potential of AgNPs include the shape, size, surface charge, and concentration and colloidal state. For the present study, pullulan (P) and its oxidized counterpart (PO) have been selected as matrices for the silver nanoparticles’ generation and stabilization (AgNPs). The TEMPO (2,2,6,6-tetramethylpiperidin-1-yl radical)–sodium hypochlorite–sodium bromide system was used for the C6 selective oxidation of pullulan in order to introduce negatively charged carboxylic groups in its structure. The structure and morphology of the synthesized AgNPs were analyzed using FTIR and EDX. The main objective of this study was to elucidate the antifungal activity of AgNPs on the clinical yeasts isolates and compare the performance of AgNPs with the conventional antifungals. In this study, different concentrations of AgNPs were tested to examine antifungal activity on various clinical isolates.