Alterations in Mycelial Morphology and Flow Cytometry Assessment of Membrane Integrity of Ganoderma boninense Stressed by Phenolic Compounds

Ethanolic cashew leaf extract: Antifungal activity and its application for shelf-life extension of dried salted tilapia fillets

Ethanolic cashew leaf extract (ECLE) is rich in phenolic compounds with diverse bioactivities and can serve as a safe natural preservative. This study evaluated the antifungal activity and application of ECLE for shelf-life extension of dried salted tilapia fillets. Several extraction methods, antifungal activity, and application of ECLE in dried salted tilapia fillets were investigated. Ultrasonication followed by the Soxhlet extraction resulted in the highest yield (26.78%), total phenolic content (TPC), and total flavonoid content (TFC) (p < 0.05). Conversely, the Soxhlet extraction method rendered lower yield (14.35%), TPC, and TFC (p < 0.05). NaCl at high concentrations decreased both TPC and TFC in all ECLE samples, demonstrating the decomposition of those compounds induced by NaCl. ECLE obtained via the Soxhlet extraction method exhibited lower minimum inhibitory concentration (MIC) and minimum fungicidal concentration values than those prepared using other extraction methods. Thus, the former showed higher efficacy in inhibiting fungal growth and reducing mycelium growth than others (p < 0.05), despite being less effective than potassium sorbate. At 4MIC, ECLE inhibited mycelium growth (56.83%-78.66%) and spore germination (87.5%-100%) after 72 h and 10-16 h of treatment, respectively. ECLE (4MIC) could inhibit the toxin production of fungi. For the challenge test, in which ECLE at 400 and 600 mg/kg was added to dried salted tilapia fillet inoculated with Aspergillus flavus, fungal growth was retarded over 9 days of storage at 25 ± 2°C (room temperature). Thus, ECEL could act as a natural food preservative to prevent fungal contamination. Toxin from fungi could be avoided, and the quality of dried salted fish was maintained. PRACTICAL APPLICATION: Cashew leaf extract rich in polyphenols can inhibit fungal proliferation, reduce mycelium expansion, prevent spore germination, and limit aflatoxin production. The extract can enhance the safety of dried salted fish, especially when contaminated with Aspergillus flavus in the humid atmosphere (80% relative humidity), particularly for small and medium enterprises. Nevertheless, this extract can also be applied in the fish processing industry, in which the synthetic antifungal agent could be replaced by the natural additive.

Ganoderma tuberculosum Liquid Culture With Vineyard Pruning Extracts for Bioactive Composite Production With Antiproliferative Activity

Ganoderma species have been studied for their pharmacological approaches, such as anticancer, antitumor, antiproliferative, and antioxidant activity. Elicitors are used to increase Ganoderma bioactive composite production. This study aims to evaluate the antiproliferative activity of ethanolic extracts from mycelium of Ganoderma tuberculosum (G. tuberculosum) grown in a liquid medium with vineyard pruning waste (VPW) extracts as elicitors. Ethanolic and aqueous VPW extracts contain resveratrol dimer 4, resveratrol tetramer 1, and naringenin, while toluene and chloroform extracts contain tetradecanoic acid, hexadecanoic acid, and octadecanoic acid. Polar and nonpolar extracts could be promising elicitors for increasing bioactive molecules. Catechin gallate showed the highest correlation (r = 0.66) with biomass. Mycelial ethanolic extracts of G. tuberculosum (native strain from the Sonoran Desert) and Ganoderma lucidum (G. lucidum) (control) were analyzed by ESI-IT-MS, and 27 molecules were identified for the two species. They showed antiproliferative activity against the A549 and C-33 A cell lines but not for ARPE-19. G. tuberculosum culture with VPW had quinic acid, ganodermenonol, ganoderic acid I (GA-I), C2 (GA-C2), and 20-hydroxylucidenic acid P, among others. Molecular docking of ganodermenonol, GA-I, and GA-C2 demonstrates significant interaction with tumor necrotic factor (TNF-α). These ethanolic extracts of Ganoderma are promising sources of bioactive triterpenoids. Their antiproliferative activity did not change between species or treatment. Likewise, the G. tuberculosum and G. lucidum extracts only affected cancer cell lines. This property seems promising for pharmacological applications of these fungal extracts.

Pinonic Acid Derivatives Containing Thiourea Motif: Promising Antifungal Lead Compound Targeting Cellular Barrier of Colletotrichum fructicola

In order to explore novel antifungal lead compounds from plant essential oil, thirty-two pinonic acid derivatives containing thiourea groups were designed and synthesized using α-pinene as a raw material. One of these pinonic acid derivatives compound 3a exhibited noteworthy in vitro antifungal activity against Colletotrichum fructicola (EC50 = 9.22 mg/L), which was comparable to that of the positive control kresoxim-methyl (EC50 = 9.69 mg/L). Structure-activity relationship (SAR) studies demonstrated that the introduction of thiourea groups, F atoms, and Cl atoms into the structure of pinonic acid derivatives significantly improved their antifungal activity. The in vivo antifungal test revealed that compound 3a could effectively control pear anthracnose. It also proved that compound 3a showed low acute oral toxicity to honeybees (LD50 > 100 μg/bee) and low or no cytotoxicity to LO2 and HEK293 cell lines. The preliminary mechanism of action studies revealed that compound 3a caused mycelium deformity, increased cell membrane permeability, blocked the normal process of phospholipase C on the cell membrane, and reduced mycelium protein content. The results of molecular docking studies demonstrated the stable binding of compound 3a to phospholipase C and chitin synthetase. This study suggested that compound 3a could be used as a promising lead compound for the development of novel antifungal agents targeting the cellular barrier of C. fructicola.

An In-Depth Study of Phytopathogenic Ganoderma: Pathogenicity, Advanced Detection Techniques, Control Strategies, and Sustainable Management

Phytopathogenic Ganoderma species pose a significant threat to global plant health, resulting in estimated annual economic losses exceeding USD (US Dollars) 68 billion in the agriculture and forestry sectors worldwide. To combat this pervasive menace effectively, a comprehensive understanding of the biology, ecology, and plant infection mechanisms of these pathogens is imperative. This comprehensive review critically examines various aspects of Ganoderma spp., including their intricate life cycle, their disease mechanisms, and the multifaceted environmental factors influencing their spread. Recent studies have quantified the economic impact of Ganoderma infections, revealing staggering yield losses ranging from 20% to 80% across various crops. In particular, oil palm plantations suffer devastating losses, with an estimated annual reduction in yield exceeding 50 million metric tons. Moreover, this review elucidates the dynamic interactions between Ganoderma and host plants, delineating the pathogen's colonization strategies and its elicitation of intricate plant defense responses. This comprehensive analysis underscores the imperative for adopting an integrated approach to Ganoderma disease management. By synergistically harnessing cultural practices, biological control, and chemical treatments and by deploying resistant plant varieties, substantial strides can be made in mitigating Ganoderma infestations. Furthermore, a collaborative effort involving scientists, breeders, and growers is paramount in the development and implementation of sustainable strategies against this pernicious plant pathogen. Through rigorous scientific inquiry and evidence-based practices, we can strive towards safeguarding global plant health and mitigating the dire economic consequences inflicted by Ganoderma infections.

Ganoderma boninense: general characteristics of pathogenicity and methods of control

Ganoderma boninense (G. boninense) is a soil-borne fungus threatening oil palm at the present. It causes basal stem rot disease on oil palm. Within six months, this fungus can cause an oil palm plantation to suffer a significant 43% economic loss. The high persistence and nature of spread of G. boninense in soil make control of the disease challenging. Therefore, controlling the pathogen requires a thorough understanding of the mechanisms that underlie pathogenicity as well as its interactions with host plants. In this paper, we present the general characteristics, the pathogenic mechanisms, and the host's defensive system of G. boninense. We also review upcoming and most promising techniques for disease management that will have the least negative effects on the environment and natural resources.