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The immune response against pathogens, both in plants and animals, relies on a complex recognition system of danger signs. This system is based on the recognition of exogenous molecules termed Microbe- or Pathogen-Associated Molecular Patterns (MAMPs/PAMPs), and endogenous signals called “Damage-Associated Molecular Patterns” (DAMPs). This review will focus on DAMPs, which are molecules with a normal physiological state inside the cell, but at the time of damage or infection are usually released to the extracellular media, indicating cell damage. DAMPS are represented by a wide range of molecules consisting in small peptides, proteins, carbohydrates, cell wall fragments, extracellular ATP (eATP), extracellular DNA (eDNA) and volatile organic compounds (VOCs). Here we review plant DAMPs types and a new approach in eDNA use as biotechnological molecules for plant disease prevention. In particular, self-eDNA has gained importance due to its function of growth inhibition observed over a wide variety of organisms, this function is being studied as a new strategy for biological control to obtain highly pathogen-specific products, without wasting time and research resources. On the other hand, eDNA, as other DAMPs, could act as an immune response elicitor, which could conduce to a new approach for the protection of crops against pests.

In the quest for developing a biological-based nanomaterial for therapeutic applications, here we report a novel benign method of silver nanoparticles synthesized using the endophytic fungi Phomopsis liquidambaris strain SA1 (SAAgNPs). A viable method was developed to generate silver nanoparticles by reacting with silver nitrate and an extracellular filtrate of P.liquidambaris as a reducing and stabilizing agent. After formation of brown color, synthesized SAAgNPs was measured for its Surface Plasmon Resonance (SPR) which produces an intense absorption spectrum at 430 nm. Fourier Transform Infrared Spectroscopy (FTIR) revealed the functional group moieties involved as a capping and reducing agent in SAAgNPs synthesis. Stable, spherical and polydispersed nanoparticles with an average size of 18.7 nm were affirmed by Transmission Electron Microscope (TEM). X-ray Diffraction study showed the diffraction peaks corresponds to (111), (200), (220) and (311) planes resembling cubic crystalline in nature. Energy dispersive analysis (EDAX) identifies the silver as a major compositional element. Moreover, SAAgNPs performed better growth inhibitory activity against the tested pathogens. Further, SAAgNPs arrest the growth of IInd and IVth instar larvae of Aedes aegypti and Culex quinquefasciatus in a dose-dependent method. Finally, SAAgNPs exhibited very low hemolytic activity; suggesting the biocompatibility and feasibility of SAAgNPs as a therapeutic agent. Thus, the study bestowed the isolation of endophytic fungi Phomopsis liquidambaris and its mediated synthesis of silver nanoparticles. Further, SAAgNPs proved its efficacy as an effective antimicrobial and mosquitocidal agent.

The environmental impacts of nanoparticles are explored, particularly exo-polysaccharides, organic molecules, and bio-minerals, which comprise nanocrystals and mesocrystals composed of nanoparticle aggregates. An increasing number of recent studies on Engineered NPs have shown the detrimental effect on the various environmental compartments. As a result, a more comprehensive understanding of nanoparticles’ elemental speciations, distributions, transport mechanisms, and phyto-toxic impacts is crucial. Because of their possible health risks, and their impact on biologically active elements in specific environmental matrices, qualitative and quantitative in-situ measurements of nanoparticle distributions and interactions are necessary. Specifically, nanoparticle applications displaying heterogeneous distribution patterns of metals in different environmental matrices are discussed along with analysis of changes in chemical speciation via synchrotron radiation systems.

Upon screening for novel and potential biocompounds with larvicidal activities, we successfully isolated hamisonine (HMSN) a limonoid compound from endophytic fungi Penicillium oxalicum LA-1 of Limonia acidissima. The extracted compound structure was elucidated by spectral studies such as UV-vis spectroscopy, thin-layer chromatography, FTIR, LC-ESI-MS, 1H NMR, and 13C NMR upon comparing with the spectral data available in the literature. Further, the isolated HMSN was tested against III and IV instar Culex quinquefasciatus larvae. The outcome of this study clearly emphasize that the extracted compound HMSN possesses a stupendous larvicidal activity in a dose-dependent manner with the LC50 and LC90 values of 1.779 and 7.685 ppm against III instar larvae and 3.031 and 28.498 ppm against IV instar larvae of C. quinquefasciatus, respectively. Interestingly, the histological studies evidently showing the damage of peritrophic membrane and epithelial cells of testing mosquito larvae.

Chrysin (5,7-dihydroxy flavone, ChR) is a flavone of plant origin, possessing numerous biomedical properties, such as antimicrobial, anti-inflammatory, anti-diabetic, anxiolytic, hepatoprotective, anti-aging and anticonvulsant activities. In this study, chrysin-producing fungal endophytes (A. alternata KT380662, C. capsici KT373967, and C. taiwanense PI-3 KX580307) were isolated from the leaves of Passiflora incarnata L. and characterised via morphology and internal transcribed spacer (ITS) sequences. Thin layer chromatography and high-performance liquid chromatography profiles of fungal extracts showed Rf values and retention times that closely match those of standard chrysin (ChR). Further, the production of fungal chrysin (FChR) was confirmed through UV-vis spectroscopy, FT-IR, LC-ESI-MS, and 1H1 NMR analysis. Among the isolated strains, A. alternata KT380662 was identified as having a high-level of ChR production, with rates measuring approximately 846 mg L−1. On the other hand, in vitro anticancer and radical scavenging studies proved that FChR has significant cytotoxic activity against human liver carcinoma cells (HepG2). These results clearly imply that the isolated A. alternata KT380662 could serve as an alternative source for the commercial production of ChR, which holds anticancer and radical scavenging activities, and the fungal-derived ChR can be used in chemotherapy or in prodrug development.

The encapsulation of bacteriocins from lactic acid bacteria has involved several methods to protect them from unfavourable environmental conditions and incompatibilities. This review encompasses different methods for the encapsulation of bacteriocins and their applications in both food and pharmaceutical fields. Based on the bibliometric analysis of publications from well-reputed journals including different available patents during the period from 1996 to 2017, 135 articles and 60 patents were collected. Continent-wise contributions to the bacteriocins encapsulation research were carried out by America (52%), Asia (29%) and Europe (19%); with the United States of America, Brazil, Thailand and Italy the countries with major contributions. Till date, different methods proposed for encapsulation have been (i) Film coatings (50%), (ii) Liposomes (23%), (iii) Nanofibers (22%) and (iv) Nanoparticles (4%). Bacteriocins encapsulation methods frequently carried out in food protection (70%); while in the pharmaceutical field, 30% of the research was conducted on multi drug resistant therapy.

In this study, extracellular metabolites of symbiotic bacteria Xenorhabdus stockiae (KT835471) was employed for the synthesis of silver (XsAgNPs) and gold nanoparticles (XsAuNPs). Synthesized NPs were characterized using high throughput instrumentation which confirms the generation of stable, crystalline XsAgNPs and XsAuNPs with the mean size of 14 ± 6 and 14 ± 5, respectively. Further, the NPs exhibits an excellent bactericidal effect against six different pathogens. On the other hand, NPs displayed an outstanding anticancer activity against human lung adenocarcinoma epithelial cells (A549). Therefore, the present study strongly suggests that metal NPs encrusted with functional bio-moieties can be used for different biomedical applications.