The environmental pollution that occurs in direct response to the widespread use of man-made/conventional pesticides results from many chemicals that require a long period of time, often decades, to degrade. The synthetic nature of pesticides also harms animals, beneficial insects, microorganisms, and plants, as well as humans. Fortunately, however, there are many natural pesticides, the so-called biopesticides, that are also effective against pests and more importantly, do not interfere with the well-being of ecosystems. Consequently, most biopesticides are safer for use around people and pets than man-made pesticides because, for example, they can be easily washed away from fruits and vegetables. The natural habitat is a rich resource with a wide selection of plants, many of which are also used to treat diseases in humans, animals, and plants. Out of concern for public health, environmental safety, and the stringent regulation of pesticide residues in agricultural commodities, the use of biopesticides is becoming increasingly important, but questions regarding potential pest resistance to these products may arise, just as is the case with conventional pesticides. Therefore, the performance and potential role of biopesticides in the management of plant pests should be prioritized due to their sustainability and importance to human and environmental welfare. In this review, we propose to highlight a scenario in which we discuss in detail the main constraints posed by the use of pesticides compared to biopesticides, starting with issues regarding their definition and continuing on to issues related to their toxicity and their impact on the environment and human health.

The use of biosorbents for the decontamination of industrial effluent (e.g., wastewater treatment) by retaining non-biodegradable pollutants (antibiotics, dyes, and heavy metals) has been investigated in order to develop inexpensive and effective techniques. The exacerbated water pollution crisis is a huge threat to the global economy, especially in association with the rapid development of industry; thus, the sustainable reuse of different treated water resources has become a worldwide necessity. This review investigates the use of different natural (living and non-living) microbial biomass types containing polysaccharides, proteins, and lipids (natural polymers) as biosorbents in free and immobilized forms. Microbial biomass immobilization performed by using polymeric support (i.e., polysaccharides) would ensure the production of efficient biosorbents, with good mechanical resistance and easy separation ability, utilized in different effluents’ depollution. Biomass-based biosorbents, due to their outstanding biosorption abilities and good efficiency for effluent treatment (concentrated or diluted solutions of residuals/contaminants), need to be used in industrial environmental applications, to improve environmental sustainability of the economic activities. This review presents the most recent advances related the main polymers such as polysaccharides and microbial cells used for biosorbents production; a detailed analysis of the biosorption capability of algal, bacterial and fungal biomass; as well as a series of specific applications for retaining metal ions and organic dyes. Even if biosorption offers many advantages, the complexity of operation increased by the presence of multiple pollutants in real wastewater combined with insufficient knowledge on desorption and regeneration capacity of biosorbents (mostly used in laboratory scale) requires more large-scale biosorption experiments in order to adequately choose a type of biomass but also a polymeric support for an efficient treatment process.

Natural plant protection products (known as biopesticides), derived from natural materials (plants, bacterial strains, and certain minerals) that can be used to control pests, are an alternative to plant protection chemicals (known as pesticides) due to certain advantages: less toxic to humans and the environment, no release/leaching of harmful residues, and usually much specific to the target pests. This review focuses on the systematization of information highlighting the main advantages related to the natural plant protection products used, the extractive methods of obtaining them, their physical-chemical analysis methodology, the specific constituents responsible for their pesticide effects, the mechanisms of action, and methods for direct application on vegetable crops or on seeds stored in warehouses, in order to eliminate the adverse effects occurred in the case of plant protection chemicals use. Special attention has been accorded to natural plant protection products from the spontaneous flora of Moldova (Romania’s macroeconomic region NE), which can be considered a resource of valuable secondary metabolites, especially in the form of vegetable essential oils, with biological effects and biopesticide routes of action. All presented information concludes that biopesticides can successfully replace the chemical plant protection products on small farms and especially in silos (seeds and cereals).

The use of a biosorbent based on residual biomass from brewing industry (Saccharomyces pastorianus) immobilized in a natural biopolymer (sodium alginate) was investigated for Methylene Blue removal from aqueous medium. Saccharomyces pastorianus, immobilized by a simple entrapment technique and by microencapsulation in alginate was characterized using SEM, EDAX, pH_PZC and the biosorption behavior toward organic pollutant, such as cationic dye. The biosorption experiments were studied by assessing, in a first stage, the influence of the most important operational physical parameters on the efficiency of the biosorbent: the initial concentration of the dye, the contact time between phases, the temperature, the dye solution pH, the biosorbent granule size, and the amount of biosorbent. The highest sorption capacity was obtained for the biosorbent obtained by microencapsulation, at pH 9, at biosorbent dose of 5.28 g/L and a contact time of about 100 min. The biosorption equilibrium was then studied by modeling the data on the Langmuir, Freundlich and Dubinin- Radushkevich isotherms. The Langmuir model is best suited for experimental data on both particle sizes leading to a maximum biosorption capacity of 188.679 mg/g at room temperature. The values of the adsorption energy, E, obtained with the help of the Dubinin-Radushkevich model-suggest that the type of mechanism (physical or chemical) involved in the biosorption process depends on the particle size of the biosorbent. The results confirm that the residual microbial biomass of Saccharomyces pastorianus immobilized in a polymeric matrix such as sodium alginate, can be considered an efficient biosorbent in retaining cationic organic dyes present in aqueous solutions in moderate concentrations.