The effects of pesticide mixtures on degradation of pendimethalin in soils

Most agronomic situations involve a sequence of herbicide, fungicide, and insecticide application. On the other hand, use of pesticidal combinations has become a standard practice in the production of many agricultural crops. One of the most important processes influencing the behavior of a pesticide in the environment is its degradation in soil. It is known that due to several pesticide applications in one vegetation season, the pesticide may be present in mixtures with other pesticides or xenobiotics in soil. This study examines the role which a mixture of chemicals plays in pesticide degradation. The influence of other pesticides on the rate of pendimethalin (PDM) degradation in soil was measured in controlled conditions. Mixtures of PDM with mancozeb or mancozeb and thiamethoxam significantly influenced the degradation of pendimethalin under controlled conditions. The second type of mixtures, with metribuzin or thiamethoxam, did not affect the behavior of pendimethalin in soil. Also, we determined the influence of water content on the rate of pendimethalin degradation alone in two soils and compared it to the rate in three pesticide mixtures. We compared two equations to evaluate the predictors of the rate of herbicide dissipation in soil: the first-order kinetic and the non-linear empirical models. We used the non-linear empirical model assuming that the degradation rate of a herbicide in soil is proportional to the difference of the observed concentration of herbicide in soil at time and concentration of herbicide in the last day of measurement

Secondary plant metabolities as antimicrobial agents

One of the oldest achievements of the human thought is the use of plants and plant extracts in therapeutics. Drugs of a plant origin are characterized by multieffects. In recent years, much interest was directed at medicinal plants containing a mixture of biologically active substances with antimicrobial properties. In medicine, for many years have been used substances extracted from plants and their secondary metabolites and plant extracts, but now due to the development of organic chemistry, pharmacology and medicine, we can determine which biologically active substances produced by these plants are useful. Antimicrobial activity were described for selected groups of plant secondary metabolites, which potentially would allow their use as antimicrobial substances in medicines. These substances can be complementary to basic medical treatment, because their main advantage is a lower incidence of side effects. This paper presents an overview of research on antimicrobial properties of alkaloids, coumarins, flavonoids, terpenoids and essential oils, phytosterols, and tannins and phenolic compounds. Examples of alkaloids active against strains of S. aureus, E. faecalis and E. coli are quindoline (1) and cryptolepine (2) which are components of an extract of Sida acuta [7]. Saal et al. described the effect of 7-amino-4-methylcoumarin (8) and daphnetin (9) isolated from Gingo biloba. These compounds are characterized by activity against strains of the genus S. aureus, E. coli and Salmonella entertidis [5]. Apigenin (15) and amentoflavone (16) have a strong activity against pathogenic fungi Candida albicans, S. cerevisiae, and T. beigelii. Terpenoids are potent phorbol esters (21-26), dustanine (27), 15-acetoxydustaine (28), cycloartenole (29) [14]. Several phytosterols has antibacterial activity [2, 5, 48]. The examples might be: stigmasterol (36), β-sitosterol (37), epidoxysterol (38) isolated from Morinda citrifolia (Rubiaceae), which were characterized by strong activity against Mycobacterium intracellulare [5]. Many authors reported that the tannins and phenolic compounds were characterized by antimicrobial activity [49-53]. Natural substances that inhibit the growth of microorganisms are becoming an alternative to synthetic compounds, as this literature review confirms it

Selected cooling compounds used in cosmetics

Menthol and new cooling compounds are widely used to improve modern toothpastes, gums, breath fresheners, cosmetic lotions, deodorants, shaving gels, and shaving aid composites. This paper reviews the use of menthol and new classes of cooling agents, that have been discovered since the 1970s, in cosmetic preparations. We have presented here 57 chemical structures. In addition, we briefly touch upon cold receptors and mechanism of action. Finally, we add up, recent findings on the production of cooling ingredients in the world. The underlying process in thermoreception depends on ion transport across cellular membranes. Thermoreceptors belong to a class of transient receptor potential (TRP) channels. Among them are temperature-sensitive thermoreceptors TRPM8 or TRPA 1. Certain types of chemical agonists activate the same thermoTRP channels, as for example menthol or icilin. Only the (–)-menthol enantiomer possesses clean, desirable minty odor and intense cooling properties (Fig. 1). Natural menthol is normally about 99.0% to 99.6% pure, with the remaining impurities being other constituents found in the cornmit oil. Synthetic (–)-menthol is normally about 99.8% pure and has less of the minty top note than the natural menthol. The other natural and synthetic compounds being menthol-related coolants are showed in Figure 3, as for example, menthone 1,2-glycerol ketal (17). From among 3-carboxamide-p-menthane derivatives as commercial cooling agents (Fig. 4), there are for example N-ethyl-pmenthane- 3-carboxamide (25) as WS-3 and [ethyl 3-(p-menthane-3-carboxamido) acetate] as WS-5, which is currently the coldest of all commercial cooling agents (27). Other examples of recently discovered carboxamide coolants belong to a series of analogs of WS-23 (28). Of particular interest are various aryl p-menthane-3- carboxamides, such as N-benzo[1,3]dioxol-5-yl-3-p-menthanecarboxamide (36), which was reported to have 100 times more cooling intensity than menthol (Fig. 6). In 2010, Furrer disclosed a series of new p-menthane carboxamide and WS-23 analogs as cooling agents [56]. Three particularly potential cooling agents 50, 51 and 52 are shown in Figure 9

Essential oils as an active ingredients or preservativies in cosmetics

An important trend in current cosmetic industry is increasing demand for new, biologically active compounds and preservatives of natural origin. These products constitute a major ingredients of natural (organic) cosmetics and usually may also be used in typical cosmetics as functional additives. This work summarizes the perspectives of the use of essential oils as active ingredients and preservatives in cosmetic products and as biopesticides. Brief characteristics of essentials oils, their preparation and biological activity is provided. Literature data suggests that essential oils exhibit broad therapeutic effects including antibacterial, antiseptic, antifungal and antioxidant activity, they can be also used as transdermal enhancers. On the other hand, in essential oil have been found compounds which can be use as a biopesticides. The use of essential oils in cosmetic products is possible, but requires a detailed knowledge regarding their compatibility, active concentration as well as toxicological and skin irritant characteristics. The literature review, presented in this paper, shows the great potential of essential oils as a biologically active preservatives and antioxidants, repellents and transepidermal enhancers

Use of chlorophyll fluorescence for estimation of some adjuvants efficacy in a mixture with atrazine

W pracy przedstawiono szybką metodę fluorescencji chlorofilu do oceny działania wybranych adiuwantów w mieszaninie z atrazyną na rośliny owsa. Atrazyna jako herbicyd triazynowy jest inhibitorem fotosyntetycznego transportu elektronowego w fotosystemie II, co może być rejestrowane za pomocą specjalnego fluorymetrów. Do po-miarów zastosowano fluorymetr impulsowy PAM-200 firmy Walz, mierzono parametr ETR. Wyniki badań wykazały zróżnicowanie reakcji roślin na zastosowane preparaty zależnie od rodzaju zastosowanego adiuwantu. Spośród badanych mieszanin Break-Thrue S-240 i Adbros 85 SL okazały się najbardziej skuteczne, natomiast Adbios 85 SL neutralizował biologiczne działanie atrazyny w mieszaninie z Azoprimem.In the paper is presented a quick chlorophyll fluorescence method for estimation of action of some adjuvants in the mixture with atrazine on oat plants. Atrazine is - a triazine herbicide - is an inhibitor of photosynthetic electron transport in photosystem II, which can be measured by means of the special pulse PAM-200 fluorometer. Results of the ETR measurements show differences between the phytotoxicity of the applied adjuvants. Of the studied mixtures Break-Thrue S-240 and Adbros 85 SL were the most effective, whereas Adbios 85 SL neutralised the biological action of atrazine in the connection with Azoprim

Chemical composition and biological activity of medical lavender

Lavender Lavandula angustifolia Miller (formerly used synonym of L. officinalis Chaix or L. vera), commonly known as medical lavender is a species of greatest industrial importance. Lavender cultivated to be the most frequently due of the essential oil and the unique biological activity [1–4]. It is clear from the literature on the subject that lavender is characterized by its antimicrobial, antifungal, antioxidant, immunostimulating, and spasmolytic activity [5–18]. It is also claimed that it can be effective in preventing many illnesses. It is proved that lavender essential oil can be an effective drug in the treatment of many neurological disorders [13–18]. The research conducted on animals and humans exhibit activity this plant such as anxiolytic, sedative, sleep-inducing, analgesic, antitumor, anticonvulsant, and mood improving [13–26]. This paper presents an overview of the literature from recent years on the lavender [1–93]. The general characteristics of the plant and the main classes of biologically active substances are discussed. Drew attention to the need for standardization of plant and variety, identification of plant material for use in the following industries: pharmaceutical, chemical, cosmetic and food. It was found that there are few studies comparing the activity of different varieties of lavender. There is also little information about the chemical composition of different parts of the plant. There are current studies conducted towards natural synergies. This plant collects various types of biologically active substances that have therapeutic potential, but the lack of relevant information concerning dosage formulations lavender. Medical lavender (L. angustifolia Miller) has a great potential for future applications

Comparison of select kinetic models of herbicides degradation in soil

The aim of the paper was to used of three types of mathematical function: the single first-order degradation kinetics (SFO), Gustafson and Holden model (FOMC) and the simple linear bi-phase model, for quantification of the fate of pesticides in soil. For instance data from laboratory study of dissipation of atrazine in soil was used. Numerical methods using for estimate of structural coefficients of degradation models of this herbicide. For every models assessed the values of 50, 90 and 100% dissipation time of substance active. Mathematical equations and figures of first derivative of functions were presented as the analysis of atrazine degradation process. Accomplishment of estimate ade quately of using models. To the last degree of the kinetics criterions of degradation of substance active and the statistics criterions make good the Gustafson and Holden model. In this work find that analysis of degradation rate is valuable of study integration of kinetics degradation herbicides in soil