Antifungal activity of P3HB microparticles containing tebuconazole

Abstract

In this study, tebuconazole (TEB)-loaded poly-3-hydroxybutyrate (P3HB)-based microparticles were developed and comprehensively characterized. TEB-loaded microparticles (10, 25, and 50%) were prepared using double emulsification technique. Encapsulation efficiency of TEB varied from 59 to 86%. As the loading amount was increased, the average diameter of microparticles increased too, from 41.3 to 71.7 µm, while zeta potential was not influenced by TEB loading, varying between -32.6 and -35.7 mV. TEB was released gradually from 10, 25, and 50% loaded particles, and over 60 days, 25, 43, and 38%, respectively, of the initially loaded amount was released. The data obtained from in vitro TEB release were fitted to different mathematical models. It was shown that the release profiles of TEB could be best explained by Zero-order, Higuchi models and Hixson-Crowell. The antifungal activity of the P3HB/TEB microparticles against phytopathogenic fungi F. moniliforme and F. solani was comparable to that of the free fungicide. Thus, hydrophobic agrochemicals (TEB) can be effectively encapsulated into P3HB microparticles to construct slow-release formulations.

A study of the properties and efficacy of microparticles based on P(3HB) and P(3HB/3HV) loaded with herbicides

“…50,51 The effect of the concentration of the active ingredient was demonstrated in a study by Shershneva et al: the average diameter of P(3HB)/tebuconazole microparticles increased from 41.3 to 71.7 μm as tebuconazole concentration was increased from 10% to 50%. 43 Other authors also reported size heterogeneity of nanoparticles (261.9 ± 35.1 nm) prepared from the P (3HB/3HV) copolymer and loaded with paclitaxel 50 and PLGA composite particles, whose size varied from 220 to 500 nm. 51 The microparticles based on the lowcrystallinity P(3HB/4HB) copolymers and loaded with the trifluralin herbicide were smaller, and their size was less variable (2.5 to 4.0 μm).…”

“…The average diameter of P(3HB) particles loaded with the tebuconazole fungicide ranged between 41 ± 11.2 and 71.0 ± 10.9 μm. 43 The sizes of the P(3HB) and P(3HB/3HV) microparticles loaded with ametryn were 10.6 ± 0.43 and 20.5 ± 0.93 μm, respectively. 39 Another study showed the effect of the 3HB to 3HV ratio in the copolymer, which varied between 24.14 ± 1.6 and 33.5 ± 3.22 μm, on the particle size.…”

“…Kinetics of herbicide release from the polymeric microparticles was studied in vitro in laboratory water systems as described elsewhere. 43 Samples of P(3HB)/herbicide or P(3HB/3HV)/herbicide microparticles (30 mg each sample) were sterilized and placed into sterile 500-ml flasks filled with sterile distilled water (100 ml). The experiment was conducted in triplicate.…”

“…21,34,37,38 Despite the increasing interest of researchers in PHAs, there are few studies reporting encapsulation of pesticides in polymer micro-and nanoparticles. [39][40][41][42][43][44] In contrast to the already published research, the purpose of the present study was to produce controlleddelivery systems for herbicides (metribuzin, tribenuronmethyl, and fenoxaprop-P-ethyl) that differ in their water solubility and activity, based on two biodegradable polymers: P(3HB) and P(3HB/3HV). The present study compared the effects of the chemistry of the polymers and herbicides on the properties of microparticles, their potential for sustained action, and herbicidal activity.…”

“…To reduce the cost and increase the availability of pesticide formulations based on PHAs, the first studies were performed on embedding pesticides into polymer blends with readily available natural materials (clay, peat, and wood flour) 21,34,37,38 . Despite the increasing interest of researchers in PHAs, there are few studies reporting encapsulation of pesticides in polymer micro‐ and nano‐particles 39–44 …”