Comparative evaluation of propolis nanostructured lipid carriers and its crude extract for antioxidants, antimicrobial activity, and skin regeneration potential

Background

Propolis extracted from beehives has been conferred with natural antimicrobial and antioxidant properties. Hence, it has been recommended as a wound healing therapy. This study investigated the additive value of nanotechnology to the herbal extract, (propolis rebuts), after which we examined its efficacy in wound healing.

Methods

Propolis nanostructured lipid carriers (NLCs) were first prepared using the emulsion-evaporation-solidification method at three concentrations. Then, we compared their flavonoid and phenolic contents and phenolic contents. Their antioxidant, antibacterial, and antifungal effects were also investigated after which, the skin regenerative capacity of propolis-NLCs was assessed using full-thickness skin wounds in rabbits.

Results

This study showed that propolis-NLCs had increased the phenolic and flavonoid contents compared to the raw propolis extract (EXTR) (9-fold and 2-fold, respectively). This increase was reflected in their antioxidant activities, which dramatically increased by 25-fold higher than the propolis-EXTR. Also, propolis-NLCs exhibited a 2-fold higher potent inhibitory effect than propolis-EXTR on Gram-positive bacteria (Bacillus subtilis and Staphylococcus aureus), Gram-negative bacterium (Salmonella spp.), and fungus (Candida albicans) microbes (p < 0.0001). Investigations also revealed that treatment of full-thickness skin injuries with propolis-NLCs resulted in significantly higher wound closure compared to propolis-EXTR and the control after two weeks (p < 0.0001).

Conclusion

With a prominent broad-spectrum antibacterial effect propolis-NLCs exhibited higher skin regenerative potency than propolis-EXTR. We also highlighted the additive impact of nanotechnology on herbal extract, which accounted for the increased flavonoid content and hence a better antioxidant and antimicrobial effect and propose it as a potential therapy for wound healing.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12906-022-03737-4.

Development and characterization of niosomal gel of fusidic acid: in-vitro and ex-vivo approaches

Niosomes are multilamellar vesicles that efficiently deliver active substance into skin systemic circulation or skin layers. They are used in topical drug delivery system to enhance the skin permeation of active substance. So, the prime objective of this study was to develop a niosomal gel of fusidic acid to increase its skin permeation. Different formulations of niosomes of fusidic acid were designed by varying the cholesterol to surfactant ratio. Formulations containing fusidic acid, cholesterol, dihexadecyl pyridinium chloride, Span 60, or Tween 60 were prepared by thin film hydration method in rotary evaporator. The thin film formed in rotary flask was hydrated by phosphate buffer saline of pH 7.2. The niosomes formed were characterized through entrapment efficiency, size, polydispersity index (PDI), and zeta potential. The S3 formulation containing span 60 showed the highest entrapment efficiency (EE) of niosomes, so it was incorporated into Carbopol gel. Determination of pH, spreadability, rheological, and ex vivo permeation studies was conducted of niosomal gel. The results of ex vivo permeation studies showed high permeation of fusidic acid when gel was applied to an albino rat skin. According to the results and previous studies of niosomes, it can be concluded that niosomes enhanced the permeation of fusidic acid through the skin.

Design, formulation and evaluation of Chasmanthera dependens Hochst and Chenopodium ambrosioides Linn based gel for its analgesic and anti-inflammatory activities

Background

The incidence of pain and inflammation in West Africa and in fact globally, continues to increase at an alarming rate. This research was conducted to investigate the analgesic and anti-inflammatory activities of leaf extracts of Chasmanthera dependens and Chenopodium ambrosioides; formulate and evaluate polyherbal gels from their combination in a bid to providing topical therapeutic solutions to pain and inflammation.

Methods

Pre-formulation studies (phytochemical analysis, in vitro analgesic and anti-inflammatory activities) were conducted on the methanol leaf extracts of Chasmanthera dependens and Chenopodium ambrosioides. Individual and polyherbal gels were prepared using polymer carbopol 940 (1%) at combination ratios of 0:100, 25:75, 50:50, 75:25 and 100:0 Chasmanthera:Chenopodium. These herbal gels were evaluated for physical parameters, pH, viscosity, extrudability and spreadability. Analgesic and anti-inflammatory activities of herbal gels were evaluated by their inhibitory activities (percentage inhibition) against COX-2, TNF-α, IL-10, PGE-2 and compared with commercial diclofenac gel.

Results

The phytochemicals of the two extracts detected gave varied contents of major classes of secondary metabolites. The pre formulation inhibitory studies of the two extracts exhibited dose dependent inhibitory activities against COX-2, TNF-α, IL-10, PGE-2. The physical appearance, homogeneity, and consistency of the herbal formulations were good. The herbal gels were spreadable with good extrudability. The pH of the herbal gels ranged from 4.5 ± 0.4 to 5.2 ± 0.4. The viscosity of the herbal gels ranged between 4.3 ± 0.2 and 4.7 ± 0.4 Pas. The herbal gels exhibited significant differences in inhibitory activities against COX-2, TNF-α, IL-10, PGE-2 when compared with control commercial diclofenac gel.

Conclusion

The outcomes, including the inhibition of mediators COX-2, TNF-α, IL-10, PGE-2, confirm the use of the plant extracts under study, the individual and polyherbal gels formulated for the potential topical therapeutic treatment of pain and inflammation.

Efficacy of Phytopharmaceuticals From the Amazonian Plant Libidibia ferrea for Wound Healing in Dogs

We comparatively evaluate two distinct formulations containing 5% of Jucá (Libidibia ferrea) for wound healing in dogs. An excision model study was performed in 11 dogs with three dermal wounds in each animal, which were treated with: (1) topical phytopharmaceutical based on Carbopol (PyC) containing 5% Jucá ethanolic extract; (2) topical phytopharmaceutical based on Astrocaryum murumuru butter (PyM) containing 5% Jucá ethanolic extract; and (3) commercial ointment (control). Wound treatment was carried out on alternated days starting at day (D) one until D21. Macroscopic (all time-points) and histological (D0 and D21) analyses were performed. The antimicrobial activity of Jucá was evaluated through Minimal Inhibitory Concentration (MIC). Phytochemical analysis of Jucá revealed 3.1% phenolic compound content expressed in rutin and the presence of hydrolyzable tannins and flavonoids. The mean wound retraction was 33.7 ± 5.5, 34.0 ± 4.7, and 28.4 ± 4.9 % for PyC, PyM, and control groups, respectively, with higher wound retraction for both herbal-treated groups compared to the control (P < 0.05). Alcoholic extract of Jucá had antimicrobial activity against the microorganisms Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, and Candida krusei at different degrees, with MIC ranging from 250 to 16.625 μg/ml. Microscopic evaluation showed that the phytotherapic formulations contributed to better dermal wound healing through wound fibroplasia. The alcoholic extract of Jucá pods has great potential for wound healing in dogs and can be used in the development of commercially viable phytotherapic formulations.

Lipid-polymer hybrid nanoparticles: Development & statistical optimization of norfloxacin for topical drug delivery system

Poly lactic acid is a biodegradable, biocompatible, and non-toxic polymer, widely used in many pharmaceutical preparations such as controlled release formulations, parenteral preparations, surgical treatment applications, and tissue engineering. In this study, we prepared lipid-polymer hybrid nanoparticles for topical and site targeting delivery of Norfloxacin by emulsification solvent evaporation method (ESE). The design of experiment (DOE) was done by using software to optimize the result, and then a surface plot was generated to compare with the practical results. The surface morphology, particle size, zeta potential and composition of the lipid-polymer hybrid nanoparticles were characterized by SEM, TEM, AFM, and FTIR. The thermal behavior of the lipid-polymer hybrid nanoparticles was characterized by DSC and TGA. The prepared lipid-polymer hybrid nanoparticles of Norfloxacin exhibited an average particle size from 178.6 ± 3.7 nm to 220.8 ± 2.3 nm, and showed very narrow distribution with polydispersity index ranging from 0.206 ± 0.36 to 0.383 ± 0.66. The surface charge on the lipid-polymer hybrid nanoparticles were confirmed by zeta potential, showed the value from +23.4 ± 1.5 mV to +41.5 ± 3.4 mV. An Antimicrobial study was done against Staphylococcus aureus and Pseudomonas aeruginosa, and the lipid-polymer hybrid nanoparticles showed potential activity against these two. Lipid-polymer hybrid nanoparticles of Norfloxacin showed the %cumulative drug release of 89.72% in 24 h. A stability study of the optimized formulation showed the suitable condition for the storage of lipid-polymer hybrid nanoparticles was at 4 ± 2 °C/60 ± 5% RH. These results illustrated high potential of lipid-polymer hybrid nanoparticles Norfloxacin for usage as a topical antibiotic drug carriers.

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Efficient topical drug delivery systems of norfloxacin have been synthesized.

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Norfloxacin loaded to the core of lipid- polymer hybrid nanoparticles were prepared.

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The formulations were optimized by factorial design and characterization techniques.

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A unique formulation of norfloxacin that offer prolonged and control delivery.

Development and Evaluation of Naproxen Sodium Gel Using Piper cubeba for Enhanced Transdermal Drug Delivery and Therapeutic Facilitation

BACKGROUND

The absorption of drug through skin avoids many side effects of oral route like gastric irritation, nausea, systemic toxicity etc and thus improves patient compliance. Naproxen sodium (NPRS) is one of the potent NSAID agents.

OBJECTIVE

The present study was aimed to develop and evaluate the gel formulation containing NPRS for transdermal drug delivery reducing the side effects and improving patient compliance. The patents on topical delivery of NSAIDS (US 9012402 B1, US 9072659 B2, US 20150258196 A1) and patents indicating use of herbal penetration enhancers (US 20100273746A1, WO 2005009510 A2, US 6004969 A) helped in selecting the drug, excipients.

METHOD

Current protocol employs various extracts of Piper cubeba fruit to evaluate its role in absorption of NPRS. Various batches containing 1% NPRS and varying concentrations of synthetic permeation enhancers or the extracts were formulated in carbopol gel. Gel was evaluated for parameters like organoleptic parameters, pH, viscosity and spreadability. An ex-vivo percutaneous absorption of NPRS from gel was investigated and compared with best performing synthetic enhancer, transcutol P (TP).

RESULT

The batch containing 2% n-hexane extract (NHE) of Piper cubeba showed higher permeation than TP and Chloroform (CE), Methanolic (ME) and aqueous (AE) extracts as well. It showed improved % cumulative release (85.09%) and flux (278.61μg/cm2.h), as compared to TP and other extracts. Histopathology indicated the formulation safer as compared to that with synthetic enhancer.

CONCLUSION

It suggests P. cubeba as effective and safer tool for transdermal delivery and acts as therapeutic facilitator for naproxen. GC-MS analysis indicates lignans &amp; terpenes in NHE to which this permeation enhancement activity may be attributed.

Proxy model materials to simulate the elastic properties of digested municipal sludge

The elastic rheological properties of sludge are complex and evolve with time as a result of ageing and microbial activity. Due to the peculiar nature of sludge, this makes the measurement of physical parameters difficul. The challenge is to identify a reference material that can be used as a proxy for industrial process design or optimization. In this study, respectively the mixtures of 0.5%, 0.7% and 1% glass beads suspension in water have been added to 0.5%, 0.7% and 1% carbopol dissolved in water and neutralized with NaOH to prepare gel, at different ratios. Elastic and loss moduli have been determined for different glass bead suspension ratios in the range of 0%-80%. The results showed that there is a critical glass bead suspension/carbopol ratio at which the elastic properties of the mixture changes dramatically. The elastic properties of these model mixtures of different glass bead/carbopol ratio suspensions are compared with the elastic property of municipal sludge sampled from a Melbourne Waste Water Treatment Plant, and similarity established.