Response Surface Methodology (RSM)-Based Optimization of Ultrasound-Assisted Extraction of Sennoside A, Sennoside B, Aloe-Emodin, Emodin, and Chrysophanol from Senna alexandrina (Aerial Parts): HPLC-UV and Antioxidant Analysis

In this study, ultrasound-assisted extraction conditions were optimized to maximize the yields of sennoside A, sennoside B, aloe-emodin, emodin, and chrysophanol from S. alexandrina (aerial parts). The three UAE factors, extraction temperature (S1), extraction time (S2), and liquid to solid ratio (S3), were optimized using response surface methodology (RSM). A Box–Behnken design was used for experimental design and phytoconstituent analysis was performed using high-performance liquid chromatography-UV. The optimal extraction conditions were found to be a 64.2 °C extraction temperature, 52.1 min extraction time, and 25.2 mL/g liquid to solid ratio. The experimental values of sennoside A, sennoside B, aloe-emodin, emodin, and chrysophanol (2.237, 12.792, 2.457, 0.261, and 1.529%, respectively) agreed with those predicted (2.152, 12.031, 2.331, 0.214, and 1.411%, respectively) by RSM models, thus demonstrating the appropriateness of the model used and the accomplishment of RSM in optimizing the extraction conditions. Excellent antioxidant properties were exhibited by S. alexandrina methanol extract obtained using the optimized extraction conditions with a DPPH assay (IC50 = 59.7 ± 1.93, µg/mL) and ABTS method (47.2 ± 1.40, µg/mL) compared to standard ascorbic acid.

Aloe Vera in Dentistry: A Review

Aloe Vera is a tender and succulent type of plant belonging to the Liliaceae family and genus Aloe. It has been used as a medicinal plant for its healing and soothing properties for more than 2000 years. Properties of the Aloe Vera are not only specie dependent but also on how it is handled after being collected. Due to the adverse effects associated with conventional drugs, researchers are again interested in pursuing plant-based therapies for diseases. Aloe Vera possesses number of beneficial ingredients whilst some studies have also reported its potentially harmful effects. Presence of Aloe Vera in the scaffold material increases viability of the regenerating cells. It is crucial to understand how Aloe Vera interacts with the human body and its physiology when used for dental diseases and discomforts. Components like anthraquinones, aloe-emodin, and aloin present in the Aloe Vera leaves are responsible for their strong anti-bacterial and anti-viral properties. Therefore, this article reviews the current literature related to Aloe Vera use as a replacement or adjunctive therapy in dental diseases.

Antifungal Effect of Antimicrobial Photodynamic Therapy Mediated by Haematoporphyrin Monomethyl Ether and Aloe Emodin on Malassezia furfur

Infectious dermatological diseases caused by Malassezia furfur are often chronic, recurrent, and recalcitrant. Current therapeutic options are usually tedious, repetitive, and associated with adverse effects. Alternatives that broaden the treatment options and reduce side effects for patients are needed. Antimicrobial photodynamic therapy (aPDT) is an emerging approach that is quite suitable for superficial infections. The aim of this study is to investigate the antimicrobial efficacy and effect of aPDT mediated by haematoporphyrin monomethyl ether (HMME) and aloe emodin (AE) on clinical isolates of M. furfur in vitro. The photodynamic antimicrobial efficacy of HMME and AE against M. furfur was assessed by colony forming unit (CFU) assay. The uptake of HMME and AE by M. furfur cells was investigated by fluorescence microscopy. Reactive oxygen species (ROS) probe and flow cytometry were employed to evaluate the intracellular ROS level. The effect of HMME and AE-mediated aPDT on secreted protease and lipase activity of M. furfur was also investigated. The results showed that HMME and AE in the presence of light effectively inactivated M. furfur cells in a photosensitizer (PS) concentration and light energy dose-dependent manner. AE exhibited higher antimicrobial efficacy against M. furfur than HMME under the same irradiation condition. HMME and AE-mediated aPDT disturbed the fungal cell envelop, significantly increased the intracellular ROS level, and effectively inhibited the activity of secreted protease and lipase of M. furfur cells. The results suggest that HMME and AE have potential to serve as PSs in the photodynamic treatment of dermatological diseases caused by M. furfur, but further ex vivo or in vivo experiments are needed to verify that they can meet the requirements for clinical practice.

Aloe-Emodin-Mediated Photodynamic Therapy Induces Apoptosis in Basal Cell Carcinoma Cells via Activation of ERK/JNK Signaling Pathway

Basal cell carcinoma (BCC) is the most prevalent epidermal cancerous neoplasm. Previous studies have reported the noninvasive, cost-effective, and localized photodynamic therapy (PDT) approach to BCC treatment. This study investigated the photodynamic effects of aloe-emodin (AE), a natural anthraquinone photosensitizer (PS), on proliferation and apoptosis of BCC TE 354.T cell line. To evaluate the effects of AE-mediated PDT, we used various concentrations of AE (0, 2.5, 5, and 10 μM) and white light energy (0, 12, 24, and 36 J/cm2). CCK-8 assay was used to analyse cell viability following AE-mediated PDT. The cell death rate and reactive oxygen species (ROS) were assessed by flow cytometry. Western blotting was used to determine the effects of AE-mediated PDT on the apoptotic proteins, Akt, and MAPK pathways. AE-mediated PDT inhibited tumorigenic cell proliferation, consequently enhancing apoptosis in AE and PDT concentration and dose-dependent manner, respectively. Significantly increased TE 354.T cell apoptosis and intracellular ROS production were both observed after AE-mediated PDT. Following the AE-mediated PDT, cytochrome and antitumor p53 were elevated; however expression of Bcl-2 was significantly decreased. Significant caspase 3 elevation post-AE-mediated PDT suggested intrinsically driven apoptosis. Additionally, AE-mediated PDT significantly suppressed NF-κB, Akt, and ERK pathways while JNK expression was significantly increased. AE-mediated PDT induced TE 354.T cell apoptosis through the intracellular generation of ROS. Akt, ERK, and JNK all play various roles in ensuring successful TE 354.T tumor cell apoptosis.