Valorization of Aloe barbadensis Miller. (Aloe vera) Processing Waste

Aloe vera plant is known worldwide for its medicinal properties and application in gel-based products such as shampoo,soap,and sunscreen.However,the demand for these gel-based products has led to a surplus production of Aloe vera processing waste.An Aloe vera gel processing facility could generate up to 4000 kg of Aloe vera waste per month.Currently the Aloe vera waste is being disposed to the landfill or used as fertilizer.A sustainable management system for the Aloe vera processing waste should be considered,due to the negative societal and environmental impacts of the currents waste disposal methods.Therefore,this review focuses on various approaches that can be used to valorize Aloe vera waste into value-added products,such as animal and aquaculture feeds,biosorbents,biofuel and natural polymers.Researchers have reported Aloe vera waste for environmental applications biosorbents used for wastewater treatment of various pollutants.Several studies have also reported on the valorization of Aloe vera waste for production of biofuels such as bioethanol,mixed alcohol fuels,biogas and syngas.Aloe vera waste could also be valorized through isolation and synthesis of natural polymers for application in wound dressing,tissue engineering and drug delivery systems.Aloe vera waste valorization was also reviewed through extraction of value-added bioactive compounds such as aloe-emodin,aloin and aloeresin.These value-added bioactive compounds have various applications in the cosmetics(non-steroidal anti-inflammatory,tyrosinase inhibitors)and pharmaceutical(anticancer agent and COVID 19 inhibitors)industry.

Advances in the Study of Chemical Composition and Biological Activities of Aloe Vera Flowers

This review summarizes the main chemical composition of Aloe vera flowers and introduces their antioxidant,anti-aging,skin whitening,skin moisturizing,anti-skin irritation,and anti-skin allergy effects.Suggestions for the application of Aloe v.flowers in cosmetics are provided.

Characterization of yogurt goat milk added Aloe vera and Stevia rebaudiana with functional potential

The search for functional foods with health benefits has increased,and yogurt represents one of these products due to their properties,such as,source of probiotics that favour the gastrointestinal system,contains vitamins,minerals and improves the action of enzymes.Present work investigated bromatological,microbiological,sensorial properties and shelf-life of different yogurt goat milk formulations with Aloe vera and natural sweeteners.The goat yogurt with 99.40%A.vera pulp and 0.60%S.rebaudiana presented the best nutritional composition,being suitable for human consumption representing an innovative product with a great functional potential.The synergy between the ingredients used in the yogurt processing resulted in an innovative product to the market.Goat milk has a lower cost per liter in comparison with cow milk,Aloe vera is accessible due to its fast-vegetative propagation,Stevia Rebaudiana has a great popularity for being a natural sweetener with no calories,and all these products are produced in México.

Anatomy, Histochemistry and Phytochemistry of Leaves in Aloe vera var. chinensis

A multidisciplinary approach-anatomy, histochemistry and phytochemistry-was used to investigate the leaf structure, the content and the storage location of barbaloin in the leaves of Aloe vera L. var. chinensis (Haw.) Berg. Xeromorphic characteristics including secondary thickened epidermal cell walls, thicker cuticle, ambiguous differentiation of spongy and palisade tissues in the chlorenchyma, and well-developed aquiferous tissue could be seen in the leaves. Several large parenchymatous cells were observed at the phloem pole of the first ring of vascular bundles. The secondary ring of vascular bundles in the leaf base and the stomata, which are surrounded by five cells, have some classification significance in this species. The density of vascular bundles, the content of barbaloin and the intensity of histochemical reaction differed among leaf numbers Ll (annual leaf), L2 (biennial leaf), L3 (triennial leaf) and L4 (quadrennial leaf), and in different parts of the leaf. These three factors were highest in the youngest leaf, Ll, and top parts of all the leaves and lowest in the basal parts and the oldest leaf, L4. The density of vascular bundles had a positive correlation to the content of barbaloin. The histochemical results revealed that the small sheath cells that surrounded the bundles might be the location of barbaloin synthesis and the large parenchymatous cells beneath the sheath might be the storage places of this metabolite.

Determination of Barbaloin in Aloe vera L. var. chinensis (Haw.) Berger and Aloe barbadensis Miller by HPLC

A reserved-phase HPLC method was developed for the determination of barbaloin in Aloe vera L. var. chinensis (Haw.) Berger and Aloe barbadensis Miller, and whether there was a close relationship between the contents of barbaloin and their environments in which they were growing was decided. A Hypersil ODS column (4.6 mm×200 mm, 5 μm)was used with a mobile phase of methanol-water (40:60, containing 0.1% acetic acid), the flow rate being 1.0 mL·min -1, detection wavelength at 359 nm, and the column temperature being 30℃. The linear range of barbaloin was between 0.0726 and 0.726 μg with a correlation coefficient of 0.9998 and the regression equation being Y=1.9202×10 6X-1801.9. Barbaloin was stable in methanol in 48 h and the instrument precision was 1.2% while the method precision was 4.9%. The contents of barbaloin of 12 samples ranged from 6.160 to 319.1 μg·g -1. The method developed was fast and simple with good reproducibility. There was high correlation between the contents of barbaloin and their growing environments.

Effects of Aloe vera and sucralfate on gastric microcirculatory changes,cytokine levels and gastric ulcer healing in rats

AIM： To compare the effects of Aloe vera and sucralfate on gastric microcirculatory changes, cytokine levels and gastric ulcer healing. METHODS： Male Spraque-Dawley rats （n=48） were divided into four groups. Group 1 served as control group, group 2 as gastric ulcer group without treatment, groups 3 and 4 as gastric ulcer treatment groups with sucralfate and Aloe vera. The rats from each group were divided into 2 subgroups for study of leukocyte adherence, TNF-α and IL-10 levels and gastric ulcer healing on days 1 and 8 after induction of gastric ulcer by 20% acetic acid. RESULTS： On day 1 after induction of gastric ulcer, the leukocyte adherence in postcapillary venule was significantly （P〈 0.05） increased in the ulcer groups when compared to the control group. The level of TNF-α was elevated and the level of IL-10 was reduced. In the ulcer groups treated with sucralfate and Aloe vera, leukocyte adherence was reduced in postcapillary venule. The level of IL-10 was elevated, but the level of TNF-a had no significant difference. On day 8, the leukocyte adherence in postcapillary venule and the level of TNF-α were still increased and the level of IL-10 was reduced in the ulcer group without treatment. The ulcer treated with sucralfate and Aloe vera had lower leukocyte adherence in postcapillary venule and TNF-α level. The level of IL-10 was still elevated compared to the ulcer group without treatment. Furthermore, histopathological examination of stomach on days 1 and 8 after induction of gastric ulcer showed that gastric tissue was damaged with inflammation. In the ulcer groups treated with sucralfate and Aloe vera on days 1 and 8, gastric inflammation was reduced, epithelial cell proliferation was enhanced and gastric glands became elongated. The ulcer sizes were also reduced compared to the ulcer group without treatment. CONCLUSION： Administration of 20% acetic acid can induce gastric inflammation, increase leukocyte adherence in postcapillary venule and TNF-α level and reduce IL-10 level. Aloe vera treatment can reduce leukocyte adherence and TNF-αlevel, elevate IL-10 level and promote gastric ulcer healing.

Low-temperature green synthesis of boron carbide using aloe vera

The unique structural and physical properties of boron carbide, which make it suitable for a wide range of applications,demands the development of low-cost and green synthesis method. In the present work, the commonly available leaves of aloe vera are hydrothermally treated to form the carbon precursor for the synthesis of boron carbide. The morphological characterization reveals the porous nature of the precursor turning into a tubular structure upon boron carbide formation.The structural characterization by x-ray diffraction and other spectroscopic techniques such as Fourier transform infrared,Raman, photoluminescence and uv-visible near-infrared spectroscopy confirm the formation of boron carbide. The thermogravimetric analysis of the sample is found to exhibit good thermal stability above 500 °C. When the sample is annealed to 600 °C, boron carbide with phase purity is obtained, which is confirmed through XRD and FTIR analyses. The optical emission properties of the sample are studied through CIE plot and power spectrum. Compared with other natural precursors for boron carbide, the aloe vera is found to give a good yield above 50%.

Acute hepatitis induced by an Aloe vera preparation: A case report

AIM: Aloe vera, plant extracts of Aloe barbadensis miller,is widely used in phytomedicine. The first case of acute hepatitis due to this compound was described.METHODS: Description of a clinical case.RESULTS: Hepatitis in a 57-year old female could be linked to the ingestion of Aloe barbadensis miller compounds. The patient's hepatitis resolved completely after discontinuing this medication.CONCLUSION: The case emphasizes the importance of considering phytopharmaceutical over-the-counter drugs as causative agents of hepatitis.

Antifibrotic effect of aloe vera in viral infection-induced hepatic periportal fibrosis

AIM:To investigate the anti-oxidative and anti-fibrotic effects of aloe vera in patients with liver fibrosis.METHODS:Aloe vera high molecular weight fractions(AHM) were processed by patented hyper-dry system in combination of freeze-dry technique with microwave and far infrared-ray radiation.Fifteen healthy volunteers as the control group and 40 patients were included.The patients were randomly subdivided into two equal groups:the conventional group was treated with placebo(starch),and AHM group was treated with 0.15 gm/d AHM,both for 12 consecutive weeks.The patients were investigated before and after treatment.Serum activity of aspartate aminotransferase(AST),alanine aminotransferase(ALT),alkaline phosphatase(ALP),hyaluronic acid(HA),transforming growth factor-β(TGF-β) and matrixmetalloproteinase-2(MMP-2) were determined.The reduced glutathione(GSH) and malondialdehyde(MDA) levels in liver were assayed and the expression of hepatic α-smooth muscle actin(α-SMA) was identified by immunohistochemistry.RESULTS:At the start of the study,the hematoxylin and eosin staining revealed fibro-proliferated bile ductules,thick fibrous septa and dense inflammatory cellular infiltration in the patients before treatment.The use of AHM for 12 wk significantly ameliorated the fibrosis,inhibited the inflammation,and resulted in minimal infiltration and minimal fibrosis compared to the conventional group.The enzyme activities of the liver(ALT,AST and ALP) were attenuated after treatment in both groups,and the decrease in the AHM group was more significant as compared with the conventional group.Similar to the AST,the MDA levels were significantly higher before treatment,and were attenuated after treatment in both groups.In contrast,the hepatic glutathione content in the patients were decreased significantly in the AHM group compared to the controls.The serum levels of the fibrosis markers(HA,TGF-β and MMP-2) were also reduced significantly after treatment.The expression of α-SMA was modified in patients before and after treatment as compared with the normal controls.In the conventional group,there was only thin and incomplete parenchymal α-SMA positive septum joining the thickened centrilobular veins,while in the AHM group,few α-SMA positive cells were present in sinusoid and lobule after treatment.CONCLUSION:Oral supplementation with AHM could be helpful in alleviating the fibrosis and inflammation of hepatic fibrosis patients.

Aloe vera attenuated gastric injury on indomethacin-induced gastropathy in rats

AIM: To evaluate the protective effects of Aloe vera on gastric injury in rats with indomethacin (IMN)-induced gastropathy.

Anti-inflammatory and anti-oxidant effects of aloe vera in rats with non-alcoholic steatohepatitis

BACKGROUND Aloe vera exerts several biological activities,such as,anti-inflammatory,antioxidant,and antimicrobial effects.It was recently shown to reduce insulin resistance and triglyceride level.We hypothesized that aloe vera would have beneficial effects in alleviating non-alcoholic steatohepatitis(NASH)in rats.AIM To examine the therapeutic effects of aloe vera in NASH rats.METHODS All rats were randomly divided into 3 groups(n=6 in each group).Rats in the control group were fed ad libitum with a standard diet for 8 wk.Rats in the NASH group were fed ad libitum with a high-fat high-fructose diet(HFHFD)for 8 wk.Rats in the aloe vera group were fed ad libitum with a HFHFD and aloe vera in dimethylsulfoxide(50 mg/kg)by gavage daily for 8 wk.Liver samples were collected at the end of the treatment period.RESULTS Hepatic malondialdehyde(MDA)levels increased significantly in the NASH group as compared with the control group(377±77 nmol/mg vs 129±51 nmol/mg protein,respectively,P<0.001).Glutathione(GSH)levels were significantly lower in the NASH group than the control group(9±2 nmol/mg vs 24±8 nmol/mg protein,respectively,P=0.001).The expression of interleukin-18 (IL-18), nuclear factor-kappa β, and caspase-3 increased, while peroxisomeproliferator-activated receptor gamma decreased in the NASH group comparedwith the controls. Following aloe vera administration, MDA levels decreased (199± 35 nmol/mg protein) and GSH increased (18 ± 4 nmol/mg protein) markedly.Steatosis, hepatocyte ballooning, lobular inflammation and increased hepatocyteapoptosis were observed in the NASH group. Aloe vera treatment attenuatedthese changes in liver histology.CONCLUSIONAloe vera attenuated oxidative stress, hepatic inflammation and hepatocyteapoptosis, thus improving liver pathology in rats with NASH.

Fast and efficient removal of silver(Ⅰ) from aqueous solutions using aloe vera shell ash supported Ni_(0.5)Zn_(0.5)Fe_2O_4 magnetic nanoparticles

Silver (I) was removed from aqueous environment by aloe vera shell ash supported Ni0.5Zn0.5Fe2O4 magnetic nanoparticles.The adsorbent was characterized by several methods including X-ray diffraction (XRD), scanning electron microscopy (SEM), BETisotherm, vibrating sample magnetometer (VSM) and Fourier transform infrared spectroscopy (FT-IR). To determine the absorptionof silver (I) by this adsorbent, different pH values (2?7), adsorbent dose (0.01?0.5 g), concentrations of Ag+ (50, 100, 200, 300, 500,700 and 1000 mg/L) and exposure time (5?100 min) were experimented. The highest removal efficiency of Ag+ was achieved underoptimum condition (30 min and pH=5). The optimum adsorbent dose was 0.20 g (in 50 mL of 100 mg/L Ag+ solution), whichachieved a removal efficiency of 98.3%. The maximum monolayer adsorption capacity based on the Langmuir isotherm is243.90 mg/g. Characterization results revealed that specific surface area and porous volume were 814.23 m2/g and 0.726 cm3/g,respectively. The experimental data were fitted well with the Langmuir and Freundlich isotherm models. Synthesized adsorbent has desired surface area and adsorptive capacity for silver (I) adsorption in aquatic environment.

Aloe vera Coating Efficiency on Shelf Life of Eggplants at Differential Storage Temperatures

The core objective of instant study was to check the effectiveness of Aloe vera edible coating on postharvest life and physicochemical characteristics of eggplants under different storage temperatures. For this purpose, different formulations of Aloe vera based coating （non-poisonous） was applied at concentration of 0, 0.1%, 0.5%, and 1.0%, respectively on eggplants. The coated eggplants were stored at two different temperatures [10℃ and （30±2）℃] and examined for weight loss, firmness, stem color, shriveling, total soluble solids, pH, acidity, vitamin C, sugar （total sugar, reducing sugar and non-reducing sugar） and N, P, K, Ca and Na for two weeks. The obtained results showed that weight loss, shriveling, total soluble solids, pH, sugar （total sugar and non-reducing sugar） increased and firmness, stem color, acidity, reducing sugar, vitamin C minimized during the storage period. The 0.5% Aloe coating at 10℃ showed significant effect and delayed the changes in above parameters. Aloe vera coating remained almost ineffective in altering nutrient homeostasis （N, P, K, Ca and Na） of eggplants. The optimistic results gained in the current study could additionally investigate in larger market experiments and also could extensive to other tropical/subtropical fruits and vegetables.

Antioxidant responses and salt stress tolerance of Aloe vera irrigated by seawater with different salinity

The variations of antioxidant enzyme activities including superoxide dismutase （SOD： EC 1.15.1.1）, peroxidase （POD： EC 1.11.1.7） and catalase （CAT： EC 1.11.1.6）, lipid peroxidation and major electrolytes in Aloe vera irrigated for three years with seawater having different salinity were studied. The results indicate that POD activity increased significantly at 10% seawater level, whereas decreased at higher seawater levels. The SOD activity decreased with increasing seawater concentration except for treatment with 100% seawater （denoted as T100%） under long-term salt stress. Salinity decreased CAT activity,and increased lipid peroxidation and cell membrane injury. In addition, Ca^2＋ content was high in Aloe irrigated by seawater of low salinity level, but low in Aloe irrigated by seawater of high salinity level. An opposite trend was observed for the effect of seawater on Na^＋ content of plants. K^＋ and Mg^2＋ contents remain relatively stable under various seawater levels, which benefit plant growth.

A Simple Bio-preservation Technique to Increase Shelf Life of Ampalavi Mango Fruits Using Aloe vera Gel

Aloe vera is being identified as a potential medicinal plant for its application in industries as well as traditional usage. The gel obtained from the leaves of A. vera has numerous properties. In this study, using the gel to extend the shelf life of Ampalavi mango fruits was studied. Even sized, uniform coloured, matured Ampalavi cultivar mango fruits were surface cleaned and coated with 33%, 66% and 100% gel, respectively. Results revealed that the ripening was delayed due to the coating. The total soluble solid （TSS）, pH and weight loss were high in uncoated fruits. The mean pH of the pulp from fruits kept as control was 4.94 at 4 d fruit preservation period （FPP） and was slightly increased to 5.43 within 12 d FPP, whereas the minimal pH （4.69 at 4 d FPP and 5.03 at 9 d FPP） was noticed in 100% gel coated fruits. The TSS （brix） was significantly in higher levels （13.67°Bx within 4 d FPP and 20.77°Bx within 12 d FPP） in control fruits, whereas the minimum TSS value was 9.27°Bx and 18.03° Bx within 4 d and 12 d FPP, respectively, recorded from the 100% gel coated fruits in storage. The weight loss percentage （WLP） was significantly （P 〈 0.05） higher in control fruits （8.46%）, whereas the lower WLP （1.13%） was found in 100% gel coated fruits after 12 d of storage. This low-scale gel coating technique prolonged the fruits shelf life by delaying the fruit ripening. This effect has to be further investigated to commercialize the natural product for large scale ready-made application.

Main Polysaccharides Isolated and Quantified of Aloe vera Gel in Different Seasons of the Year

We developed and implemented a methodology that allowed extracting and evaluating high molecular weight polysaccharides present in the gel of Aloe barbadensis Miller. One of the fractions evaluated revealed the presence of high molecular weight carbohydrates (200 kDa) with a behavior similar to that of acemannan and another fraction with compounds of molecular weights between 17 and 47 kDa. We quantified the concentration of acemannan for two different growing periods. The concentration of acemannan in the high molecular weight fraction was 99.97 ppm in the rainy season and 106.03 ppm in the dry season. The concentration of acemannan in the fraction of low molecular weight was 9.364 ppm during the season of greatest rainfall and 26.939 ppm in the dry season.

Electrospun Aloe Vera Extract Loaded Polycaprolactone Scaffold for Biomedical Applications:A Promising Candidate for Corneal Stromal Regeneration

Corneal diseases,the second leading cause of global vision loss affecting over 10.5 million people,underscores the unmet demand for corneal tissue replacements.Given the scarcity of fresh donor corneas and the associated risks of immune rejection,corneal tissue engineering becomes imperative.Developing nanofibrous scaffolds that mimic the natural corneal structure is crucial for creating transparent and mechanically robust corneal equivalents in tissue engineering.Herein,Aloe Vera Extract(AVE)/Polycaprolactone(PCL)nanofibrous scaffolds were primed using electrospinning.The electrospun AVE/PCL fibers exhibit a smooth,bead-free morphology with a mean diameter of approximately 340±95 nm and appropriate light transparency.Mechanical measurements reveal Young’s modulus and ultimate tensile strength values of around 3.34 MPa and 4.58 MPa,respectively,within the range of stromal tissue.In addition,cell viability of AVE/PCL fibers was measured against Human Stromal Keratocyte Cells(HSKCs),and improved cell viability was observed.The cell-fiber interactions were investigated using scanning electron microscopy.In conclusion,the incorporation of Aloe Vera Extract enhances the mechanical,optical,hydrophilic,and biological properties of PCL fibers,positioning PCL/AVE fiber scaffolds as promising candidates for corneal stromal regeneration.

Potential Prevention:Aloe Vera Mouthwash May Reduce Radiation-Induced Oral Mucositis in Head and Neck Cancer Patients

In recent years, more head and neck cancer patients have been treated with radiotherapy. Radiation-induced mucositis is a common and dose limiting toxicity of radiotherapy among patients with head and neck cancers. Patients undergoing radiation therapy for head and neck cancer are also at increased risk of developing oral candidiasis. A number of new agents applied locally or systemically to prevent or treat radiationinduced mucositis have been investigated, but there is no widely accepted prophylactic or effective treatment for mucositis. Topical Aloe vera is widely used for mild sunburn, frostbites, and scalding burns. Studies have reported the beneficial effects of Aloe gel for wound healing, mucous membrane protection, and treatment of oral ulcers, in addition to antiinflammatory, immunomudulation, antifungal, scavenging free radicals, increasing collagen formation and inhibiting collagenase. Herein the author postulates that oral Aloe vera mouthwash may not only prevent radiation-induced mucositis by its wound healing and antiinflammatory mechanism, but also may reduce oral candidiasis of patients undergoing head and neck radiotherapy due to its antifungal and immunomodulatory properties. Hence, Aloe vera mouthwash may provide an alternative agent for treating radiation-induced oral mucositis and candidiasis in patients with head and neck cancers.

Isolation and Purification of Isoaloeresin D and Aloin from Aloe vera by High-speed Counter-current Chromatography

Objective To develop an efficient method to isolate and purify the main components isoaloeresin D and aloin from Aloe vera for its industrial production.Methods High-speed counter-current chromatography was used to isolate isoaloeresin D and aloin in a one-step separation from dried crude extract of A.vera.The biphasic solvent system composed of hexane-ethyl acetate-acetone-water(0.2:5:1.5:5) was used at a flow rate of 1.0 mL/min,while the lipophilic phase was selected as the mobile phase and the apparatus was rotated at 840 r/min.The effluent was detected at 254 nm.Results Isoaloeresin D(53.1 mg) and aloin(106.9 mg) were separated from the crude extract(384.7 mg) with the purities of 98.6% and 99.5%,respectively.Conclusion HSCCC is a powerful technique for isolation and separation of chemical composition from aloe.

Photocrosslinking silver nanoparticles–aloe vera–silk fibroin composite hydrogel for treatment of full-thickness cutaneous wounds

Damage to the skin causes physiological and functional issues.The most effective treatment approach is the use of wound dressings.Silk fibroin(SF)is a promising candidate biomaterial for regulating wound healing;however,its antibacterial properties and biological activity must be further improved.In this study,a photocrosslinking hydrogel was developed to treat full-thickness cutaneous wounds.The composite hydrogel(Ag-AV-SF hydrogel)was prepared by introducing the silver nanoparticles(AgNPs)and aloe vera(AV)as the modifiers.In vitro study exhibited great antibacterial ability,biocompatibility and cell-proliferation and-migration-promoting capacities.It also showed the pH-response releasing properties which release more AgNPs in a simulated chronic infection environment.The healing effect evaluation in vivo showed the healing-promoting ability of the Ag-AV-SF hydrogel was stronger than the single-modifiers groups,and the healing rate of it reached 97.02%on Day 21,higher than the commercial wound dressing,silver sulfadiazine(SS)cream on sale.Additionally,the histological and protein expression results showed that the Ag-AV-SF hydrogel has a greater effect on the pro-healing regenerative phenotype with M2 macrophages at the early stage,reconstructing the blood vessels networks and inhibiting the formation of scars.In summary,the Ag-AV-SF hydrogel developed in this study had good physical properties,overwhelming antibacterial properties,satisfactory biocompatibility and significantly promoting effect on cell proliferation,migration and wound healing.Overall,our results suggest that the Ag-AV-SF hydrogel we developed has great potential for improving the wound healing in clinical treatment.