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Concept: Henna


The use of Lawsonia inermis L. (henna) for medicinal and cosmetic purposes is inextricably linked to ancient and modern cultures of North Africa and Asia. Literature and artwork indicates that L. inermis played an important holistic role in the daily lives of some ancient cultures, providing psychological and medicinal benefits, as well as being used for personal adornment. Although henna was historically applied to the hands and feet to protect against fungal pathogens and to hair to combat lice and dandruff, other traditional uses include the treatment of liver and digestive disorders, reduction of tissue loss in leprosy, diabetic foot disorders and ulcers.

Concepts: Anthropology, Henna, Lawsonia


Concerns about health issues and environmental pollution stimulate research to find new health and hygiene related products with healing properties and minimum negative effect on the environment. Development of new, natural antibacterial agents has become one of the most important research areas to combat some pathogens such as Gram- positive and Gram-negative bacteria, fungi, algae, yeast, and some microorganisms which cause serious human infections. Lawsonia Inermis (henna) leaf extracts for preparation of antibacterial poly(ethylene oxide) (PEO) and poly(vinyl alcohol) (PVA) nanofibers via electrospinning technique were investigated. PEO and PVA based electrospun fibers containing henna extract were verified by the appearance of FTIR peaks corresponding to the pure extract. Our study demonstrates that 2.793 wt.% Li in PVA and PEO based solutions showed bactericidal effects against Staphylococcus aureus and bacteriostatic action to Escherichia coli. Concentrations of henna leaf extract strongly impacted antibacterial activities against both bacteria. Henna leaves have a great potential to be used as a source of a potent eco-friendly antimicrobial agent.

Concepts: Photosynthesis, Bacteria, Microbiology, Staphylococcus aureus, Escherichia coli, Tea tree oil, Henna, Chloramphenicol


Lawsonia inermis (Lythraceae) known as henna is one of the most popular and ancient plants used in cosmetics and hair dying. It is cultivated for its leaves but other parts such as seeds, flowers, stem bark and roots are also used in traditional medicine for millennia. Henna tattoo paste also proved to be beneficial for wound healing and in several skin diseases suggesting potent anti-inflammatory activity. To evaluate henna anti-inflammatory activity, 31 compounds, including three 1,5-diphenylpent-3-en-1-yne derivatives, lawsochylin A-C and three methyl naphthalene carboxylates, lawsonaphthoate A-C, were isolated from the stems and leaves of henna utilizing a bioassay-guided fractionation. The structures of the compounds were elucidated by spectroscopic data. Two compounds, lawsochylin A and lawsonaphthoate A showed potent anti-inflammatory activity by inhibition of superoxide anion generation (IC(50)=1.80 and 1.90μg/ml) and elastase release (IC(50)=1.58 and 3.17μg/ml) of human neutrophils in response to fMLP or cytochalasin B. Moreover, the known compounds, luteolin, apigenin, 4S-4-hydroxy-α-tetralone, and 2-butoxysuccinic acid, also showed potent inhibition of superoxide anion generation (IC(50)=0.75-1.78μg/ml) and elastase release (IC(50)=1.62-3.61μg/ml).

Concepts: Henna, Lythraceae, Tattoo, Mehndi, Diwali, Lawsonia


A simple and efficient procedure was employed for the synthesis of N'-(1,4-naphtho-quinone-2-yl) isonicotinohydrazide (NIH) by the reaction of 2-hydroxy-1,4-naphthaquinone (lawsone) and isonicotinoyl hydrazine in methanol using ultrasonic irradiation. Lawsone is the principal dye, isolated from the leaves of henna (Lawsonia inermis). Structural modification was done on the molecule aiming to get a more active derivative. The structure of the parent compound and the derivative was characterized by elemental analyses, infrared, electronic, (1)H, (13)C NMR and GC-MS spectra. The fluorescence spectral investigation of the compound was studied in DMSO and ethanol. Single crystal X-ray diffraction studies reveal that NIH crystallizes in monoclinic space group. The DNA cleavage study was monitored by gel electrophoresis method. The synthesized compound was found to have significant antioxidant activity against DPPH radical (IC50=58 μM). The in vitro cytotoxic studies of the derivative against two human cancer cell lines MCF-7 (human breast cancer) and HCT-15 (human colon carcinoma cells) using MTT assay revealed that the compound exhibited higher cytotoxic activity with a lower IC50 value indicating its efficiency in killing the cancer cells even at low concentrations. These results suggest that the structural modifications performed on lawsone could be considered a good strategy to obtain a more active drug.

Concepts: DNA, Cancer, Breast cancer, X-ray, Molecule, Colorectal cancer, Squamous cell carcinoma, Henna


Background: The use of temporary henna tattoos has increased dramatically in recent years, especially in children and adolescents. To obtain a darker colour and prolong the life of the tattoo, red henna, a plant-derived substance, is typically added to para-phenylenediamine (PPD). The mixture is called temporary black henna tattoo (TBHT). Because of its molecular characteristics, PPD can induce skin sensitization that may cause various clinical manifestations with successive exposures, among which the most common is allergic contact dermatitis (ACD). This report describes two paediatric cases of PPD sensitization and ACD after the exposure to TBHT and summarizes the literature on this emerging clinical problem. Case Presentation: We describe two cases of childhood-onset ACD that occurred 2 and 10 days, respectively, after the application of a TBHT during the summer holidays. Patch tests showed an evident positive response to 1% PPD in both cases. Sensitization to PPD occurred in the first case because a previous henna tattoo did not result in overt symptoms; in the second case, the reaction occurred after the same tattoo was retouched. In both cases, hypopigmentation persisted and both the patients and their families were advised to avoid further contact with PPD-containing materials and substances that could lead to cross-reactions. Conclusions: Sensitization to PPD is a growing phenomenon in children. The most common cause appears to be exposure to TBHT in which PPD might be present at unknown or high concentrations. Once sensitization occurs, patients may experience severe clinical symptoms which can present with a persistent hypopigmentation when they are re-exposed to substances that contain or cross-react with PPD. Given the widespread use of PPD, TBHT could adversely affect the daily life of paediatric patients; thus, for this reason, this practice as a fashion accessory must be discouraged. In addition, it is extremely important to provide scientific information on the risks of TBHT to consumers, especially to adolescents and to the parents of younger children to prevent PPD sensitization.

Concepts: Contact dermatitis, P-Phenylenediamine, Henna, Body modification, Tattoo, Body art, Mehndi, Diwali


Paraphenylenediamine (PPD) is an amine that is mainly used as an ingredient in hair dyes and henna tattoos. The incidence of allergic contact dermatitis to PPD is increasing, particularly in younger patients. In this article, we review the main sources of PPD and the substances with which it can interact and present a practical algorithm for diagnosing and treating suspected cases of PPD allergy.

Concepts: Hypersensitivity, Eczema, Dermatitis, Contact dermatitis, Henna


Risk factors for p-phenylenediamine (PPD) sensitization include the use of hair dyes, the application of temporary black henna tattoos, working as a hairdresser, and, possibly, exposure to hair dye pretests.

Concepts: Henna, Body modification, Hairdressing, Hair color


The fast development of multi-drug resistant (MDR) organisms increasingly threatens global health and well-being. Plant natural products have been known for centuries as alternative medicines that can possess pharmacological characteristics, including antimicrobial activities. The antimicrobial activities of essential oil (Calli oil) extracted from the Calligonum comosum plant by hydro-steam distillation was tested either alone or when combined with lawsone, a henna plant naphthoquinone, against MDR microbes. Lawsone showed significant antimicrobial activities against MDR pathogens in the range of 200-300 µg/mL. Furthermore, Calli oil showed significant antimicrobial activities against MDR bacteria in the range of 180-200 µg/mL, Candida at 220-240 µg/mL and spore-forming Rhizopus fungus at 250 µg/mL. Calli oil’s inhibition effect on Rhizopus, the major cause of the lethal infection mucormycosis, stands for 72 h, followed by an extended irreversible white sporulation effect. The combination of Calli oil with lawsone enhanced the antimicrobial activities of each individual alone by at least three-fold, while incorporation of both natural products in a liposome reduced their toxicity by four- to eight-fold, while maintaining the augmented efficacy of the combination treatment. We map the antimicrobial activity of Calli oil to its major component, a benzaldehyde derivative. The findings from this study demonstrate that formulations containing essential oils have the potential in the future to overcome antimicrobial resistance.

Concepts: Bacteria, Microbiology, Plant, Fungus, Essential oil, Oil, Oils, Henna


Three new benzenoid derivatives, lawsoinermone (1), inermidioic acid (2), and inermic acid (3) have been isolated from the aerial part of Lawsonia inermis, together with 11 known compounds (4-14). The structures of three new compounds were determined through spectroscopic and MS analyses. Compounds 1, 4-6, 13 and 14 were evaluated for inhibition of nitric oxide production in LPS-stimulated product of nitrite in RAW 264.7 cells with IC50 values of 6.12, 16.43, 18.98, 9.30, 9.30 and 14.90 μg/mL, respectively.

Concepts: Ammonia, Neurotransmitter, Nitric oxide, Nitric acid, Henna, Lawsonia


Wound healing characteristics of some plant extracts have been well known for many years, and they have been utilized for such applications in traditional way. Recently electrospun nanofibrous mats showed promising properties for tissue engineering and especially for skin repair. It is expected that incorporation of plant extracts into such structures could provide higher performance and synergistic effect for biomedical and wound healing applications. The final purpose of this study is to fabricate chitosan based nanofiber mats loaded with a traditional plant extract of Lawsonia inermis (Henna) leaves to enhance the antibacterial efficacy and wound healing of the precursor nanofibers. The morphology, structure, mechanical properties and swelling and weight loss degree of the electrospun nanofibers have been investigated in this study. Antibacterial activity, cell biocompatibility evaluations and in vivo wound healing activity of the abovementioned mats were also studied. The FESEM images of Henna leaves extract-loaded nanofibers proved that homogeneous, smooth and defect free nanofibers of 64-87nm in diameter have been prepared. Presence of Henna extract in the electrospun fibers was approved by Fourier Transform Infrared spectroscopy. Incorporation of Henna extract into the nanofiber mats exhibited significant synergistic antibacterial activity against bacterial cells. It was well supported by the results of cell viability and proliferation of human foreskin fibroblast cells on the prepared scaffolds. Therefore, the results of this work showed that Henna leaves extract incorporated chitosan nonwoven mats have a great potential to be used as the biodegradable, biobased and antibacterial wound healing dressings.

Concepts: Spectroscopy, Bacteria, Wound healing, Extracellular matrix, Fibroblast, Fourier transform, Fourier transform spectroscopy, Henna