Phytochemical Profile and Antibacterial and Antioxidant Activities of Medicinal Plants Used by Aboriginal People of New South Wales, Australia.

Aboriginal people of Australia possess a rich knowledge on the use of medicinal plants for the treatment of sores, wounds, and skin infections, ailments which impose a high global disease burden and require effective treatments. The antibacterial and antioxidant activities and phytochemical contents of extracts, obtained from eight medicinal plants used by Aboriginal people of New South Wales, Australia, for the treatment of skin related ailments, were assessed to add value to and provide an evidence-base for their traditional uses. Extracts of Acacia implexa, Acacia falcata, Cassytha glabella, Eucalyptus haemastoma, Smilax glyciphylla, Sterculia quadrifida, and Syncarpia glomulifera were evaluated. All extracts except that of S. quadrifida showed activity against sensitive and multidrug resistant strains of Staphylococcus aureus with minimum inhibitory concentration values ranging from 7.81 to 1000 µg/mL. The sap of E. haemastoma and bark of A. implexa possessed high total phenolic contents (TPC) and strong DPPH radical scavenging abilities. A positive correlation was observed between TPC and free radical scavenging ability. GC-MS analysis of the n-hexane extract of S. glomulifera identified known antimicrobial compounds. Together, these results support the traditional uses of the examined plants for the treatment of skin related ailments and infections by Aboriginal people of New South Wales, Australia.

Antimicrobial and antioxidant activity and chemical characterisation of Erythrina stricta Roxb. (Fabaceae).

ETHNOPHARMACOLOGICAL RELEVANCE: The bark of Erythrina stricta Roxb. (Fabaceae) has been used in Indian indigenous systems as a remedy for rheumatism, stomach-ache, asthma, dysentery, contact dermatitis, eczema and skin infections. However, there have been limited phytochemical or biological studies on the bark of E. stricta and there are no studies that align with its traditional medicinal uses. AIM OF THE STUDY: The aim of this study was to assess the antimicrobial and antioxidant activity of the stem bark of E. stricta to support its topical use in the treatment of contact dermatitis, eczema and skin infections and to isolate and identify any bioactive compounds. MATERIALS AND METHODS: MTT microdilution and disc diffusion assays were used to determine the antimicrobial activities of n-hexane, dichloromethane, ethyl acetate, methanol and water extracts of the bark of E. stricta. Column and preparative thin layer chromatography were used for the purification of the dichloromethane extract. The structures of the compounds isolated were elucidated by extensive 1D and 2D NMR spectroscopic techniques and comparison with published data. The antioxidant activities of the extracts were determined by DPPH free radical scavenging and FRAP assays and the antioxidant activity of the pure compounds by dot-blot and DPPH staining methods. RESULTS: The dichloromethane, ethyl acetate, and n-hexane extracts showed the most significant activity with MIC values of 7.8µg/mL, 125µg/mL, and 125µg/mL against a sensitive strain of Staphylococcus aureus. The dichloromethane and ethyl acetate extracts also showed significant activity against Candida albicans with MIC values of 125µg/mL and 1mg/mL respectively. GC-MS analysis of the n-hexane extract showed the presence of the antibacterial and antifungal compounds ß-caryophyllene, caryophyllene oxide, α-selinene, ß-selinene, selin-11-en-4-α-ol, α-copaene and δ-cadenine. Phytochemical studies of the dichloromethane extract led to the isolation of the novel compound erynone (1), together with six known compounds; wighteone (2), alpinum isoflavone (3), luteone (4), obovatin (5), erythrinassinate B (6) and isovanillin (7). Luteone (4) exhibited the most significant antibacterial activity with minimum inhibitory quantity (MIQ) values of 1.88µg, 1.88µg and 3.75µg, respectively, against sensitive (MSSA) and resistant strains (MRSA and MDRSA) of S. aureus using a TLC bioautography assay. Erynone (1) exhibited the greatest DPPH free radical scavenging activity. CONCLUSIONS: Seven compounds, including a new chromanone, were isolated from the antimicrobial dichloromethane extract of the stem bark of E. stricta. Six of the seven compounds showed antibacterial and/or antioxidant activities. These findings provide support for the customary (traditional and contemporary) use of E. stricta bark for the treatment of skin and wound infections.

An ethnobotanical study of medicinal plants of Chungtia village, Nagaland, India.

ETHNOPHARMACOLOGICAL RELEVANCE: Traditional medicinal plant knowledge is an integral and very important part of Indigenous cultures worldwide. For many communities there is a great urgency in recording this knowledge in written form. This is the first ethnobotanical report of medicinal plant knowledge of the Nagaland Ao tribe of Chungtia village and is an important step in the preservation of this culturally and medicinally significant knowledge. AIM OF THE STUDY: The aim of the presented work was to perform an ethnobotanical study on plants of medicinal and other significance to the Chungtia villagers of Nagaland, North East India. MATERIALS AND METHODS: Ethnobotanical data were collected from traditional practitioners and Elders of Chungtia village by means of open group discussions and semi-structured interviews of groups and individuals using questionnaires. The interviews were also recorded in an audio format in the local Mongsen language. The gathered ethnobotanical knowledge was compared with reported ethnobotanical usages worldwide and reported biological properties and phytochemical studies relevant to the Chungtia villagers׳ applications. RESULTS: A total of 135 plant species of 69 families and 123 genera were recorded for medicinal and household maintenance applications. Those applications were grouped into 13 categories based on Chungtia villagers׳ classification system. The families most represented were Asteraceae, Euphorbiaceae and Solanaceae. The most reported uses were for gastrointestinal problems, followed by dermatological problems. The most commonly used plant parts were leaves, followed by fruits and stems and they were most commonly administered as a paste, decoction, infusion, juice or poultice, or taken orally with no preparation. There was strong agreement among the informants as to the usages of the plants (informant consensus factor 0.80-0.91). The use value of 6 for Cassia floribunda, Dolichos lablab, Hedyotis scandens, Phyllanthus urinaria and Rhus javanica indicated these are the most important species. Forty four of the 135 plants had a fidelity level of 100%. CONCLUSION: This study has helped to document and preserve in written format important traditional plant knowledge of 135 plants of the Chungtia villagers, assisting them in the continued preservation of their cultural values.

Novel flavonoid glycosides from the bulbs of Urginea indica Kunth.

Three novel flavonoid glycosides, 5,6-dimethyoxy-3',4''-dioxymethylene-7-O-(6''-beta-D-glucopyranosyl-beta-D-glucopyranosyl) flavanone (1), 5,4'-dihydroxy-3-O-alpha-L-rhamnopyranosyl-6-C-glucopyranosyl-7-O-(6''-para-coumaroyl-beta-D-glucopyranosyl) flavone (2) and 5,4'-dihydroxy-3-O-(2'''''-beta-glucopyranosyl-alpha-L-rhamnopyranosyl)-6-C-glucopyranosyl-7-O-(6''-para-coumaroyl-beta-D-glucopyranosyl) flavone (3) were isolated from the 1-butanol soluble fraction of the bulbs of the plant Urginea indica (Indian squill). The structures of the compounds were elucidated on the basis of spectral analysis, including homo- and heteronuclear correlation NMR experiments (COSY, NOESY, HSQC and HMBC) and mass spectra.