VIRTUAL LABORATORY ON AUSTRALIAN ABORIGINAL CUSTOMARY MEDICINES

Universities Australia Indigenous Strategy 2017–2020 aims to “ensure all students will encounter and engage with Aboriginal and Torres Strait Islander cultural content as integral parts of their course of study”. Universities across Australia are endeavouring to incorporate Aboriginal and Torres Strait Islander knowledge into their curricula in a respectful, meaningful and sustainable manner. At Macquarie University, situated on Dharug land, the Mudang-Dali (‘to live’ in the Dharug language) Indigenous Connected Curriculum Framework is providing academics with the confidence and support to embed Aboriginal and Torres Strait Islander knowledge, values and philosophies into curriculum. With this support, in Session 1 2020, we developed a laboratory on customary medicines that incorporates a yarning circle, bush food and medicines garden tour, water extraction and chromatographic fractionation of an Australian medicinal plant, and analysis of antioxidant activity (aligned with customary use) of the extract and fractions therein. Designed to be interactive, hands-on and communal, with the implementation of COVID-19 restrictions this laboratory was quickly pivoted into a successful virtual laboratory. This presentation will describe the core components of the laboratory, which interweave Indigenous knowledge and perspectives, and the adaptability of this laboratory for online and face-to-face teaching in the tertiary (and secondary) sectors

Chemical and biological studies of medicinal plants used by Chungtia villagers of Nagaland and Aboriginal people of New South Wales

Empirical thesis.Includes bibliographical references.Chapter 1. Introduction -- Chapter 2. Review on Nagaland medicinal plants -- Chapter 3. Chemical and biological studies of the Nagaland medicinal plant Erythrina stricta -- Chapter 4. NSW medicinal plant : literature review and chemical and biological studies -- Chapter 5. Summary, conclusions and future directions.This PhD study was based on the ethnomedicinal knowledge of the Chungtia Indigenous community of Nagaland, India and Aboriginal people of New South Wales (NSW), Australia. It follows former investigations of the Macquarie University’s Indigenous Bioresources Research Group on first hand documentation of medicinal plants used by the Chungtia villagers and first hand and published accounts of medicinal plants used by Aboriginal people of NSW for the treatment of skin related ailments including sores,wounds and skin infections. The overall objective of this study was to conduct chemical and biological investigations on medicinal plants used for the treatment of skin related conditions by the Chungtia villagers of Nagaland and Aboriginal people of NSW.A comprehensive literature review on 135 Chungtia medicinal plants documented by firsthand interviews was conducted. In addition, an updated literature review on plants used for the treatment of sores, wounds and skin infections was performed. The first hand information of the medicinal plants was compared with published reports of ethnobotanical and ethnomedicinal uses as well as chemical and biological studies worldwide. The review identified eleven medicinal plants used for the treatment of skin related diseases with none or limited reports of chemical and/or biological studies. These therefore have potential for further studies. One of these plants, Erythrina stricta Roxb. (Fabaceae), used for the treatment of skin infections, eczema and contact dermatitis by Chungtia villagers, was selected for detailed chemical and biological investigations.Bark of E. stricta was sequentially extracted with n-hexane, dichloromethane, ethyl acetate, methanol and water and the extracts were assayed against the bacterial strains methicillin sensitive Staphylococcus aureus, methicillin resistant S. aureus, multidrug resistant S. aureus, antibiotic sensitive Escherichia coli and Pseudomonas aeruginosa and the fungal strain Candida albicans. The most significant antimicrobial activity was observed with the dichloromethane, n-hexane and ethyl acetate extracts, with MIC values of 7.81μg/mL, 125 μg/mL and 125 μg/mL against a methicillin sensitive strain of S. aureus. The extracts were also screened for antioxidant activity by DPPH (2,2-diphenyl-1-picrylhydrazyl) free radical scavenging and ferric reducing antioxidant power (FRAP) assay methods. All the extracts showed positive responses to the antioxidant assays. GC-MS analysis of the n-hexane extract identified twelve compounds, including the bioactive compounds caryophyllene oxide (16.31%), β-caryophyllene (9.06%), β-selinene (7.06%),α-selinene (6.86%), selin-11-en-4-α-ol (6.80%), α-copaene (3.31%) and α-eudesmol(4.60%). These compounds have been reported for having antimicrobial (β-caryophyllene,caryophyllene oxide, α-eudesmol, α-selinene, β-selinene, α-copaene and δ-cadenine) and anti-inflammatory (α-copaene, β-caryophyllene, caryophyllene oxide and δ-cadenine) activities. Fractionation of the dichloromethane extract by normal phase silica gel column chromatography yielded eight active fractions that showed antibacterial activity against the methicillin sensitive strain of S. aureus with MIC values ranging from 15.6 μg/mL to 1mg/mL. Purification of the active fractions using different chromatographic techniques ledto the isolation of seven antimicrobial and antioxidant compounds; erynone, wighteone,alpinum isoflavone, luteone, obovatin, erythrinassinate B and isovanillin. Erynone wasidentified as a novel compound and this is the first report of isolation of luteone, obovatinand isovanillin from the genus Erythrina and the first report of isolation of wighteone and erythrinassinate B from E. stricta.A literature review of medicinal plants used by Aboriginal people of NSW for skin related ailments was conducted and thirty two plants were identified with none or limited reports on chemical and biological studies. Following this review, Acacia falcata, Acacia implexa, Cassytha glabella, Eucalyptus haemastoma, Hibbertia scandens, Smilax glyciphylla,Sterculia quadrifida and Syncarpia glomulifera were selected for chemical and biological studies. 70% aqueous ethanolic extracts obtained from the eight selected species were screened for antibacterial and antioxidant activities. Antibacterial activity assays of the extracts were conducted against methicillin sensitive, methicillin resistant and multidrug resistant strains of S. aureus, E. coli and P. aeruginosa using the MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide] microdilution assay. All the extracts apart from S. glyciphylla and S. quadrifida possessed antibacterial activity against all three strains of S. aureus. S. glyciphylla showed activity against only methicillin sensitive S. aureus and S. quadrifida did not show any activity against any bacterial strains. S. glomulifera was identified with having the most active plant extract with an MIC of 7.81μg/mL, followed by E. haemastoma with MIC 62.5 μg/mL and A. implexa with MIC 125μg/mL. Qualitative and quantitative phytochemical screening of the extracts was also conducted. This is the first report of antibacterial activity of A. falcata, A. implexa, C.glabella, E. haemastoma, H. scandens and S. glomulifera against methicillin resistant strains of S. aureus.Antioxidant activity of the eight NSW plant extracts was evaluated by DPPH free radical scavenging, ABTS [2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid)] radical scavenging activity and FRAP assay methods. E. haemastoma, A. falcata and A. implexa possessed high antioxidant activity, with IC50 values of 51.99 ± 1.17 μg/mL, 130.20 ± 5.37and 217.03 ± 3.80, respectively. Qualitative phytochemical screening identified the presence of terpenoids, flavonoids, steroids, alkaloids, saponins, tannins and anthraquinone glycoside classes of compounds within the extracts. The highest amount of total phenolic and condensed tannin contents were found for E. haemastoma, followed by A. implexa. Acacia falcata contained the highest amount of total flavonoid content, with E. haemastoma and C. glabella also containing a high flavonoid content. A significant correlation was observed between the antioxidant properties and the total phenolic and flavonoid contents, which suggested that the phenolic and flavonoid type of compounds present in the extracts are the major contributors to their antioxidant properties. This is the first report of antioxidant activity studies for A. falcata, A. implexa, C. glabella, E.haemastoma, H. scandens, S. quadrifida and S. glomulifera.The 70% aqueous ethanolic extract of S. glomulifera was partitioned with n-hexane, dichloromethane, ethyl acetate, n-butanol and water. The partitions were screened for antibacterial activity against methicillin sensitive, methicillin resistant and multidrug resistant strains of S. aureus, E. coli and P. aeruginosa. The n-hexane partition showed the greatest activity with an MIC of 7.81 μg/mL against all three strains of S. aureus. GCMS analysis of the n-hexane partition identified twenty-four phytochemicals that included the well-known antimicrobial, antioxidant and anti-inflammatory compoundsα-phellandrene, aromadendrene, α-copaene, geranial, globulol, terpinene-4-ol and spathulenol.The identification of antibacterial and antioxidant activities and bioactive constituents from E. stricta and the NSW medicinal plants provides support for their traditional medicina luses by the Chungtia community of Nagaland and Aboriginal communities of NSW for the treatment of skin related ailments and increases the knowledge on these relatively unexplored plants.Mode of access: World wide web1 online resource (xvii, 225 pages) illustrations (some colour

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.13 page(s

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.14 page(s

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 g/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 7.8 µg/mL, 125 µg/mL, and 125 µg/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 125 µg/mL and 1 mg/mL respectively. GC-MS analysis of the n-hexane extract showed the presence of the antibacterial and antifungal compounds β-caryophyllene, caryophyllene oxide, α-selinene, β-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 1.88 µg, 1.88 µg and 3.75 µg, 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.11 page(s