Plants of the genus Terminalia are amongst the most widely used plants for traditional medicinal purposes worldwide. Many species are used for their antibacterial, antifungal, antiprotozoal, antiviral, antidiarrhoeal, analgesic, antimalarial, antioxidant, antiinflammatory and anticancer activities. Wound healing and cardiovascular effects have also been credited to some species. Many Terminalia species have multiple beneficial effects for multiple diseases and ailments. Indeed, the Indian species Terminalia chebula is known as the king of plants in Ayurveda due to its broad range of medicinal uses. However, apart from the reported ethnopharmacological uses of many Terminalia species, surprisingly few studies have rigorously examined this important genus for their medical properties/mechanisms and phytochemistry. This is likely due to the high tannin content common to many Terminalia species and the perception that these tannins may be responsible for much of their beneficial properties. As the complexities of tannins make them poor candidates for drug design, most interest in Terminalia species has been for their pharmacognostic and nutraceutical value and they have often been overlooked as potentials for drug discovery. However, recent reports have identified many other interesting phytochemicals and demonstrated that these may be responsible for several of the reported bioactivities of the Terminalia species used in traditional medicinal systems. The last decade has seen a large increase in the number of studies into the use of Terminalia species as therapeutic agents. Several species used in Ayurvedic medicine (Terminalia arjuna, Terminalia bellerica, Terminalia catappa, T. chebula) in particular have received much recent attention. Similarly, recent reports have also highlighted the medicinal potential of species from Africa, Australia and the Americas. The aim of this report is to summarise the recent research into the medicinal properties, phytochemistry and therapeutic mechanisms of Terminalia species and thus to highlight and direct future areas of research into the medicinal activities of this important genus.

The discovery of penicillin nearly 90 years ago revolutionized the treatment of bacterial disease. Since that time, numerous other antibiotics have been discovered from bacteria and fungi, or developed by chemical synthesis and have become effective chemotherapeutic options. However, the misuse of antibiotics has lessened the efficacy of many commonly used antibiotics. The emergence of resistant strains of bacteria has seriously limited our ability to treat bacterial illness, and new antibiotics are desperately needed. Since the discovery of penicillin, most antibiotic development has focused on the discovery of new antibiotics derived from microbial sources, or on the synthesis of new compounds using existing antibiotic scaffolds to the detriment of other lines of discovery. Both of these methods have been fruitful. However, for a number of reasons discussed in this review, these strategies are unlikely to provide the same wealth of new antibiotics in the future. Indeed, the number of newly developed antibiotics has decreased dramatically in recent years. Instead, a reexamination of traditional medicines has become more common and has already provided several new antibiotics. Traditional medicine plants are likely to provide further new antibiotics in the future. However, the use of plant extracts or pure natural compounds in combination with conventional antibiotics may hold greater promise for rapidly providing affordable treatment options. Indeed, some combinational antibiotic therapies are already clinically available. This study reviews the recent literature on combinational antibiotic therapies to highlight their potential and to guide future research in this field.

This study was undertaken to evaluate the protective efficacy of the antioxidants vitamin E and Trolox (a water-soluble vitamin E derivative) against the toxicity of microcystin-LR (MC-LR), Microcystis aeruginosa aqueous extract (CE), and a reference toxin, menadione sodium bisulfite (MSB), in Artemia franciscana nauplii. This was achieved by using the well-established brine shrimp bioassay. The experiment was conducted in 2 stages, with (1) 12-h mortality time course and (2) LC50 determination for 12- and 24-h exposures. Treatments consisted of MC-LR, CE, and MSB alone and with 4-h pretreatments of either vitamin E or Trolox. Sensitivity of A. franciscana nauplii with 24-h LC50 values of 11 (10.1-12.1) microg/ml for MSB and 9.5 (8.8-10.4) microg/ml for MC-LR were in general agreement with values reported for Artemia sp. Both antioxidant pretreatments resulted in significant reductions in mortality of approximately 50% at 9 h postexposure when challenged by either 40 microg/ml MC-LR or 20 microg/ml MSB. In contrast, the antioxidant pretreatments offered little to no protection from CE, suggesting that other uncharacterized bioactive compounds contributed to overall toxicity. The described bioassay is easily accessible, inexpensive, rapid, and complies with animal ethics guidelines of many countries, and thus provides a potential alternative to the mouse bioassay for the initial screening for chemoprotectants against MC-LR toxicity.

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A wide variety of herbal remedies are used in traditional African medicine to treat rheumatoid arthritis (RA) and inflammation. Thirty-four extracts from 13 South African plant species with a history of ethnobotanical usage in the treatment of inflammation were investigated for their ability to control two microbial triggers for RA (Proteus mirabilis and Proteus vulgaris). Twenty-nine of the extracts (85.3 %) inhibited the growth of P. mirabilis and 23 of them tested (67.7 %) inhibited the growth of P. vulgaris. Methanol and water extracts of Carpobrotus edulis, Lippia javanica, Pelargonium viridflorum, Ptaeroxylon obliquum, Syzygium cordatum leaf and bark, Terminalia pruinoides, Terminalia sericea, Warburgia salutaris bark and an aqueous extract of W. salutaris leaf were effective Proteus inhibitors, with MIC values <2,000 μg/ml. The most potent extracts were examined by Reverse phase high performance liquid chromatography and UV-Vis spectroscopy for the presence of resveratrol. Only extracts from T. pruinoides and T. sericea contained resveratrol, indicating that it was not responsible for the anti-Proteus properties reported here. All extracts with Proteus inhibitory activity were also either non-toxic, or of low toxicity in the Artemia nauplii bioassay. The low toxicity of these extracts and their inhibitory bioactivity against Proteus spp. indicate their potential for blocking the onset of rheumatoid arthritis.

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Introduction:Multiple sclerosis is an autoimmune disease which can be triggered in genetic susceptible individuals by Acinetobacter spp. and Pseudomonas aeruginosa infections. Terminalia ferdinandiana (Kakadu plum) fruit has documented therapeutic properties as a general antiseptic agent. Extracts prepared from the leaves have also been shown to block several microbial triggers of autoimmune inflammatory diseases. This study examines the ability of Kakadu plum fruit extracts to inhibit some microbial triggers of multiple sclerosis. Methods: T. ferdinandiana fruit solvent extracts were investigated by disc diffusion assay against reference and clinical strains of A.baylyi and P. aeruginosa. Their MIC values were determined to quantify and compare their efficacies. Toxicity was determined using the Artemia franciscana nauplii bioassay. Active extracts were analysed by non-targeted HPLC-QTOF mass spectroscopy (with screening against 3 compound databases) and by GC-MS (with screening against 1 compound databases) for the identification and characterisation of individual components in crude plant extracts. Results: Methanolic, aqueous and ethyl acetate T. ferdinandiana leaf extracts displayed potent antibacterial activity in the disc diffusion assay against the bacterial triggers of multiple sclerosis (A.baylyi and P. aeruginosa). The methanol and ethyl acetate extracts had the most potent growth inhibitory activity, with MIC values less than 1000 µg/ ml against A. baylyi and P. aeruginosa (both reference and clinical strains). In comparison, the water extract was substantially less potent. Neither the chloroform nor hexane extracts inhibited the growth of any of the bacterial strains tested. All T. ferdinandiana fruit extracts were nontoxic in the Artemia fransiscana bioassay. Non-biased phytochemical analysis of the ethyl acetate extract revealed only low levels of the tannins gallic acid and chebulic acid and no other tannins. Conclusion: The low toxicity of the T. ferdinandiana fruit extracts and their potent inhibitory bioactivity against the bacterial triggers of multiple sclerosis indicates their potential as medicinal agents in the treatment and prevention of this disease. Phytochemical studies indicate that this activity is likely to be due to phytochemicals other than tannins.

A wide variety of herbal remedies are used in traditional African medicine to treat inflammatory disorders, including some autoimmune diseases. Thirty-four extracts from 13 South African plant species traditionally used for the treatment of inflammation were investigated for their ability to control a microbial trigger for ankylosing spondylitis (Klebsiella pneumoniae). Twenty-six of the extracts (76.5%) inhibited the growth of K. pneumoniae. Methanol and water extracts of Ballota africana, Carpobrotus edulis leaves, Kigellia africana, Lippia javanica, Pelargonium fasiculata, Syzygium cordatum (including bark), Terminalia pruinoides and Terminalia sericea were effective K. pneumoniae inhibitors, with MIC values <1000 µg/ml. The roots of Tulbaghia violaceae and bark from Warburgia salutaris also demonstrated efficacy. The most potent extracts were examined by RP-HPLC and UV-Vis spectroscopy for the presence of resveratrol. Methanolic extracts of B. africana, C. edulis leaves, L. javanica, T. pruinoides and T. sericea, as well as aqueous B. africana, T. pruinoides and T. sericea extracts, displayed peaks with retention times and UV-Vis spectra consistent with the presence of resveratrol. Resveratrol was generally a minor component, indicating that resveratrol was not solely responsible for the anti-Klebsiella growth inhibitory properties. Plant extracts with K. pneumoniae inhibitory activity were either non-toxic, or of low toxicity in the Artemia (brine shrimp) nauplii bioassay. Their low toxicity and antibiotic bioactivity against K. pneumoniae indicate their potential for both preventing the onset of ankylosing spondylitis and minimising its symptoms once the disease is established.