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Chemical structures of methyl ketone terpenes and main constituents of Suregada zanzibariensis essential oil. High quality figures are available online.
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In traditional African communities, repellent volatiles from certain plants generated by direct burning or by thermal expulsion have played an important role in protecting households against vectors of malaria and other diseases. Previous research on volatile constituents of plants has shown that some are good sources of potent mosquito repellents....
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The prevalence of mosquito-borne diseases is one of the world's most important health problems. Therefore, it is necessary to prevent mosquito-borne diseases and improve public health by controlling mosquitoes. Mosquitoes in the larval stage are attractive targets for pesticides because mosquitoes breed in water, which makes it easy to deal with th...
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... (S)-(+)carvone (C 10 H 14 O) is a liquid found mainly in caraway and dill seed oils and it is mainly used by the cosmetic industry. (1S)-(−)-verbenone (C 10 H 14 O) is also a liquid and it is one of the main components of the essential oil of Suregada zanzibariensis leaves [32] and it finds applications, among others, in the production of anti-ischemic materials [33]. The last chiral dopant is (3aR)-(+)-sclareolide (C 16 H 26 O 2 ), which is a powder derived from various plants, including Salvia sclarea, and it is used in the perfume industry and in the syntheses of some bioactive compounds [34]. ...
Helical twists exist in liquid crystals as a result of the addition of chiral dopants or boundary conditions and play a role in several liquid-crystal phenomena and devices. To date, various methodologies have been explored, albeit with varying degrees of precision and complexity, often resulting in the measurement of just one parameter, such as helical sense. However, a consensus on the optimal technique remains elusive. We developed a technique to determine the total twist angle and handedness of the twist by using optical transmission spectroscopy. We present the theoretical background and experimental technique and test it against some other results and results from data published elsewhere. Furthermore, we investigate the use of three naturally occurring terpenoid materials as chiral dopants for liquid crystals and determine the helical handedness using the spectroscopy method.
... Suregada zanzibariensis also called mdimu msitu in Tanzania, is a timeless shrub or a small tree with horizontal branches that grows up to 0.5-10 m tall, and occurs usually on sandy soils in woodland, riverine forest, coastal forest and in salt marshes, from sea-level up to 1200 m altitude 5 . The root and stem bark extracts of Suregada zanzibariensis are used in Tanzania to treat ancylostamiasis and a tea from the roots is drunk to treat gonorrhoea, stomach ache, chest pain, hernia, pneumonia and snake bites and the leaves are used to treat skin infections 12 . On other hand it has been reported that traditional healers are using the roots decoction of Suregada zanzibariensis to treat and manage diabetes mellitus 5 . ...
Background: Traditional healers utilize the roots of Suregada zanzibariensis for managing diabetes mellitus. Therefore, evaluation of toxic properties of this plant is important. Objective: To evaluate acute oral toxicity of S. zanzibariensis root extract on Wistar rats and to screen phytochemical compounds of the EAESZ. Methods: GCMS analysis of the plant extracts were performed by using GCMS-2010 Shimadzu and mass spectra of the compounds found in the extract was matched with the data in the library of National Institute of Standards and Technology (NIST). Acute oral toxicity testing was carried by administering a single Distilled water extract (DWESZ) and EAESZ to four different groups of rats at dosage of 300mg/kg and 2000mg/kg in each extract to the separately group of rats Results: The GC-MS analysis of S. zanzibariensis roots extract revealed the presence of 10 major compounds. A higher single dose (2000mg/Kg) of EAESZ and DWESZ extract did not produce any sign of toxicity throughout 14 days of study, in terms of changes in behaviour or mortality in tested rats. No significant (p > 0.05) hematological, liver histological, biochemical changes were noticed between rats treated and control rats Conclusion: The results obtained suggest that the plant extract can be classified as non-toxic. Keywords: Phytochemical profiling; acute oral toxicity; Suregada zanzibariensis (Baill) root extract.
... Acetone/petroleum jelly mixture (1:1) was negative control while 20% DEET (N, N-diethyl-m-toluamide) was the positive control. Volunteers who had avoided use of fragrance, any mosquito repellent, perfumed soap or tobacco for 12 hours prior and during the experiment (WHO, 2009;Innocent et al., 2010) were used for the experiments. The forearm, from the elbow to the wrist (~696.6 cm 2 ) was rinsed with water then dried in air. ...
Diseases transmitted by mosquitoes cause human morbidity and mortality and also lead to economic loss and social disruption in the poorest countries of the world. Repellents reduce mosquito host interaction, bites and associated distress. Many repellents in use today are expensive, of synthetic origin, have been associated with adverse effects and toxicities. Extensive use of chemicals has resulted in environmental toxicities, non-acceptance by users and resistance by the insects. Plants and plant products have repellent activities, do not persist in the environment and do not have major effects on non-target organisms and plants. They can substitute synthetic insecticides or complement the use of the same. The aim of this study was to develop a plant-based mosquito repellent formulation that is safe and efficacious to use. The plants from Msambweni subcounty, Kwale county, Kenya were selected for the study on the basis of ethnomedicinal and literature review of plants of on their use against mosquitoes. The plants' extracts were made into two formulations of 10% (formulation A) and 20% (formulation B). Acute dermal irritation and corrosion was assessed using New Zealand white rabbits according to OECD test guideline number 404. Repellency tests were performed according to the protocol of world health organization (WHO) using Aedes aegypti mosquitoes on human volunteers. The WHO bioassay method was used to determine knockdown effects of the formulations against mosquitoes. The two formulated products did not exhibit dermal irritation/corrosion on the rabbit or human skin. They exhibited a repellence effect greater than or similar to DEET. They can offer suitable substitutes to most synthetic repellents.
... Verbenone has anti-aggregation property and interrupts the attraction of bark beetles to their aggregation pheromones. [71,72] fenchylacetate 0.78 ...
... Giriama and Duruma people use a root decoction to treat body swelling. Digo people use the root decoction for body pains, for pains during menstruation, and to avoid premature birth [28,29]. The wood of S. zanzibariensis is hard and used for tool handles, building poles, spoons, withies, and firewood. ...
... The roots are boiled, and the juice is drank twice a day as a purgative [14]. [21,26,27,29] Roots and stem bark Ankylostomiasis [25,29] Roots Gonorrhoea, chest pain, stomach ache, hernia, chicken pox, schistosomiasis, body swelling, pneumonia and purgative [14,25] Wood Building poles, tool handles, withies, fuel and spoons [14] ...
... The roots are boiled, and the juice is drank twice a day as a purgative [14]. [21,26,27,29] Roots and stem bark Ankylostomiasis [25,29] Roots Gonorrhoea, chest pain, stomach ache, hernia, chicken pox, schistosomiasis, body swelling, pneumonia and purgative [14,25] Wood Building poles, tool handles, withies, fuel and spoons [14] ...
Plants of the Suregada Roxb. ex Rottler (formerly Gelonium Roxb. ex Willd) are utilized to treat various ailments, namely, hepatic, gum diseases, pyrexia, eczema, and venereal diseases. This review links the reported compounds to ethnomedicinal uses through pharmacological activities. The compounds possess anticancer, anti-allergic, antibacterial, anti-inflammatory, antioxidant, and anti-HIV properties. From the previous reports, 32 known species of the Suregada genus have been investigated morphologically, and nine were investigated for their phytochemistry and pharmacol-ogy. Phytochemistry, ethnomedicinal, and pharmacological uses of the other 23 Suregada species are not known and/or not reported. In this review, abietane diterpenoids are the main compounds expressed by the Suregada, accounting for 71 of the 114 reported compounds. Ten triterpenoids and sterols, one aliphatic, two lignans, five flavonoids, and twenty-one nitrogen-containing compounds have been reported from the genus.
... Various plant mixtures are also directly applied on the skin for protection against hematophagous insects. The compounds present in the plants are used to repel or give toxicity to the bloodsucking insects (Seyoum et al., 2002;Moore et al., 2006;Innocent et al., 2010). Many known plants from various families such as Myrtaceae, Lauraceae, Rutaceae, Lamiaceae, Asteraceae, Apiaceae, Fabaceae, Menispermaceae, Acanthaceae, Amaryllidaceae, Zingiberaceae and Piperaceae exhibit mosquito larvicidal activity (Seyoum et al., 2002). ...
Mosquitoes (Diptera: Culicidae) act as vectors of a wide variety of human and veterinary pathogens and parasites. In controlling mosquito population, the use of compounds from plants is considered advantageous; they are target-specific and biodegradable. These secondary metabolites are referred to as green pesticides as they are reported to be efficient and safe for other vertebrates. The activity of the phytocompounds against mosquito larvae varies significantly depending on several factors such as the species, plant parts used, age (young or old), mature or senescent and solvent used during extraction. Different secondary metabolites from plants have different potentials which affect insect behavior, repel the pest, disrupt feeding activity, affect pest physiology, inhibit respiration and growth, reduce fecundity and disrupt cuticle formation. This review provides a critical analysis of plant chemicals with mosquito larvicidal efficacy and their mode of action, which have been reported for the past 10 years. Several online databases including PubMed, Scifinder, Google Scholar and Web of Science were used in searching for information on mosquito larvicidal metabolites from plants. A total of 180 compounds from 97 plant species having larvicidal activity was recorded. Among these, only 26 compounds presented larvicidal activity <1parts per million (ppm) against larvae of the mosquito species of health importance. Compounds such as methyl palmitate, proanthocyanidins, 22-monacetonide, and 20-hydroxyecdysone recorded 100% larvicidal activity against An. gambiae and Ae. aegypti. A total of 91 compounds showed larvicidal activity against different mosquito species at 1–25 ppm concentrations. Generally, the insecticides with toxicity were reported to interfere with nerve functions, physiology, development and as well hamper the insect's day-to-day activities. Currently, the research on the mode of action of biomolecules from plants is scarce. In future, the researchers should study the mode of action of these larvicides.
... Suregada zanzibariensis, a plant endemic to East Africa including Kenya has recently attracted the attention of different research group as a source of ent-abietane lactones with a large spectra of activities. Previous biological studies on the methanol extract of the leaves demonstrated good antiplasmodial activity (Kigondu et al. 2009), and its essential oil displayed insect repellence activity (Innocent et al. 2010). In another investigation, from the stem bark of S. zanzibariensis, Mangisa et al. nicely demonstrated the cytotoxicity and anticancer properties of mangiolide and jolkinolide B against a panel of cancer cell lines (Mangisa et al. 2019). ...
The root extract of Suregada zanzibariensis Baill. afforded six previously described ent-abietane diterpenoids, namely 7-oxo-ent-abieta-5(6),8(14),13(15)-trien-16,12-olide (1), mangiolide (2), 8,14β:11,12α-diepoxy-13(15)-abietane-16,12-olide (3), 7β,11β,12β-trihydroxy-ent–abieta-8(14),13(15)-diene-16,12-olide (4), 8α,14-dihydro-7-oxo-jolkinolide E (5), jolkinolide A (6), together with 3β-sitosterol (7), scopoletin (8) and vanillin (9). Their structures were deduced through 1D and 2D NMR spectroscopic techniques, and HRESIMS, as well as by comparison of the NMR data with those reported in the literature. The crude extract and compounds 1–9 were evaluated for their antiplasmodial, antifungal and antibacterial activities. Mangiolide (2) showed strong in vitro antiplasmodial activity against chloroquine sensitive (D6) and resistant (W2) strains of Plasmodium falciparum with IC50 values of 0.79 and 0.87 µg/mL, respectively, while 3 (IC50 1.24 and 1.17 µg/mL) was less active than 2. Compound 2 also displayed antimicrobial activity against Cryptococcus neoformans, methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant Enterococcus faecium (VRE) with IC50 values of 1.20, 3.90 and 7.20 µg/mL, respectively.
... Repellence activities against Anopheles gambiae s.s. have been demonstrated by essential oil extracts of Suregada zanzibariensis leaves [13] . Tagetes lucida, Lippia alba, Lippia origanoides, Eucalyptus citriodora, Cymbopogon citratus, Cymbopogon flexuosus, Citrus sinensis, Swinglea glutinosa and Cananga odorata essential oils and of a mixture of L. alba and L. origanoides essential oils have shown repellence to Aedes (Stegomyia) aegypti Rockefeller larvae [14] . ...
Abstract
Mosquitoes continue to transmit malaria despite the use of several methods of control such as treated bed nets, aerosols and repellent creams. Mosquito biting cause stress and medical problems to school going children. An experimental ecological study was undertaken to evaluate the effectiveness of two months old potted Artemisia annua plants for mosquito repellence in boarding schools’ dormitories of Mwea Rice Irrigation Scheme, Kenya. Two months old potted live A.annua plants were hung next to doors and windows of dormitories and mosquito collection for four months as per WHO protocol was done. The study found significant differences in the mean mosquito catches in treatment dormitories in both girls
and boys boarding schools p-values of 0.005, 0.001, 0.001, and 0.001 for the 2nd, 3rd, 4th and 5th months respectively. The study concluded that live A.annua reduced mosquito density in dormitories of boarding schools. Further there was reduction of mosquito density in neighbouring dormitories, as far as 50metres where A. annua was not introduced. The study recommends that A.annua would be very important for implementing vector control strategies to prevent man-vector contact for the prevention of vector borne diseases.
The study recommends use of A.annua as vector control strategy to prevent man-vector contact for the prevention of vector borne diseases.
Keywords: Artemisia annua, Anophelines, repellency, boarding schools
... Ancient people frequently use PEOs to control mosquitoes or other insects (da Silva et al., 2017a,b;Dell'Agli et al., 2012;Maia and Moore, 2011;Renkema et al., 2016;Souza et al., 2019). Among the PEOs, the essential oil from Citronella has been used as a standard mosquito repellent since the World War II (Innocent et al., 2010;Veeder, 1980;Wigglesworth, 1948). ...
The use of laser biostimulation technology in agriculture has thus far been limited to assessment of the effect of stimulation of seeds or seedlings on crop yield, mainly due to the technical limitations of the apparatus. Advances in mechatronics will enable broader application of laser biotechnology, for stimulation of plants in field conditions in order to minimize biotic and abiotic stress throughout their growth and development. This will increase productivity and improve crop quality, while reducing the use of pesticides, minimizing mineral fertilization, and increasing nutrient utilization by crop plants. Laser biotechnology can be used not only in agriculture, but also in energy production and environmental protection. More effective reclamation of degraded areas through biostimulation of plants can significantly increase the production of biomass as an energy raw material and contribute to the development of renewable bioenergy production (with no negative effect on food production) and the entire bioeconomy. Wider use of laser biotechnology can also contribute to more effective environmental protection and better exploitation of water resources by substantially increasing the efficiency of hydrobotanical wastewater treatment plants.
... The plant generally has smooth, bark grey, green stems and obovate leaf blade to elliptic obovate (Palgrave 2002). The root and stem bark extracts are used in Tanzania to treat ankylostamiasis and a tea from the roots is drunk to treat gonorrhoea, stomach ache, chest pain, hernia, pneumonia and snake bites and the leaves are used to treat skin infections, Innocent et al. 2009 further reported that the essential oil of the leaves of S. zanzibariensis were found to be mosquito repellent. ...
Clerodendrum glabrum is an indigenous medicinal plant that is used to treat cough, cold, sore throat and chest complaints. The stem bark of Clerodendrum glabrum afforded four tritepenoids namely, 3β-olean-12-en-3-yl palmitate (β-amyrin palmitate), (1), 3β‑hydroxy‑5-glutinene (glutinol), (2), 3β-lup-20(29)-en-3-palmitate (Lupeol-3-palmitate), (3), 3β-lup-20(29)-en-3-ol (lupeol) (4) and one common phytosterol (stigmasterol) (5). The structures were established on the basis of their spectroscopic analysis. The compounds were screened for cytotoxicity against the HCC70 triple negative breast cancer (TNBC), MCF-7 hormone receptor positive breast cancer and MCF-12A non-cancerous mammary epithelial cell lines. Interestingly, none of the compounds were toxic towards hormone receptor positive breast cancer cells, while displaying varying toxicity against the TNBC and non-cancerous breast epithelial cells. In particular, lupeol-3-palmitate (47.6 ± 1.50 μM) and glutinol (26.9 ± 1.30 μM) displayed the greatest inhibitory activity against the HCC70 cell line, with the former being selectively toxic to HCC70 and not MCF-12A non-cancerous cells.
