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Chapter 4 - Clove (Syzygium aromaticum) polysaccharides
(Elsevier, 2022) Cheikhyoussef, Ahmad
Clove (Syzygium aromaticum (L.) Merr. & Perry) is an essential herb with well-documented health beneﬁts. Carbohydrates were detected in the ethanolic bud extract of S. aromaticum. Two antithrombotic polysaccharides were isolated from the ﬂower buds of clove by anion-exchange chromatography, hydrophobic interaction column chromatography, and size exclusion chromatography with molecular weight ranging from ca. 34,000 to ca. 103,000 Da. Clove polysaccharides have the backbone of type I rhamnogalacturonan, and the side chain of arabinan with the sulfate is being positioned at 6 of 3-linked galactosyl residues. Although polysaccharides from cloves have an antithrombotic ability, their activities in vitro are lower than that of heparin. Sulfated polysaccharides from cloves show a slightly lower salt concentration due to their relatively low sulfate/sugar ratio, which gives distinctive structural characteristics compared to other polysaccharides such as algae polysaccharides. The anticoagulation action with no toxicity in vivo of low molecular weight sulfated polysaccharide may represent a valuable and safe antithrombotic agent. This chapter gives an overview of polysaccharides from S. aromaticum, their characteristics, and their potential applications.
Clove (Syzygium aromaticum) phenolics: Extraction, compositions, and biological activities
(Elsevier, 2022) Cheikhyoussef, Ahmad
Clove (Syzygium aromaticum L.) is a dried ﬂower bud belonging to the Myrtaceae family indigenous to Indonesia. Recently, it has been farmed in diﬀerent places worldwide with potential food and nutraceutical applications. Clove volatile compounds contribute to the smell and unique aroma; meanwhile, nonvolatile compounds in the clove are mainly responsible for the taste. Clove is well known for its high level of antioxidants because of the ﬂavonoids, hydroxy benzenes, phenylpropanoids, and other reducing substances. Clove phenolics comprise between 8% and 12% (w/w) gallic acid equivalents and are mainly composed of hydrolyzable tannins, phenolic acids, ﬂavonoids, and eugenol, major bioactive molecules in this valuable herb. Gallic acid is the highest among the phenolic acids in clove and other gallic acid derivatives such as hydrolyzable tannins, which are also present in higher concentrations. Other phenolic acids found in the clove are ellagic, ferulic, caﬀeic, and salicylic acids. In addition, ﬂavonoids such as quercetin and kaempferol were reported. This chapter will focus on clove phenolics’ structure, composition, and biological activities.
Dominant lactic acid bacteria and their antimicrobial profile from three fermented milk products from northern Namibia
(2014) Heita, Lusia; Cheikhyoussef, Ahmad
The present study focused on the isolation, identification and antimicrobial profile of the dominant lactic acid bacteria from three traditional fermented milk products namely: Omashikwa, Mabisi and Mashini Ghamushikwa from the north-central and north-eastern parts of Namibia. The microbiological and antimicrobial activities of these products fluctuate from one region to another depending on the local indigenous microflora. Omashikwa and Mashini Ghamushikwa fermentation processes involves the addition of Boscia albitrunca root (Omunkuzi) and butter churning. The root contributes to the flavor of the product, increasing the milk fermentation rate and churning. Mabisi is produced by letting the milk to ferment naturally until the water is separated from the whey. The water is then decanted, and the whey is shaken until it is smooth without removal of fat. A total of 180 isolates of Lactic acid bacteria (LAB) were obtained and identified based on their phenotypical characterization. Cell free supernatants (CFS) of the 180 LAB isolates were evaluated for antimicrobial activities against selected food borne pathogens; Escherichia coli ATCC 25,922, Staphylococcus aureus ATCC 25,923, Bacillus cereus ATTC 10,876, Candida famata and Geotrichum klebahnii using the well diffusion assay. Twenty LAB isolates having the highest inhibitory effects were selected for biochemical identification using API 50 kit and these were identified as being; Lactobacillus plantarum (53%), Lactobacillus rhamnosus (29%), Pediococcus pentosaceus (6%), Lactobacillus paracasei ssp. paracasei (6%) and Lactococcus lactic ssp. lactis (6%). Pediococcus pentosaceus showed the highest inhibitory effect on all the indicator strains. This study provides an insight into LAB diversity of unstudied Namibian fermented milk products and reports a potential production of antimicrobial compounds which is significant in the standardization of protective starter cultures which can be used to control fermentation process and shelf life extension of dairy products in Namibia.
Ethnobotanical knowledge on indigenous fruits in Ohangwena and Oshikoto regions in Northern Namibia
(2013) Cheikhyoussef, Ahmad; Embashu, Werner
Background: Indigenous communities in Namibia possess a rich indigenous knowledge expressed within many practices of these communities. Indigenous wild edible fruits are available along the Namibian 13 regions of which it forms a rich source of vitamins, fibres, minerals and a heterogeneous collection of bioactive compounds referred to as phytochemicals for indigenous people’s diet. The aim of this study was to record the different IKS practices on the indigenous fruit trees in Ohangwena and Oshikoto regions of Namibia. Methods: An ethnobotanical survey was undertaken to collect information from local communities from 23-29 October 2011. Data was collected through the use of questionnaires and personal interviews during field trips in the Ohangwena and Oshikoto regions. A total of 65 respondents were interviewed; 54% women, 38% men and 8% both in group interviews. Results: The majority of the people interviewed were in their thirty’s, with the youngest being 18 years old and the oldest being 98 years old. Forty three plant specimens were collected from the two regions; these specimens belong to 20 genera and 25 species. Regarding to the indigenous knowledge; 87% of the respondents indicated that their knowledge on indigenous fruits was learnt mainly through their parent. Indigenous people’s perception on declining indigenous fruits revealed that 56.3% of the respondents reported that indigenous fruits were declining. Only a 42.2% indicated that the indigenous fruits populations are increasing. Regarding to the management practices to improve the production of these indigenous fruit trees; 38.6% reported that there are some efforts on management practices; on the other hand 61.4% reported there are no management practices on the indigenous fruit trees in their areas. Four species were found to be the most frequently used and mentioned fruits which need to be given high preference in terms of conservation are: Berchemia discolor, Hyphaene petersiana, Sclerocarya birrea and Diospyros mespiliformis. The following diseases and ailments have been reported to be treated by the indigenous fruit trees which include: toothache, diarrhoea, cough, tonsillitis, burns, skin allergy, stomach ache, snake bit, constipation, etc. 28% of the respondents mentioned an ethno veterinary use(s) of these fruits, e.g. the use of the Ziziphus mucronata roots to treat diarrhoea in cattle, the bark of eembe (Berchemia discolor) to treat calf weakness. Conclusions: The local communities in Oshikoto and Ohangwena regions have relatively good knowledge and practices regarding the indigenous fruit. This study enhances our understanding on the indigenous fruit in Namibia and their uses by local communities.
Ethnobotanical study of indigenous knowledge on medicinal plant use by traditional healers in Oshikoto region, Namibia
(2011) Cheikhyoussef, Ahmad; Shapi, Martin K.; Matengu, Keneth K.; MuAshekele, Hina
The objective of this study was to establish a regional profile of the indigenous knowledge system (IKS) for medicinal plant use and cultural practices associated with the healing process of these plants by traditional healers in the Oshikoto region, Namibia. An ethnobotanical survey was undertaken to collect information from traditional healers during September and October 2008. Data was collected through the use of questionnaires and personal interviews during field trips in the ten constituencies of the Oshikoto region. A total of 47 respondents were interviewed with most of them aged 66 and above. The traditional healers in Oshikoto region use 61 medicinal plant species that belong to 25 families for the treatment of various diseases and disorders with the highest number of species being used for mental diseases followed by skin infection and external injuries. Trees (28 species) were found to be the most used plants followed by herbs (15 species), shrubs (10 species) and climbers (4 species). The average of the informant consensus factor (FIC) value for all ailment categories was 0.75. High FIC values were obtained for Pergularia daemia, and Tragia okanyua, which were reported to treat weakness and dizziness problems, snake bite, swelling and cardiovascular problems indicating that these species traditionally used to treat these ailments are worth examining for bioactive compounds. The traditional healers in Oshikoto possess rich ethno-pharmacological knowledge. This study allows for identifying many high value medicinal plant species, indicating high potential for economic development through sustainable collection of these medicinal plants.
General practices on indigenous knowledge system technology in selected regions of Namibia
(2012) Shapi, Martin K.; MuAshekele, Hina; Cheikhyoussef, Ahmad
Research into Indigenous Knowledge System Technology (IKST) has been receiving increasing attention from research institutions and Government Ministries in Namibia during the last five years. Indigenous communities in Namibia possess a rich traditional knowledge expressed in many practices in their communities. This study aims to present and identify general indigenous practices that have potentials for development in four regions in Namibia. These regions were Omaheke, Oshikoto, Omusati and the Kavango. These indigenous technologies covered medical, pharmaceutical, indigenous food, tanning, construction and infrastructure technologies and household equipment of the local. This research article also presents Namibia’s best Indigenous Knowledge System Technology practices as compared to United Nations Educational, Scientific and Cultural Organization (UNESCO) and the Netherlands organisation for international cooperation in higher education (Nuffic) protocols. The comparison shows the potentials of these technologies despite their simplicity and poorly developed structures. The local communities need be educated on the importance of these indigenous technologies. The youth should also be encouraged to learn these knowledge systems to preserve them from being lost with the older generation.
Indigenous knowledge system best practices from Namibia: The case of Oshikundu processing methods
(2012) MuAshekele, Hina; Embashu, Werner; Cheikhyoussef, Ahmad
In recent years there has been increasing recognition by researchers, governments and development agencies That Indigenous Knowledge System (IKS) is one of the sources of knowledge which can be easily understood, accessed and useable to, particularly, people and communities in developing countries. Namibia, as a developing country is no exception in this case. The aim of this study is to present the production processes of oshikundu, a traditional fermented beverage in northern Namibia and to identify the practices that have potential for commercialization. The general IKS best practice protocol of the United Nations Educational Scientific and Cultural Organization and the Netherlands organization for international cooperation (known as Nuffic) will be used to evaluate the production processes that would lend oshikundu for commercialization. The research was carried out in the four “O” northern central regions of Namibia, where the majority of the inhabitants live in rural areas and where they produce and drink oshikundu in the traditional way. The results will be used to draw conclusions, implications and possible applications of how the oshikundu can be processed better and possibly made accessible in modern shops without changing too much its traditional taste.
Medicinal properties of Ximenia: Lessons from the traditional healers in Oshikoto region, Namibia
(2010) Cheikhyoussef, Ahmad; Shapi, Martin K.; Matengu, Keneth K.; MuAshekele, Hina
Ximenia is an important indigenous plant in many countries and used often in herbal preparations by traditional healers. The plant is claimed to possess medicinal properties and is used in the treatment of different ailments and diseases. The aim of this study is to report some of the medicinal properties of Ximenia used by traditional healers in Oshikoto region. An ethnobotanical survey was undertaken to collect information from traditional healers on their use of medicinal plants in the traditional healing system. It was found that Ximenia is the most frequently used medicinal plant. A total of 47 respondents were interviewed; most of them were at the age of 66 years and above. The traditional healers in Oshikoto region use X. americana and X. caffra to treat various diseases and disorders such as Gonorrhea, Culture Bound Syndrome (CBS), Impotency and Scoliosis. Both forms of the plant status (fresh and dry) were used during the medicinal preparations. Roots are the most used parts in the treatment. The average of the fidelity level (FL) of the both species for all ailments was 33.33% with the highest FL for X. caffra to treat CBS of 66.66%. This study is confirming the potential value of using Ximenia species in traditional medicinal remedies in Oshikoto region in Namibia.
The Namibian bioeconomy: Transformation to a sustainable society?
(Springer, 2020) Hauser, Anne Heeren; Cheikhyoussef, Ahmad; Chimwamurombe, Percy M.
Worldwide, bioeconomy is promoted as an ‘engine for sustainable development’. However, increasingly, the notion that ‘the bioeconomy’ will facilitate sustainable development per se is challenged. Based on the assumption that when leaving the relations between ‘nature’ and ‘society’ unquestioned, inherent inequalities are rather reproduced than overcome, we draw upon a social-ecological framework to analyse the societal relations to nature in the Namibian bioeconomy. In Namibia, with independence, an array of diferent beneft-sharing mechanisms have been developed to implement local participatory governance structure, which will be further streamlined under the newly introduced access and beneft-sharing law. Results show that despite eforts to facilitate a diversity-based bioeconomy, separating structures and trade-ofs are persistent. Images of ‘nature’, like the ‘eternal Namibian landscape’, that draw upon colonial notions are frequently used to market indigenous natural products. Institutions to ‘nature’ that guarantee fair and equitable terms of trade are often only short-term and/or small-scale, e.g. as shown at the case of Devil’s claw, Hoodia and Namibian Myrrh. Even when perspectives cannot be assigned in a stereotypical way between user and provider, and instead, all actors refer to biodiversity and traditional knowledge as ‘welfare of the people’, ‘cultural heritage’, ‘input for R&D’, ‘community beneft’, and ‘marketing tool’, a rational-instrumental reasoning tends to be favoured of a normative-ethical one. A more diversifed awareness towards the dialectics entailed in the conception, making, and management of ‘nature’ potentially inhibiting an inclusive sustainable development is relevant at any theory–practice interface, including development project-management and environmental policy-making.
Phytochemical properties of a Namibian indigenous plant; Eembe (Berchemia discolor)
(2010) Cheikhyoussef, Ahmad; Naomab, Erold; Potgieter, Sannette; Kahaka, Gladys K.; Raidron, Celestine Vida; MuAshekele, Hina
The aim of this study was to investigate the phytochemical properties of Eembe (Berchemia discolor); one of the underutilized indigenous plant in Namibia. This species is distributed in the northern part of Namibia and has many general uses. The fruit is high in sugar and contains vitamin C. It is eaten fresh or dried and stored for use in the dry season. Dried fruit have a datelike flavour. Fresh fruit is fermented to make beer and wine. The bark is used medicinally and for basket dye. The wood is used for furniture, hut construction and other items. There have been no previous investigations on the bioactive metabolites of B. discolor in Namibia. B. discolor extracts (fruits, leaves and barks) were prepared by different organic solvents. Qualitative phytochemical analysis of the extracts was performed to investigate the presence of: Tannins, Alkaloids, Flavonoids, Saponins, Total Phenols, Steroids, Phlobatanins, Terpenoids, Cardiac Glycoside and Anthraquinone. The significance of Eembe (B. discolor) in traditional medicine and the importance of the distribution of its chemical constituents will contribute in elucidating the importance of this plant in ethnomedicine in Namibia.
Study on fermented milk (Omashikwa) in northern Namibia (Ohangwena, Oshana, Oshikoto and Omusati) regions
(2012) Heita, Lusia; Cheikhyoussef, Ahmad
EXECUTIVE SUMMARY: Traditional fermented milk products are widely consumed in the entire world. These products are an important supplement to the local diet and provide vital elements for growth, good health and an appreciate flavor. In Namibia there are many types of fermented milk which are commonly eaten by local people. This study focused on Omashikwa which is the traditional fermented milk of Oshiwambo speaking people and mostly found in four regions Ohangwena, Oshikoto, Oshana and Oshikoto. The purpose of this study was to collect fermented milk samples and to document the processing and the house hold preservation methods of Omashikwa. The samples collected will be used to examine the antimicrobial properties of Lactic Acid Bacteria or LAB isolates with potential probiotic use in order to control and eliminate the spread of harmful bacteria in food products. A total of 13 samples were collected and 13 questionnaires were filled in. The first region visited was Ohangwena region in which one village was surveyed, then Omusati region; three villages, Oshana four villages lastly Oshikoto only two villages. The pH of the samples was done in the field using a pH meter. The pH average ranged between 3.44 - 3.83. There was no significant difference in the house hold processing method of the Omashikwa among the Oshiwambo speaking people. Regarding the indigenous knowledge, all respondents indicated that the milk have social value as it act as a source of income to many. The milk has a very short shelf life of only seven to twelve days.
Study on indigenous fruits and ethnobotanical uses in Ohangwena and Oshikoto regions
(2012) Cheikhyoussef, Ahmad; Embashu, Werner; Heita, Lusia; Potgieter, Sannette
SUMMARY: Research into Indigenous Knowledge System Technology (IKST) has been receiving increasing attention from various research institutions and Government Ministries in Namibia during the last five years. Indigenous communities in Namibia possess a rich traditional knowledge expressed in many practices in their communities. Indigenous wild edible fruits are available within the Namibian 13 regions which provide a rich source of vitamins and fibres for indigenous people’s diet. The aims of this study were to record the different IKST practices on the indigenous fruit trees in Ohangwena and Oshikoto regions. Three constituencies in Ohangwena region were surveyed; these including Okongo, Eanhana and Ondobe Constituencies. In Oshikoto region; only one constituency which is Onayena was included in the survey. A total of 65 respondents were interviewed; 54% women, 38% men and 8% both in group interviews. The majority of the people interviewed were in their thirty’s, with the youngest being 18 years old and the oldest being 98 years old. Thirty eight plant specimens were collected of which 24 are from Ohangwena and 15 from Oshikoto region, these specimens belong to 18 genuses and 23 species. Regarding to the indigenous knowledge; most of the respondents indicated that their knowledge on indigenous fruits was learnt mainly through their parents. Almost all of the respondents reported that the indigenous fruits and their products have social values such as it is presented to guests at special ceremonies, weddings, etc. In addition to their social values; health values have been reported also especially with regard to has flu. Some people depend on these fruits and their by-products to get income, for example Distilled liquor from Eembe (Berchemia discolor), Palm fruits (common practice in Oshikoto region). Most of the peoples reported that the traditional beer and wines are the main products made from these fruits.
Study on indigenous medicinal knowledge in Caprivi region
(2011) Du Preez, Iwanette C.; Nepolo, Emmanuel; Siyengwa, Riina; Shapi, Martin K.; Cheikhyoussef, Ahmad; Mumbengegwi, Davis R.
SUMMARY: Indigenous knowledge is defined as the uniqe knowledge in a given culture, which is passed on orally from generation to generation (Mapaure & Hatuikulipi, 2007; Dan et al., 2010). This indigenous knowldege is regarded as valuable and considered as the local people’s capital (Mapaure and Hatuikulipi, 2008; Cheikhyoussef et al, 2011), and if not preserved, it may be lost forever to society. The study on Indigenous Medicinal Knowledge in Caprivi region was done in collaboration with the Directorate of Research Science and Technology (DRST) of the Ministry of Education, and was done as a continuing research work for the national survey on Traditional Healing in Namibia. The traditional medical systems are generally based on the uses of natural and local products which are commonly related to the people’s perspective on the world and life (Toledo et al. 2009). Traditional African medicine is 'the sum total of practices, measures, ingredients and procedures of all kinds whether material or not, which from time immemorial has enabled the African to guard against diseases, to alleviate his/her suffering and to cure him/herself' (Busia, 2005). The traditional healing practices in Namibia have been studied by a number of researchers (Shapi et al, 2009; Dan et al, 2010). The aim of this national survey will be to create a database based on the indigenous knowledge of medicinal plants used by traditonal healers and/or knowledge holders to treat a variety of ailments and diseases, as well as for cultural beliefs and practices. As such, the overall aim of this fieldtrip was to interview traditonal healers in the Caprivi region and retrieve as much information as possible with regarding to the uses of medicinal plants, and to collect voucher specimens to be deposited with the National Botanical Research Institute (NBRI), Windhoek, Namibia.
Survey on indigenous knowledge and household processing methods of Oshikundu: A cereal-based fermented beverage from Oshana, Oshikoto, Ohangwena and Omusati regions in Namibia
(2012) Embashu, Werner; Cheikhyoussef, Ahmad; Kahaka, Gladys K.
SUMMARY: The aim of this study is to survey the indigenous knowledge and Household processing methods of Oshikundu; a cereal-based fermented beverage from Oshana, Oshikoto, Ohangwena and Omusati Regions in Namibia. A field trip to the above mentioned regions was carried out from 16-21 April, 2012. A total of 22 Oshikundu samples were collected and 12 questioner on the traditional household processing method. Oshikundu was found to be acidic, with an average pH 3.56. Oshikundu has social values and serves as an important daily beverage in many households. Variations were not observed in household processing methods among the four regions and women over the age of 60 years old have shown interest and knowledge when it comes to Oshikundu. Interestingly, they were quick to point out that the Oshikundu brewed in the 21st century is not the genuine Oshikundu as they grew up drinking it. Furthermore, they attributed this to modernization, loss of interest in traditional knowledge and its practices, and lack of documentations. In addition, young people claimed they put sugar in Oshikundu to enhance the taste. It was interesting to learn that some people feared that researchers have (might) exploit their resources and knowledge, the art of processing, brewing Oshikundu. This can be linked to secrecy of Indigenous knowledge, where secrecy may be used to stop the unauthorized flow of information from the traditional knowledge holders to outsiders. Findings for similar research that involves communities’ participants should look at communication strategy to disseminate information back to the community
Traditional knowledge of wild edible fruits in southern Africa: A comparative use patterns in Namibia and Zimbabwe
(2017) Maroyi, A.; Cheikhyoussef, Ahmad
A large proportion of resource poor rural households in southern African communal areas are dependent on wild edible fruits to meet part of their daily nutritional needs. For many people and ethnic groups, the use of wild edible fruits is a source of cultural identity, reflecting a deep and important body of knowledge about the environment, survival, harvesting, preservation and other forms of management. This study was aimed at at documenting the role of wild edible fruits in the livelihoods of people in Namibia and Zimbabwe.
The use of some indigenous plants for medicinal and other purposes by local communities in Namibia with emphasis on Oshikoto region: A review
(2011) Cheikhyoussef, Ahmad; Mapaure, Isaac; Shapi, Martin K.
Local communities in Namibia possess an in-depth knowledge of the use of medicinal plants and their environment. Medicinal plants contribute significantly to the intellectual property rights of poor local households in theses local communities. This review gives an overview of the use of indigenous knowledge held by traditional healers, the uses of indigenous plants for medicinal and other purposes, medicinal preparation methods and treated diseases in different parts of Namibia, in particular the Oshikoto region. Factors threatening the existence of the medicinal plants are discussed and the gaps in the indigenous knowledge on the uses of the medicinal plants are also presented. This review strongly recommends the importance of proper and comprehensive documentation of the traditional healing methods in Namibia, which will have a high potential for sustainable development for the medicinal plants in Namibia.
Value addition and processed products of three indigenous fruits in Namibia
(2013) Cheikhyoussef, Ahmad; Bille, P.G.; Shikongo-Nambambi, Martha N.;
The objectives of this study were to add value to three popular indigenous fruits found in Namibia namely, Marula (Sclerocarya birrea), Monkey orange (Strychnos cocculoides) and Eembe (Berchemia discolour) into processed food products and to train rural communities on value addition for job creation, income generation and food security. Indigenous fruits are receiving increasing interests from researchers and scholars because of their nutrition and abundance in most African countries. The fruits are important sources of food for rural communities especially at times of food shortage, hunger and other disasters. In addition, they provide enormous health benefits such as antioxidants, vitamins and minerals. They are also known to create jobs and generate income for rural communities. Because of their role in combating food insecurity, nutrition and the problems of seasonality, studies on their value addition were carried out in Namibia. Different types of food products were made from the fruits namely; juice, jam, jelly and muffins (cakes). A pilot study was carried out to determine the levels and preference range of ingredients in the mix to formulate recipes of the products prior to processing and training the community members. The results were subjected to paired preference tests and the best ratio was then used. According to consumer preference test, marula juice was on the lower value (2.3) due to its low pH (3.26). As for jam and jelly; quality, taste and colour were acceptable and preferred. The three products made from monkey orange were all preferred but those from eembe were downgraded (2.31-3.20) due to dark colour and lack of flavour. The microbiological quality of the produced products confirmed their safety characteristics. The products made in this study were shown to be viable, of good quality and good sources of income for rural communities. The fruit flavour from marula and monkey orange can be utilized in the dairy and other soft drink industries for making yoghurts, sour milk, ice cream, juices and jams.

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