Spider Plant Research Articles

Free amino acids in African indigenous vegetables: Analysis with improved hydrophilic interaction ultra-high performance liquid chromatography tandem mass spectrometry and interactive machine learning

A hydrophilic interaction (HILIC) ultra-high performance liquid chromatography (UHPLC) with triple quadrupole tandem mass spectrometry (MS/MS) method was developed and validated for the quantification of 21 free amino acids (AAs). Compared to published reports, our method renders collectively improved sensitivity with lower limit of quantification (LLOQ) at 0.5~42.19 ng/mL with 0.3 μL injection volume (or equivalently 0.15~12.6 pg injected on column), robust linear range from LLOQ up to 3521~5720 ng/mL (or 1056 ~ 1716 pg on column) and a high throughput with total time of 6 min per sample, as well as easier experimental setup, less maintenance and higher adaptation flexibility. Ammonium formate in the mobile phase, though commonly used in HILIC, was found unnecessary in our experimental setup, and its removal from mobile phase was key for significant improvement in sensitivity (4~74 times higher than with 5 mM ammonium formate). Addition of 10 (or up to100 mM) hydrochloric acid (HCl) in the sample diluent was crucial to keep response linearity for basic amino acids of histidine, lysine and arginine. Different HCl concentration (10~100 mM) in sample diluent also excreted an effect on detection sensitivity, and it is of importance to keep the final prepared sample and calibrators in the same HCl level. Leucine and isoleucine were distinguished using different transitions. Validated at seven concentration levels, accuracy was bound within 75~125%, matrix effect generally within 90~110%, and precision error mostly below 2.5%. Using this newly developed method, the free amino acids were then quantified in a total of 544 African indigenous vegetables (AIVs) samples from African nightshades (AN), Ethiopian mustards (EM), amaranths (AM) and spider plants (SP), comprising a total of 8 identified species and 43 accessions, cultivated and harvested in USA, Kenya and Tanzania over several years, 2013~2018. The AN, EM, AM and SP were distinguished based on free AAs profile using machine learning methods (ML) including principle component analysis, discriminant analysis, naïve Bayes, elastic net-regularized logistic regression, random forest and support vector machine, with prediction accuracy achieved at ca. 83~97% on the test set (train/test ratio at 7/3). An interactive ML platform was constructed using R Shiny at https://boyuan.shinyapps.io/AIV_Classifier/ for modeling train-test simulation and category prediction of unknown AIV sample(s). This new method presents a robust and rapid approach to quantifying free amino acids in plants for use in evaluating plants, biofortification, botanical authentication, safety, adulteration and with applications to nutrition, health and food product development.

Evaluation of radionuclide concentrations and average annual committed effective dose due to medicinal plants and soils commonly consumed by pregnant women in Osukuru, Tororo (Uganda)

The intention of the study was to establish the activity concentrations and the annual committed effective dose due to ingestion of medicinal plants and soils by pregnant women and their probable effects to infants. The samples of medicinal plants and soils were collected from Osukuru, Tororo District (Uganda). The naturally occurring radionuclides investigated were 226Ra, 232Th and 40K and their activity concentrations were determined using NaI gamma detector. In the medicinal plants, the average activity concentrations of 226Ra, 232Th and 40K were found to be 6.04 Bq/kg, 9.65 Bq/kg and 359.59 Bq/kg respectively. African Basil registered the highest activity concentration of 226Ra of 10.02 Bq/kg, spider plant had the highest activity concentration of 232Th of 18.60 Bq/kg whereas the pumpkin registered the highest activity concentrations of 40K of 437.92 Bq/kg. The average activity concentrations of 226Ra, 232Th and 40K in ‘medicinal soils’ were 68.87 Bq/kg, 78.20 Bq/kg and 477.44 Bq/kg respectively. The soils from the anthills registered the highest activity concentration of 226Ra and 40K while the one from bricks registered the highest activity concentration of 232Th.The annual committed effective dose due to the ingestion of medicinal plants varied from 0.096 to 0.297 mSv/y with an average of 0.194 mSv/y in infants, 0.016–0.040 mSv/y with an average of 0.029 mSv/y for individuals of age range 12–17 years and 0.007–0.018 mSv/y with an average of 0.013 mSv/y for individuals older than 17 years. Whereas the annual committed effective dose due to the ingestion of ‘medicinal soils’ varied from 1.28 to 1.65 mSv/y with an average of 1.46 mSv/y in infants, 0.23–0.30 mSv/y with an average of 0.26 mSv/y (12–17 years) and 0.07–0.09 mSv/y with an average of 0.08 mSv/y for individuals older than 17 years. In medicinal plants, the annual committed effective dose for the all age groups examined were below 0.3 mSv/y (maximum world permissible as reported UNSCEAR, 2000) while that due to the ingestion of ‘medicinal soils’ had values higher 0.3 mSv/y in infants. The results of this study show that there is inherent danger to the infants in consuming soils during pregnancy and this should be discouraged.

Indoor formaldehyde removal by three species of Chlorophytum comosum under dynamic fumigation system: part 2—plant recovery

Spider plants (Chlorophytum comosum) are known to be among the most common easy mountable indoor plants capable of purifying indoor air by absorbing carbon monoxide, formaldehyde, xylene, and many other hazardous gases. In addition, these plants are non-toxic and safe for pets and children. This project is focused on the investigation of the spider plants' capability of the formaldehyde purification under laboratory-controlled parameters of the indoor air environment. Two scenarios including employment of fresh plants as well as recovered ones damaged by 7-day exposure of formaldehyde were considered. A special attention was made to the investigation of physiological indexes of the plant leaves after damage, and whether the spider plant could be reused after its recovery. The physiological characteristics of the recovery period of potted Chlorophytum comosum immediately after 7 days of fumigation with formaldehyde were studied. Eight physiological indexes of leaves including chlorophyll, free protein, relative conductivity, MDA (malondialdehyde, lipid peroxidation), SOD (superoxide dismutase), POD (peroxidase), T-AOC (total antioxidant capacity), and stomata were selected to monitor plants' recovery processes. The results of 30-day experimental runs showed that three species of spider plants were mostly recovered within 15 days. Repeated 7-day fumigation of plants, conducted to study their ability to effectively clean the air after regeneration, confirmed such ability; the efficiency at the first day was similar to the performance of the fresh plant. However, from the second day, the efficiency was dropped by 35-50% and remained at these levels for the rest of the exercise.

Biofumigation efficacy of spider plant (Cleome gynandra L.) accessions on nematode control in tuberose (Polianthes tuberosa L.)

Tuberose (Polianthes tuberosa L.) is a perennial summer flower grown by smallholders in Kenya for export. However, its production and export volumes have declined drastically due to nematodes infestation. This study evaluated the effect of Cleome gynandra accessions on nematode management on tuberose. Experiment was conducted at the Horticulture Research Field, Egerton University, Kenya using a randomized complete block design with four replications. The treatments were: five accessions of C. gynandra namely ‘Simlaw’, ‘Egerton’, ‘Taastrup’, ‘PS’ and ‘IP8’, applied at 6 kg/m2 and compared with Brassica napus, solarization and untreated control. Data was collected on growth and yield parameters, nematode infestation and quality of tuberose. Data collected was subjected to analysis of variance at p≤0.05 and means separated using Tukey’s test. Biofumigation with Cleome gynandra accessions helped to reduce nematode population by 34%, gall numbers by 83% and galling index by be 96% when compared with the control. Use of biofumigation helped to improve plant height and leaf number of tuberose by 16% and 87%, respectively, when compared with the control. Use of biofumigation helped to improve spike length by 32%, marketable spikes by 80%, and flower yield by 90% and reduced nonmarketable spikes by 95% when compared with the control. Based on the above results, use of Cleome gynandra accessions and other biofumigants such as rape seed can be used to manage nematodes and improve growth, yield and quality of tuberose.

Isolation of Bile Salt Hydrolase and Uricase Producing Lactobacillus brevis SF121 from Pak Sian Dong (Fermented Spider Plant) for using as Probiotics

The interesting application of bile salt hydrolase enzyme is reduction of cholesterol in serum and amelioration lipid profile. While uricase enzyme can be applied to convert insoluble uric acid to be soluble form and excrete from the body. Probiotics are living organisms with generally know that they can provide beneficial effects to their host. Several reports show that probiotic bacteria with bile salt hydrolase and uricase can improve hypercholesterolemia and hyperuricemia patient. The novel isolate of Lactobacillus from Pak Sian Dong in this study is identified as L. brevis SF121 and probably use as probiotic bacteria in the future. However, this isolate still need further experiments to investigate and improve properties of probiotics. Moreover, this finding suggests that Pak Sian Dong or fermented spider plant can be designated as a good source for probiotic screening and also defines as health-promoting diet.

Perceptions of end-users in Limpopo Province (South Africa) about the Spider plant (Cleome gynandra L.)

Indigenous leafy vegetables such as the spider plant (Cleome gynandra L.) can play an important role in alleviating malnutrition and providing a source of income to smallholder growers. In South Africa, the spider plant is often harvested from the wild. There is lack of information regarding the perceptions of end-users about this indigenous leafy vegetable in many regions of South Africa. Therefore, this study was designed to evaluate the perceptions of local communities about the spider plant in Limpopo Province (South Africa). This information on the perception of spider plant by end-users will serve as a pre-requisite to establish a breeding programme, strategies to conserve the vegetable and to establish commercial production of this vegetable. Questionnaires were administered to households in each of the five districts in Limpopo Province targeting a wide range of end-users. Their consumption patterns, availability and level of knowledge of spider plant was assessed. Chi-square tests were used to assess the differences in perceptions and consumption patterns. The results showed that some of the communities relied on harvesting the vegetable spider plant from the homestead for consumption. There was no commercial seed production of this vegetable in these communities. The highest consumption (> 50%) of the vegetable was observed in Waterberg and Sekhukhune districts. The results also showed that the age of consumers influenced dietary preferences with the old people preferring this leafy vegetable more than the young people. The bitter taste of the vegetable appeared to deter some potential end-users. These results showed that there is potential to cultivate the spider plant as a crop and to improve the taste of the vegetable. In addition, good quality seed could improve the production of the vegetable.

Utilization of Spider Plants (Gynandropsis gynandra, L. Briq) amongst Farming Households and Consumers of Northern Namibia

Spider plants (Gynandropsis gynandra, L. Briq.) are a semi-wild vegetable reported to have high nutritional, medicinal, insecticidal, and cultural values, yet continue to be neglected in research. The study was undertaken to investigate indigenous knowledge and utilization of the species in five regions of northern Namibia. Three tools were used; (i) focus group discussion, (ii) semi-structured interviews involving a random selection of 100 farming households and 24 consumers, and (iii) key informant interviews involving four agricultural staff and two open-market supervisors. Data were subjected to descriptive statistics, inferential, and cluster analyses. The study found that farming households and consumers placed higher nutritional, sociocultural, and medicinal values in spider plants than any other vegetable. Ranking of utilization traits, such as nutritional, sociocultural, and medicinal use, revealed three clusters of sociolinguistic groups associated with geographical region. The vegetable was sold and used in most cultural, traditional, and religious functions as a relish, as a source of honor, to bring luck, and for protection. The diverse uses and value placed on spider plants could offer an opportunity for the development of technologies for enhancing their domestication, production, and utilization. It is recommended that follow-up studies be carried to identify specific sociocultural and geographic factors affecting the use of spider plants.

Natural variation in specialised metabolites production in the leafy vegetable spider plant (Gynandropsis gynandra L. (Briq.)) in Africa and Asia

The improvement and promotion of leafy vegetables, used for both food and medicine, benefits greatly from detailed knowledge of their health-promoting specialised metabolites. In the present study, we investigated the global metabolite variation in the leaves of 48 accessions of the leafy vegetable Gynandropsis gynandra using two complementary analytical platforms: liquid-chromatography mass spectrometry (LC-MS) for an untargeted comparison of non-volatile semi-polar metabolites and gas-chromatography mass spectrometry (GC-MS) for an untargeted comparison of volatile metabolites. Our results revealed large variation in 936 semi-polar compounds including flavonoids, terpene glycosides, glucosinolates and various phenolic compounds. Unsupervised multivariate analysis indicated the variation in levels of the semi-polar metabolites was mainly driven by geography, with accessions from both West Africa and Asia forming a group clearly separated from East African accessions. Detected volatile metabolites included various sesquiterpenes, aldehydes, ketones, and sulphur-containing isothiocyanates. Variation in these compounds was however not geographically specific, but most likely linked to the taste and aroma of the leaves. The relative abundance in glucosinolates and isothiocyanates in the leaves allowed the clustering of accessions into two main groups that could be used for further plant-herbivore interaction studies. This study revealed both the broad spectrum of phytochemicals present in Gynandropsis gynandra leaves and the substantial variation in metabolite profiles among accessions from different regions of the world. Our results provide a basis for the development of breeding programs aiming at improving the levels of specialised metabolites in this tropical leafy vegetable for increased resistance against pests and diseases and improved human health.

Effect of Spider Plant Accessions on Phenotypic Traits: Implications for Breeders and Farmers in Kenya

Spider plant (Cleome gynandra L.) is an important African leafy vegetable (ALV) that has been used by local African communities as a source of nutrition in their diets for many years. The plant has recently attracted an increasing demand for its highly nutritive and health-promoting bioactive compounds important in combating malnutrition and reducing human degenerative diseases. Despite the great value of the spider plant, its supply and cultivation remain low, a factor attributed to unavailability of superior genotypes. This study carried out at Ruiru Sub-county, Kiambu County in Kenya sought to establish the influence of genotypic variation on spider plant phenotypic diversity for future breeding and conservations. Experimental plots were set up in the field in Ruiru using split-plot design with three replications. Analysis of variance (ANOVA) was used to assess the significance of variables. Results indicated that genotypes MLSF3, UGSF36, UGSF14, and MLSF17 produced the highest number of flowers, large petioles, big stem sizes and large leaf area respectively. In conclusion, the study recommends the adoption of genotypes MLSF17, UGSF14, UGSF36 and MLSF3 by farmers considering their outstanding positive effect on phenotypic traits.

Potential of Bioelectricity Generation in Plant-Microbial Fuel Cells Growing House Plants

Although renewable sources of energy including geothermal, hydropower, wind, solar and biomass are utilized by the Philippines, coal-fired power plants remain the main source of electrical energy consumed by Filipino households. To lessen the nation’s dependence on fossil fuels, new and innovative sources of renewable energy should be explored. Plant-Microbial Fuel Cells (PMFCs) are a promising renewable energy technology that can be used to supplement our demand for electricity. PMFCs utilize the metabolic processes of certain bacteria in the roots of a plant to generate clean electricity. This study tested the potential of generating electricity from three common house plants in a PMFC set-up: Spider Plant (Chlorophytum comosum), Portulaca Flower (Portulaca oleracea), and Dumb Canes (Dieffenbachia amoena). A simple set-up was prepared using low-cost materials. Open circuit voltage and current was continuously monitored to determine the power output of the PMFCs. C. comosum registered the highest maximum power density out of the three plants, at 30.39 mW/m2. The results of this study has direct implications to how house plants are kept. Instead of keeping them for aesthetics, the added value of green energy produced can be valuable for powering devices in-situ.

Origin-dependence of variation in seed morphology, mineral composition and germination percentage in Gynandropsis gynandra (L.) Briq. accessions from Africa and Asia

BackgroundSpider plant [Gynandropsis gynandra (L.) Briq.], an economically promising African leafy vegetable, characterized for leaf yield components and nutritive quality, exhibits poor seed germination that hinders a wider expansion of the crop in urban and periurban horticultural systems. So far, there is little information pertaining to seed morphological traits and mineral elements content that may be associated with higher seed germination. This research investigated the hypothesis that spider plants from different geographical areas exhibited differences in seed mineral composition, morphological traits, and germination capacity. To this end, twenty-nine accessions of Gynandropsis gynandra from West and East-Southern Africa, and Asia were screened for variation in seed size (area, perimeter, length, width), 10-seed weight, mean germination time, germination percentage and mineral content variations. The scanning electron microscopy (SEM), light microscopy and energy dispersive spectroscopy (EDS) solution were used to study seed morphology and mineral composition.ResultsWe show for the first time the external and internal structure of the seeds of Gynandropsis gynandra and measured eight mineral elements, including carbon (C), oxygen (O), magnesium (Mg), aluminium (Al), phosphorus (P), sulphur (S), potassium (K) and calcium (Ca). The accessions differed significantly (p < 0.001) with respect to seed size (area, perimeter, length, width), 10-seed weight, mean germination time and germination percentage. The hierarchical cluster analysis based on fourteen variables grouped the accessions into three distinct clusters, partially dependent on their geographical origin. Asian accessions exhibited smaller seeds and recorded higher values in terms of germination percentage. West African accessions had bigger seeds but with lower germination percentage. Variation in minerals such as potassium, carbon, and calcium content showed different patterns according to geographical origins.ConclusionSmaller seeds in G. gynandra exhibited better germination capacity. The Asian germplasm is a potential source of cultivars with a higher germination percentage for improving seed quality in the species.

Mineral and Phytochemical Composition of Cleome Gynandra Methanolic Extract

The study was done to evaluate the mineral and phytochemical composition of the methanolic extract of Cleome gynandra (spider plant). The plant is used as a traditional vegetable in some communities in sub-Saharan Africa and Asia. The plant has also been reported to have some medicinal effect due to presence of phytochemicals but its pharmacological and phytochemical profile has not been fully established. Collection and authentication of the plant was done followed by extraction using methanol as a solvent. The phytochemical investigation was done using both chemical analysis and chromatography method by use of a Gas chromatography mass spectroscopy (GCMS) system as per standard protocol. Cleome gynandra was found to contain some mineral compounds of nutritional importance and phytochemicals with potential medicinal importance. The phytochemicals analyzed include saponins, flavonoids, tannins, alkaloids, cardiac glycosides, terpanoids and polyphenols. These different phytochemicals can be further studied and their potential medicinal importance analyzed. The study concluded that Cleome gynandra contains phytochemicals with potentially important medicinal value. The plant (Cleome gynandra) can also be used as an important nutritional source of some essential nutrients like Vitamin C and beta carotene. It can also be a good source of some mineral elements like iron, selenium, cobalt, copper, zinc and manganese. This can be important for families in rural areas and for the low-income households in both rural and urban areas as a source of nutrients.

Protein and energy contribution of African indigenous vegetables: Evidence from selected rural and peri-urban counties of Kenya

Although positive steps have been taken towards reducing food insecurity, it remains a serious and recurrent issue, especially in developing countries. Food insecurity is aggravated by the world’s growing population and global ecological changes and calls for novel agriculture-based hunger eradication strategies. It is argued that production and consumption of indigenous vegetables (IVs) enhances accessibility and availability of nutritious food in households. Indigenous vegetables (IVs) contain significant amounts of macronutrients and high levels of micronutrients. As their agro-economic advantages make them relatively easy for uptake by resource-poor households, they represent a direct solution to ‘hidden hunger’. Household-based survey data collected from 1232 IV producers in rural and peri-urban areas of five selected counties in Kenya in 2014 were used to examine the dietary contribution of IVs. Five priority indigenous vegetables were analysed: amaranth, cowpea, African nightshade, spider plant and Ethiopian kale. Quantitative analysis was performed using food security indicators from the ADePTFood security Module data analytical software. This study’s findings indicated African nightshade was the most consumed indigenous vegetable, providing the largest share of dietary energy consumption (average of 43 kcal/person/day). Amaranth was found to provide the highest share and cheapest source of dietary protein consumption, an average of 4.9 g/person/day, thus meeting 8% of the adult daily protein requirement. These results showed the clear dominance of indigenous vegetables over exotic vegetables in terms of protein contribution, achieved both by amaranth’s high protein content compared tocabbage, as well as the low per unit cost of protein in indigenous vegetables compared to exotic vegetables. Given that, IVs have a significant protein content that adds variety to staple diets at comparatively low median dietary unit values and that they are important sources of dietary energy, efforts should be made to increase their consumption by undertaking further research, raising awareness and instituting policies.

Growth, Photosynthesis, and Physiological Responses of Ornamental Plants to Complementation with Monochromic or Mixed Red-Blue LEDs for Use in Indoor Environments

Inch (Tradescantia zebrina) and spider (Chlorophytum comosum) plants were grown in a growth chamber for two months in plastic containers to evaluate the effects of different light treatments (TO Tube luminescent Dunn (TLD) lamps or control), TB (TLD lamps + blue light emitting diodes (LEDs)), TR (TLD lamps + red LEDs), and TBR (TLD lamps + blue and red LEDs) on biomass, photosynthesis, and physiological parameters. Total dry weight and water content were evaluated at the end of the experimental period. After two months, pigment concentrations and the photosynthetic rate were assessed in both species. The total soluble sugar, starch, and proline concentrations in the leaf as physiological parameters were studied at the end of the experiment. Both species had increased root, shoot, and total dry weight under blue LEDs conditions. The chlorophyll concentration showed a specific response in each species under monochromic or mixed red-blue LEDs. The highest photosynthetic rate was measured under the addition of mixed red-blue LEDs with TLD lamps. At the physiological level, each species triggered different responses with respect to total soluble sugars and the proline concentration in leaves under monochromic or mixed red-blue LEDs. Our study demonstrated that the addition of blue LEDs is advisable for the production of these ornamental foliage species.

Optimization of media and nutrition for foliage plants grown under modular vertical green walls

An investigation was carried out to study the performance of various media and nutrients for three foliage plants viz., arrow head plant (Syngonium podophyllum), boat lily (Tradescantia spathacea) and spider plant (Chlorophytum comosum) grown under modular vertical green walls. The experiment comprised of four media viz., coco peat, Greenosil, perlite and vermiculite and their combinations and two nutrients viz., foliar nutrition (NPK 19:19:19 and @ 1% twice (30 and 90 days after planting) and fertilizer stick (Greenstix sticks were inserted to the modular containers @ one per container at 30 and 90 days after planting). Results revealed that, among the media, plants grown under vermiculite showed better performance in exhibiting maximum values for plant height, leaf area, shoot weight, root weight and visual quality in all the three foliage ornamentals. However, among the nutrients, those plants inserted with fertilizer stick (N2) recorded highest for plant height, leaf area, shoot weight, root weight and visual quality in arrow head plant and spider plant. However, maximum values for plant height, leaf area, shoot weight and visual quality in boat lily were recorded under the treatment N1 (Foliar nutrient) except root weight. The interaction between media and nutrients was significant and plants grown under vermiculite and containers inserted with fertilizer stick showed superior performance w.r.t. all the characters in arrow head plant and spider plant, whereas, in boat lily, plants grown under vermiculite and plants sprayed with foliar nutrients showed better results.

Diversity and Domestication Status of Spider Plant (Gynandropsis gynandra, L.) amongst Sociolinguistic Groups of Northern Namibia

Knowledge on the diversity and domestication levels of the spider plant (Gynandropsis gynandra) has the potential to affect pre-breeding for client-preferred traits, yet information is scarce in Namibia due to limited research. We investigated indigenous knowledge on the species diversity and domestication levels in the regions of Kavango West, Ohangwena, Omusati, Oshana, and Oshikoto of northern Namibia. Semi-structured interviews involving 100 randomly selected farming households, four key informant interviews, and a focus group discussion were conducted. Descriptive and chi-square tests were conducted using IBM SPSS version 20. Out of the possible four morphotypes, the results suggested that only one with green stem and green petiole existed and was associated with soils rich in organic manure. Spider plant abundance was reported to be on the decline, due to declining soil fertility. On a scale of 0 (wild species) to 6 (highest level of domestication), an index of 1.56 was found and this implied very low domestication levels. Furthermore, the study found significant differences in the trends of domestication across the sociolinguistic groups (χ2 (12, N = 98) = 46.9, p &lt; 0.001) and regions studied (χ2 (12, N = 100) = 47.8, p &lt; 0.001), suggesting cultural and geographical influences. In conclusion, the findings constituted an important precedent for guiding subsequent pre-breeding efforts.

Determining Benzene Concentration Safe Level at Gas Stations in Pancoranmas Depok, Indonesia

Benzene is a dangerous chemical compound contained in Gas Station product. It is one of components in gasoline containing carcinogens. Gas station workers are prone to the risk of benzene due to continuous exposure, which can endanger their health and safety. This study was aimed to determine benzene concentration safe level at gas stations in Pancoranmas, Depok. The design of this study was article review based on reviews of previous studies that were then analyzed. The result of the study showed that benzene concentration safe level limit at gas stations in Pancoranmas, Depok, based on the calculation done was 0.3 ppm. This value was different from the values set by international and national institutions such as OSHA, NIOSH, ACGIH, ATSDR, the Indonesian National Standardization Agency and the Ministry of Manpower and Transmigration of the Republic of Indonesia. Therefore, reviews are needed to provide health and safety guarantees for the gas stations’ workers. The control recommendation for the gas stations’ workers exposed to benzene was the provision of Personal Protective Equipment (PPE) in the form of respirator organic vapor to minimize benzene exposure and green open space by planting a number of ornamental plants to absorb and reduce benzene exposure such as Spider Plant, Boston Fern, Peace Lily, Dutch Beteland Golden Pothos.

Drying and colour characteristics of Cleome gynandra L. (spider plant) leaves

Abstract Drying characteristics of Cleome leaves in an oven dryer was studied. The impact of oven drying temperature (50, 60 and 70 °C) on moisture composition of the plant at a uniform air speed was considered. Eight drying models, namely, simple exponential, Page, Verma, modified Henderson and Pabis, Lewis, two term exponential, Newton, logarithmic, and Wang and Singh were fitted to drying data. Modified Henderson and Pabis model satisfactorily depicts the drying behaviour of Cleome leaves. Effective moisture diffusivity of Cleome ranged from 1.03 × 10−6 to 1.77 × 10−5 m2/s. Reliance of the calculated effective diffusivity on oven temperature was unavoidable. The required activation energy for oven drying of Cleome leaves was found to be 24.46 kJ/mol. The colour characteristics of Cleome leaves in terms of L*, a* and b* were determined. Based on the colour characteristics results, drying condition of 70 °C 90 min was found to be optimum for oven drying of Cleome leaves.

English

Cleome gynandra L. is one of the traditional leafy vegetables in Africa and Asia providing essential minerals and vitamins to the diet and income of resource poor communities. Despite these benefits, the crop has not been studied extensively resulting in lack of scientific information to guide crop improvement research and associated agronomic practices. The taxonomy of the crop, its reproductive behaviour, genome size, ploidy level and origin are neither readily available nor well understood. This paper reviews existing literatures in these areas to provide information for future research and development of the crop. Reading the review, one could appreciate the taxonomic classification of the genus is still under debate despite recent molecular studies that placed the crop in the Cleomaceae family as opposed to previous studies that classified it under Capparaceae family. According to present review the crop belongs to the Kingdom of Plantae, Phylum spermatophyta, Division Magnoliophyta, Class Magnoliopsida, Order Brassicales and the Family of Cleomaceae. Different genome sizes of C. gynandra have been reported which still warrant further investigation. Various studies reported different ploidy levels including diploid, triploid and polyploid indicating the need of further investigation to clarify the taxonomy, genome size and ploidy level(s) of the crop. Key words: Chromosome, genome size, indigenous leafy vegetables, morphology, ploidy level, spider plant. &nbsp

Regional invertebrate cross- and within-taxon surrogacy are scale and taxon dependent

This study measured within- and cross-taxon congruence in the diversity of epigeal invertebrates (spiders, beetles and millipedes) and woody vegetation sampled at small spatial grains (0.25 ha) across a large area (30 000 km2) within the Vhembe Biosphere Reserve (VBR) in South Africa. Beetle, spider, millipede and woody plant diversity was recorded at 160 point localities in 20 sites stratified across the dominant vegetation types of the VBR. Surrogacy relationships were explored using multiple linear regression (species richness) and Mantel tests (composition), while complementarity was analysed using the species accumulation index (SAI). Very little (< 10%) of the variation in invertebrate species richness was explained by woody vegetation richness alone, but the relationship improved when vegetation type was added to the regression, especially for beetles. Woody vegetation assemblages showed a positive but weak congruence with beetle assemblages, especially Tenebrionidae. Woody vegetation assemblage showed poor congruence for spider communities in general, with the exception of Lycosidae. Although cross-taxonomic congruence was observed between woody vegetation and invertebrate taxa, the relations based on SAI were stronger than expected for Coleoptera (Carabidae, Scarabaeidae and Tenebrionidae), positive but weak for spiders (all families), and weak for millipedes which had several localised endemics. Tests of higher taxonomic categories as surrogates were shown to have much greater potential than cross-taxon surrogacy. Genera in particular are excellent surrogates for species. Tribal- or generic-level determinations can be a cost-efficient approach for regional conservation planning exercises which aim to represent smaller scale variations in invertebrate diversity.