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The purpose of this paper is to study the structure‐activity correlation of four medicinal plants – Ocimum basilicum L., Piper betle L., Grewia asiatica L., Lantana camara L. in crude methanolic extract. These plants have been used in Ayurvedic preparation as alternative medicine. The contents of phenolic compounds (flavonoids, anthocyanin) and antioxidant capacities were evaluated.

Folin‐Ciocalteu method was used for the analysis of the phenolic compounds. Total flavonoids were also evaluated. DPPH, ABTS+, FRAP and H₂O₂ assays were used to evaluate antioxidant activity. Most of the assays were determined spectrometrically.

O. basilicum L. had the highest of total phenolics content (305.11 mg GAE/g), highest content of anthocyanins (15.427 mg/Kg) and total flavonoids (9.692 QE mg/g). The DPPH, ABTS+, FRAP and H₂O₂ assay indicated that these plants possessed considerable antioxidant activities.

The results also showed that O. basilicum and L. camara from red colored cultivars possessed high contents of phenolic compounds. FRAP assay showed AOA in the following sequence – Lantana camara>Ocimum basilicum>Piper betle>Grewia asiatica. Since L. camara showed highest antioxidant capacity thus it can be a potential resource for commercial antioxidant.

The purpose of this research is to identify and investigate some natural dyes with halochromic properties for potential use as food spoilage indicators to reduce waste and curve the negative effects of food borne diseases.

Exactly 10 potential dye-yielding plants were selected based on their colour (mostly purple, red, maroon and pink). Solvent extraction was used to extract the dyes and pH differential method was used to determine the concentrations of anthocyanin in the extracted dyes. Different concentrations of hydrochloric acid and sodium hydroxide (0.1 M, 1 M and 2 M) in drops and in excess as acidic and basic solution, respectively, were used to test the halochromicity of the extracted dyes. Methyl red (a synthetic dye) was used as a reference standard/control. The pH of the dyes was recorded before and after addition of both NaOH and HCl solutions.

Five out of the 10 dyes extracted (labelled as dye A–E for Ti plant (green Cordyline fruticosa), coleus (Coleus blumei), paper flower (Bougainvillea glabra), painted nettle (Palisandra coleus) and purple heart (Setcresea purpurea), respectively, were found to be halochromic (even at low doses) by changing its colour when exposed to both acidic and basic solutions. While other dyes labelled F–J for red acalypha (Acalypha wilkesiana), golden shower (Cassia fistula), golden dew drop (Duranta repens), wild sage (Lantana camara var Aculeata) and pink oleander (Apocynaceae Nerium oleander), respectively, were either completely insensitive to the solutions in drops, slightly sensitive at high doses or the colour change is insignificant. Although some dyes were found to be more sensitive than others but in most cases, the colour changes in halochromic dyes were more stable in acidic conditions than in basic making it more sensitive to the basic than the acidic solution with the exception of dye A and E (to some extent) which was sensitive to both acidic and basic solution. The anthocyanin contents of dye A–J were found to be between the range of 2.28–10.35 mg/l with dye E having the lowest and dye J with the highest anthocyanin concentration, respectively. The initial pH of all the dyes falls within the range of 4.8–7.3 with most found within the acidic range.

Halochromic dye research studies are still at the infancy stage in developing world despite the vast available and abundant potential natural halochromic dye-yielding plants. The study explored this area of research and gives an opportunity for the development of smart packaging for pH-sensitive foods using natural dyes as an alternative to conventional synthetic dyes to reduce cost and also curve the negative effect of synthetic dyes as well as food borne diseases.

The purpose of this paper is to outline and reflect on the new research agenda for the Great Zimbabwe World Heritage property. This research agenda was jointly developed by academics and practitioners from Great Zimbabwe University (GZU) and the National Museums and Monuments of Zimbabwe (NMMZ) respectively. This Research-Practice Team was put together for the Heritage Place Lab (HPL), a pilot project of the ICCROM-IUCN World Heritage Leadership programme.

A series of steps were undertaken to come up with research priorities and a new research agenda that are presented in this paper. The HPL project involved online workshops, due to the COVID-19 travel restrictions, that were held between September 2021 and April 2022. The HPL methodology involved six assignments that were based on the Enhancing Our Heritage Toolkit 2.0 (EOH) which was being designed by UNESCO and its Advisory Bodies. This toolkit encouraged the team to establish site-specific management issues and research needs. The toolkit helped the team to have a detailed appreciation of the site's Outstanding Universal Value as well as other heritage values of national and local importance. The toolkit also involved the mapping of site attributes and multiple actors as well as the analysis of governance and legal frameworks. The toolkit also required the team to identify factors affecting the heritage property.

The Research-Practice Team highlighted challenges that resulted from the legacy of ill-informed research activities and conservation efforts at the World Heritage property. It became more apparent that the site managers were prioritizing the physical fabric of the site at the expense of the spiritual aspects. Lack of coordination among the actors was also undermining the governance structure. Four thematic strands which included local values and intangible cultural heritage elements; heritage governance; climate change and environmental sustainability and incorporation of local knowledge systems were identified for further research.

The paper is an outcome of collaborative efforts that were done by academics and practitioners. Researchers and site managers at Great Zimbabwe had hitherto worked in silos. The majority of previous and ongoing research on the World Heritage property falls short of addressing the dire management challenges. The paper is an attempt to broaden the scope in terms of the management of the site. In the past focus has been on the monumental aspects of the site with specific reference to the dry-stone walled structures. However, in this instance, the Research-Practice Team has integrated new interests such as the intangible aspects of Great Zimbabwe, spirituality and community beneficiation.

The selection of wavelength region and number of bands is a research problem for remote sensing experts for utilization of data provided by the sensor system. The present study proposes to make an evaluation for optimum band selection and classification accuracy.

The entropy, brightness value overlap index (BVOI), optimum index factor (OIF) and spectral separability analysis, i.e. Euclidean distance (ED), divergence, transformed divergence (TD) and Jefferies‐Matusita (JM) distance and accuracy of MLC classification were carried out. For the present study Terra ASTER, Landsat ETM⁺ and IRS 1D LISS III dataset has been used. The first three methods were for the spectral evaluation of the three satellite data used and for determination of information content, variance and spectral overlap among the classes present in the natural and man‐made landscape. The fourth method is for selection of spectral band combinations with highest separability of classes using divergence matrices. These band combinations are selected for the classification and subsequent accuracy assessment.

The OIF values are clearly indicating that the performance of ASTER data is the best, having the lowest correlation between the bands; hence the separability of the feature is also highest, while LISS III have shown high correlation between the bands, with the poor separability of the features. Landsat ETM⁺ data are in between these two sensors, better than LISS III but poorer than ASTER. The BVOI outputs of the three datasets of man‐made landscape show that band 3 of ASTER has the least overlap of the classes, followed by band 4 of ETM⁺. Very high overlap of the classes has been found in LISS III data. It has been found from spectral separability analysis of all the three datasets for the man‐made landscape that ASTER data with band combination of spectral bands 123468 contains the highest value of all the measures of spectral separability, i.e. ED (291.72), divergence (2,133.37), TD (2,000.00) and JM distance (1,414.10).

It can be inferred from the present study that spectral resolution plays a very important role in discrimination of vegetation features. ASTER data which are with the highest number of the bands amongst the satellite data used had shown highest classification accuracy, while LISS III data with lowest number of bands had shown lowest accuracy, and Landsat ETM⁺ stood in between the two sensors.

It is important to evaluate the sensor systems and their spectral regions for discrimination of vegetation features. The number of bands present in a particular sensor and the spectral regions used in it are some of the crucial factors which decide the usefulness of the data for different applications, including vegetation‐related studies. The selection of spectral wavelength region, i.e. spectral bands and the sensor system, presents the research problem for remote sensing experts to suggest the best spectral regions and satellite sensor for the discrimination of the vegetation features in different landscapes, namely man‐made and natural.

In the present study all the three datasets are extensively examined and tested for their vegetation discrimination capabilities using well‐established methodologies. All the parameters applied on the datasets revealed that spectral resolution definitely plays a role in the performance of the data as far as discrimination of features is concerned both in natural and man‐made landscape with desirable accuracy.

The purpose of this paper is to illustrate that campus and urban landscaping has important connections to biodiversity conservation, perceptions of natural heritage, sense‐of‐place, ecological literacy and the role of campus landscapes in the larger community. It also aims to show how campus landscapes express values and perform as a teaching, research and outreach resource.

The paper was written as a literature review applied to a case study. Drawing on E.O. Wilson's idea that society must assign the same value to natural heritage as it does cultural heritage to successfully safeguard biodiversity for the long haul, the paper argues that by altering key elements of human landscapes in strategic places – campus landscapes in this case – to reflect a deep appreciation of natural heritage, we can help shift worldviews to foster real sustainability. It also raises a set of questions based on popular perceptions and some challenges based on the broad literature, then shows how the case study performed in addressing the questions and meeting the challenges.

Stetson University's project helped push the campus' nascent green movement beyond the remedial and reactive approaches too often seen in most regions to a proactive, holistic campaign.

The paper should inspire other campuses and organizations to proactively manage landscapes for natural heritage education, biodiversity conservation, and sustainability, just as the featured case study has done in its larger community.

In the world of campus sustainability, biodiversity often takes a backseat to energy use, resource consumption and waste management. The paper calls attention to this shortcoming and in so doing hopefully will encourage research and applied projects to address the biodiversity crisis and the role that universities play.

The purpose of the paper is to analyze the different modes of species dispersal and the various types of alien species dispersed in the Indian peninsular region and its impact on the eco system and livelihoods.

The paper portrays the various identified alien species, the scale of invasion thereby resulting in biological disaster caused by mankind.

The paper lists the invasive alien species (IAS) are those that are transmitted from their own ecological niche and to a new niche due to human influence, which causes the biodiversity disaster. International boundaries are indeed porous to the intentional and unintentional movement of species from various eco systems in the country.

It is felt that few initiatives are being taken by International Union for Conservation of Nature (IUCN) and governance of eco system from IAS is a necessity. Sustainable eco system governance (SESG) from invasive alien species should be emphasized to avoid biodiversity disasters that will have an impact on food security and nutrition of human beings.

This study/paper aims to evaluate the floral richness of the central part of Chattogram city, Bangladesh. Chattogram is recognized as the largest port city and the commercial capital of Bangladesh, which confronts faster urbanization and swift infrastructure development. Green spaces in and around Chattogram city are shrinking sharply, which resulted in rapid loss of floral and faunal resources in this area. The present study was carried out from February 2018 to January 2019 to enumerate the vascular plant species of the Sulakbahar ward located in the central part of Chattogram City, Bangladesh.

The study area was categorized into 10 habitats to assess the variation of floral composition. The extensive whole area survey method was applied to record the flora from all sorts of plant habitats of the research area.

The study enumerated 418 vascular plant species under 315 genera and 120 families including natural, planted and cultivated from the study area. The habit form of the recorded plant composition indicated that herbs (35%) constitute the major plant category followed by trees (34%), shrubs (17%), climbers (12%), ferns (1%) and orchids (1%). The study also indicated that exotic species (50.3%) became dominant than native species (49.7%) in Chattogram city because of their scenic beauty, easy propagation and ornamental value to the city planners and inhabitants.

It appeared that floral resources of the Chattogram city area are in great threat due to aggressive and unplanned infrastructure development for housing, offices and institutions by replacing the green spaces. The study recommended that urgent protection measures should be taken to conserve and protect the existing floral resources for the well-being of the urban people.

The purpose of this paper was to determine the antifungal activities of different solvent extracts of common plants in vitro and in vivo against banana anthracnose fungus Colletotrichum musae (Berk & M.A. Curtis) Arx, and to investigate its effects on the pathogen and identify the bio active component(s).

Extracts were obtained from leaves, tender shoots, rhizomes, bulbs, seeds and fruits of 42 naturally growing plant species following hot sequential extraction. Preliminary screening of the solvent extracts was done based on the inhibition of radial mycelial growth of C. musae following poison food technique and conidial germination inhibition by cavity slide technique. The selected extracts were assessed for their effect on harvested banana in reducing anthracnose during storage. The active components in the bio-active fractions of plant extract were identified by gas chromatography-mass spectroscopy.

Methanol extracted a larger quantity of material (between 6.9 and 12.5 per cent) than hexane or chloroform, and all its extracts were active against the test pathogen with mycelial growth inhibition ranging from 13.70 to 88.89 per cent. Zingiber officinale rhizome extract as well as Polyalthia longifolia and Clerodendrum inerme leaf extracts exhibited more than 80 per cent inhibition of mycelial growth. Total inhibition of spore germination of C. musae was recorded in Z. officinale and P. longifolia extracts at 0.3 per cent w/v and 0.5 per cent w/v concentration, respectively, while only 68 per cent spore inhibition was recorded in C. inerme at 0.5 per cent w/v concentration. Of the three plant species, Z. officinale had the best antifungal activity (18.0 per cent disease incidence; 2.2 disease severity scale) when banana fruits were dipped in the extract at a concentration of 0.5 per cent w/v at 5 days of storage in ambient condition (80-82 per cent R.H., 27 ± 1°C). The bio-active compounds in the extract of Z. officinale were identified as alpha-curcumene and zingerone.

Based on the antifungal activity, plant extract of Z. officinale can be used as an effective alternative to chemicals in controlling anthracnose pathogen in harvested banana.

The purpose of this study is to extract and characterize a novel natural dye from the leaves of Lannea coromandelica and the extraction with finding ways of dyeing cotton fabric using three mordants.

The colouring agents were extracted from the leaves of Lannea coromandelica using an aqueous extraction method. The extract was characterized using analysis methods of pH, gas chromatography-mass spectrometry (GC-MS), Fourier transform infrared (FTIR), ultraviolet-visible (UV-vis) and cyclic voltammetry measurement. The extract was applied to cotton fabric samples using a non-mordant and three mordants under the two mordanting methods. The dyeing performance of the extracted colouring agent was evaluated using colour fastness properties, colour strength (K/S) and colour space (CIE Lab).

The aqueous dye extract showed reddish-brown colour, and its pH was 5.94. The GC-MS analysis revealed that the dye extract from the leaves of Lannea coromandelica contained active chemical compounds. The UV-vis and FTIR analyses found that groups influenced the reddish-brown colour of the dye extraction. The cyclic voltammetry measurements discovered the electrochemical properties of the dye extraction. The mordanted fabric samples showed better colour fastness properties than the non-mordanted fabric sample. The K/S and CIE Lab results indicate that the cotton fabric samples dyed with mordants showed more significant dye affinities than non-mordanted fabric samples.

Researchers have never discovered that the Lannea coromandelica leaf extract is a natural dye for cotton fabric dyeing. The findings of this study showed that natural dyes extracted from Lannea coromandelica leaf could be an efficient colouring agent for use in cotton fabric.

–Prosopis juliflora is a raw material for long-term sustainable production of bioethanol. The purpose of this paper is to identify the best combination of pre-treatment strategy implemented on the lignocellulosic biomass Prosopis juliflora for bioethanol production.

Pre-treatment of lignocellulosic material was carried out using acid, alkali and sonication in order to characterize the biomass for bioethanol production. Prosopis juliflora stem was subjected to steam at reduce temperature (121°C) for one hour residence time initially. Further acid and alkali treatment was carried out individually followed by combinations of acid and sonication, alkali and sonication. Sodium hydroxide, potassium hydroxide, hydrochloric acid, sulphuric acid and nitric acid were used with 3 per cent (w/v) and 3 per cent (v/v) concentration under temperature range of 60-90°C for 60 min incubation time. Sonication under 60°C for 5 min and 40 KHz frequency was carried out. Pre-treated sample were further characterised using field emission scanning electron microscope and Fourier transform infrared spectroscopy to understand the changes in surface morphology and functional characteristics.

In sono assisted acid treatment-based method, nitric acid yields better cellulose content at 70°C and removes lignin that even at increased temperatures no burning was observed.

The paper adds to the scarce research available on the combination of auto hydrolysis coupled with sono assisted acid/alkali hydrolysis which is yet to be practiced.