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This review aims to quantify the impact of calcium chloride in cementation solutions on Microbial Induced Calcite Precipitation (MICP). Specific soil strength properties, such as the Unconfined Compressive Strength (UCS) test, permeability (k) and calcium carbonate content of the soil, form the basis of quantifying the test results. Relevant articles from various online databases such as Scopus, Science Direct, ProQuest Dissertations and Theses Global (PQDT), Mendeley and Google Scholar are obtained with search strings of suitable keywords. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) were used to screen and select related articles based on exclusion and inclusion characteristics. This review shows a positive correlation between calcium concentrations and soil strength properties, where higher concentrations of calcium solutions induce stronger bonding between soil particles due to better calcite precipitation. However, we also note a reversed correlation when the concentration of calcium solutions is higher than 1 M. This review also verifies that the MICP process enhances soil strength using optimum calcium chloride concentration to avoid soil brittleness. This result benefits other fields, such as agricultural and soil engineering.

Intertidal gastropods, Faunus ater (F. ater), were collected from four sampling sites in Peninsular Malaysia. It was found that the concentrations of Zinc (Zn) (mg/kg dry weight) ranged from 347.23 to 356.21 for Digestive Caecum (DC), 95.00 to 100.91 for foot, 102.73 to 109.00 for muscle, 42.73 to 177.72 for operculum, 87.57 to 161.76 for remainder, and 24.42 to 53.96 for shell of F. ater. Current results indicate that the intertidal waters of Pantai Sri Tujoh has a higher bioavailability of Zn and require further research. According to the current findings, F. ater may be employed as a biomonitor of Zn pollution and bioavailability.

Oil palm (Elaeis guineensis) is one of the most nutrient-intensive plantations in Malaysia. It requires many nutrients to reach its full potential and production stage. The main issue is that nutritional stress is a crop health issue caused by a lack of nutrient components to sustain crop growth requirements. We aimed to review the nutrient deficiency of oil palm based on an observation and literature study. The leaflet of the oil palm tree was analyzed for this study. The result showed that nutrient deficiency in oil palm is a common issue. Since oil palm is a heavy feeder plant that requires a well-balanced supply of nutrients, the continuous use of sustainable (eco-friendly) biofertilizers at a cost-effectively optimal level is necessary to achieve the maximum yield of oil palm. Though there are some inevitable causes of nutrient deficiencies, good management program should be carried out to lessen this problem and improve oil palm health and production.

Background: Rural and urban people in Nigeria made use of medicinal plants as their curative measures, based on their ancient belief that propounded the authenticity of these plants in treating ailments.Materials and methods: Data were collected through semi-structured questionnaires across the study area (3senatorial districts),The collected plant species were authenticated and given voucher numbers, and the demographic data was subjected to Chi-square (x2) comparisons using SPSS version 22.Results: The major family among the surveyed plants, were Fabaceae (dominant), followed by Anacardiaceae and Combretaceae. Moreover, out of 97 respondents, 81 were male (83.5%) and 16 were female (16.5%). It was observed that respondents that were 41-50 years were many into practice ( p = 0.13. The majority of the respondents as compared using chi-square across the parameters, were illiterates (p = 0.06), and very few had a formal training or exposed to workshops (p = 0.02), while the majority inherited and utilized herbal medicine practice as their main sources of income (p = 0.04). The fidelity levels ranged as follows: For diarrhea (18.5% -100%), dysentery (11.11- 45%), pile (11.11 – 50%) and, ulcer covered 9.1% -100%. The ailments were in the range of 0.69 – 0.75 factors of informant consensus. Plant species with RFC values of 0.34, 0.27 and 0.21 as well as those with 0.1, were regarded to have the highest RFC values.Conclusion: Information collected were mainly on cases of gastrointestinal ailments and first of its kind on the use of medicinal plants in Yobe State, Nigeria.

The invertebrate species play different roles above and below ground in a soil ecosystem. They are also responsible for a complex interaction, which is manifested in soils as self-organized systems of different sizes and functions. These invertebrates are sensitive to any changes in land management activities and soil physio-chemical properties. Therefore, the current study aims to examine the ecosystem functions of soil invertebrates from different agriculture fields and establish the relationships of soil physio-chemical properties. Soil samples were collected from four different fields: three are from the main campus, namely Universiti Putra Malaysia (Center of Environmental and Forensic Studies (CEFS), papaya and organic farm), and one is from Nilai, Negeri Sembilan. The soil physical properties, such as moisture, temperature, particle size, bulk density, and soil porosity, were recorded. Soil chemical properties (EC, pH, total C&N, C/N ratio, organic matter, extractable P, Ca, Mg, K, and Na, CEC) were also determined. Pitfall traps and Berlese funnel were used as sampling methods. The invertebrates were stored in 70% ethanol and identified using soil invertebrate morphological classification, which was classified based on body size and biological functional groups. Macrofauna composition in the papaya farm was abundant from other sites at 80.44%, and ecosystem engineers comprised 39.56%. By contrast, mesofauna was abundant with 43.22% in organic farms, and litter transformers were abundant in CEFS at 54.05%. Meanwhile, microfauna was high in organic farms at 2.85%. Predatory populations were also high in Nilai farm at 49.29%. The CCA analysis showed that the physical and chemical properties of soil influence soil fauna density and diversity. The present finding concludes that the activities of ecosystem functions of soil invertebrates were considerably affected by agricultural and management activities

This paper summarizes the use of museum of biological collection (MBC) in comparison of chemical contaminants between the past and the present specimens. It is inferred that MBC provides a unique and crucial insight into the spatio-temporal trend of environmental contamination by establishing a historical reference point.

There are many biomonitoring studies of nickel in the mollusks, but to understand how the nickel is accumulated in the human body and the health risk posed by the metal is not a straightforward formula. Therefore, the aim of this paper is to draw a conceptual model of nickel content in the bodies of invertebrate mollusks and their gastrointestinal absorption of nickel. This model is useful to understand how nickel accumulation in the tissues of the mollusks could affect the nickel oral ingestion pathways. This conceptual model can shed some light on the mechanisms of nickel that may cause various toxicological risks and target cancer slope formulation in the future.

Fusarium fruit rot caused by fusarium species pathogens can be considered a threat to economic loss. The use of synthetic antifungals to control the pathogens has failed to the development of resistance of pathogens. Previous studies reported that plant extracts may contain various bioactive constituents that are able to control pathogen growth. Hence, the aims of this study are to examine the inhibition activity of some plant fresh extracts on mycelial growth and morphological changes of Fusarium oxysporum, F. proliferatum, and f. solani, causal agents of Fusarium fruit rot. Aqueous extract of selected plants was evaluated for their inhibition activity against all the three fusarium pathogens under in vitro condition using poisoned food bioassay. Averrhoa bilimbi fruit extract demonstrated a highly significant effect against mycelial growth of the pathogens with fungal inhibition percentage of 80.51% for F. oxysporum, 61.28% for F. proliferatum and 58.97% for f. solani. The results showed that the highest formation of 100% extract has lowered the conidia concentration and germination percentage of F. oxysporum (35.43%), F. proliferatum (47.61%), and f. solani (38.67%) compared to the control. Significant shriveled mycelia were observed via scanning electron microscope (SEM) on the pathogens treated with a. bilimbi extract, indicating morphological changes occurred in the cell membrane compared to the control in which the mycelia were in normal form. This innovation, which can be prepared and applied at home, has the potential as an eco-friendly and a benign approach to control fruit rot pathogen.

The rising concern regarding the negative impact of synthetic pesticides has led to the search for alternative means of pest control. Vermicomposting the mixture of oil palm empty fruit bunch and neem (Azadirachta indica) leaves, with the latter known to have pesticidal value, is therefore of great interest and significance to be studied. The present study was conducted to evaluate the chitinase, protease and β-1,3-glucanase activity of neem leaf-based vermicompost as an indication of its biocontrol properties. The total microbial population of different composition of the vermicompost was also investigated. The results showed that at 10% neem composition, an increment in microbial population, chitinase and protease activities was observed in the end product. A higher concentration of neem exerted a suppressive effect on the microbial population as well as enzymatic activity. This study suggested that the addition of an appropriate composition of neem leaves as one of the raw materials for vermicomposting would potentially enhance the performance of vermicompost as biofertilizer as well as biopesticide.

Microbial-induced calcite precipitation (MICP) is a natural process that offered various applications in the engineering field materials and construction industry. It has recently emerged as an innovative, eco-friendly, and economically engineeredprocess. One of the successful MICP methods of improving the engineering properties of soils is ureolysis. The ureolysis drove the process of precipitate calcite which binds soil particles within the soil matrix thus enhance soil characteristicssuch as stiffness, permeability, hydraulic conductivity, shear strength, and compressive strength. This paper aimed at reviewing the concept of utilizing calcium carbonate (CaCO3) precipitation by ureolytic bacteria towards the improvement of soil and sand engineering properties for various geotechnical applications. The potential applications of this technologyin soil erosion, stability, and reinforcement were discussed. Detail overviews of the temperature, pH, bacteria cell concentration, nutrients, types of bacteria, and concentration of reactants that affect the efficiency of the process are also reviewed. This review demonstrated the potential of the MICP technology from the laboratory to a field-scale or commercial applications.

Crepidium amplectens and Crepidium lowii are reported as two newly recorded Crepidium species belong to sect. Commelinodes from Peninsular Malaysia. The taxonomic affinity is discussed and validated involving another two of their complexes, Crepidium micranthum and Crepidium rheedei subsp. rheedei, to which they share some similar characteristics of the leaves and flowers. The comparative study was conducted based on a comprehensive description and clear photographic evidence of the macro-morphology and surface micro-morphology of the labellar and gymnostemium parts. This paper emphasizes the usefulness of diversity and distribution of ultrastructures and epicuticular sculpturing of the reproductive parts in delimiting the confusable and sympatric Crepidium species, and a brief note on the nectar or reward secretion in the genus with inference on the ecological adaptation and pollination strategies. Macro-morphologically, C. amplectens differs from C. lowii in having the leaves smaller, greenish and widely ovate. Individually, both species can be differentiated from C. micranthum based on the smaller flower and shorter labellum auricles, and inconspicuous gymnostemium stelidia. Micro-morphologically, C. amplectens is also distinguishable from C. lowii by having different diversity and distribution of the epicuticular ornamentation and papillae on the labellum and gymnostemium. Also, amongst the four studied species, only C. lowii has nectarostomata, occurring on the fovea or nectary.

Background: Rural and urban people in Nigeria made use of medicinal plants as their curative measures, based on their ancient belief that propounded the authenticity of these plants in treating ailments. Materials and methods: Data were collected through semi-structured questionnaires across the study area (3senatorial districts),The collected plant species were authenticated and given voucher numbers, and the demographic data was subjected to Chi-square (x2) comparisons using SPSS version 22. Results: The major family among the surveyed plants, were Fabaceae (dominant), followed by Anacardiaceae and Combretaceae. Moreover, out of 97 respondents, 81 were male (83.5%) and 16 were female (16.5%). It was observed that respondents that were 41-50 years were many into practice ( p = 0.13. The majority of the respondents as compared using chi-square across the parameters, were illiterates (p = 0.06), and very few had a formal training or exposed to workshops (p = 0.02), while the majority inherited and utilized herbal medicine practice as their main sources of income (p = 0.04). The fidelity levels ranged as follows: For diarrhea (18.5% -100%), dysentery (11.11- 45%), pile (11.11 – 50%) and, ulcer covered 9.1% -100%. The ailments were in the range of 0.69 – 0.75 factors of informant consensus. Plant species with RFC values of 0.34, 0.27 and 0.21 as well as those with 0.1, were regarded to have the highest RFC values. Conclusion: Information collected were mainly on cases of gastrointestinal ailments and first of its kind on the use of medicinal plants in Yobe State, Nigeria.

Metabolic changes in plants may serve as an early signal for infection in response to pathogen intrusions. In this study, metabolomic fingerprinting analysis was conducted on banana plantlets inocu...

Marine clay soils are problematic soils in the construction industry when they are subjected to construction loads. When these soils are loaded, they lose their structure. This leads to the soil being unable to withstand loads of any magnitude without exhibiting significant, permanent deformations. In order to stabilize the marine soil, new methods for soil improvement were built upon biogrouting by incorporating physical, biological and chemical treatments into the soil. However, the biggest challenge of this method is the bacteria migration through the soil medium. To overcome this issue, the electrokinetic phenomenon can be utilized alongside biogrouting to prevent the bacteria migration. In this regard, the present study applied electrobiogrouting stabilization to investigate the improvement of acidic marine clay soil with a pH of 3.69. To accomplish this, two large-scale physical models with dimensions of 500 × 300 × 1200 mm were fabricated to examine the influence of two different treated distances between the inlet and outlet—450 mm (D45) and 600 mm (D60)—on the stability of the treated soil. It was observed that the shear strength of the treated soil improved significantly. The shear strength at the D45 treated distance increased from 3.65 kPa (untreated soil) to 28.14 kPa (treated soil). However, the strength increased by increasing the treated distance. In addition, compressibility and soil electrical conductivity were reduced significantly, and the Atterberg limits were significantly enhanced from OH to OL. The reasons for the enhancement of treated soil were the formation of CaCO3, which filled the soil voids, and that the water content was reduced. To address issues with marine clay soil, this study aims to minimize the high cost of a special foundation system and the use of non-environmentally friendly materials such as calcium-based binders, aside from the reduction of deformations caused by loading. The findings of this study can be used for acidic soils and the improvement of soil’s geotechnical behavior in general.

Gallic acid and catechin are the most abundant phenolic and flavonoid contents found in all plant extracts. The contents and the bioassay-guided fractionating substances of the Sclerocarya birrea (A. Rich) Hochst (Anacardiaceae) fraction played vital roles. The goals of the study were to determine the contents of some useful medicinal plants and the bioassay-guided fractionation substances of S. birrea fraction compounds capable of acting against Salmonella isolate using LC-MS/LC-HRMS (Dionex ultimate 3000 RS UPLC with Thermo Scientific Q Exactive Orbitrap Hybrid Tandem Mass Spectrometer). The Folin–Ciocalteu reagent procedure and flavonoid content determination were conducted spectrophotometrically. Bioassay-guided fractionation, chronological partitioning, and screening of the antibacterial action against Salmonella typhi were performed. The ethyl acetate fraction extracts of S. birrea stem (bark) extract were analyzed using LC-MS/LC-HRMS. The gallic acid content increased tremendously in Vachellia nilotica (L.) P.J.H. Hurter and Mabb (Fabaceae) pod extracts with curve fitting (R2 = 0.9958). Catechin content increase was significantly increased in S. birrea stem (bark) extracts followed by that of V. nilotica pod extracts with curve fitting (R2 = 0.9993); they were all significantly different in the Guiera senegalensis J.F. Gmel. and the Leptadenia lanceolata (Poir.) Goyder leaves extracts at p value S. birrea stem (bark) ethyl acetate fraction extract was the MIC, where no MBC was recorded and susceptible to the positive control with the highest inhibition zone, followed by the ethyl acetate fraction extract at 10 mg/ml (9.7 ± 0.0) at Turkey’s p < 0.0001. Vidarabine is one of the novel compounds, specifically having antimicrobial actions, found in the S. birrea stem (bark). Reasonable amounts of phenolic and flavonoid contents determined the actions of the individual plant extract.

Scurrula ferruginea is a type of mistletoe from the Loranthaceae family found in Southeast Asia and distributed in tropical regions, is known to have healing effects for many disorders. Preservation of the bioactive metabolites is dependent on the sample preparation and drying methods as well as extraction solvents used. Thus, the present study was carried out to investigate the effect of different drying methods and extraction solvents on the total phenolic and the antioxidant activities of S. ferruginea leaves. The leaves of S. ferruginea were air and oven (60°C) dried and extracted with aqueous, organic and aqueous-organic solvents. The total phenolic content (TPC) and total flavonoid content (TFC) were used to gauge the phenolic antioxidants extracted, while the antioxidant activity was evaluated by measuring the scavenging effect on 2,2- diphenyl-1-picrylhydrazyl (DPPH) radical and via the ferric reducing antioxidant power (FRAP) assay. The optimum conditions obtained were oven drying, 80% acetone with values of 3.47 mg/10 g DW (extract yield), 171.29 mg GAE/1 g DW (TPC), 31.91 mg QE/1 g DW (TFC), 93.2% (DPPH), 26.41 mg TE/1 g DW (FRAP) and 7.41 μg/mL (IC50). The present findings suggested that sample preparation variability using different drying methods and solvents for extraction play a crucial role in enhancing the efficiency of extraction and efficacy of the antioxidant compounds in S. ferruginea leaf extracts.

Plants play vital roles in many health care systems, be it rural or an urban community. Plants became familiar as medicine due to the primordial ideologies and believed. Several plant parts served as medicines to so many ailments including gastrointestinal ailments, due to the fact that their active ingredients are powerful against the microbes as well as healing so many physiological abnormalities. The principal antimicrobial components were used to inhibit the growth of microbes (S. aureus, E. coli, Salmonella spp, B. cereus, and B. subtili,), as well as most of the recognized compounds in most plants were aromatic or saturated organic compounds which enabled the plants to be active against the gastrointestinal microbes. The commonly used diluents were; water, methanol and Di methyl sulphate oxides to ascertain the level of activity of the plants. As such, plant materials in one way or the other are very active when dealing with microbes due to their active ingredients or the phytoconstituents. Most of the microbes identified in many reviewed researches were enteric bacterial species, by which divided into both gram negative and gram positive bacterial isolates, they differ in their cell components, which are the main targets of bioactive constituents to deal with any bacteria. However, certain parasites contributed towards the production of ailments for their survival and causing havoc to the hosts and sometimes be mutualistic.

The soil environment is teeming with living organisms full of biological life and is one of the most abundant and diverse ecosystems on earth. However, due to unsustainable agriculture practices, the fertile topsoil is often lost; the soil becomes useless for agriculture. Therefore, we cannot lose sight of the fundamental role of the soil biological entities in maintaining the sustainability of the soil, and the role of organism’s biodiversity in the soil to counter against various stress. Therefore, the main objective of this work is detecting diversity and density of soil invertebrates between a cultivated field (Ladang 2) and uncultivated field (CEFS), Results showed that the highest abundance of invertebrates was recorded at CEFS 834 with 3.7 m2 density and the lowest was in Ladang 2: 225 with 1.2 m2 density, belonging to 35 different morphospecies from 4 Phylum, 4 subphyla, 6 class, 2 subclass, and 19 orders. A total of 15 morphospecies were collected in the cultivated field Ladang 2, while 25 morphospecies were collected in the uncultivated filed CEFS. Out of 25 morphospecies found in this area, 10 were exclusive to this environment. Annelida, Amphipoda, Isopoda, Collembola, and Hymenoptera were the dominant taxa in CEFS, comprising: 8.15%, 10.55%, 17.98%, 14.14%, and 26.97% respectively. But Acarina, Coleoptera, and Insect larva 39.68%, 5.95%, and 3.97% respectively were the dominant taxa in Ladang 2. The diversity was highest in the CEFS (H = 2.29) and lowest in the Ladang2 field (H = 1.74). Unfortunately, many aspects of the soil invertebrates have not been documented in Malaysia. For example, why they become dominant in a certain location and what is the impact on that particular ecosystem. This study showed that it is essential to maintain natural habitat because agricultural practices have a major influence on soil invertebrate diversity and hopefully through this study able to suggest sound agriculture management to safeguard the soil ecosystems. Due to the limited information about soil invertebrates in Malaysia and the limited scope of this study, it is premature to make any conclusion and therefore warrant further studies.

The floral micromorphology of critically endangered Paphiopedilum Pfitzer [P. barbatum (Lindl.) Pfitzer, P. callosum var. sublaeve (Rchb.f.) P.J.Cribb and P.niveum(Rchb.f.) Stein] were analyzed concerning either infrageneric taxonomy or physioecological demands. The first two species are phylogenetically close and superficially identical but occur with distinct phytogeographical distributions in the region. The third species is a phylogenetically distant congener that inhabits limestone areas in the northern part of Peninsular Malaysia. Using scanning electron microscopy (SEM), we investigated the surface of the dorsal sepal, synsepal, lateral petals, pouch or labellum, and staminode. Amongst the investigated features were epicuticular waxes, epicuticular ornamentation, trichome distribution and type, pustular glands, and papillae. Our study supports the distinction of P. barbatum from P. callosum var. sublaeve, which belong to subgenus Paphiopedilum, and from P. niveum, a species belonging to subgenus Brachypetalum, a separated monophyletic clade. Comparatively, P. barbatum has Type III non-glandular trichomes on the margin of its lateral petals, which are absent in P. callosum var. sublaeve. Paphiopedilum callosum var. sublaeve and P. niveum are distinguishable from P. barbatum by a confined distribution of papillae. The epicuticular ornamentation and distribution of trichomes on staminode discriminate between P. barbatum and P. callosum var. sublaeve and differentiates them from P. niveum. Compared to P. barbatum and P. niveum, stomata in P. callosum var. sublaeve were superficial with prominently raised guard cells. From the physioecological view, the absence of glandular trichomes, and the low occurrence of papillae and stomata on the floral parts explain the unscented flowers of P. barbatum and P. callosum var. sublaeve. A combination of the features examined is taxonomically valuable for delimitation of the species at the infrageneric level, although the diagnostic characters are far inadequate for a generic taxonomic revision. A study with a more extensive sampling from the three subgenera of Paphiopedilum, including subgenus Parvisepalum, is anticipated to elucidate the level of variation of the analyzed microcharacters. Key Words: physioecological importance, Peninsular Malaysia, subgenus Brachypetalum, subgenus Paphiopedilum, scanning electron microscopy, taxonomic delimitation Abstract. The floral micromorphology of critically endangered Paphiopedilum Pfitzer [P. barbatum (Lindl.) Pfitzer, P. callosum var. sublaeve (Rchb.f.) P.J.Cribb and P.niveum(Rchb.f.) Stein] were analyzed concerning either infrageneric taxonomy or physioecological demands. The first two species are phylogenetically close and superficially identical but occur with distinct phytogeographical distributions in the region. The third species is a phylogenetically distant congener that inhabits limestone areas in the northern part of Peninsular Malaysia. Using scanning electron microscopy (SEM), we investigated the surface of the dorsal sepal, synsepal, lateral petals, pouch or labellum, and staminode. Amongst the investigated features were epicuticular waxes, epicuticular ornamentation, trichome distribution and type, pustular glands, and papillae. Our study supports the distinction of P. barbatum from P. callosum var. sublaeve, which belong to subgenus Paphiopedilum, and from P. niveum, a species belonging to subgenus Brachypetalum, a separated monophyletic clade. Comparatively, P. barbatum has Type III non-glandular trichomes on the margin of its lateral petals, which are absent in P. callosum var. sublaeve. Paphiopedilum callosum var. sublaeve and P. niveum are distinguishable from P. barbatum by a confined distribution of papillae. The epicuticular ornamentation and distribution of trichomes on staminode discriminate between P. barbatum and P. callosum var. sublaeve and differentiates them from P. niveum. Compared to P. barbatum and P. niveum, stomata in P. callosum var. sublaeve were superficial with prominently raised guard cells. From the physioecological view, the absence of glandular trichomes, and the low occurrence of papillae and stomata on the floral parts explain the unscented flowers of P. barbatum and P. callosum var. sublaeve. A combination of the features examined is taxonomically valuable for delimitation of the species at the infrageneric level, although the diagnostic characters are far inadequate for a generic taxonomic revision. A study with a more extensive sampling from the three subgenera of Paphiopedilum, including subgenus Parvisepalum, is anticipated to elucidate the level of variation of the analyzed microcharacters. Key Words: physioecological importance, Peninsular Malaysia, subgenus Brachypetalum, subgenus Paphiopedilum, scanning electron microscopy, taxonomic delimitation

Polycyclic aromatic hydrocarbons (PAHs) comprised of many dangerous organic pollutants which affect human cell. The choice of phenanthrene and pyrene as model substrates was based on their classification among the most hazardous PAHs group by the US EPA where they belonged to low and high molecular weights PAHs respectively. Biodegradation of these PAHs is the best strategy that completely removes such pollutants in an environmentally friendly manner. However, the bacteria involved are challenged degradation difficulties as a result of PAHs inhibitory effects to the organisms. This research is aimed at formulating phenanthrene and pyrene degrading consortium that effectively perform best even in complex mixture with hazardous heavy metals. Different bacteria consortia were formulated using the compatibility testing and mathematical permutation approach and the best consortium selected. This selected consortium was then subjected to the degradation of both phenanthrene and pyrene separately in a combined mixture with the selected heavy metals from the inductively coupled plasma optical emission spectrophotometer (ICP-OES) analysis. Consortium composition of C. sakazakii MM045 (2%, v/v) and Enterobacter sp. MM087 (2%, v/v) were found to be much effective during phenanthrene (500 mg/L) and pyrene (250 mg/L) degradation. This consortium also resisted more than 6 mg/L each of Nickel (Ni), Cadmium (Cd), Vanadium (V) and Lead (Pb) in such complex degradation which was found to be more than the concentration in the natural habitat the consortium exists prior to isolation. Such performance makes the selected consortium to be an extremely efficient tool for the PAHs degradation application as many biodegradation agents were reported to be less effective when significant concentration of Ni, Cd, V and Pb are present.

Diuron is an alternative biocide suggested to replace organotin in formulating antifouling paints to be applied on water-going vessels hull. However, it is potentially harmful to various non-targeted marine organisms due to its toxic properties. Present study aimed to isolate, screen and identify the potential of Diuron-degrading bacteria collected from the marine sediments of Port Klang, Malaysia. Preliminary screening was conducted by exposing isolated bacteria to 430ng/L (background level), followed by 600ng/L and 1000ng/L of Diuron concentrations. Nine bacteria colonies survived the exposure of the above concentrations. However, only two strains can tolerate to survive up to 1000μg/L, which were then characterised and identified using phenotypic tests and the standard 16S rRNA molecular identification. The strains were identified as Comamonas jiangduensis SZZ 10 and Bacillus aerius SZZ 19 (GenBank accession numbers: KU942479 and KU942480, respectively). Both strains have the potential of Diuron biodegradation for future use.

Graphical abstract, Polycyclic Aromatic Hydrocarbons (PAHs) are complex and widely distributed environmental pollutants that can affect living ecosystems. This study was conducted to rapidly degrade phenanthrene and pyrene representing low and high molecular weight of PAHs, respectively. Cronobacter sakazakii MM045 (KT933253) was identified from used engine oil of contaminated soil. PAHs biodegradation was carried out using 2,6-dichlorophenol indophenol (DCPIP) assay. Biodegradation influencing factors including agitation, temperature, pH, inoculums volume and salinity were enhanced using Response Surface Methodology (RSM) by Central Composite Design (CCD). Phenanthrene and pyrene biodegrading metabolites were identified using gas chromatography mass spectrophotometer (GCMS). • Initial biodegradation indicated 75.2% and 54.3% phenanthrene and pyrene degraded by C. sakazakii MM045 within 24 h. After CCD optimisation, 100% degradation was achieved for each of the phenanthrene and pyrene, resulting in the formation of intermediate metabolites. • The identified phenanthrene metabolites were 3,4-dihydroxyphenathrene, phthalic acid, pyruvic acid, acetic acid and oxalic acid. Pyrene intermediates comprised pyrene cis-4,5-dihydrodiol, 3,4-dihydroxyphenanthrene, phthalic acid, pyruvic acid, acetic acid and lactic acid. • Cronbacter sakazakii MM045 was proven to be rapid and effective in degrading PAHs within 24 h despite the unavailability of existing literatures on PAHs biodegradation.

The uncontrolled logging in Peninsular Malaysia and the resulting mudslides in the lowland areas have been perilous, not to just humans, but also to another biodiversity, including the wild orchids. Their survival in these highly depleted areas is being overlooked due to the inaccessible and harsh environment. This paper reports on the rescue of orchids at risk from the disturbed forests for ex-situ conservation, the identification of the diversity of orchids and the evaluation of the influence of micro-climatic changes induced by clear-cut logging towards the resilience of orchids in the flood-disturbed secondary forests and logged forests in Terengganu and Kelantan, located at the central region of Peninsular Malaysia, where the forest destruction by logging activities has been extensive. 109 orchid species belonging to 40 genera were collected from the disturbed areas. The diversity and data analyses show that the disturbed secondary forests had a higher orchid density (0.0133 plants/m2) than the logged sites (0.0040 plants/m2) as the habitat conditions were more dependable. Nevertheless, the logged forests harboured a higher diversity of orchids (H=4.50 and D=0.99) of which 97.9% were epiphytes. Eleven rare species were found along with six species endemic to Peninsular Malaysia, with two species new to science. The results highlighted the factors that allow the orchids to flourish or suffer in the disturbed forests. The logged forests had a higher ambient temperature and lower moisture level than the mud flood-disturbed and canopy-covered secondary forests. Apart from the extensive ground vegetation due to logs dragging extraction, low soil moisture and absence of leaf litter were believed to be the major attributes causing the low abundance of terrestrial orchids. The high abundance and diversity of epiphytic orchids and the large difference of their densities between the logged sites were influenced by the densities of fallen trees hosting orchid(s), disturbance-induced dryness stresses, durations of exposure to the anthropogenic-induced disturbance, and less favourable soil conditions for the terrestrial orchids. The uncontrolled logging in Peninsular Malaysia and the resulting mudslides in the lowland areas have been perilous, not to just humans, but also to another biodiversity, including the wild orchids. Their survival in these highly depleted areas is being overlooked due to the inaccessible and harsh environment. This paper reports on the rescue of orchids at risk from the disturbed forests for ex-situ conservation, the identification of the diversity of orchids and the evaluation of the influence of micro-climatic changes induced by clear-cut logging towards the resilience of orchids in the flood-disturbed secondary forests and logged forests in Terengganu and Kelantan, located at the central region of Peninsular Malaysia, where the forest destruction by logging activities has been extensive. 109 orchid species belonging to 40 genera were collected from the disturbed areas. The diversity and data analyses show that the disturbed secondary forests had a higher orchid density (0.0133 plants/m2) than the logged sites (0.0040 plants/m2) as the habitat conditions were more dependable. Nevertheless, the logged forests harboured a higher diversity of orchids (H=4.50 and D=0.99) of which 97.9% were epiphytes. Eleven rare species were found along with six species endemic to Peninsular Malaysia, with two species new to science. The results highlighted the factors that allow the orchids to flourish or suffer in the disturbed forests. The logged forests had a higher ambient temperature and lower moisture level than the mud flood-disturbed and canopy-covered secondary forests. Apart from the extensive ground vegetation due to logs dragging extraction, low soil moisture and absence of leaf litter were believed to be the major attributes causing the low abundance of terrestrial orchids. The high abundance and diversity of epiphytic orchids and the large difference of their densities between the logged sites were influenced by the densities of fallen trees hosting orchid(s), disturbance-induced dryness stresses, durations of exposure to the anthropogenic-induced disturbance, and less favourable soil conditions for the terrestrial orchids.

Background Vibriosis is an important bacterial disease of cultured marine fishes worldwide. However, information on the virulence and antibiotic resistance of Vibrio spp. isolated from fish are scarce. This study investigates the distribution of virulence associated genes and antibiotic resistance patterns of Vibrio spp. isolated from cage-cultured marine fishes in Malaysia. Results A total of 63 Vibrio spp. isolated from 62 cultured marine fishes in various geographical regions in Peninsular Malaysia were analysed. Forty-two of the isolates (66.7%) were positive for all chiA, luxR and vhpA, the virulence genes produced by pathogenic V. harveyi. A total of 62 Vibrio isolates (98%) had tlh gene of V. parahaemolyticus, while flaC gene of V. anguillarum was detected in 43 of isolates (68%). Other virulence genes, including tdh, trh, hlyA and toxR vc were absent from any of the isolates. Multiple antibiotic resistance (MAR) was exhibited in all strains of Harveyi clade, particularly against ampicillin, penicillin, polypeptides, cephems and streptomycin. The MAR index ranged between 0.06 and 0.56, and 75% of the isolates have MAR index of higher than 0.20. Host species and geographical origin showed no correlation with the presence of virulence genes and the antibiotic resistance patterns of Vibrio spp. Conclusions The study indicates that majority of Vibrio spp. isolated from cultured marine fishes possess virulence genes, but were not associated with human pathogen. However, the antibiotics resistance is a real concern and warrants ongoing surveillance. These findings represent an updated knowledge on the risk of Vibrio spp. to human health, and also provides valuable insight on alternative approaches to combat vibriosis in cultured fish.

Scurrula ferruginea is a type of mistletoe from the Loranthaceae family found in Southeast Asia and distributed in tropical regions, is known to have healing effects for many disorders. Preservation of the bioactive metabolites is dependent on the sample preparation and drying methods as well as extraction solvents used. Thus, the present study was carried out to investigate the effect of different drying methods and extraction solvents on the total phenolic and the antioxidant activities of S. ferruginea leaves. The leaves of S. ferruginea were air and oven (60°C) dried and extracted with aqueous, organic and aqueous-organic solvents. The total phenolic content (TPC) and total flavonoid content (TFC) were used to gauge the phenolic antioxidants extracted, while the antioxidant activity was evaluated by measuring the scavenging effect on 2,2- diphenyl-1-picrylhydrazyl (DPPH) radical and via the ferric reducing antioxidant power (FRAP) assay. The optimum conditions obtained were oven drying, 80% acetone with values of 3.47 mg/10 g DW (extract yield), 171.29 mg GAE/1 g DW (TPC), 31.91 mg QE/1 g DW (TFC), 93.2% (DPPH), 26.41 mg TE/1 g DW (FRAP) and 7.41 μg/mL (IC50). The present findings suggested that sample preparation variability using different drying methods and solvents for extraction play a crucial role in enhancing the efficiency of extraction and efficacy of the antioxidant compounds in S. ferruginea leaf extracts.

Blood disease is a destructive bacterial infection that causes severe yield loss to the banana industry. Ideally, an environmental friendly yet practical approach is necessitated in the search for effective treatment against the disease. Endogeic earthworms are soil biota that help in improving soil physico-chemical and biological properties and thuspromote plant health. The present study assessed the effect of Pontoscolex corethrurus on banana infected by blood disease. The effect of earthworms was evaluated through observations on stem and root morphology, anatomy and total phenolic contents (TPC). P. corethrurus was inoculated into polybags planted with banana plantlets; inoculation of blood disease bacterium (BDB) into the roots of the plantlets was done using a drenching method. Stem and root sections of the plantlets were preserved in FAA for histological study upon harvest. The remaining sections were freeze-dried for TPC analysis. Root sections of plantlets infected with BDB showed lower root biomass compared to the control and earthworm-inoculated plantlets. Observations under microscope also showed that tissue necrosis at the vascular bundles of infected roots were more severe compared to the earthworm-inoculated and unaffected plantlets. Plantlets inoculated with earthworms had the highest root TPC, followed by the unaffected plantlets and plantlets infected with BDB. Although infected plantlets with earthworm inoculation showed disease symptoms, the disease severity was slightly less. The results suggested the potential role of P. corethrurus in improving plant health for disease management and sustainable agriculture.

Blood disease is a wilt disease that greatly affects the banana cultivation. Besides chemicals, the utilization of natural soil-biological entity may provide an alternative in searching for effective and environmental friendly approach against the disease. Endogeic earthworms are known as soil-engineers that modify soil properties that may favor or suppress different microbial populations. In the study, the effect of endogeic earthworm, Pontoscolex corethrurus on blood disease bacterium (BDB) was evaluated through in-vitro study. Earthworm casts, mucus and worm-worked soil collected were inoculated onto tetrazolium chloride (TZC) medium seeded with BDB at different concentrations. Molecular identification using 16S rRNA primers was then performed to identify the microbial isolates that inhibited BDB. Phylogenetic tree was constructed to determine the similarity among the isolates with Pseudomonas sp. sequences deposited in the GenBank. The results showed that bacterial colonies from earthworm mucus inhibited BDB at 103 and 105 cell/ml. However, no inhibition was observed at higher BDB concentration (107 cell/ml). Similarly, earthworm cast and worm-worked soil did not show inhibition towards BDB. Bacterial isolates obtained from earthworm mucus were classified into the genus Pseudomonas. The study suggested the potential role of P. corethrurus in enhancing the growth of beneficial microorganism in remediating blood disease.

A possible tributyltin (TBT)-degrading bacterium isolated from contaminated surface sediment was successfully identified as Klebsiella sp. FIRD 2. It was found to be the best isolate capable of resisting TBT at a concentration of 1000 μg L(-1). This was a concentration above the reported contaminated level at the sampling station, 790 μg L(-1). Further studies revealed that the isolate was Gram negative and resisted TBT concentrations of up to 1500 μg L(-1) in a Minimal Salt Broth without the addition of any carbon source within the first 48 h of incubation. It is expected that additional work could be conducted to check the degradation activity of this new isolate and possibly improve the degradation capacity in order to contribute to finding a safe and sustainable remediation solution of TBT contamination.

Streptococcus agalactiae is one of the most important pathogens infecting tilapia worldwide. In this study, we determined the serotype, sequence type (ST), virulence gene profile and pathogenicity of S. agalactiae isolated from cultured fish. A collection of 256 S. agalactiae that were previously isolated from outbreaks of streptococcosis in red hybrid tilapia in Peninsular Malaysia were studied. The genotype and ST of the isolates were determined by molecular serotyping of the capsular polysaccharide (cps) gene clusters, and multi-locus sequence typing (MLST). The virulence gene profiles were constructed using m-PCR for 14 standard virulence genes with published primers. Two serotypes, with different associated STs, were identified in this study: serotypes Ia ST7 and III ST283. Serotype Ia ST7 lacks lmb, scpB, pavA, fbsB, cyl, bca, cspA and bac genes, which were present in serotype III ST283. The LD50–240h of S. agalactiae in red hybrid tilapia for serotypes Ia ST7 and III ST283 were 8.7 × 103 CFU/mL and 6.3 × 103 CFU/mL, respectively. The histopathological findings were consistent with meningitis, necrosis of hepatocytes, coagulative tubular necrosis and hypocellular of the spleen. Histopathological scores revealed significant differences (p

This study investigated the environmental factors associated with the presence of Vibrionaceae in economically important cage-cultured tropical marine fishes: the Asian Seabass Lates calcarifer, snapper Lutjanus sp., and hybrid grouper Epinephelus sp. Fish sampling was conducted at monthly intervals between December 2016 and August 2017. The body weight and length of individual fish were measured, and the skin, eye, liver, and kidney were sampled for bacterial isolation and identification. Water physicochemical parameters during the sampling activities were determined, and the enumeration of total Vibrionaceae count was also conducted from water and sediment samples. Nine species of Vibrio were identified, including V. alginolyticus, V. diabolicus, V. harveyi, V. campbellii, V. parahaemolyticus, V. rotiferianus, V. furnissii, V. fluvialis, and V. vulnificus. Photobacterium damselae subsp. damselae was also identified. A total of 73% of the isolated Vibrio belonged to the Harveyi clade, followed by the Vulnificus clade (5.5%) and Cholera clade (0.6%). Highest occurrence of Vibrio spp. and P. damselae subsp. damselae was found in hybrid grouper (72%), followed by Asian Seabass (48%) and snapper (36%). The associations of Vibrio spp. and P. damselae subsp. damselae with the host fish were not species specific. However, fish mortality and fish size showed strong associations with the presence of some Vibrio spp. On average, 60% of the infected cultured fish exhibited at least one clinical sign. Nevertheless, inconsistent associations were observed between the pathogens and water quality. The yearlong occurrence and abundance of Vibrionaceae in the environmental components indicate that they might serve as reservoirs of these pathogens.