Modification of chitosan-bead support materials with l-lysine and l-asparagine for α-amylase immobilization

Bioprocess and Biosystems Engineering - Maltose syrups have got wide-range utilizations in a variety of applications from bakery to drug-development. α-Amylases are among the most widely...     

Assessing root nodule microsymbionts in healthy and declined rooibos (Aspalathus linearis burm f.) at a plantation in South Africa

Aspalathus linearis (burm f.), commonly known as rooibos, grows in nutrient and organic matter poor sandy soils that limit its growth. In this study, samples of nodules from both declined and healthy rooibos plants were collected to determine the frequency of nodule nitrogen-fixing and endophytic bacteria. Standard microbiological procedures as well as sequence analysis of the 16S rRNA revealed that more than 75% of the bacterial isolates from the healthy plants contained microsymbionts belonging to the Rhizobium group and the remaining 25% were characterized as Pseudomonas and Burkholderia spp. The nodule from the declined plants lacks a sufficient number of rhizobia and was mostly white in color, small and contains the free-living endospore-forming Bacillus and other endophytic Burkholderia and Pseudomonas spp. The results provide a baseline data on the microsymbionts of rooibos nodules in Citrusdal and highlighted the need for further investigation using additional techniques.     

Colony composition and queen behavior in polygynous colonies of the oriental ponerine antOdontomachus rixosus (Hymenoptera Formicidae)

Summary Colony composition and behavior of queens in the ponerine antOdontomachus rixosus were investigated in Bogor (West Java) and Ulu Gombak (Penisular Malaysia). The colonies had multiple dealate queens, with a maximum of 82 queens per colony. Majority of queens (92.4%) were inseminated and laid eggs, however, the degree of ovarian development slightly varied among individual queens. Queen behavior was observed for one colony in laboratory. Reproductive condition of individual queens was related with behavioral profiles. Virgin queens and mated queens having less developed ovaries engaged in foraging, larval care and grooming workers while fertile mated queens performed egg care and grooming queens. Aggressive interactions among coexisting queens were not observed.     

In vitro Antagonistic Interactions Between Endophytic Basidiomycetes of Oil Palm (Elaeis guineensis) and Ganoderma boninense

Ganoderma boninense is a white rot basidiomycete that causes basal stem rot disease of oil palm (Elaeis guineensis). The aims of this study were to identify endophytic basidiomycetes occurring naturally within oil palm and to assess their potential as biocontrol agents against G. boninense strain PER71 in vitro. In total, 376 isolates were recovered from samples collected from the root, stem and leaves of oil palm using Ganoderma‐selective medium. Ten of these isolates (2.7% of the total 376 isolates) were identified as basidiomycetes on the basis of clamp connections and the production of poroid basidiomes after incubation in glass jars containing PDA medium for 7–12 days. The isolates were identified using ITS rDNA sequencing as Neonothopanus nambi (five isolates), Schizophyllum commune (four isolates) and Ganoderma orbiforme (one isolate). The N. nambi isolates showed the greatest antagonistic activity against G. boninense, based on 73–85% inhibition of the radial growth measurements of G. boninense in dual culture and 76–100% inhibition of G. boninense growth in a culture filtrate assay. Possible modes of action for the antagonism shown by N. nambi against G. boninense in vitro include competition for substrate availability, space and the production of non‐volatile metabolites or antibiotics that inhibited the growth of G. boninense. Further in vivo investigations are required to determine the ability of N. nambi isolates to colonize oil palm seedlings and to protect oil palm from infection when challenged with G. boninense.     

Highly Fibrous and Porous Raw Material Shaped Chitin Isolated from <Emphasis Type="Italic">Oniscus</Emphasis> sp. (Crustacea)

Chitin was isolated from a crustacean by keeping the original body shape for the first time. The isolation method followed in this study was simple and time and energy saving unlike the labor-intensive classical methods. Chitin samples preserving the original shape were isolated from Isopoda (Oniscus sp.) successfully in a total of 20 min including filtration time. FT-IR, XRD and TGA analysis and chitinase digestion test demonstrated that the chitin was pure, low crystalline (Crystalline index: 51 %) and had low thermal stability (maximum degradation temperature: 328.8 °C). SEM analysis revealed the highly fibrous structure of chitin. The chitin content of the whole body was found significantly higher (29.6?±?4.2 %) than the earlier reports. Interaction of chitin isolates with Bovine Serum Albumin protein were studied at different pH. It was concluded that this three dimensional raw material shaped chitin can be effectively used in any adsorption studies due to 1) highly fibrous and porous nature, 2) low crystallinity and 3) low thermal stability. And also this biodegradable and biocompatible biopolymer can be suggested as a carrier matrix in further studies thanks to its three dimensional shape.     

Comparison of Different Protein Extraction Methods for Gel-Based Proteomic Analysis of <Emphasis Type="Italic">Ganoderma</Emphasis> spp.

Ganoderma species are a group of fungi that have the ability to degrade lignin polymers and cause severe diseases such as stem and root rot and can infect economically important plants and perennial crops such as oil palm, especially in tropical countries such as Malaysia. Unfortunately, very little is known about the complex interplay between oil palm and Ganoderma in the pathogenesis of the diseases. Proteomic technologies are simple yet powerful tools in comparing protein profile and have been widely used to study plant–fungus interaction. A critical step to perform a good proteome research is to establish a method that gives the best quality and a wide coverage of total proteins. Despite the availability of various protein extraction protocols from pathogenic fungi in the literature, no single extraction method was found suitable for all types of pathogenic fungi. To develop an optimized protein extraction protocol for 2-DE gel analysis of Ganoderma spp., three previously reported protein extraction protocols were compared: trichloroacetic acid, sucrose and phenol/ammonium acetate in methanol. The third method was found to give the most reproducible gels and highest protein concentration. Using the later method, a total of 10 protein spots (5 from each species) were successfully identified. Hence, the results from this study propose phenol/ammonium acetate in methanol as the most effective protein extraction method for 2-DE proteomic studies of Ganoderma spp.     

Recent advances in production of succinic acid from lignocellulosic biomass

Production of succinic acid via separate enzymatic hydrolysis and fermentation (SHF) and simultaneous saccharification and fermentation (SSF) are alternatives and are environmentally friendly processes. These processes have attained considerable positions in the industry with their own share of challenges and problems. The high-value succinic acid is extensively used in chemical, food, pharmaceutical, leather and textile industries and can be efficiently produced via several methods. Previously, succinic acid production via chemical synthesis from petrochemical or refined sugar has been the focus of interest of most reviewers. However, these expensive substrates have been recently replaced by alternative sustainable raw materials such as lignocellulosic biomass, which is cheap and abundantly available. Thus, this review focuses on succinic acid production utilizing lignocellulosic material as a potential substrate for SSF and SHF. SSF is an economical single-step process which can be a substitute for SHF — a two-step process where biomass is hydrolyzed in the first step and fermented in the second step. SSF of lignocellulosic biomass under optimum temperature and pH conditions results in the controlled release of sugar and simultaneous conversion into succinic acid by specific microorganisms, reducing reaction time and costs and increasing productivity. In addition, main process parameters which influence SHF and SSF processes such as batch and fed-batch fermentation conditions using different microbial strains are discussed in detail.     

Length–weight relationships of three fish species from a tropical mangrove estuary of Sarawak,Malaysia

Length–weight relationships for three mangrove fish species, Setipinna melanochir (Bleeker, 1849), Ilisha elongata (Anonymous [Bennett], 1830), and Nibea soldado (Lacépède, 1802) were determined. Samplings were conducted in a tropical mangrove estuary, Sarawak, Malaysia (3°59′25.76′′N; 113°43′51.6′′E) at the peak of three different seasons using gillnets (100 × 2.5 m, mesh sizes 1, 2 and 4 inches) during 2014–2015. No information regarding length–weight relationships of these species was reported previously in FishBase.     

<Emphasis Type="Italic">Amycolatopsis vastitatis</Emphasis> sp. nov., an isolate from a high altitude subsurface soil on Cerro Chajnantor,northern Chile

The taxonomic position of a novel Amycolatopsis strain isolated from a high altitude Atacama Desert subsurface soil was established using a polyphasic approach. The strain, isolate H5^T, was shown to have chemical properties typical of members of the genus Amycolatopsis such as meso-diaminopimelic acid as the diamino acid in the cell wall peptidoglycan, arabinose and galactose as diagnostic sugars and MK-9(H₄) as the predominant isoprenologue. It also has cultural and morphological properties consistent with its classification in the genus, notably the formation of branching substrate hyphae which fragment into rod-like elements. 16S rRNA gene sequence analyses showed that the strain is closely related to the type strain of Amycolatopsis mediterranei but could be distinguished from this and other related Amycolatopsis strains using a broad range of phenotypic properties. It was separated readily from the type strain of Amycolatopsis balhymycina, its near phylogenetic neighbour, based on multi-locus sequence data, by low average nucleotide identity (92.9%) and in silico DNA/DNA relatedness values (51.3%) calculated from draft genome assemblies. Consequently, the strain is considered to represent a novel species of Amycolatopsis for which the name Amycolatopsis vastitatis sp. nov. is proposed. The type strain is H5^T (= NCIMB 14970^T = NRRL B-65279^T).