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This study aims to evaluate the effect of cell immobilization on bioactive property of lactobacilli‐fermented soymilk.

Agrowastes from durian (Durio zibethinus), cempedak (Artocarpus champeden), and mangosteen (Garcinia mangostana) were used as immobilizers for lactobacilli (Lactobacillus acidophilus FTDC 1331, L. acidophilus FTDC 2631, L. acidophilus FTDC 2333, L. acidophilus FTDC 1733, and L. bulgaricus FTCC 0411) in soymilk fermentation. Fermented soymilk was stored at different temperatures (4°C, 25°C and 37°C) for 168 h and sampled for analyses periodically.

Scanning electron micrographs showed that cells of lactobacilli were immobilized onto the matrix of agrowastes powder. The proteolytic activity was higher in soymilk supplemented with immobilized lactobacilli at 37°C and 25°C compared to that at 4°C. Soymilk fermented by cells immobilized on cempedak rind powder showed higher proteolytic activity (p<0.0001), followed by durian and mangosteen rinds powder (p<0.001). The highest ACE inhibitory activity was also found in soymilk fermented by cells immobilized on cempedak rind powder for all temperatures studied (p<0.0001). In addition, ACE inhibitory activity was higher in soymilk fermented at 37°C, compared to 25°C and 4°C (p<0.0001).

The results in the paper show that cell immobilization enhances the bioactive property of fermented soymilk, in terms of proteolysis and in‐vitro ACE inhibitory activity.

The purpose of this paper is to investigate the impact of antecedent factors on collaborative technologies usage among academic researchers in Malaysian research universities.

Data analysis was conducted on data collected from 156 academic researchers from five Malaysian research universities. This study employed an extensive quantitative approach of a structural equation modeling method to evaluate the research model and to test the hypotheses.

The main findings of this study are that personal innovativeness, task-technology fit, and perceived peer usage are significant predictors of individual usage of collaborative technologies; perceived managerial support and subjective norm were found not to be significant predictors to perceived usefulness and individual usage; and perceived usefulness is a significant mediator to individual usage in that it had fully mediated personal innovativeness whereas partially mediated peer usage.

The results provide practical insights into how the Malaysian higher education sector and other research organizations of not-for-profit structure could enhance their collaborative technologies usage.

This research is perhaps the first that concentrates on collaborative technologies usage in Malaysian research universities.

The purpose of the present study is to understand the role of auxin and cytokinin in stimulating the production of pigmented callus in Orthosiphon stamineus and to gain correlation between the callus colours with their antioxidant capacity and bioactive constituents.

In this study, plant tissue culture was used to induce production of callus of various colours from leaf explants of O. stamineus, via manipulation of plant hormones (0-2.0 mg L⁻¹ indole-3-acetic acid [IAA] and Kinetin [Kin]). The coloured callus was subjected to solvent extraction and used for quantification of its carotenoid, chlorophyll, anthocyanin and phenolic contents. The 2,2-diphenyl-1-picrylhydrazyl (DPPH) scavenging activity of the extracts was also evaluated, before and after four weeks of storage at −20°C.

The highest mean (per cent) explants that produced roots (93.33 ± 0.05 per cent) were observed when the cultures were supplemented with 2.0 mg L⁻¹ IAA. The colour of the callus changed with time, from green to cream to brown after two and four months of culture, respectively. Optimum production of green callus was achieved with addition of 2.0 mg L⁻¹ Kin plus 1.0-2.0 mg L⁻¹ IAA to the media, while cream callus in 0.5 mg L⁻¹ Kin plus 2.0 mg L⁻¹ IAA and brown callus in 0.5 mg L⁻¹ Kin plus 1.5 mg L⁻¹ IAA. Green callus was found to contain the highest amount of chlorophylls, carotenoid and anthocyanin, while cream callus contained the highest amount of phenolic compounds. The amount of pigments and secondary metabolites in the callus extracts decreased after four weeks of storage, except anthocyanin. The antioxidant potential of the extracts also increased after storage.

The major compounds identified in the methanolic extracts of O. stamineus-coloured callus are chlorophylls, carotenoids, flavonoids and phenolic acids. Future research work should include improvements in the extraction and identification methods which may lead to detection of other compounds that could attribute to the antioxidant capacity, to complement the findings of the current study.

This analysis provides valuable information on the application of IAA and Kinetin (Kin) to manipulate the content of major pigments with medicinal benefits in O. stamineus by using the plant tissue culture system.

A comparative study on antioxidant capacity and bioactive constituents of pigmented callus from O. stamineus leaves is original. To the best of the authors’ knowledge, this is the first attempt of comparative evaluation on antioxidant potential of O. stamineus-coloured callus produced using IAA and Kin.