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Fulltext Inhibitory activities of microalgal extracts against Epstein-Barr virus DNA release from lymphoblastoid cells

Kok YY, Chu WL, Phang SM, Mohamed SM, Naidu R, Lai PJ, et al.

J Zhejiang Univ Sci B, 2011 May;12(5):335-45.
PMID: 21528487 DOI: 10.1631/jzus.B1000336

This study aimed to assess the inhibitory activities of methanol extracts from the microalgae Ankistrodesmus convolutus, Synechococcus elongatus, and Spirulina platensis against Epstein-Barr virus (EBV) in three Burkitt's lymphoma (BL) cell lines, namely Akata, B95-8, and P3HR-1. The antiviral activity was assessed by quantifying the cell-free EBV DNA using real-time polymerase chain reaction (PCR) technique. The methanol extracts from Ankistrodesmus convolutus and Synechococcus elongatus displayed low cytotoxicity and potent effect in reducing cell-free EBV DNA (EC(50)<0.01 µg/ml) with a high therapeutic index (>28000). After fractionation by column chromatography, the fraction from Synechococcus elongatus (SEF1) reduced the cell-free EBV DNA most effectively (EC(50)=2.9 µg/ml, therapeutic index>69). Upon further fractionation by high performance liquid chromatography (HPLC), the sub-fraction SEF1'a was most active in reducing the cell-free EBV DNA (EC(50)=1.38 µg/ml, therapeutic index>14.5). This study suggests that microalgae could be a potential source of antiviral compounds that can be used against EBV.
Fulltext Understanding and reducing the fear of COVID-19

Ng KH, Kemp R

J Zhejiang Univ Sci B, 2020 9 8;21(9):752-754.
PMID: 32893533 DOI: 10.1631/jzus.B2000228

The world is now plagued by a pandemic of unprecedented nature caused by a novel, emerging, and still poorly understood infectious disease, coronavirus disease 2019 (COVID-19) (Wu and McGoogan, 2020). In addition to the rapidly growing body of scientific and medical literature that is being published, extensive public reports and stories in both the traditional media and social media have served to generate fear, panic, stigmatization, and instances of xenophobia (Zarocostas, 2020).
Fulltext Amino acid compounds released by the giant freshwater prawn Macrobrachium rosenbergii during ecdysis: a factor attracting cannibalistic behaviour?

Juneta-Nor AS, Noordin NM, Azra MN, Ma HY, Husin NM, Ikhwanuddin M

J Zhejiang Univ Sci B, 2020 10 13;21(10):823-834.
PMID: 33043647 DOI: 10.1631/jzus.B2000126

Ecdysis is a common phenomenon that happens throughout the life phase of the giant freshwater prawn Macrobrachium rosenbergii. It is vital to better understand the correlation between cannibalism and biochemical compound that exists during the moulting process. The objective of the present study was to determine the amino acid profile released by M. rosenbergii during the ecdysis process that promotes cannibalism. To accomplish this, changes in amino acid levels (total amino acid (TAA) and free amino acid (FAA)) of tissue muscle, exoskeleton, and sample water of culture medium from the moulting (E-stage) and non-moulting (C-stage) prawns were analysed using high-performance liquid chromatography (HPLC). Comparison study revealed that among the TAA compounds, proline and sarcosine of tissues from moulting prawn were found at the highest levels. The level of FAA from water that contains moulting prawns (E-stage) was dominated by tryptophan and proline. Significant values obtained in the present study suggested that these amino acid compounds act as a chemical cue to promote cannibalism in M. rosenbergii during ecdysis. The knowledge of compositions and compounds that were released during the moulting process should be helpful for better understanding of the mechanism and chemical cues that play roles on triggering cannibalism, and also for future dietary manipulation to improve feeding efficiencies and feeding management, which indirectly impacts productivity and profitability.
Fulltext Comparative effects of plant growth regulators on leaf and stem explants of Labisia pumila var. alata

Ling AP, Tan KP, Hussein S

J Zhejiang Univ Sci B, 2013 Jul;14(7):621-31.
PMID: 23825148 DOI: 10.1631/jzus.B1200135

OBJECTIVE: Labisia pumila var. alata, commonly known as 'Kacip Fatimah' or 'Selusuh Fatimah' in Southeast Asia, is traditionally used by members of the Malay community because of its post-partum medicinal properties. Its various pharmaceutical applications cause an excessive harvesting and lead to serious shortage in natural habitat. Thus, this in vitro propagation study investigated the effects of different plant growth regulators (PGRs) on in vitro leaf and stem explants of L. pumila.
METHODS: The capabilities of callus, shoot, and root formation were evaluated by culturing both explants on Murashige and Skoog (MS) medium supplemented with various PGRs at the concentrations of 0, 1, 3, 5, and 7 mg/L.
RESULTS: Medium supplemented with 3 mg/L indole-3-butyric acid (IBA) showed the optimal callogenesis from both leaf and stem explants with (72.34 ± 19.55)% and (70.40 ± 14.14)% efficacy, respectively. IBA was also found to be the most efficient PGR for root induction. A total of (50.00 ± 7.07)% and (77.78 ± 16.47)% of root formation were obtained from the in vitro stem and leaf explants after being cultured for (26.5 ± 5.0) and (30.0 ± 8.5) d in the medium supplemented with 1 and 3 mg/L of IBA, respectively. Shoot formation was only observed in stem explant, with the maximum percentage of formation ((100.00 ± 0.00)%) that was obtained in 1 mg/L zeatin after (11.0 ± 2.8) d of culture.
CONCLUSIONS: Callus, roots, and shoots can be induced from in vitro leaf and stem explants of L. pumila through the manipulation of types and concentrations of PGRs.
Acute and subacute oral toxicity of Litsea elliptica Blume essential oil in rats

Budin SB, Siti Nor Ain SM, Omar B, Taib IS, Hidayatulfathi O

J Zhejiang Univ Sci B, 2012 Oct;13(10):783-90.
PMID: 23024045

Litsea elliptica Blume has been traditionally used to treat headache, fever, and stomach ulcer, and has also been used as an insect repellent. The acute and subacute toxicities of L. elliptica essential oil were evaluated orally by gavage in female Sprague-Dawley rats. For the acute toxicity study, L. elliptica essential oil was administered in doses from 500 to 4000 mg/kg (single dose), and in the subacute toxicity test, the following doses were used: 125, 250, and 500 mg/kg, for 28 consecutive days. In the acute toxicity study, L. elliptica essential oil caused dose-dependent adverse behaviours and mortality. The median lethal dose value was 3488.86 mg/kg and the acute non-observed-adversed-effect level value was found to be 500 mg/kg. The subacute toxicity study of L. elliptica essential oil did not reveal alterations in body weight, and food and water consumptions. The haematological and biochemical analyses did not show significant differences between control and treated groups in most of the parameters examined, except for the hemoglobin, mean cell hemoglobin concentration, mean cell volume, mean cell hemoglobin, serum albumin, and serum sodium. However, these differences were still within the normal range. No abnormalities or histopathological changes were observed in the liver, pancreatic islet of Langerhans, and renal glomerulous and tubular cells of all treated groups. In conclusion, L. elliptica essential oil can be classified in the U group, which is defined as a group unlikely to present an acute hazard according to World Health Organization (WHO) classification.
Fulltext Toxic effects of Litsea elliptica Blume essential oil on red blood cells of Sprague-Dawley rats

Taib IS, Budin SB, Siti Nor Ain SM, Mohamed J, Louis SR, Das S, et al.

J Zhejiang Univ Sci B, 2009 Nov;10(11):813-9.
PMID: 19882755 DOI: 10.1631/jzus.B0920199

Litsea elliptica Blume leaves have been traditionally used as medicinal herbs because of its antimutagenicity, chemopreventative and insecticidal properties. In this study, the toxic effects of L. elliptica essential oil against Sprague-Dawley rat's red blood cells (RBCs) were evaluated. L. elliptica essential oil was given by oral gavage 5 times per week for 3 treated groups in the doses of 125, 250, and 500 mg/(kg body weight), respectively, and the control group received distilled water. Full blood count, RBC osmotic fragility, RBC morphological changes, and RBC membrane lipid were analyzed 28 d after the treatment. Although L. elliptica essential oil administration had significantly different effects on hemoglobin (Hb), mean cell hemoglobin concentration (MCHC), mean cell volume (MCV), and mean cell hemoglobin (MCH) in the experimental groups as compared to the control group (P<0.05), the values were still within the normal range. L. elliptica induced morphological changes of RBC into the form of echinocyte. The percentage of echinocyte increased significantly among the treated groups in a dose-response manner (P<0.001). The concentrations of RBC membrane phospholipids and cholesterol of all treated groups were significantly lower than those of control group (P<0.001). However, the RBC membrane osmotic fragility and total proteins of RBC membrane findings did not differ significantly between control and treated groups (P>0.05). It is concluded that structural changes in the RBC membrane due to L. elliptica essential oil administration did not cause severe membrane damage.
Fulltext Effects of temperature and diet on length-weight relationship and condition factor of the juvenile Malabar blood snapper (Lutjanus malabaricus Bloch & Schneider, 1801)

Mazumder SK, Das SK, Bakar Y, Ghaffar MA

J Zhejiang Univ Sci B, 2016 Aug;17(8):580-90.
PMID: 27487803 DOI: 10.1631/jzus.B1500251

In this study we aimed to analyze the effects of water temperature and diet on the length-weight relationship and condition of juvenile Malabar blood snapper Lutjanus malabaricus over a 30-d experimental period. The experiment was conducted in the laboratory using a flow-through-sea-water system. The fish were subjected to four different temperatures (22, 26, 30, and 34 °C) and two diets (commercial pellet and natural shrimp). Fish were fed twice daily. L. malabaricus exhibited negative allometric growth (b<3) at the beginning of the experiment (Day 0) at all temperatures and both diets except for 22 °C fed with shrimp, which showed isometric growth (b=3). Conversely, at the end of the experiment (Day 30) fish showed isometric growth (b=3) at 30 °C fed with the pellet diet, indicating that the shape of the fish did not change with increasing weight and length, and a positive allometric growth (b>3) at 30 °C fed with shrimp diet, which indicated that fish weight increases faster than their length. The rest of the temperatures represented negative allometric growth (b<3) on both diet, meaning that fish became lighter with increasing size. The condition factors in the initial and final measurements were greater than 1, indicating the state of health of the fish, except for those fed on a pellet diet at 34 °C. However, the best condition was obtained at 30 °C on both diets. Nevertheless, diets did not have a significant effect on growth and condition of juvenile L. malabaricus. The data obtained from this study suggested culturing L. malabaricus at 30 °C and feeding on the pellet or shrimp diet, which will optimize the overall production and condition of this commercially important fish species.
Fulltext Purification and identification of novel cytotoxic oligopeptides from soft coral Sarcophyton glaucum

Quah Y, Mohd Ismail NI, Ooi JLS, Affendi YA, Abd Manan F, Teh LK, et al.

J Zhejiang Univ Sci B, 2019 1 8;20(1):59-70.
PMID: 30614230 DOI: 10.1631/jzus.B1700586

Globally, peptide-based anticancer therapies have drawn much attention. Marine organisms are a reservoir of anticancer peptides that await discovery. In this study, we aimed to identify cytotoxic oligopeptides from Sarcophyton glaucum. Peptides were purified from among the S. glaucum hydrolysates produced by alcalase, chymotrypsin, papain, and trypsin, guided by a methylthiazolyldiphenyl-tetrazolium bromide (MTT) assay on the human cervical cancer (HeLa) cell line for cytotoxicity evaluation. Purification techniques adopted were membrane ultrafiltration, gel filtration chromatography, solid phase extraction (SPE), and reversed-phase high-performance liquid chromatography (RP-HPLC). Purified peptides were identified by de novo peptide sequencing. From papain hydrolysate, three peptide sequences were identified: AGAPGG, AERQ, and RDTQ (428.45, 502.53, and 518.53 Da, respectively). Peptides synthesized from these sequences exhibited cytotoxicity on HeLa cells with median effect concentration (EC50) values of 8.6, 4.9, and 5.6 mmol/L, respectively, up to 5.8-fold stronger than the anticancer drug 5-fluorouracil. When tested at their respective EC50, AGAPGG, AERQ, and RDTQ showed only 16%, 25%, and 11% cytotoxicity to non-cancerous Hek293 cells, respectively. In conclusion, AERQ, AGAPGG, and RDTQ are promising candidates for future development as peptide-based anticancer drugs.
Fulltext Unlocking the growth potential: harnessing the power of synbiotics to enhance cultivation of Pleurotus spp

Patil R, Ramli ANM, Xuan AS, Xin NZ, Azelee NIW, Bhuyar P

J Zhejiang Univ Sci B, 2024 Apr 15;25(4):293-306.
PMID: 38584092 DOI: 10.1631/jzus.B2300383

The oyster mushroom (Pleurotus spp.) is one of the most widely cultivated mushroom species globally. The present study investigated the effect of synbiotics on the growth and quality of Pleurotus ostreatus and Pleurotus pulmonarius. Different synbiotics formulations were applied by spraying mushroom samples daily and measuring their growth parameters, yield, biological efficiency, proximate composition, mineral content, total phenolic content (TPC), and diphenyl-1-picryl-hydrazyl (DPPH) radical scavenging activity. Results demonstrated that the most significant yield of oyster mushrooms was harvested from synbiotics sprayed with inulin and Lactobacillus casei (56.92 g). Likewise, the highest biological efficiency obtained with a similar synbiotic was 12.65%. Combining inulin and L. casei was the most effective method of improving the mushrooms' growth performance and nutrient content in both samples. Furthermore, synbiotics that combined inulin and L. casei resulted in the highest TPC (20.550 mg gallic acid equivalent (GAE)/g dry extract (DE)) in white oyster mushrooms (P. ostreatus). In comparison, in grey mushroom (P. pulmonarius) the highest TPC was yielded by L. casei (1.098 mg GAE/g DE) followed by inulin and L. casei (1.079 mg GAE/g DE). The DPPH results indicated that the oyster mushroom could be an efficient antioxidant. The results revealed that applying synbiotics improved the mushrooms' quality by increasing their antioxidant capacity with higher amounts of phenolic compounds and offering better health benefits with the increased levels of mineral elements. Together, these studies demonstrated the potential of using synbiotics as a biofertilizer, which is helpful for mushroom cultivation; therefore, it might solve the challenge of inconsistent quality mushroom growers face.
Fulltext Neural network and principal component regression in non-destructive soluble solids content assessment: a comparison

Chia KS, Abdul Rahim H, Abdul Rahim R

J Zhejiang Univ Sci B, 2012 Feb;13(2):145-51.
PMID: 22302428 DOI: 10.1631/jzus.B11c0150

Visible and near infrared spectroscopy is a non-destructive, green, and rapid technology that can be utilized to estimate the components of interest without conditioning it, as compared with classical analytical methods. The objective of this paper is to compare the performance of artificial neural network (ANN) (a nonlinear model) and principal component regression (PCR) (a linear model) based on visible and shortwave near infrared (VIS-SWNIR) (400-1000 nm) spectra in the non-destructive soluble solids content measurement of an apple. First, we used multiplicative scattering correction to pre-process the spectral data. Second, PCR was applied to estimate the optimal number of input variables. Third, the input variables with an optimal amount were used as the inputs of both multiple linear regression and ANN models. The initial weights and the number of hidden neurons were adjusted to optimize the performance of ANN. Findings suggest that the predictive performance of ANN with two hidden neurons outperforms that of PCR.

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